Sample records for house dust lead

  1. The Contribution of Lead-Contaminated House Dust and Residential Soil to Children's Blood Lead Levels

    Microsoft Academic Search

    Bruce P. Lanphear; Thomas D. Matte; John Rogers; Robert P. Clickner; Brian Dietz; Robert L. Bornschein; Paul Succop; Kathryn R. Mahaffey; Sherry Dixon; Warren Galke; Michael Rabinowitz; Mark Farfel; Charles Rohde; Joel Schwartz; Peter Ashley; David E. Jacobs

    1998-01-01

    In 1992, the U.S. Congress passed the Residential Lead-Based Paint Hazard Reduction Act, which requires the promulgation of health-based dust lead and soil lead standards for residential dwellings to prevent undue lead exposure in children. Unfortunately, the levels of lead in house dust and soil that are associated with elevated blood lead levels among U.S. children remain poorly defined. This

  2. The Influence of Exterior Dust and Soil Lead on Interior Dust Lead Levels in Housing That Had Undergone Lead-Based Paint Hazard Control

    Microsoft Academic Search

    Scott Clark; William Menrath; Mei Chen; Paul Succop; Robert Bornschein; Warren Galke; Jonathan Wilson

    2004-01-01

    To aid in understanding the contribution of exterior dust\\/soil lead to postintervention interior dust lead, a subset of housing from the HUD Lead-Based Paint Hazard Control Grant Program Evaluation was selected for study. Housing from 12 state and local governments was included. Exterior entry and street dust samples were obtained by a vacuum method, and soil samples were building perimeter

  3. LEAD PAINT DISCLOSURE Housing built before 1978 may contain lead-based paint. Lead from paint, paint chips, and dust

    E-print Network

    Royer, Dana

    LEAD PAINT DISCLOSURE Housing built before 1978 may contain lead-based paint. Lead from paint, paint chips, and dust can pose health hazards if not taken care of properly. Lead exposure is especially the presence of known lead-based paint and lead-based paint hazards in the dwelling. Tenants must also receive

  4. Evolution of efficient methods to sample lead sources, such as house dust and hand dust, in the homes of children

    Microsoft Academic Search

    S. S. Que Hee; B. Peace; C. S. Clark; J. R. Boyle; R. L. Bornschein; P. B. Hammond

    1985-01-01

    Efficient sampling methods to recover lead-containing house dust and hand dust have been evolved so that sufficient lead is collected for analysis and to ensure that correlational analyses linking these two parameters to blood lead are not dependent on the efficiency of sampling. Precise collection of loose house dust from a 1-unit area (484 cmS) with a Tygon or stainless

  5. Canadian House Dust Study: Lead Bioaccessibility and Speciation

    SciTech Connect

    P Rasmussen; S Beauchemin; M Chenier; C Levesque; L MacLean; L Marrow; H Jones-Otazo; S Petrovic; L McDonald; H Gardner

    2011-12-31

    Vacuum samples were collected from 1025 randomly selected urban Canadian homes to investigate bioaccessible Pb (Pb{sub S}) concentrations in settled house dust. Results indicate a polymodal frequency distribution, consisting of three lognormally distributed subpopulations defined as 'urban background' (geomean 58 {micro}g g{sup -1}), 'elevated' (geomean 447 {micro}g g{sup -1}), and 'anomalous' (geomean 1730 {micro}g g{sup -1}). Dust Pb{sub S} concentrations in 924 homes (90%) fall into the 'urban background' category. The elevated and anomalous subpopulations predominantly consist of older homes located in central core areas of cities. The influence of house age is evidenced by a moderate correlation between house age and dust Pb{sub S} content (R{sup 2} = 0.34; n = 1025; p < 0.01), but it is notable that more than 10% of homes in the elevated/anomalous category were built after 1980. Conversely, the benefit of home remediation is evidenced by the large number of homes (33%) in the background category that were built before 1960. The dominant dust Pb species determined using X-ray Absorption Spectroscopy were as follows: Pb carbonate, Pb hydroxyl carbonate, Pb sulfate, Pb chromate, Pb oxide, Pb citrate, Pb metal, Pb adsorbed to Fe- and Al-oxyhydroxides, and Pb adsorbed to humate. Pb bioaccessibility estimated from solid phase speciation predicts Pb bioaccessibility measured using a simulated gastric extraction (R{sup 2} = 0.85; n = 12; p < 0.0001). The trend toward increased Pb bioaccessibility in the elevated and anomalous subpopulations (75% {+-} 18% and 81% {+-} 8%, respectively) compared to background (63% {+-} 18%) is explained by the higher proportion of bioaccessible compounds used as pigments in older paints (Pb carbonate and Pb hydroxyl carbonate). This population-based study provides a nationally representative urban baseline for applications in human health risk assessment and risk management.

  6. Evolution of efficient methods to sample lead sources, such as house dust and hand dust, in the homes of children.

    PubMed

    Que Hee, S S; Peace, B; Clark, C S; Boyle, J R; Bornschein, R L; Hammond, P B

    1985-10-01

    Efficient sampling methods to recover lead-containing house dust and hand dust have been evolved so that sufficient lead is collected for analysis, and to ensure that correlational analyses linking these two parameters to blood lead are not dependent on the efficiency of sampling. Precise collection of loose house dust from a 1-unit area (484 cm2) with a Tygon or stainless steel sampling tube connected to a portable sampling pump (1.2 to 2.5 liters/min) required repetitive sampling (three times). The Tygon tube sampling technique for loose house dust less than 177 microns in diameter was around 72% efficient with respect to dust weight and lead collection. A representative house dust contained 81% of its total weight in this fraction. A single handwipe for applied loose hand dust was not acceptably efficient or precise, and at least three wipes were necessary to achieve recoveries of greater than 80% of the lead applied. House dusts of different particle sizes less than 246 microns adhered equally well to hands. Analysis of lead-containing material usually required at least three digestions/decantations using hot plate or microwave techniques to allow at least 90% of the lead to be recovered. It was recommended that other investigators validate their handwiping, house dust sampling, and digestion techniques to facilitate comparison of results across studies. The final methodology for the Cincinnati longitudinal study was three sampling passes for surface dust using a stainless steel sampling tube; three microwave digestions/decantations for analysis of dust and paint; and three wipes with handwipes with one digestion/decantation for the analysis of six handwipes together. PMID:4076114

  7. The contribution of lead-contaminated house dust and residential soil to children`s blood lead levels

    SciTech Connect

    Lanphear, B.P. [Univ. of Cincinnati, OH (United States)] [Univ. of Cincinnati, OH (United States); Matte, T.D. [New York Academy of Medicine, New York, NY (United States). Center for Urban Epidemiologic Studies] [New York Academy of Medicine, New York, NY (United States). Center for Urban Epidemiologic Studies; Rogers, J. [Westat, Inc., Rockville, MD (United States)] [and others] [Westat, Inc., Rockville, MD (United States); and others

    1998-10-01

    In 1992, the US Congress passed the Residential Lead-Based Paint Hazard Reduction Act, which requires the promulgation of health-based dust lead and soil lead standards for residential dwellings to prevent undue lead exposure in children. Unfortunately, the levels of lead in house dust and soil that are associated with elevated blood lead levels among US children remain poorly defined. This pooled analysis was done to estimate the contributions of lead-contaminated house dust and soil to children`s blood lead levels. The results of this pooled analysis, the most comprehensive existing epidemiologic analysis of childhood lead exposure, confirm that lead-contaminated house dust is the major source of lead exposure for children. These analyses further demonstrate that a strong relationship between interior dust lead loading and children`s blood lead levels persists at dust lead levels considerably below the US Department of Housing and urban Development`s current post-abatement standards and the Environmental Protection Agency`s guidance levels. Finally, these analyses demonstrate that a child`s age, race, mouthing behaviors, and study-site specific factors influence the predicted blood lead level at a given level of exposure. These data can be used to estimate the potential health impact of alternative health-based lead standards for residential sources of lead exposure.

  8. [House dust mite allergy].

    PubMed

    Carrard, A; Pichler, C

    2012-04-01

    House dust mites can be found all over the world where human beings live independent from the climate. Proteins from the gastrointestinal tract- almost all known as enzymes - are the allergens which induce chronic allergic diseases. The inhalation of small amounts of allergens on a regular base all night leads to a slow beginning of the disease with chronically stuffed nose and an exercise induced asthma which later on persists. House dust mites grow well in a humid climate - this can be in well isolated dwellings or in the tropical climate - and nourish from human skin dander. Scales are found in mattresses, upholstered furniture and carpets. The clinical picture with slowly aggravating complaints leads quite often to a delayed diagnosis, which is accidently done on the occasion of a wider spectrum of allergy skin testing. The beginning of a medical therapy with topical steroids as nasal spray or inhalation leads to a fast relief of the complaints. Although discussed in extensive controversies in the literature - at least in Switzerland with the cold winter and dry climate - the recommendation of house dust mite avoidance measures is given to patients with good clinical results. The frequent ventilation of the dwelling with cold air in winter time cause a lower indoor humidity. Covering encasings on mattresses, pillow, and duvets reduces the possibility of chronic contact with mite allergens as well as the weekly changing the bed linen. Another option of therapy is the specific immunotherapy with extracts of house dust mites showing good results in children and adults. Using recombinant allergens will show a better quality in diagnostic as well as in therapeutic specific immunotherapy. PMID:22477664

  9. Lead Speciation in Indoor Dust: A Case Study to Assess Old Paint Contribution in a Canadian Urban House

    SciTech Connect

    S Beauchemin; L MacLean; P Rasmussen

    2011-12-31

    Residents in older homes may experience increased lead (Pb) exposures due to release of lead from interior paints manufactured in past decades, especially pre-1960s. The objective of the study was to determine the speciation of Pb in settled dust from an urban home built during WWII. X-ray absorption near-edge structure (XANES) and micro-X-ray diffraction (XRD) analyses were performed on samples of paint (380-2,920 mg Pb kg{sup -1}) and dust (200-1,000 mg Pb kg{sup -1}) collected prior to renovation. All dust samples exhibited a Pb XANES signature similar to that of Pb found in paint. Bulk XANES and micro-XRD identified Pb species commonly found as white paint pigments (Pb oxide, Pb sulfate, and Pb carbonate) as well as rutile, a titanium-based pigment, in the <150 m house dust samples. In the dust fraction <36 {mu}m, half of the Pb was associated with the Fe-oxyhydroxides, suggesting additional contribution of outdoor sources to Pb in the finer dust. These results confirm that old paints still contribute to Pb in the settled dust for this 65-year-old home. The Pb speciation also provided a clearer understanding of the Pb bioaccessibility: Pb carbonate > Pb oxide > Pb sulfate. This study underscores the importance of taking precautions to minimize exposures to Pb in house dust, especially in homes where old paint is exposed due to renovations or deterioration of painted surfaces.

  10. Lead speciation in indoor dust: a case study to assess old paint contribution in a Canadian urban house

    SciTech Connect

    Beauchemin, Suzanne; MacLean, Lachlan C.W.; Rasmussen, Pat E. (Health Canada); (NRC)

    2012-10-23

    Residents in older homes may experience increased lead (Pb) exposures due to release of lead from interior paints manufactured in past decades, especially pre-1960s. The objective of the study was to determine the speciation of Pb in settled dust from an urban home built during WWII. X-ray absorption near-edge structure (XANES) and micro-X-ray diffraction (XRD) analyses were performed on samples of paint (380-2,920 mg Pb kg{sup -1}) and dust (200-1,000 mg Pb kg{sup -1}) collected prior to renovation. All dust samples exhibited a Pb XANES signature similar to that of Pb found in paint. Bulk XANES and micro-XRD identified Pb species commonly found as white paint pigments (Pb oxide, Pb sulfate, and Pb carbonate) as well as rutile, a titanium-based pigment, in the <150 {micro}m house dust samples. In the dust fraction <36 {micro}m, half of the Pb was associated with the Fe-oxyhydroxides, suggesting additional contribution of outdoor sources to Pb in the finer dust. These results confirm that old paints still contribute to Pb in the settled dust for this 65-year-old home. The Pb speciation also provided a clearer understanding of the Pb bioaccessibility: Pb carbonate > Pb oxide > Pb sulfate. This study underscores the importance of taking precautions to minimize exposures to Pb in house dust, especially in homes where old paint is exposed due to renovations or deterioration of painted surfaces.

  11. An Examination of the Relationships between the U.S. Department of Housing and Urban Development Floor Lead Loading Clearance Level for Lead-Based Paint Abatement, Surface Dust Lead by a Vacuum Collection Method, and Pediatric Blood Lead

    Microsoft Academic Search

    Scott Clark; Robert L. Bornschein; Winkey Pan; William Menrath; Sandy Roda

    1995-01-01

    The U.S. Department of Housing and Urban Development (HUD) and several states have established floor and window dust lead clearance levels that must be met following lead-based paint abatement. These levels are also used as action levels to determine when exposure reduction measures are needed. Data are lacking on the relationship between these levels and the Centers for Disease Control

  12. Influenza A facilitates sensitization to house dust mite in infant mice leading to an asthma phenotype in adulthood

    Microsoft Academic Search

    A Al-Garawi; R Fattouh; F Botelho; T D Walker; S Goncharova; C-L Moore; M Mori; J S Erjefalt; D K Chu; A A Humbles; R Kolbeck; M R Stampfli; P M O'Byrne; A J Coyle; M Jordana

    2011-01-01

    The origins of allergic asthma, particularly in infancy, remain obscure. Respiratory viral infections and allergen sensitization in early life have been associated with asthma in young children. However, a causal link has not been established. We investigated whether an influenza A infection in early life alters immune responses to house dust mite (HDM) and promotes an asthmatic phenotype later in

  13. House Dust Mite and Dust Control

    Microsoft Academic Search

    Susan Pollart; Martin D. Chapman; Thomas A. E. Platts-Mills

    1988-01-01

    Conclusion  The available methods for controling dust mites in houses consist of washing bedding regularly, covering mattresses, and,\\u000a when possible, removing carpets. This leaves the problem of fitted carpets in living rooms, as welt as the problem of sofa\\u000a and chair upholsteries. These can be improved by vacuum cleaning, controling humidity, and perhaps using certain acaricides.\\u000a However, there is no perfect

  14. CHEMICAL CONTAMINANTS IN HOUSE DUST: OCCURRENCES AND SOURCES

    EPA Science Inventory

    Pesticides, polynuclear aromatic hydrocarbons (PAHs), lead (Pb), and other metals accumulate in home soil and house dust. xposure of infants and toddlers to Pb by dust may be greater than other pathways. any pollutants found in carpet dust are protected from degradation and accum...

  15. Polyfluoroalkyl chemicals in house dust

    SciTech Connect

    Kato, Kayoko [Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, 4770 Buford Hwy., Mailstop F53, Atlanta, GA 30341 (United States)] [Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, 4770 Buford Hwy., Mailstop F53, Atlanta, GA 30341 (United States); Calafat, Antonia M., E-mail: acalafat@cdc.gov [Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, 4770 Buford Hwy., Mailstop F53, Atlanta, GA 30341 (United States); Needham, Larry L. [Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, 4770 Buford Hwy., Mailstop F53, Atlanta, GA 30341 (United States)] [Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, 4770 Buford Hwy., Mailstop F53, Atlanta, GA 30341 (United States)

    2009-07-15

    We developed a high throughput analytical method using on-line solid phase extraction coupled with isotope dilution high-performance liquid chromatography-tandem mass spectrometry (on-line SPE-HPLC-MS/MS) to simultaneously determine the concentrations of 17 polyfluoroalkyl chemicals (PFCs) in house dust. The sample preparation includes dispersion of the dust samples in 0.1 M formic acid:MeOH (1:1), followed by agitation and filtration, addition of the isotope-labeled internal standard solution to the filtrate, and analysis by on-line SPE-HPLC-MS/MS. The limits of quantitation were <4.0 ng/g. The method accuracies ranged between 73.2% and 100.2% for the different analytes at two spike levels. We confirmed the validity of the method by analyzing 39 household dust samples collected in 2004. Of the 17 PFCs measured, 6 of them-perfluorobutane sulfonate (PFBuS), N-ethyl-perfluorooctane sulfonamide, 2-(N-ethyl-perfluorooctane sulfonamido) acetic acid (Et-PFOSA-AcOH), 2-(N-methyl-perfluorooctane sulfonamido) ethanol (Me-PFOSA-EtOH), perfluorohexane sulfonate (PFHxS), and perfluorooctane sulfonate (PFOS)-had detection frequencies >70%. We detected PFOS, PFBuS, and PFHxS at the highest median concentration, followed by Et-PFOSA-AcOH and Me-PFOSA-EtOH.

  16. Microbial communities associated with house dust.

    PubMed

    Rintala, Helena; Pitkäranta, Miia; Täubel, Martin

    2012-01-01

    House dust is a complex mixture of inorganic and organic material with microbes in abundance. Few microbial species are actually able to grow and proliferate in dust and only if enough moisture is provided. Hence, most of the microbial content originates from sources other than the dust itself. The most important sources of microbes in house dust are outdoor air and other outdoor material tracked into the buildings, occupants of the buildings including pets and microbial growth on moist construction materials. Based on numerous cultivation studies, Penicillium, Aspergillus, Cladosporium, and about 20 other fungal genera are the most commonly isolated genera from house dust. The cultivable bacterial flora is dominated by Gram-positive genera, such as Staplylococcus, Corynebacterium, and Lactococcus. Culture-independent studies have shown that both the fungal and the bacterial flora are far more diverse, with estimates of up to 500-1000 different species being present in house dust. Concentrations of microbes in house dust vary from nondetectable to 10(9) cells g(-1) dust, depending on the dust type, detection method, type of the indoor environment and season, among other factors. Microbial assemblages in different house dust types usually share the same core species; however, alterations in the composition are caused by differing sources of microbes for different dust types. For example, mattress dust is dominated by species originating from the user of the mattress, whereas floor dust reflects rather outdoor sources. Farming homes contain higher microbial load than urban homes and according to a recent study, temperate climate zones show higher dust microbial diversity than tropical zones. PMID:22305094

  17. An investigation into porch dust lead levels.

    PubMed

    Wilson, Jonathan; Dixon, Sherry L; Jacobs, David E; Akoto, Judith; Korfmacher, Katrina S; Breysse, Jill

    2015-02-01

    Lead in porch dust can expose children through direct contact or track-in to the home, but has not been adequately evaluated. At homes undergoing lead hazard control in Rochester, NY, we sampled settled dust lead on exterior porch floors at baseline, immediately post-lead hazard control and one-year post-work (n=79 homes with complete data) via wipe sampling and collected housing, neighborhood and soil data. Baseline GM porch floor dust lead loading (PbPD) was 68µg/ft(2), almost four times more than baseline GM interior floor dust lead (18µg/ft(2)). Immediate post-work PbPD declined 55% after porch floor replacement and 53% after porch floor paint stabilization (p=0.009 and p=0.041, respectively). When no porch floor work was conducted but lead hazard control was conducted elsewhere, immediate post-work PbPD increased 97% (p=0.008). At one-year, GM PbPD continued to decline for porch replacement (77% below baseline) and paint stabilization (72% below baseline), but where no porch floor work was done, GM PbPD was not significantly different than baseline (p<0.001, p=0.028 and p=0.504, respectively). Modeling determined that porch floor replacement had significantly lower one-year PbPD than stabilization when baseline PbPD levels were higher than 148µg/ft(2) (the 77th percentile) but not at lower levels. Treatment of porches with lead paint results in substantial declines in PbPD levels. It is of concern that PbPD levels increased significantly at immediate post-work when lead hazard control was not conducted on the porch but was conducted elsewhere. Standards for porch lead dust should be adopted to protect children from inadequate clean-up after lead hazard control. PMID:25531817

  18. House-dust-mite allergens: A review

    Microsoft Academic Search

    Larry G. Arlian

    1991-01-01

    The house-dust mites,Dermatophagoides farinae, D. pheronyssinus andEuroglyphus maynei are cosmopolitan inhabitants of the homes of humans worldwide. These mites are the sources of multiple potent allergens that trigger allergic reactions in house-dust-mite-sensitive individuals. Many laboratories using widely varied mite materials and allergic sera, and biochemical and immunological assays, have isolated and characterized, to varying degrees, some of the allergens produced

  19. Phylogenetic analysis of house dust mites

    Microsoft Academic Search

    Yubao Cui; Cuixiang Gao; Ying Zhou; Peng Zhou; Ming Peng; Yingzi Lin; Jianglong Peng

    2010-01-01

    House dust mites live in house dusts and affect the health of humans. Among the many species, Dermatophagoides farinae, D. pteronyssinus, and Euroglyphus maynei have been found to be commonly associated with Ig-E-mediated allergic diseases. As a result, there is increasing effort to\\u000a develop methods for the diagnosis and treatment of diseases caused by these species. The purpose of the

  20. The influence of social and environmental factors on dust lead, hand lead, and blood lead levels in young children

    Microsoft Academic Search

    R. L. Bornschein; P. Succop; K. N. Dietrich; C. S. Clark; S. Que Hee; P. B. Hammond

    1985-01-01

    The roles of environmental and behavioral factors in determining blood lead levels were studied in a cohort of young children living in an urban environment. The subjects were observed at 3-month intervals from birth to 24 months of age. Repeated measurements were made of the children's blood lead levels, environmental levels of lead in house dust, and in the dust

  1. Induction of atopic dermatitis by inhalation of house dust mite

    Microsoft Academic Search

    Ron A. Tupker; Jan G. R. De Monchy; Pieter J. Coenraads; Aafke Homan; Jan B. van der Meer

    1996-01-01

    BACKGROUND: The pathogenetic role of house dust mite in atopic dermatitis remains controversial. Recent studies have shown that intensive epicutaneous contact of house dust mite allergen with premanipulated skin may induce dermatitis. It is, however, uncertain whether such conditions are met during natural contact with house dust mite. In the past, allergen inhalation has been suggested to induce exacerbation of

  2. Source contributions of lead in residential floor dust and within-home variability of dust lead loading.

    PubMed

    Lucas, Jean-Paul; Bellanger, Lise; Le Strat, Yann; Le Tertre, Alain; Glorennec, Philippe; Le Bot, Barbara; Etchevers, Anne; Mandin, Corinne; Sébille, Véronique

    2014-02-01

    Evidence of the impact of exposure to low levels of lead on children's health is increasing. Residential floor dust is the assumed origin of lead exposure by young children. In this study, we estimate the contribution of different lead sources to household interior floor dust contamination. We also estimate the within-home variability of interior floor dust lead loadings. A multilevel model was developed based on data collected in a French survey in 2008-2009 (484 housing units, 1834 rooms). Missing data were handled by multiple imputation using chained equations. The intra-home correlation between interior floor Log dust lead loadings was approximately 0.6. Dust lead from the landing of an apartment, mostly originating outside the building, was the major contributor to interior floor dust lead. Secondary contributors included the lead-based paint on exterior railings, track-in of the exterior soil of the children's play area into the dwelling, smoking inside the home, demolition of nearby old buildings and sites of pollution in the vicinity. Interior lead-based paint contaminated interior floor dust only in old and non-renovated dwellings. To reduce interior floor dust lead levels in the general population of dwellings, common areas should be maintained, and track-in from the outside should be limited as much as possible. PMID:24184749

  3. A Comparison of the Lead Particle Content of Indoor Dust before and after a Lead Paint Abatement: A New Source of Lead Recontamination

    Microsoft Academic Search

    A. Hunt; J. Hawkins; E. Gilligan; S. Bhatia

    1998-01-01

    The lead particle content of floor dust in a housing unit scheduled for interior lead paint hazard removal was characterised microscopically to identify the contributing source(s) of the lead. It was hypothesised that elevated levels of lead in the dust resulted from the deterioration of the lead-based paint on the indoor surfaces. The question of lead particle source attribution was

  4. [House-dust mites as vectors of human diseases].

    PubMed

    Hoffmann, G

    1982-01-01

    The genuine European house-dust mite, Dermatophagoides pteronyssinus, is the producer of the most common and most potent allergen in the house-dust in Central Europe. Such allergens causing asthma, rhinitis, tracheitis, bronchitis and/or conjunctivitis in man may also be produced by the other species of house-dust mites such as D. farinae and Euroglyphus maynei. House mites and mites of stored products rarely account for such diseases but more frequently for acarodermatitis--especially on farms. Allergies due to house-dust mites mainly occur in midsummer and in early autumn. Particularly children under 10 years of age are effected by these allergies. Textile articles such as mattresses, upholstered furniture and carpets are breeding places of the genuine house-dust mites. Skin scales of humans, mammals and birds affected by mould provide the nutritional substrate of the mites. PMID:7184173

  5. House Dust Mite Hypersensitivity: Morning Dipping and Severity of Wheeze

    Microsoft Academic Search

    C. K. Connolly

    1981-01-01

    Atopic subjects with asthma are frequently hypersensitive to house dust mite (Dermatophagiodes pyteronyssinus). Exaggerated nocturnal or early morning wheezing might occur in these patients, because of exposure to the allergen during the night, particularly in, view of the biphasic response that it produces in airway resistance. This might be of diagnostic value in determining the relevance of house dust mite

  6. Characterization and Immunobiology of House Dust Mite Allergens

    Microsoft Academic Search

    Wayne R. Thomas; Wendy-Anne Smith; Belinda J. Hales; Kristina L. Mills; Richard M. O’Brien

    2002-01-01

    The examination of house dust mite extracts has indicated that over 30 different proteins can induce IgE antibody in patients allergic to the house dust mite. There are however dominant specificities especially the group 1 and 2 allergens which can account for much of the allergenicity of extracts. Of the 19 denominated allergens, the major IgE binding has been reported

  7. Immunomodulation of Skin Cytokine Secretion by House Dust Mite Extracts

    Microsoft Academic Search

    Larry G. Arlian; Marjorie S. Morgan

    2011-01-01

    Background: Skin contact with house dust mites may contribute to atopic dermatitis and other skin diseases. We sought to determine if molecules from house dust mites could influence the release of proinflammatory cytokines and chemokines from epidermal keratinocytes and dermal fibroblasts grown in a human skin equivalent (HSE) model. Methods: HSEs consisting of an epidermis of keratinocytes with stratum corneum

  8. Do Other Components of Bedding Dust Affect Sensitisation to House Dust Mites?

    PubMed Central

    Smith, Claire; Stanley, Thorsten; Crane, Julian; Siebers, Robert

    2011-01-01

    Bedding dust is a mixture of many components, of which the house dust mite (HDM) allergen, Der p 1, is the most allergenic. There has been little work to investigate the effect of other bedding dust components on HDM sensitisation. The objective of the study was to determine the effect of endotoxin in bedding dust on the allergic response in HDM-sensitised individuals. Twenty-nine house dust mite-sensitised adults were skin prick and allergen patch tested against a sterile solution of their own bedding dust and against a solution containing the same concentration of Der p 1 as the bedding solution for comparison. There was no significant difference in wheal size between the diluted house dust mite solution and the bedding dust in spite of their high levels of endotoxin. Symptomatic subjects had larger, but not statistically significant, responses to commercial house dust mite solution than asymptomatic subjects. Allergen patch test responses were negative in 22/29 of subjects using either bedding dust solutions or comparable diluted house dust mite solutions. An individual's own bedding dust does not appear to contain factors that enhance skin prick test or atopy patch test responses to house dust mites. PMID:23724237

  9. House dust mite allergy: environment evaluation and disease prevention

    PubMed Central

    Yu, Sheng-Jie; Liao, En-Chih

    2014-01-01

    There are two groups of dust mites, house dust mites (HDMs) and storage mites (SMs), that have been identified in the household environment. Both could induce airway inflammation through activation of innate and adaptive immunity and lead to asthma. In order to monitor environmental dust mite infestation, different methods can be used to detect their presence, such as the use of floating methods, monoclonal antibodies, and nanostructured biosensor. SM could be identified in the storage room, mainly in contaminated food such as mushrooms and corn starch. In HDM-sensitive subjects and mice that were challenged with HDM or SM after sensitization, these mites could up-regulate IgE levels, T helper 2 associated cytokine production and airway hypersensitivity. Different age groups of subjects were sensitized by different species of mites. More subjects above 70 years were sensitized by SM and more subjects below the age of 40 years were sensitized to HDM. Different allergenic components of dust mite extracts, such as Der p 1, Der p 2, could activate innate immunity through activating pattern recognition receptor (PRR) and then lead to allergic inflammation. The best modality to treat HDM allergy is immunomodulation through Treg cells and IgA production. In the recent years, many studies indicated probiotics could increase IgA secretion and the number of Treg cells. However, some studies conducted in adults have contradictory effects in reducing allergic symptoms. Therefore, probiotics confer inconclusive benefits on the allergic symptoms. PMID:25379484

  10. Guanine and mite allergenicity in house dust.

    PubMed

    Pauli, G; Hoyet, C; Tenabene, A; le Mao, J; Thierry, R; Bessot, J C

    1988-07-01

    Guanine is the major nitrogenous waste product in arachnids. It may serve as an indicator for allergenic mite faecal pellets. The present study assesses the correlation between the mit allergenicity of different house dust (HD) samples and their guanine content. Guanine content in HD samples was evaluated either by the Acarex-Test or determined quantitatively, especially for in-vitro methods. Using intradermal tests in selectively sensitized Dermatophagoides pteronyssinus (Dpt) patients, we evaluated the mite allergenicity of eight extracts obtained from HD samples with varying guanine contents. The weal area appeared to be proportional to the HD samples' guanine content. A three-fold increase in skin reactivity was observed when the guanine content varied from 0.06% to more than 1%. Patients allergic to HD but not to Dpt had no significant reactions with HD extract prepared from a guanine-rich HD sample. For eighteen different HD samples coupled to paper discs, the percentage Dpt RAST binding values obtained with a Dpt-selectively sensitized patient serum pool was correlated with the guanine concentrations of HD samples (P less than 0.01). The potencies of different HD extracts obtained from HD samples that varied in guanine content were also clearly distinguished on histamine-release titration curves. House dust obtained from homes at high altitude or from hospitals was generally guanine free. The HD sample guanine contents in homes where twelve Dpt-sensitized patients experienced symptoms were significantly higher than in homes where these patients were symptom free. The guanine colour test, a quick and easy technique, represents an important new development in indoor environmental investigations. It makes it possible to demonstrate mite faecal exposure and can be used to monitor the effectiveness of mite allergen avoidance measures. PMID:2458199

  11. Quantification of the Aspergillus versicolor allergen in house dust.

    PubMed

    Shi, Chunhua; Belisle, Donald; Miller, J David

    2011-09-30

    Aspergillus versicolor, a fungus commonly found on damp building materials, produces the allergen, Asp v 13. Here we report a sensitive Asp v 13 capture ELISA for A. versicolor spores and spore- and mycelial fragments in house dust samples. The method is based on a double polyclonal capture ELSIA. The detection limits for Asp v 13 antigen and A. versicolor spores without dust were 2.44 pg and 12 ng (ca. 110 spores). Detection limits for Asp v 13 and A. versicolor spores in sieved house dust samples were 1.0 ng and 7.8 ?g per gram dry weight house dust, respectively. This detection limit is lower than for other house dust allergen immunoassays including for Stachybotrys chartarum, Aspergillus fumigatus, but much lower than that from Alternaria alternata. PMID:21763696

  12. Modification of House Dust Mite Allergens by Monomethoxypolyethylene Glycol

    Microsoft Academic Search

    H. Mosbech; S. Dreborg; I. Pĺhlman; P. Stahl Skov; I. Steringer; B. Weeke

    1988-01-01

    In animal models, allergen modification by coupling to monomethoxypolyethylene glycol (mPEG) molecules can reduce allergenicity of the extract and makes the allergen capable of suppressing boosted IgE response. To investigate in a human system the degree of attenuation implied by a mPEG modification of a house dust mite (Dermatophagoides pteronyssinus) extract, 55 adults with asthma caused by house dust mites

  13. House dust in seven Danish offices

    NASA Astrophysics Data System (ADS)

    Mřlhave, L.; Schneider, T.; Kjćrgaard, S. K.; Larsen, L.; Norn, S.; Jřrgensen, O.

    Floor dust from Danish offices was collected and analyzed. The dust was to be used in an exposure experiment. The dust was analyzed to show the composition of the dust which can be a source of airborne dust indoors. About 11 kg of dust from vacuum cleaner bags from seven Danish office buildings with about 1047 occupants (12 751 m 2) was processed according to a standardized procedure yielding 5.5 kg of processed bulk dust. The bulk dust contained 130.000-160.000 CFU g -1 microorganisms and 71.000-90.000 CFU g -1 microfungi. The content of culturable microfungi was 65-123 CFU 30 g -1 dust. The content of endotoxins ranged from 5.06-7.24 EU g -1 (1.45 ng g -1 to 1.01 ng g -1). Allergens (ng g -1) were from 147-159 (Mite), 395-746 (dog) and 103-330 (cat). The macro molecular organic compounds (the MOD-content) varied from 7.8-9.8 mg g -1. The threshold of release of histamine from basophil leukocytes provoked by the bulk dust was between 0.3 and 1.0 mg ml -1. The water content was 2% (WGT) and the organic fraction 33%. 6.5-5.9% (dry) was water soluble. The fiber content was less than 0.2-1.5% (WGT) and the desorbable VOCs was 176-319 ?g g -1. Most of the VOC were aldehydes. However, softeners for plastic (DBP and DEHP) were present. The chemical composition includes human and animal skin fragments, paper fibers, glass wool, wood and textilefibers and inorganic and metal particles. The sizes ranged from 0.001-1 mm and the average specific density was 1.0 g m -3. The bulk dust was resuspended and injected into an exposure chamber. The airborne dust was sampled and analyzed to illustrate the exposures that can result from sedimented dirt and dust. The airborne dust resulting from the bulk dust reached concentrations ranging from 0.26-0.75 mg m -3 in average contained 300-170 CFU m -3. The organic fraction was from 55-70% and the water content about 2.5% (WGT). The content of the dust was compared to the similar results reported in the literature and its toxic potency is estimated to be relatively low. The storage of the bulk dust during the experiment had little effect on the specific biological and chemical composition.

  14. [Japanese cedar pollen in house dust].

    PubMed

    Enomoto, T; Ohnishi, S; Dake, Y; Sakoda, T; Saitoh, Y; Sogo, H; Seno, S; Fujiki, Y; Fujimura, S

    2001-06-01

    Caring for oneself against Japanese cedar pollinosis is important as well as receiving medical-care. Although the importance of avoiding pollen is described in the guideline for nasal allergy medical treatment, however, there is no information for effective dust cleaning for the home. This study examined how many cedar pollens were included in indoor dust in order to obtain basic data whether dust removal for cedar pollen is available for pollinosis suffers. As a result, the study found that there were many Japanese cedar pollens in indoor dust even before the pollen season. Cedar pollen increased with the increasing number of airborne pollen. The highest number of pollen found in one week was approximately 450 pollens in a square meter of a living room floor. The study concluded that cleaning is one of the best way to remove Japanese cedar pollens found in indoor dust. PMID:11517516

  15. Continuous Exposure to House Dust Mite Elicits Chronic Airway Inflammation and Structural Remodeling

    Microsoft Academic Search

    Jill R. Johnson; Ryan E. Wiley; Ramzi Fattouh; Filip K. Swirski; Beata U. Gajewska; Anthony J. Coyle; Jose ´-Carlos Gutierrez-Ramos; Russ Ellis; Mark D. Inman; Manel Jordana

    It is now fully appreciated that asthma is a disease of a chronic nature resulting from intermittent or continued aeroallergen expo- sure leading to airway inflammation. To investigate responses to continuous antigen exposure, mice were exposed to either house dust mite extract (HDM) or ovalbumin intranasally for five consecu- tive days, followed by 2 days of rest, for up to

  16. Polybrominated diphenyl ethers (PBDEs) in house dust in Beijing, China.

    PubMed

    Li, K; Fu, S

    2013-10-01

    Eleven house dust samples were collected in Beijing to quantify 42 different polybrominated diphenyl ethers (PBDEs). Total PBDEs concentrations ranged from 140 to 1,300 ng g(-1). The dominant PBDEs congener identified was BDE 209, which made up more than 70% of all PBDEs congeners. Concentrations of PBDEs in Chinese house dust were lower than in other countries. The most polluted areas were electronics shops and households. It is likely that PBDEs exposure is a potential threat for Beijing residents, particularly toddlers. PMID:23995797

  17. Zinc in house dust: speciation, bioaccessibility, and impact of humidity.

    PubMed

    Beauchemin, Suzanne; Rasmussen, Pat E; MacKinnon, Ted; Chénier, Marc; Boros, Kristina

    2014-08-19

    Indoor exposures to metals arise from a wide variety of indoor and outdoor sources. This study investigates the impact of humid indoor conditions on the bioaccessibility of Zn in dust, and the transformation of Zn species during weathering. House dust samples were subjected to an oxygenated, highly humid atmosphere in a closed chamber for 4 to 5 months. Zinc bioaccessibility before and after the experiment was determined using a simulated gastric acid extraction. Bulk and micro X-ray absorption structure (XAS) spectroscopy was used to speciate Zn in dust. Exposure to humid conditions led to a significant increase in Zn bioaccessibility in all samples, which was due to a redistribution of Zn from inorganic forms toward the organic pools such as Zn adsorbed on humates. ZnO readily dissolved under humid conditions, whereas ZnS persisted in the dust. Elevated humidity in indoor microenvironments may sustain higher Zn bioaccessibility in settled dust compared to drier conditions, and part of this change may be related to fungal growth in humid dust. These results help to explain the greater bioaccessibility of certain metals in house dust compared to soils. PMID:25041107

  18. Estimating outdoor and indoor dust lead levels from accidental bridge repair containment releases

    SciTech Connect

    Cohen, J.T.; Conway, R.F.

    1999-07-01

    A 1998 New York City Department of Transportation (NYCDOT) environmental impact statement (EIS) evaluated the proposed removal of deteriorated lead paint from NYCDOT-owned bridges. The EIS health risk assessment quantified the potential impact of particulate releases on blood lead levels among members of the public living and working near affected bridges. The risk assessment consisted of a fate and transport component and an exposure-dose component. The fate and transport component, modeled using the EPA's Industrial Source Complex (ISC3) model, calculated the impact of paint removal activities on ambient air lead concentrations and dust lead deposition rates. The exposure-dose component, modeled using EPA's Integrated Exposure Uptake Biokinetic (IEUBK) model, the Bowers et al. Adult Lead model, and the O'Flaherty lead model, calculated the impact of additional lead in air, street dust, interior house dust, and soil on blood lead levels, a conventional measure of body lead burden. The analysis was complicated because the ISC3 model provides a dust lead deposition rate ({micro}g/m{sup 2}-day), while the IEUBK, Bowers et al., and O'Flaherty models demand as input specification of dust lead concentrations ({micro}g lead per g dust). This paper describes a model developed for the EIS that quantifies long term average dust lead concentrations associated with typical bridge containment releases, and short term dust lead concentration spikes following worst case release events associated with bridge repair containment structure failures. The model reflects the influence of both lead and other debris associated with bridge repair activities, the contribution of background debris to street dust, and the impact of rainfall on removal of both lead and other material from the street dust reservoir.

  19. Modeling Responses to Respiratory House Dust Mite Exposure

    Microsoft Academic Search

    E. Cates; R. Fattouh; J. Johnson; A. Llop-Guevara; M. Jordana

    2007-01-01

    House dust mite (HDM) is the most pervasive indoor aeroallergen source worldwide. Allergens derived from HDM are associated with sensitization and allergic asthma. Allergic asthma is an immunologically driven disease characterized by a Th2-polarized immune response, eosinophilic inflammation, airway hyperreactivity, and remodeling. Animal models of asthma utilizing ovalbumin (OVA) exposure have afforded us considerable insight with respect to the mediators

  20. Polybrominated diphenyl ethers in house dust in Singapore

    Microsoft Academic Search

    Jing Tan; Si Min Cheng; Annamalai Loganath; Yap Seng Chong; Jeffrey Philip Obbard

    2007-01-01

    The use of polybrominated diphenyl ethers (PBDEs) as flame retardants in Singapore is not strictly regulated; therefore these compounds can be readily found in furniture, electronic devices, and building materials. This study was the first of its kind to be conducted in Singapore to measure concentrations of PBDEs in house dust. Samples were collected from 31 homes in various locations

  1. Association of House Dust Allergen Concentrations With Residential Conditions in City and in Rural Houses

    PubMed Central

    Wardzy?ska, Aleksandra; Majkowska-Wojciechowska, Barbara; Pe?ka, Jolanta; Korzon, Leszek; Kacza?a, Magdalena; Jarz?bska, Marzanna; Gwardys, Tomasz

    2012-01-01

    Background The aim of the study was to evaluate the relationship between house dust mite, cat and dog allergen levels with household characteristics in the houses of children living in urban and rural areas in central Poland. Methods Dust samples were collected from 141 urban and 191 rural houses. Der f1 + Der p1, Can f 1, and Fel d1 levels were measured and associated with residential conditions and atopy-related health outcomes assessed by clinical examination and skin prick testing. Results Concentrations of mite allergens were lower, and cat and dog allergen levels were higher in urban houses. Fel d1 and Can f1 levels depended on the presence of a respective animal in the house. In urban houses, Der p1 + Der f1 concentration was lower in households with central heating, whereas Can f1 concentration was related to building age. Multivariate analyses revealed that the concentrations of house dust mite and dog allergens were associated with relative humidity, number of people in the household, and the presence of a dog at home. There was no significant association between allergen level and sensitization or atopic diseases. Conclusions Concentrations of indoor allergens in urban and rural houses differ significantly, and residential conditions associated with allergen levels seem to be different in both environments. PMID:23268467

  2. DEVELOPING AND IMPLEMENTING A LEAD DUST MONITORING, OUTREACH AND EDUCATION PROGRAM IN YOUR COMMUNITY/SYRACUSE LEAD DUST PROJECT

    EPA Science Inventory

    EPA has developed a technology transfer document (case-study) for the EMPACT Syracuse Lead Dust Project. The Lead Dust Project is designed to measure the lead dust content in homes and public buildings within the City of Syracuse, NY. The project also contains an educational comp...

  3. Effect of house dust mite avoidance measures on adult atopic asthma

    Microsoft Academic Search

    A J Dorward; M J Colloff; N S MacKay; C McSharry; N C Thomson

    1988-01-01

    Twenty one adult patients with asthma, with positive skin test responses to the European house dust mite, Dermatophagoides pteronyssinus, were randomly allocated to a control group or to a group applying house dust mite avoidance measures. These included an initial application of liquid nitrogen to mattresses and bedroom carpets to kill the live house dust mite population. Histamine airway responsiveness,

  4. Surface dust wipes are the best predictors of blood leads in young children with elevated blood lead levels

    SciTech Connect

    Gulson, Brian, E-mail: brian.gulson@mq.edu.au [Graduate School of the Environment, Macquarie University, North Ryde NSW 2109 (Australia) [Graduate School of the Environment, Macquarie University, North Ryde NSW 2109 (Australia); CSIRO Earth Science and Resource Engineering, North Ryde NSW 2113 (Australia); Anderson, Phil [Information and Statistics Group, Australian Institute of Health and Welfare, Canberra ACT 2601 (Australia) [Information and Statistics Group, Australian Institute of Health and Welfare, Canberra ACT 2601 (Australia); Faculty of Health, University of Canberra, Canberra ACT 2601 (Australia); Taylor, Alan [Department of Psychology, Macquarie University, Sydney NSW 2109 (Australia)] [Department of Psychology, Macquarie University, Sydney NSW 2109 (Australia)

    2013-10-15

    Background: As part of the only national survey of lead in Australian children, which was undertaken in 1996, lead isotopic and lead concentration measurements were obtained from children from 24 dwellings whose blood lead levels were ?15 µg/dL in an attempt to determine the source(s) of their elevated blood lead. Comparisons were made with data for six children with lower blood lead levels (<10 µg/dL). Methods: Thermal ionisation and isotope dilution mass spectrometry were used to determine high precision lead isotopic ratios ({sup 208}Pb/{sup 206}Pb, {sup 207}Pb/{sup 206}Pb and {sup 206}Pb/{sup 204}Pb) and lead concentrations in blood, dust from floor wipes, soil, drinking water and paint (where available). Evaluation of associations between blood and the environmental samples was based on the analysis of individual cases, and Pearson correlations and multiple regression analyses based on the whole dataset. Results and discussion: The correlations showed an association for isotopic ratios in blood and wipes (r=0.52, 95% CI 0.19–0.74), blood and soil (r=0.33, 95% CI ?0.05–0.62), and blood and paint (r=0.56, 95% CI 0.09–0.83). The regression analyses indicated that the only statistically significant relationship for blood isotopic ratios was with dust wipes (B=0.65, 95% CI 0.35–0.95); there were no significant associations for lead concentrations in blood and environmental samples. There is a strong isotopic correlation of soils and house dust (r=0.53, 95% CI 0.20–0.75) indicative of a common source(s) for lead in soil and house dust. In contrast, as with the regression analyses, no such association is present for bulk lead concentrations (r=?0.003, 95% CI ?0.37–0.36), the most common approach employed in source investigations. In evaluation of the isotopic results on a case by case basis, the strongest associations were for dust wipes and blood. -- Highlights: • Children with elevated blood lead ?15 µg/dL compared with a group with <10 µg/dL. • High precision lead isotopic ratios in blood, house dust wipes, soil, water, paint. • Associations for isotopic measures of blood and dust, blood and soil, blood and paint. • Regressions gave significance for isotopic measures of blood/dust and dust/soil.

  5. Photodegradation of decabromodiphenyl ether in house dust by natural sunlight.

    PubMed

    Stapleton, Heather M; Dodder, Nathan G

    2008-02-01

    Photolytic degradation of decabromodiphenyl ether (BDE 209) has been observed in several matrices such as solvent/ water mixtures, sediments, and soil; however, no studies have investigated the degradation potential of BDE 209 in house dust. In the present study, both a natural and a BDE 209-spiked dust material were exposed to sunlight for 200 cumulative h. Degradation of BDE 209 was observed in both matrices but was 35% greater in the spiked dust relative to the natural dust material. The pseudo- first-order degradation rates were 2.3 x 10(-3) and 1.7 x 10(-3) per hour for the spiked and natural dust, respectively. During the 200-h exposure, as much as 38% of the original BDE 209 mass was degraded in the spiked dust, 25% of which could not be accounted for and was lost to unknown pathways and/or products. The remaining 13% was accounted for by the formation of lower brominated congeners. Debrominated products detected in the spiked dust included all three nonabrominated congeners (BDE 206, BDE 207, and BDE 208) and several octabrominated congeners (BDE 196, BDE 197, BDE 201, BDE 202, and BDE 203/200). In technical commercial octa-BDE mixtures, BDE 201 is a very small component (below detection limit to 0.8%), and BDE 202 is not detected. Therefore, the presence of these congeners in house dust may provide a marker of environmental debromination of BDE 209. The ratio of BDE 197 to BDE 201 may also be indicative of BDE 209 degradation. as the ratio of these two congeners appeared to reach a steady-state value (~1) in both exposure scenarios in the present study. PMID:18348638

  6. Innate Immune Responses in House Dust Mite Allergy

    PubMed Central

    Jacquet, Alain

    2013-01-01

    Sensitizations to house dust mites (HDM) trigger strong exacerbated allergen-induced inflammation of the skin and airways mucosa from atopic subjects resulting in atopic dermatitis as well as allergic rhinitis and asthma. Initially, the Th2-biased HDM allergic response was considered to be mediated only by allergen B- and T-cell epitopes to promote allergen-specific IgE production as well as IL-4, IL-5, and IL-13 to recruit inflammatory cells. But this general molecular model of HDM allergenicity must be revisited as a growing literature suggests that stimulations of innate immune activation pathways by HDM allergens offer new answers to the following question: what makes an HDM allergen an allergen? Indeed, HDM is a carrier not only for allergenic proteins but also microbial adjuvant compounds, both of which are able to stimulate innate signaling pathways leading to allergy. This paper will describe the multiple ways used by HDM allergens together with microbial compounds to control the initiation of the allergic response through engagement of innate immunity. PMID:23724247

  7. Immunomodulation of Skin Cytokine Secretion by House Dust Mite Extracts

    PubMed Central

    Arlian, Larry G.; Morgan, Marjorie S.

    2011-01-01

    Background Skin contact with house dust mites may contribute to atopic dermatitis and other skin diseases. We sought to determine if molecules from house dust mites could influence the release of proinflammatory cytokines and chemokines from epidermal keratinocytes and dermal fibroblasts grown in a human skin equivalent (HSE) model. Methods HSEs consisting of an epidermis of keratinocytes with stratum corneum over a dermis of fibroblasts in a collagen matrix were challenged with Dermatophagoides farinae, D. pteronyssinus and Euroglyphus maynei mite extracts. Results HSEs secreted interleukin (IL)-1?, IL-1 receptor antagonist, IL-6, IL-8, cutaneous T cell-attracting chemokine, transforming growth factor-?, granulocyte/macrophage and macrophage colony-stimulating factors and vascular endothelial cell growth factor in response to at least 1 mite extract. Extracts of different mite species stimulated HSEs to release different cytokines. Therefore, extracts of different species contained different molecules or different concentrations of similar molecules. The cytokine release profiles of cells in the HSEs were not the same as for monocultured keratinocytes and fibroblasts. Conclusions Molecules from house dust mites are capable of inducing the release of multiple proinflammatory cytokines and chemokines from epidermal keratinocytes and dermal fibroblasts. Avoiding skin contact with house dust mites would reduce the possibility of mite-induced inflammation in the skin. Therefore, measures to reduce contact with mite molecules such as frequent vacuuming of upholstered furniture and carpets and laundering of clothing and bedding to remove mite molecules and allergens could reduce skin contact with mite molecules and diminish exacerbations of skin inflammation in patients with atopic dermatitis and other skin diseases. PMID:21576987

  8. Comparative efficacy of house dust mite extermination products.

    PubMed

    Schober, G; Kniest, F M; Kort, H S; De Saint Georges Gridelet, D M; Van Bronswijk, J E

    1992-06-01

    The acaricidal efficacy of nine marketed products, i.e. Acardust, Acarosan (foam and powder), Actelic 50, Artilin 3A (spirit and water base), liquid nitrogen, Paragerm AK, and Tymasil, and of intensive vacuum-cleaning have been compared on four different test surfaces: mattress, tufted carpet, gypsum board and rough wooden board, all covered with artificial house dust. They were inoculated with the house dust mite, Dermatophagoides pteronyssinus or the house-dust fungus Aspergillus repens for evaluation of the fungistatic claims of some products. The acaricidal activity of Tymasil did not surpass that of vacuuming; its fungistatic effect was not apparent. The other products showed complete to almost complete eradication on at least one of the substrates tested. Taking into account the results of acaricidal efficacy as well as the data on safety and practicality acquired earlier, Acarosan powder was considered first choice for carpet treatment. Acarosan and liquid nitrogen, were found to be effective in the treatment of mattress, pillow, upholstered furniture and heavy curtains. On wooden surfaces Acarosan was found to be both effective and safe, while Acardust, Actelic 50, Artilin 3A (both fungistatic as well as acaricidal), liquid nitrogen and Paragerm also passed the efficiency test. PMID:1393759

  9. Quantification of C. globosum spores in house dust samples.

    PubMed

    Shi, Chunhua; Provost, Natacha B; Desroches, Tamara; Miller, J David

    2014-01-01

    Chaetomium globosum is one of the most common fungi that grows in damp buildings and occurs in agricultural and forestry workplaces. Using sera from atopic patients, we characterized and purified an extracellular chitosanase (Chg47) from C. globosum that is antigenic to humans. The study reports the production of monoclonal antibodies to the protein. Three capture ELISAs were developed for Chg47 for detection of spores and spore and mycelial fragments in dust samples using different mono- and polyclonal antibody combinations. One method is based on an enhanced biotinylated polyclonal antibody as the secondary antibody and coating anti-IgM to capture one of two clones of IgM monoclonal antibodies as the capture antibody. The other method makes use of an enhanced rabbit polyclonal antibody as both the primary and capture antibody. The detection limit of the double PAb method for the Chg47 antigen was 7.6 pg/ml. When the anti-IgM+10B3 clone was used, the detection limit was 61 pg/ml and for anti-IgM+5F12, 122 pg/ml. The detection limit of double PAb method is comparable to methods for the allergen and spores of Aspergillus versicolor in house dust and is more sensitive than other immunoassays for allergens in house including for Stachybotrys chartarum, Aspergillus fumigatus and Alternaria alternata. All three methods had limited cross-reactivity to fungi common in house dust representing a diverse array of taxa. PMID:25292122

  10. Monitoring and reducing exposure of infants to pollutants in house dust.

    PubMed

    Roberts, John W; Wallace, Lance A; Camann, David E; Dickey, Philip; Gilbert, Steven G; Lewis, Robert G; Takaro, Tim K

    2009-01-01

    The health risks to babies from pollutants in house dust may be 100 times greater than for adults. The young ingest more dust and are up to ten times more vulnerable to such exposures. House dust is the main exposure source for infants to allergens, lead, and PBDEs, as well as a major source of exposure to pesticides, PAHs, Gram-negative bacteria, arsenic, cadmium, chromium, phthalates, phenols, and other EDCs, mutagens, and carcinogens. Median or upper percentile concentrations in house dust of lead and several pesticides and PAHs may exceed health-based standards in North America. Early contact with pollutants among the very young is associated with higher rates of chronic illness such as asthma, loss of intelligence, ADHD, and cancer in children and adults. The potential of infants, who live in areas with soil contaminated by automotive and industrial emissions, can be given more protection by improved home cleaning and hand washing. Babies who live in houses built before 1978 have a prospective need for protection against lead exposures; homes built before 1940 have even higher lead exposure risks. The concentration of pollutants in house dust may be 2-32 times higher than that found in the soil near a house. Reducing infant exposures, at this critical time in their development, may reduce lifetime health costs, improve early learning, and increase adult productivity. Some interventions show a very rapid payback. Two large studies provide evidence that home visits to reduce the exposure of children with poorly controlled asthma triggers may return more than 100% on investment in 1 yr in reduced health costs. The tools provided to families during home visits, designed to reduce dust exposures, included vacuum cleaners with dirt finders and HEPA filtration, allergy control bedding covers, high-quality door mats, and HEPA air filters. Infants receive their highest exposure to pollutants in dust at home, where they spend the most time, and where the family has the most mitigation control. Normal vacuum cleaning allows deep dust to build up in carpets where it can be brought to the surface and become airborne as a result of activity on the carpet. Vacuums with dirt finders allow families to use the three-spot test to monitor deep dust, which can reinforce good cleaning habits. Motivated families that receive home visits from trained outreach workers can monitor and reduce dust exposures by 90% or more in 1 wk. The cost of such visits is low considering the reduction of risks achieved. Improved home cleaning is one of the first results observed among families who receive home visits from MHEs and CHWs. We believe that proven intervention methods can reduce the exposure of infants to pollutants in house dust, while recognizing that much remains to be learned about improving the effectiveness of such methods. PMID:19484587

  11. Associations between brominated flame retardants in house dust and hormone levels in men

    PubMed Central

    Johnson, Paula I.; Stapleton, Heather M.; Mukherjee, Bhramar; Hauser, Russ; Meeker, John D.

    2013-01-01

    Brominated flame retardants (BFRs) are used in the manufacture of a variety of materials and consumer products in order to meet fire safety standards. BFRs may persist in the environment and have been detected in wildlife, humans and indoor dust and air. Some BFRs have demonstrated endocrine and reproductive effects in animals, but human studies are limited. In this exploratory study, we measured serum hormone levels and flame retardant concentrations [31 polybrominated diphenyl ether (PBDE) congeners and 6 alternate flame retardants] in house dust from men recruited through a US infertility clinic. PBDE congeners in dust were grouped by commercial mixtures (i.e. penta-, octaand deca-BDE). In multivariable linear regression models adjusted by age and body mass index (BMI), significant positive associations were found between house dust concentrations of pentaBDEs and serum levels of free T4, total T3, estradiol, and sex hormone binding globulin (SHBG), along with an inverse association with follicle stimulating hormone (FSH). There were also positive associations of octaBDE concentrations with serum free T4, thyroid stimulating hormone (TSH), luteinizing hormone (LH) and testosterone and an inverse association of decaBDE concentrations with testosterone. Hexabromocyclododecane (HBCD) was associated with decreased SHBG and increased free androgen index. Dust concentrations of bis-tribromophenoxyethane (BTBPE) and tetrabromo-diethylhexylphthalate (TBPH) were positively associated with total T3. These findings are consistent with our previous report of associations between PBDEs (BDE 47, 99 and 100) in house dust and hormone levels in men, and further suggest that exposure to contaminants in indoor dust may be leading to endocrine disruption in men. PMID:23333513

  12. Application of Synchrotron Microprobe Methods to Solid-Phase Speciation of Metals and Metalloids in House Dust

    SciTech Connect

    S Walker; H Jamieson; P Rasmussen

    2011-12-31

    Determination of the source and form of metals in house dust is important to those working to understand human and particularly childhood exposure to metals in residential environments. We report the development of a synchrotron microprobe technique for characterization of multiple metal hosts in house dust. We have applied X-ray fluorescence for chemical characterization and X-ray diffraction for crystal structure identification using microfocused synchrotron X-rays at a less than 10 {micro}m spot size. The technique has been evaluated by application to archived house dust samples containing elevated concentrations of Pb, Zn, and Ba in bedroom dust, and Pb and As in living room dust. The technique was also applied to a sample of soil from the corresponding garden to identify linkages between indoor and outdoor sources of metals. Paint pigments including white lead (hydrocerussite) and lithopone (wurtzite and barite) are the primary source of Pb, Zn, and Ba in bedroom dust, probably related to renovation activity in the home at the time of sampling. The much lower Pb content in the living room dust shows a relationship to the exterior soil and no specific evidence of Pb and Zn from the bedroom paint pigments. The technique was also successful at confirming the presence of chromated copper arsenate treated wood as a source of As in the living room dust. The results of the study have confirmed the utility of this approach in identifying specific metal forms within the dust.

  13. Reliability of spot test kits for detecting lead in household dust.

    PubMed

    Korfmacher, Katrina Smith; Dixon, Sherry

    2007-06-01

    There has been a long-standing need for a technique that can provide fast, accurate and precise results regarding the presence of hazardous levels of lead in settled house dust. Several home testing kits are now available. One kit manufactured by Hybrivet (LeadCheck Swabs) is advertised as able to detect lead dust levels that exceed the US Environmental Protection Agency's dust lead standard for floors (40 microg/ft(2)). The purpose of the study was to determine the ability of LeadCheck Swabs to instantly detect lead in dust above EPA's hazard standard. A trained risk assessor collected 200 LeadCheck Swab samples side-by-side with standard dust wipe samples. The result of the LeadCheck Swab (positive (pink or red) or negative (yellow to brown)) was compared with the laboratory results for the corresponding dust wipe (over or under 40 microg/ft(2)). The LeadCheck Swabs produced a false negative rate of 64% (95% confidence interval: 55%, 72%). The likelihood of a swab producing a false negative depended on substrate (painted or non-painted) and surface type (floor or sill). Changing the interpretation rule by classifying all swab colors except yellow as positive yielded lower false negative rates under some test conditions, but still produced high error rates. LeadCheck Swabs do not reliably detect levels of lead in dust above 40 microg/ft(2) using published methods under field conditions. Further research into alternate methodologies and interpretation guidance is needed to determine whether the swabs can be appropriately used by consumers and others to test homes for lead dust hazards. PMID:17434162

  14. Flame retardant associations between children's handwipes and house dust.

    PubMed

    Stapleton, Heather M; Misenheimer, John; Hoffman, Kate; Webster, Thomas F

    2014-12-01

    Polybrominated diphenyl ether (PBDE), flame retardants (FRs) have been ubiquitously detected at high concentrations in indoor environments; however, with their recent phase-out, more attention is being focused on measurements of exposure to alternative FRs such as organophosphate FRs (OPFRs). In our previous research, we found that PBDE residues measured on children's handwipes were a strong predictor of serum PBDE levels. Here we build upon this research to examine longitudinal changes in PBDEs in indoor dust and children's handwipes, and explore the associations between handwipes and dust for alternative FRs. Children from our previous study were re-contacted after approximately two years and new samples of indoor dust and handwipes were collected. PBDE dust-levels were significantly correlated between two different sampling rounds separated by two years; however, PBDE levels in handwipes were not correlated, perhaps suggesting that the sources of PBDEs remained relatively constant in the home, but that behavioral differences in children are changing with age and influencing handwipe levels. OPFRs [i.e. tris(1,3-dichloroisopropyl) phosphate (TDCPP), tris(2-chloroethyl) phosphate (TCEP), tris(2-chloroisopropyl) phosphate (TCIPP)], 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EH-TBB, also known as TBB), di(2-ethylhexyl) tetrabromophthalate (BEH-TEBP, also known as TBPH), and 1,2,5,6,9,10-hexabromocyclododecane (HBCD) were also ubiquitously detected in house dust samples and geometric mean levels were similar to PBDE levels, or higher in the case of the OPFRs. Significant associations between handwipes and house dust were observed for these alternative FRs, particularly for EH-TBB (rs=0.54; p<0.001). Increasing house dust levels and age were associated with higher levels of FRs in handwipes, and high hand washing frequency (>5 times d(-1)) was associated with lower FR levels in handwipes. Overall these data suggest that exposure to these alternative FRs will be similar to PBDE exposure, and the influence of hand-to-mouth behavior in children's exposure needs to be further examined to better estimate exposure potential. PMID:24485814

  15. How relevant are house dust mite-fungal interactions in laboratory culture to the natural dust system?

    PubMed

    Hay, D B; Hart, B J; Pearce, R B; Kozakiewicz, Z; Douglas, A E

    1992-11-01

    Both house dust and house dust mites Dermatophagoides pteronyssinus contained a wider range of fungi than laboratory mite cultures. In total, nine species of fungi were isolated from D. pteronyssinus in house dust, and these included three xerophilic species (Eurotium amstelodami, Aspergillus penicillioides and Wallemia sebi) commonly found in laboratory cultures of D. pteronyssinus. It is concluded that mites do interact with a similar range of fungi in natural dust and in laboratory culture, but that the diversity of fungal species in the laboratory is reduced and the density of individual fungal species in culture exceeds that of house dust. In a second experiment, dust samples were incubated at room temperature with 75% relative humidity. The diversity of fungi invariably declined from up to 13 genera to the few species recorded in laboratory culture. This suggests that the dominance of xerophilic fungi in laboratory mite rearings is mediated primarily by low relative humidity, and the exclusion of air-borne spores. PMID:1493747

  16. Achieving dust lead clearance standards after lead hazard control projects: An evaluation of the HUD-recommended cleaning procedure and an abbreviated alternative

    Microsoft Academic Search

    S. Dixon; E. Tohn; R. Rupp; S. Clark

    1999-01-01

    The US Department of Housing and Urban Development's (HUD's) Guidelines for the Evaluation and Control of Lead-Based Paint Hazards in Housing strongly recommend that after lead hazard control interventions all walls, ceiling, floors, and other horizontal surfaces be cleaned using a three-step process to reduce lead-contaminated dust and debris. The three steps are: an initial vacuuming using a machine equipped

  17. MITE ANTIGEN CONCENTRATIONS IN HOUSE DUST AND THE OCCURRENCE OF WHEEZING IN CHILDREN WITH MITE DUST ALLERGY

    EPA Science Inventory

    We studied the relationship between dust mite antigen concentrations in house dust samples and the occurrence and frequency of wheezing in 58 children with dust mite allergy (wheal > 4 mm. mean diameter in response to a prick test with either D-. farinae or D pteronyssinus antige...

  18. Lead and zinc dust depositions from ore trains characterised using lead isotopic compositions.

    PubMed

    Kristensen, L J; Taylor, M P; Morrison, A L

    2015-03-11

    This study investigates an unusual source of environmental lead contamination - the emission and deposition of lead and zinc concentrates along train lines into and out of Australia's oldest silver-lead-zinc mine at Broken Hill, Australia. Transport of lead and zinc ore concentrates from the Broken Hill mines has occurred for more than 125 years, during which time the majority was moved in uncovered rail wagons. A significant amount of ore was lost to the adjoining environments, resulting in soil immediately adjacent to train lines elevated with concentrations of lead (695 mg kg(-1)) and zinc (2230 mg kg(-1)). Concentrations of lead and zinc decreased away from the train line and also with depth shown in soil profiles. Lead isotopic compositions demonstrated the soil lead contained Broken Hill ore in increasing percentages closer to the train line, with up to 97% apportioned to the mined Broken Hill ore body. SEM examination showed ceiling dusts collected from houses along the train line were composed of unweathered galena particles, characteristic of the concentrate transported in the rail wagons. The loss of ore from the uncovered wagons has significantly extended the environmental footprint of contamination from local mining operations over an area extending hundreds of kilometres along each of the three train lines. PMID:25627173

  19. Aspergillus penicilloides and Eurotium halophilicum in association with house-dust mites.

    PubMed

    Samson, R A; van der Lustgraaf, B

    1978-09-01

    Aspergillus penicilloides Speg., Eurotium halophilicum Christensen et al. and other xerophilic fungi were isolated from house dust. The isolates of E. halophilicum are described and compared with the type strain of this species. A. penicilloides appeared to be rather common. The species concept of this species is broadened to accomodate some variable forms with different colony characters and conidophore structures. The role of both species is discussed in connection with house-dust mites, house-dust allergy and skin diseases. PMID:714145

  20. Achieving dust lead clearance standards after lead hazard control projects: An evaluation of the HUD-recommended cleaning procedure and an abbreviated alternative

    SciTech Connect

    Dixon, S. (National Center for Lead-Safe Housing, Columbia, MD (United States)); Tohn, E. (ERT Associates, Montpelier, VT (United States)); Rupp, R. (Vermont Housing and Conservation Board, Chevy Chase, MD (United States)); Clark, S. (Univ. of Cincinnati, OH (United States). Dept. of Environmental Health)

    1999-05-01

    The US Department of Housing and Urban Development's (HUD's) Guidelines for the Evaluation and Control of Lead-Based Paint Hazards in Housing strongly recommend that after lead hazard control interventions all walls, ceiling, floors, and other horizontal surfaces be cleaned using a three-step process to reduce lead-contaminated dust and debris. The three steps are: an initial vacuuming using a machine equipped with a high-efficiency particulate air (HEPA) filter (HEPA vacuum), wet wash with a lead cleaner, and a final HEPA vacuum. This study evaluated the effectiveness of two cleaning protocols: (1) the HUD-recommended three-step procedure, and (2) an abbreviated two-step cleaning procedure that omits the final HEPA vacuum. Cleaning procedures were evaluated in 27 dwelling units that had undergone significant lead hazard control interventions likely to produce lead dust. Dust lead samples were collected on floors and in window sills and troughs prior to the lead control hazard intervention, after the wet wash step of the cleaning procedure, and after completion of the second HEPA vacuuming. The results of the study demonstrate that dust lead surface loading on smooth and cleanable surfaces following the three-step and two-step cleaning procedures can achieve 1995 federal guidance dust clearance levels and levels substantially lower. Although the dust lead clearance rates before and after the second HEPA vacuum were the same, the time saved by omitting the second HEPA is small relative to the other elements of the cleaning process.

  1. Lead poisoning

    MedlinePLUS

    ... problem. Lead is everywhere, including dirt, dust, new toys, and old house paint. Unfortunately, you can't ... paint chips or dust from lead-based paint. Toys and furniture painted before 1976. Painted toys and ...

  2. Associations between bacterial communities of house dust and infant gut.

    PubMed

    Konya, T; Koster, B; Maughan, H; Escobar, M; Azad, M B; Guttman, D S; Sears, M R; Becker, A B; Brook, J R; Takaro, T K; Kozyrskyj, A L; Scott, J A

    2014-05-01

    The human gut is host to a diverse and abundant community of bacteria that influence health and disease susceptibility. This community develops in infancy, and its composition is strongly influenced by environmental factors, notably perinatal anthropogenic exposures such as delivery mode (Cesarean vs. vaginal) and feeding method (breast vs. formula); however, the built environment as a possible source of exposure has not been considered. Here we report on a preliminary investigation of the associations between bacteria in house dust and the nascent fecal microbiota from 20 subjects from the Canadian Healthy Infant Longitudinal Development (CHILD) Study using high-throughput sequence analysis of portions of the 16S rRNA gene. Despite significant differences between the dust and fecal microbiota revealed by Nonmetric Multidimensional Scaling (NMDS) analysis, permutation analysis confirmed that 14 bacterial OTUs representing the classes Actinobacteria (3), Bacilli (3), Clostridia (6) and Gammaproteobacteria (2) co-occurred at a significantly higher frequency in matched dust-stool pairs than in randomly permuted pairs, indicating an association between these dust and stool communities. These associations could indicate a role for the indoor environment in shaping the nascent gut microbiota, but future studies will be needed to confirm that our findings do not solely reflect a reverse pathway. Although pet ownership was strongly associated with the presence of certain genera in the dust for dogs (Agrococcus, Carnobacterium, Exiguobacterium, Herbaspirillum, Leifsonia and Neisseria) and cats (Escherichia), no clear patterns were observed in the NMDS-resolved stool community profiles as a function of pet ownership. PMID:24637181

  3. Cigarette Smoke Potentiates House Dust Mite Allergen-Induced Increase in the Permeability of Human Bronchial Epithelial Cells In Vitro

    Microsoft Academic Search

    Csaba Rusznak; Raymond J. Sapsford; Jagdish L. Devalia; R. Justin John; Ellen L. Hewitt; Alan G. Lamont; Alan J. Wood; Samir S. Shah; Robert J. Davies; Stefan Lozewicz

    Although studies have suggested that exposure to cigarette smoke (CS) may be associated with the devel- opment of atopy, the mechanisms underlying this are not clearly understood. It has been suggested that CS impairs the barrier function of the airway epithelium, leading to increased access of allergens such as those of the house dust mite (HDM) Dermatophagoides pteronyssinus ( Der

  4. A NEW HOUSE DUST COLLECTION SYSTEM AND ITS USE IN A STUDY OF ASTHMA IN DUST MITE SENSITIVE CHILDREN IN RALEIGH, NORTH CAROLINA

    EPA Science Inventory

    A prototype dust collection system, the House Dust Vacuum One (HDVI), was designed for use in a study to investigate the relationship between house dust mite antigen levels and the presence of asthma in dust mite sensitive children. The HDVI was designed for the collection of dus...

  5. House dust mite allergen avoidance and self-management in allergic patients with asthma: randomised controlled trial

    PubMed Central

    de Vries, Marjolein P; van den Bemt, Lisette; Aretz, Karen; Thoonen, Bart PA; Muris, Jean WM; Kester, Arnold DM; Cloosterman, Sonja; van Schayck, CP Onno

    2007-01-01

    Background The efficacy of bed covers that are impermeable to house dust mites has been disputed. Aim The aim of the present study was to investigate whether the combination of ‘house dust mite impermeable’ covers and a self-management plan, based on peak flow values and symptoms, leads to reduced use of inhaled corticosteroids (ICS) than self-management alone. Design of study Prospective, randomised, double blind, placebo-controlled trial. Setting Primary care in a south-eastern region of the Netherlands. Method Asthma patients aged between 16 and 60 years with a house dust mite allergy requiring ICS were randomised to intevention and placebo groups. They were trained to use a self-management plan based on peak flow and symptoms. After a 3-month training period, the intervention commenced using house dust mite impermeable and placebo bed covers. The follow-up period was 2 years. Primary outcome was the use of ICS; secondary outcomes were peak expiratory flow parameters, asthma control, and symptoms. Results One hundred and twenty-six patients started the intervention with house dust mite impermeable or placebo bed covers. After 1 and 2 years, significant differences in allergen exposure were found between the intervention and control groups (P<0.001). No significant difference between the intervention and control groups was found in the dose of ICS (P = 0.08), morning peak flow (P = 0.52), peak flow variability (P = 0.36), dyspnoea (P = 0.46), wheezing (P = 0.77), or coughing (P = 0.41). There was no difference in asthma control between the intervention and control groups. Conclusion House dust mite impermeable bed covers combined with self-management do not lead to reduced use of ICS compared with self-management alone. PMID:17359604

  6. House dust mite and cat allergen in different indoor environments.

    PubMed

    Custovic, A; Taggart, S C; Woodcock, A

    1994-12-01

    Allergy to house dust mites (HDM) and domestic pets is a major cause of asthma. People in developed countries spend more than 90% of their time indoors. We have measured levels of HDM allergen Der pI and cat allergen Fel dI in public buildings and public transport. Dust samples were collected by vacuuming a 1 m2 area for 2 min from five schools, six hotels, four cinemas, six pubs, three buses, two trains and 12 domestic households without a cat. Der pI and Fel dI were assayed with monoclonal antibodies in a two-site immunometric ELISA. Der pI concentration was significantly higher in the private homes than in comparable sites in public places except for cinema seats (where high values were found) compared with domestic sofas. Der pI > 2000 ng/g of fine dust was found in 30% of the upholstered seats, 9% having a concentration > 10,000 ng/g. Fel dI levels were significantly higher in the dust from upholstered seats (geometric mean 14.88 micrograms/g) than in carpeted floors (geometric mean 0.73 micrograms/g), and in public places than in private homes. Fel dI > 8 micrograms/g was found in 79% of the upholstered seats or furniture sampled in public buildings or public transport. In conclusion, upholstered seats from public buildings and public transport constitute an allergen reservoir for continuous contamination of the indoor environment which could compromise the effects of allergen avoidance employed at home. PMID:7889431

  7. Reducing relative humidity to control the house dust mite Dermatophagoides farinae

    Microsoft Academic Search

    Larry G. Arlian; Jacqueline S. Neal; DiAnn L. Vyszenski-Moher

    1999-01-01

    Background: Indoor relative humidity (RH) is the key factor that determines the survival and population development of the house dust mite Dermatophagoides farinae . Maintaining RH below 50% is one recommendation in a comprehensive plan to reduce house dust mites and mite allergen levels in homes. Even when mean daily RH is reduced below 50%, RH may rise above 50%

  8. Human Exposure to PBDEs Via House Dust Ingestion in Guangzhou, South China

    Microsoft Academic Search

    Laiguo Chen; Yumei Huang; Zhencheng Xu; Lijun Wen; Xiaochun Peng; Zhixiang Ye; Sukun Zhang; Xiang-Zhou Meng

    2011-01-01

    Numerous studies have demonstrated the important role played by indoor dust in human exposure to polybrominated diphenyl ethers\\u000a (PBDEs), particularly in children, who spend most of their time indoors. Few data have been available for PBDEs in house dust\\u000a in China. In this study, dust samples were collected randomly from 46 houses in Guangzhou, South China, for the first time

  9. Testing your home for lead in paint, dust, and soil

    SciTech Connect

    NONE

    1998-10-01

    This publication is for anyone who is considering having a home or residence tested for lead in paint, dust, or soil by a professional. It explains the technical aspects of lead testing without overwhelming the reader. The first section tells why you would test for lead, the approaches for testing for lead, and what information you will get from each approach. The second section answers specific questions about how paint, soil, and dust sampling are conducted by the professional in your home. Finally, the last section answers other questions about testing, including questions about home test kits and testing of water and ceramics.

  10. Characterization of Brominated Flame Retardants in House Dust and Their Role as Non-Dietary Source for Human in Indonesia

    Microsoft Academic Search

    Agus SUDARYANTO; Tomohiko ISOBE; Go SUZUKI; Iwan Eka SETIAWAN; Muhammad ILYAS; Adi Slamet RIYADI; Shin TAKAHASHI; Shinsuke TANABE

    The present study determined the levels of polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs) and compared them with the levels of polychlorinated biphenyls (PCBs) in house dust and other environmental media from Indonesia, aiming at characterization of these compounds in house dust and the role of house dust as a human non-dietary exposure. PBDEs and HBCDs were detected in all

  11. 35. BOILER HOUSE, TRACK FOR COAL CARS LEADING TO COAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    35. BOILER HOUSE, TRACK FOR COAL CARS LEADING TO COAL TOWER No. 2 (NOTE: SKYLIGHT ABOVE; COAL CARS IN FAR BACKGROUND) - Delaware County Electric Company, Chester Station, Delaware River at South end of Ward Street, Chester, Delaware County, PA

  12. 39. BOILER HOUSE, COAL CONVEYOR LEADING FROM COAL TOWER No. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    39. BOILER HOUSE, COAL CONVEYOR LEADING FROM COAL TOWER No. 1 (WEST) (NOTE: COAL CARS No. 9 & 5 IN BACKGROUND) - Delaware County Electric Company, Chester Station, Delaware River at South end of Ward Street, Chester, Delaware County, PA

  13. Polychlorinated biphenyls in house dust and yard soil near a Superfund site

    SciTech Connect

    Vorhees, D.J.; Altshul, L.M. [Harvard School of Public Health, Boston, MA (United States)] [Harvard School of Public Health, Boston, MA (United States); Cullen, A.C. [Harvard School of Public Health, Boston, MA (United States)] [Harvard School of Public Health, Boston, MA (United States); [Univ. of Washington, Seattle, WA (United States)

    1999-07-01

    Polychlorinated biphenyls (PCBs) were measured in house dust and yard soil at 34 homes surrounding New Bedford Harbor during dredging of highly contaminated harbor sediments. PCBs can volatilize from sediments and seawater and subsequently deposit on surrounding soil, resulting in potential exposures for nearby residents. House dust was collected from carpet, while yard soil was collected from the main entryway to evaluate whether PCBs might be tracked indoors. All samples were analyzed for 65 PCB congeners to evaluate the relative importance of the harbor and indoor sources for human exposure. PCB concentrations in house dust were about 10 times higher than yard soil concentrations, although similar congener patterns were detected in these two media. Yard soil concentrations in neighborhoods closest to the harbor were significantly higher than those in comparison neighborhoods, while house dust concentrations did not different significantly between these two locales, PCB concentrations in house dust were correlated with those in indoor air, but house dust and yard soil concentrations were not correlated, suggesting that track-in may not be the only source of PCBs in house dust.

  14. CHILDHOOD BLOOD LEAD LEVELS NOT AFFECTED BY HOUSING COMPLIANCE STATUS

    EPA Science Inventory

    In a secondary analysis of data from the Childhood Lead Poisoning Prevention Program of Philadelphia (July 1, 1999 through September 1, 2004), the authors evaluated the effect of housing compliance status and time to achieve compliance on changes in children's blood lead levels. ...

  15. Summer Housing Contract INTRODUCTION

    E-print Network

    Devoto, Stephen H.

    are not identified. See Physical Pland Housing Guidelines for more detail. LEAD PAINT DISCLOSURE Housing built before 1978 may contain lead-based paint. Lead from paint, paint chips, and dust can pose health hazards renting pre-1978 housing, landlords must disclose the presence of known lead-based paint and lead

  16. METHODOLOGY FOR DETERMINATION OF POLYCYCLIC AROMATIC HYDROCARBONS AND OTHER SEMIVOLATILE ORGANIC COMPOUNDS IN HOUSE DUST

    EPA Science Inventory

    Analytical methods were validated to determine polycyclic aromatic hydrocarbons (PAH) and other semivolatile organic compounds in house dust. e also examined the storage stability of three potential markers (solanesol, nicotine, and continine) for particulate-phase environmental ...

  17. Aspergillus, Penicillium and Talaromyces isolated from house dust samples collected around the world

    E-print Network

    Amend, Anthony S.

    Aspergillus, Penicillium and Talaromyces isolated from house dust samples collected around Penicillium species of which seven were undescribed and 18 Talaromyces species including three described here, Penicillium alfredii Visagie, Seifert & Samson, P. dunedinense Visagie, Seifert & Samson, P. infrapurpureum

  18. DEVELOPMENT OF ANALYTICAL METHODS FOR SPECIFIC LAWN- APPLIED PESTICIDES IN HOUSE DUST

    EPA Science Inventory

    Many pesticides have been developed for residential outdoor application, particularly for lawn care. Residues from these applications may be tracked into the home, where they become incorporated with house dust and persist for long periods of time. Consequently, potential human...

  19. A HYDROTHERMAL MODEL FOR PREDICTING HOUSE-DUST MITE RESPONSE TO ENVIRONMENTAL CONDITIONS IN DWELLINGS

    Microsoft Academic Search

    N Bakerl

    House-dust mite antigens are a major contributor to allergic sensitisation. Since temperature and humidity are crucial to house-dust mite physiology, there is considerable interest in reducing mite populations by controlling the indoor environment. A multidisciplinary team of building scientists and entomologists has been formed to develop a prototype hydrothermal model that simulates the dynamic interaction between the mite's micro-environment within

  20. Prevention of House Dust Mite Induced Allergic Airways Disease in Mice through Immune Tolerance

    PubMed Central

    Agua-Doce, Ana; Graca, Luis

    2011-01-01

    Allergic airways disease is a consequence of a Th2 response to an allergen leading to a series of manifestations such as production of allergen-specific IgE, inflammatory infiltrates in the airways, and airway hyper-reactivity (AHR). Several strategies have been reported for tolerance induction to allergens leading to protection from allergic airways disease. We now show that CD4 blockade at the time of house dust mite sensitization induces antigen-specific tolerance in mice. Tolerance induction is robust enough to be effective in pre-sensitized animals, even in those where AHR was pre-established. Tolerant mice are protected from airways eosinophilia, Th2 lung infiltration, and AHR. Furthermore, anti-CD4 treated mice remain immune competent to mount immune responses, including Th2, to unrelated antigens. Our findings, therefore, describe a strategy for tolerance induction potentially applicable to other immunogenic proteins besides allergens. PMID:21818308

  1. Occurrence of Respiratory Symptoms Resulting from Exposure to House Dust Mites in Early Childhood

    ERIC Educational Resources Information Center

    Jedrychowski, Wieslaw; Maugeri, Umberto; Zembala, Marek; Hajto, Barbara; Flak, Elzbieta; Mroz, Elzbieta; Jacek, Ryszard; Sowa, Agata; Perera, Frederica P.

    2009-01-01

    The aim of the study was to describe the distribution of house dust mite (HDM) allergens within homes of three-year-old children, to identify factors responsible for its variation and to test the hypothesis whether the content of HDM allergens exceeding 2 [mu]g/g dust may be regarded as a risk level of sensitization possibly affecting respiratory…

  2. Development of a Simultaneous Extraction and Cleanup Method for Pyrethroid Pesticides from Indoor House Dust Samples

    EPA Science Inventory

    An efżcient and reliable analytical method was developed for the sensitive and selective quantiżcation of pyrethroid pesticides (PYRs) in house dust samples. The method is based on selective pressurized liquid extraction (SPLE) of the dust-bound PYRs into dichloromethane (DCM) wi...

  3. DISTRIBUTION OF PESTICIDES AND POLYCYCLIC AROMATIC HYDROCARBONS IN HOUSE DUST AS A FUNCTION OF PARTICLE SIZE

    EPA Science Inventory

    House dust is a repository for environmental pollutants that may accumulate indoors from both internal and external sources over long periods of time. Dust and tracked-in soil accumulate most efficiently in carpets, and the pollutants associated with it may present an exposure...

  4. Contamination of houses by workers occupationally exposed in a lead-zinc-copper mine and impact on blood lead concentrations in the families.

    PubMed Central

    Chiaradia, M; Gulson, B L; MacDonald, K

    1997-01-01

    OBJECTIVE: To evaluate the pathway of leaded dust from a lead-zinc-copper mine to houses of employees, and the impact on blood lead concentrations (PbB) of children. METHODS: High precision lead isotope and lead concentration data were obtained on venous blood and environmental samples (vacuum cleaner dust, interior dustfall accumulation, water, paint) for eight children of six employees (and the employees) from a lead-zinc-copper mine. These data were compared with results for 11 children from occupationally unexposed control families living in the same city. RESULTS: The median (range) concentrations of lead in vacuum cleaner dust was 470 (21-1300) ppm. In the houses of the mine employees, vacuum cleaner dust contained varying higher proportions of mine lead than did airborne particulate matter measured as dustfall accumulated over a three month period. The median (range) concentrations of lead in soil were 30 (5-407) ppm and these showed no evidence of any mine lead. Lead in blood of the mine employees varied from 7 to 25 micrograms/dl and was generally dominated by mine lead (> 60%). The mean (SD) PbB in the children of the mine employees was 5.7 (1.7) micrograms/dl compared with 4.1 (1.4) micrograms/dl for the control children (P = 0.02). The PbB of all children was always < 10 micrograms/dl, the Australian National Health and Medical Research Council goal for all Australians. Some of the control children had higher PbB than the children of mine employees, probably from exposure to leaded paint as six of the eight houses of the control children were > 50 years old. In five of the eight children of mine employees > 20% of PbB was from the lead mine. However, in the other three cases of children of mine employees, their PbB was from sources other than mine lead (paint, petrol, background sources). CONCLUSIONS: Houses of employees from a lead mine can be contaminated by mine lead even if they are not situated in the same place as the mine. Delineation of the mine to house pathway indicates that lead is probably transported into the houses on the clothes, shoes, hair, skin, and in some cases, motor vehicles of the workers. In one case, dust shaken from clothes of a mine employee contained 3000 ppm lead which was 100% mine lead. The variable contamination of the houses was not expected given the precautions taken by mine employees to minimise transportation of lead into their houses. Although five out of the eight children of mine employees had > 20% mine lead in their blood, in no case did the PbB of a child exceed the Australian National Health and Medical Research Council goal of 10 micrograms/dl. In fact, some children in the control families had higher PbB than children of mine employees. In two cases, this was attributed to a pica habit for paint. The PbB in the children of mine employees and controls was independent of the source of lead. The low PbB in the children of mine employees may reflect the relatively low solubility (bioavailability) of the mine dust in 0.1 M hydrochloric acid (< 40 %), behaviour--for example, limited mouthing activity--or diet. PMID:9072019

  5. House dust mite ( Dermatophagoides farinae and Dermatophagoides pteronyssinus) prevalence in the rooms and hallways of a tertiary care hospital

    Microsoft Academic Search

    Kenneth S. Babe; Larry G. Arlian; Patricia D. Confer; Richard Kim

    1995-01-01

    Background: House dust mites, Dermatophagoides farinae and Dermatophagoides pteronyssinus, are important components in the development of asthma. Objective: We measured the prevalence of house dust mites in a tertiary care hospital located in a temperate geographic region where dust mites were prevalent in homes. Methods: The density of Dermatophagoides spp. was measured in hospital hallways, carpeted patients' rooms, and noncarpeted

  6. Protective effect of the DNA vaccine encoding the major house dust mite allergens on allergic inflammation in the murine model of house dust mite allergy

    Microsoft Academic Search

    Nacksung Kim; Soon Seog Kwon; Jaechun Lee; Sohyung Kim; Tai June Yoo

    2006-01-01

    BACKGROUND: Vaccination with naked DNA encoding antigen induces cellular and humoral immunity characterized by the activation of specific Th1 cells. OBJECTIVE: To evaluate the effects of vaccination with mixed naked DNA plasmids encoding Der p 1, Der p 2, Der p 3, Der f 1, Der f 2, and Der f 3, the major house dust mite allergens on the

  7. FIELD DEMONSTRATION OF LEAD PAINT ABATEMENT TECHNOLOGIES IN RESIDENTIAL HOUSING

    EPA Science Inventory

    This study was conducted to demonstrate lead-based paint (LBP) removal from architectural wood components in CO2 unoccupied residential housing using four technologies: granular carbon dioxide (CO2 blasting), pelletized CO2 blasting, encapsulant paint remover, and wet abrasive bl...

  8. National evaluation of the US Department of Housing and Urban Development Lead-Based Paint Hazard Control Grant Program: Study methods

    Microsoft Academic Search

    Warren Galke; Scott Clark; Pat McLaine; Robert Bornschein; Jonathan Wilson; Paul Succop; Sandy Roda; Jill Breysse; David Jacobs; JoAnn Grote; William Menrath; Sherry Dixon; Mei Chen; Ralph Buncher

    2005-01-01

    The US Department of Housing and Urban Development (HUD) undertook an evaluation of its Lead Hazard Control Grant Program between 1994 and 1999. The Evaluation is the largest study ever done on the effectiveness of lead hazard controls implemented in residential dwellings. The Evaluation had several major objectives: determining the effectiveness of various lead hazard controls in reducing residential dust

  9. Application of neutral electrolyzed water spray for reducing dust levels in a layer breeding house.

    PubMed

    Zheng, Weichao; Li, Baoming; Cao, Wei; Zhang, Guoqiang; Yang, Zhanyong

    2012-11-01

    Reducing airborne dust is an essential process for improving hen housing environment. Dust reduction effects of neutral electrolyzed water (pH 8.2) spray were investigated in a commercial tunnel-ventilated layer breeding house during production in northern China. A multipoint sampler was used to measure airborne dust concentration to study the dust reduction effects and distribution in the house. Compared with the control treatment (without spray), airborne dust level was reduced 34% in the 3 hr after spraying 216 mL m(-2) neutral electrolyzed water in the breeding house. The dust concentration was significantly higher during the periods of feed distribution (1.13 +/- 0.13 mg m(-3)) and artificial insemination (0.72 +/- 0.13 mg m(-3)) compared with after spray (0.47 +/- 0.09 mg m(-3)) and during lights-off period (0.29 +/- 0.08 mg m(-3)) in the three consecutive testing days (P <0.05). The experimental cage area was divided into four zones along the length of the house, with zone 1 nearest to the evaporative cooling pad and zone 4 nearest to the fans. The air temperature, relative humidity, airflow rate, and dust concentration were measured at the sampling points of the four zones in 3 consecutive days and mortality of the birds for the duration of a month were investigated. The results showed that the air temperature, airflow rate, dust concentration, and number of dead birds increase from zone 1 to zone 4 in the tunnel-ventilated layer breeding house. PMID:23210224

  10. Relationships between Polybrominated Diphenyl Ether Concentrations in House Dust and Serum

    PubMed Central

    Johnson, Paula I.; Stapleton, Heather M.; Sjodin, Andreas; Meeker, John D.

    2010-01-01

    Polybrominated diphenyl ethers (PBDEs) have been measured in the home environment and in humans, but studies linking environmental levels to body burdens are limited. This study examines the relationship between PBDE concentrations in house dust and serum from adults residing in these homes. We measured PBDE concentrations in house dust from 50 homes and in serum of male-female couples from 12 of the homes. Detection rates, dust-serum and within-matrix correlations varied by PBDE congener. There was a strong correlation (r = 0.65–0.89, p < 0.05) between dust and serum concentrations of several predominant PBDE congeners (BDE 47, 99 and 100). Dust and serum levels of BDE 153 were not correlated (r < 0.01). The correlation of dust and serum levels of BDE 209 could not be evaluated due to low detection rates of BDE 209 in serum. Serum concentrations of the sum of BDE 47, 99, and 100 were also strongly correlated within couples (r = 0.85, p = 0.0005). This study provides evidence that house dust is a primary exposure pathway of PBDEs and supports the use of dust PBDE concentrations as a marker for exposure to PBDE congeners other than BDE 153. PMID:20521814

  11. Polybrominated diphenyl ether (PBDE) concentrations in house dust are related to hormone levels in men

    PubMed Central

    Meeker, John D.; Johnson, Paula I.; Camann, David; Hauser, Russ

    2009-01-01

    Despite documented widespread human exposure to polybrominated diphenyl ethers (PBDEs) through dietary intake and contact or inhalation of indoor dust, along with growing laboratory evidence for altered endocrine function following exposure, human studies of PBDE exposure and endocrine effects remain limited. We conducted a preliminary study within an ongoing study on the impact of environmental exposures on male reproductive health. We measured serum hormone levels and PBDE concentrations (BDE 47, 99 and 100) in house dust from 24 men recruited through a US infertility clinic. BDE 47 and 99 were detected in 100% of dust samples, and BDE 100 was detected in 67% of dust samples, at concentrations similar to those reported in previous US studies. In multivariable regression models adjusted for age and BMI, there was a statistically significant inverse relationship between dust PBDE concentrations and free androgen index. Dust PBDE concentrations were also strongly and inversely associated with luteinizing hormone (LH) and follicle stimulating hormone (FSH), and positively associated with inhibin B and sex hormone binding globulin (SHBG). Finally, consistent with limited recent human studies of adults, PBDEs were positively associated with free T4. In conclusion, the present study provides compelling evidence of altered hormone levels in relation to PBDE exposures estimated as concentrations in house dust, and that house dust is an important source of human PBDE exposure, but more research is urgently needed. PMID:19211133

  12. Enhanced expression of B7.2 (CD86) by percutaneous sensitization with house dust mite antigen

    Microsoft Academic Search

    Kazuki Santa; Kenji Watanabe; Tsutomu Nakada; Hiroyuki Kato; Sonoko Habu; Shunichiro Kubota

    2003-01-01

    House dust mite antigen is a well-known allergen in the pathogenesis of atopic dermatitis (AD), a chronic relapsing inflammatory skin disease. We evaluated the AD model mice sensitized with house dust mite antigen and observed a Th2-dominant immune response. In this experiment, BALB\\/c mice were sensitized percutaneously with house dust mite antigen three times with 7 days interval after skin

  13. Elemental composition of airborne dust in the Shale Shaker House during an offshore drilling operation.

    PubMed

    Hansen, A B; Larsen, E; Hansen, L V; Lyngsaae, M; Kunze, H

    1991-12-01

    During 2 days of an offshore drilling operation in the North Sea, 16 airborne dust samples from the atmosphere of the Shale Shaker House were collected onto filters. During this operation, drilling mud composed of a water slurry of barite (BaSO4) together with minor amounts of additives, among them chrome lignosulphonate and chrome lignite, was circulated between the borehole and the Shale Shaker House. The concentration of airborne dust in the atmosphere was determined and the elemental composition of the particles analysed by both PIXE (proton-induced X-ray emission) and ICP-MS (inductively coupled plasma-mass spectrometry). The total amount of dust collected varied from 0.04 to 1.41 mg m-3 with barium (Ba) as the single most abundant element. The open shale shakers turned out to be the major cause of generation of dust from the solid components of the drilling mud. PMID:1768013

  14. Investigating A Novel Flame Retardant Known as V6: Measurements in Baby Products, House Dust and Car Dust

    PubMed Central

    Fang, Mingliang; Webster, Thomas F.; Gooden, David; Cooper, Ellen M.; McClean, Michael D.; Carignan, Courtney; Makey, Colleen; Stapleton, Heather M.

    2013-01-01

    With the phase-out of polybrominated diphenyl ether (PBDE) flame retardants, the use of new and alternate flame retardants has been increasing. 2,2-bis(chloromethyl)propane-1,3-diyltetrakis(2-chloroethyl) bisphosphate, known as V6, is a flame retardant applied to polyurethane foam commonly found in furniture and automobile foam. However, to the authors’ knowledge, no research has been conducted on V6 levels in the environment. The intention of this study was to measure the concentration of V6 in foam collected from baby products where it was recently detected, and measure levels in dust samples collected from homes and automobiles in the Boston, MA area. To accomplish this a pure V6 commercial standard was purchased from a Chinese manufacturer and purified (> 98%). An analytical method to measure V6 in dust samples using liquid chromatography tandem mass spectrometry (LC/MS-MS) was developed. Extraction was conducted using Accelerated Solvent Extraction (ASE) and extracts were purified using an ENVI-Florisil SPE column (500 mg, 3mL). V6 was measured in foam samples collected from baby products with a concentration ranging from 24,500,000 to 59,500,000 ng/g of foam (n = 12, average ± sd: 46,500,000 ± 12,000,000 ng/g; i.e., on average, 4.6 % of the foam mass was V6). V6 was also detected in 19 of 20 car dust samples and 14 of 20 house dust samples analyzed. The concentration of V6 in the house dust ranged from < 5 ng/g to 1,110 ng/g with a median of 12.5 ng/g, and < 5 ng/g to 6,160 ng/g in the car dust with a median of 103.0 ng/g. Concentrations in car dust were significantly higher than the house dust, potentially indicating higher use of V6 in automobiles compared to products found in the home. Furthermore, tris (2-chloroethyl) phosphate (TCEP), a known carcinogen, was found in the V6 commercial mixture (14% by weight) as an impurity and was consistently detected with V6 in the foam samples analyzed. A significant correlation was also observed between V6 and TCEP in the dust samples, suggesting that the use of V6 is a significant source of TCEP in the indoor environment. PMID:23565680

  15. Investigating a novel flame retardant known as V6: measurements in baby products, house dust, and car dust.

    PubMed

    Fang, Mingliang; Webster, Thomas F; Gooden, David; Cooper, Ellen M; McClean, Michael D; Carignan, Courtney; Makey, Colleen; Stapleton, Heather M

    2013-05-01

    With the phase-out of polybrominated diphenyl ether (PBDE) flame retardants, the use of new and alternate flame retardants has been increasing. 2,2-bis(chloromethyl)propane-1,3-diyltetrakis(2-chloroethyl) bisphosphate, known as V6, is a flame retardant applied to polyurethane foam commonly found in furniture and automobile foam. However, to the authors' knowledge, no research has been conducted on V6 levels in the environment. The intention of this study was to measure the concentration of V6 in foam collected from baby products where it was recently detected and measure levels in dust samples collected from homes and automobiles in the Boston, MA area. To accomplish this, a pure V6 commercial standard was purchased from a Chinese manufacturer and purified (>98%). An analytical method to measure V6 in dust samples using liquid chromatography tandem mass spectrometry (LC/MS-MS) was developed. Extraction was conducted using accelerated solvent extraction (ASE) and extracts were purified using an ENVI-Florisil SPE column (500 mg, 3 mL). V6 was measured in foam samples collected from baby products with a concentration ranging from 24,500,000 to 59,500,000 ng/g of foam (n = 12, average ± sd: 46,500,000 ± 12,000,000 ng/g; i.e., on average, 4.6% of the foam mass was V6). V6 was also detected in 19 of 20 car dust samples and 14 of 20 house dust samples analyzed. The concentration of V6 in the house dust ranged from <5 ng/g to 1110 ng/g with a median of 12.5 ng/g, and <5 ng/g to 6160 ng/g in the car dust with a median of 103.0 ng/g. Concentrations in car dust were significantly higher than in the house dust potentially indicating higher use of V6 in automobiles compared to products found in the home. Furthermore, tris (2-chloroethyl) phosphate (TCEP), a known carcinogen, was found in the V6 commercial mixture (14% by weight) as an impurity and was consistently detected with V6 in the foam samples analyzed. A significant correlation was also observed between V6 and TCEP in the dust samples suggesting that the use of V6 is a significant source of TCEP in the indoor environment. PMID:23565680

  16. Cross-Antigenicity Between the Scabies Mite, Sarcoptes scabiei, and the House Dust Mite, Dermatophagoides pteronyssinus

    Microsoft Academic Search

    Larry G. Arlian; Diann L. Vyszenski-Moher; Salva G. Ahmed; Stephen A. Estes

    1991-01-01

    This study demonstrated that antigens of the parasitic mite Sarcoptes scabiei (SS) cross-react with antigens of the house dust mite Dermatophagoides pteronyssinus(DP). Crossed immunoelectrophoresis (CE) reaction of SS extract with rabbit anti-DP serum resulted in multiple immunoprecipitates. Reciprocal CIE reactions gave similar results. Immunoprecipitates from both reactions bound IgE in the sera of dust-mite – sensitive patients who had no

  17. Replicating the cross-sectional distribution of house-dust mite allergen found in carpet

    Microsoft Academic Search

    S. M. Causer; C. Piper; C. L. Shorter; R. D. Lewis

    2010-01-01

    With a view to producing carpets that could be used to determine the ease of particulate aerosolisation during domestic activity, we measured the cross-sectional distribution of dust-mite allergen, Der p 1, produced using American Society for Testing and Materials method (ASTM F608–89) for embedding house dust in carpets with that produced by several alternative protocols. Allergen concentrations produced at different

  18. Characterization of fungal communities in house dust samples collected from central Portugal-a preliminary survey.

    PubMed

    Sousa, Ana C A; Almeida, Joana R S L; Pereira, Cristiana C; Ramiro Pastorinho, M; Pereira, Ângela M C; Nogueira, António J A; Taborda-Barata, Luís; Teixeira, Joăo P; Correia, António C M; Alves, Artur

    2014-01-01

    House dust is a repository and concentrator of many chemical and biological agents including fungi. Considering that dust acts as a long-term reservoir of airborne fungi and that cumulative exposure is more relevant to potential health problems than single-day or short-term exposure, characterization of fungal communities in dust samples is of paramount importance. In the present study, the fungal composition of Portuguese house dust samples was determined. A total of 28 samples were obtained from vacuum cleaner deposits from households located in central Portugal. DNA was extracted from dust samples and fungal communities were analyzed using a culture-independent polymerase chain reaction (PCR)- denaturing gradient gel electrophoresis (DGGE) approach. Cultural analyses were also performed in order to identify the viable fungi species present in selected samples. Fungal diversity, reported as the number of operational taxonomic units (OTU), varied between 9 and 56 OTU. This analysis of viable fungi showed that Aspergillus was the most abundant genus, followed by Penicillium, Mucor, and Rhizomucor. Trichoderma, Chrysosporium, Fusarium, Rhizopus, and Stachybotrys were found in a limited number of houses. Our results demonstrated that dust is, in fact, home for a diverse and heterogeneous fungal community and that some of the species found are known allergic agents with severe negative impacts on human health. PMID:25072728

  19. A survey of spatially distributed exterior dust lead loadings in New York City

    SciTech Connect

    Caravanos, Jack [Hunter College-CUNY, School of Health Sciences (United States); Weiss, Arlene L. [Environmental Medicine Inc., 263 Center Avenue, Westwood, NJ 07675 (United States); School of Medicine, New York University, NY 10016 (United States); Blaise, Marc J. [Hunter College-CUNY, School of Health Sciences (United States); Jaeger, Rudolph J. [Environmental Medicine Inc., 263 Center Avenue, Westwood, NJ 07675 (United States) and School of Medicine, New York University, NY 10016 (United States)]. E-mail: jaegerr@envmed.com

    2006-02-15

    This work documents ambient lead dust deposition values (lead loading) for the boroughs of New York City in 2003-2004. Currently, no regulatory standards exist for exterior concentrations of lead in settled dust. This is in contrast to the clearance and risk assessment standards that exist for interior residential dust. The reported potential for neurobehavioral toxicity and adverse cognitive development in children due to lead exposure prompts public health concerns about undocumented lead sources. Such sources may include settled dust of outdoor origin. Dust sampling throughout the five boroughs of NYC was done from the top horizontal portion of pedestrian traffic control signals (PTCS) at selected street intersections along main thoroughfares. The data (n=214 samples) show that lead in dust varies within each borough with Brooklyn having the highest median concentration (730{mu}g/ft{sup 2}), followed in descending order by Staten Island (452{mu}g/ft{sup 2}), the Bronx (382{mu}g/ft{sup 2}), Queens (198{mu}g/ft{sup 2}) and finally, Manhattan (175{mu}g/ft{sup 2}). When compared to the HUD/EPA indoor lead in dust standard of 40{mu}g/ft{sup 2}, our data show that this value is exceeded in 86% of the samples taken. An effort was made to determine the source of the lead in the dust atop of the PTCS. The lead in the dust and the yellow signage paint (which contains lead) were compared using isotopic ratio analysis. Results showed that the lead-based paint chip samples from intact signage did not isotopically match the dust wipe samples taken from the same surface. We know that exterior dust containing lead contributes to interior dust lead loading. Therefore, settled leaded dust in the outdoor environment poses a risk for lead exposure to children living in urban areas, namely, areas with elevated childhood blood lead levels and background lead dust levels from a variety of unidentified sources.

  20. Nitric oxide metabolites in nasal lavage fluid of patients with house dust mite allergy

    Microsoft Academic Search

    I M Garrelds; J G van Amsterdam; C de Graaf-in't Veld; R Gerth van Wijk; F J Zijlstra

    1995-01-01

    BACKGROUND--The role of nitric oxide in the early and late phase of the allergic process was investigated in patients with allergic rhinitis against house dust mite and the effect of fluticasone propionate aqueous nasal spray was determined. METHODS--Production of nitric oxide (measured as nitrite+nitrate) in vivo in nasal mucosa was examined in 24 patients with rhinitis allergic to the house

  1. CONTROLLING HOUSE DUST MITES THROUGH VENTILATION: the development of a model of mite response to varying hygrothermal conditions

    Microsoft Academic Search

    D Crowther; T Oreszczyn; S Pretlove; I Ridley; J Horwood; P Cox; B Leung

    There is clear evidence that house dust mite populations in many climatic regions can potentially be controlled by modifying temperature and humidity within dwellings. This paper describes a current multi-disciplinary UK funded research project to develop a predictive model of house dust mite response to varying hygrothermal conditions. The project involves the development of two component models, the first simulating

  2. A Major House Dust Mite Allergen Disrupts the Immunoglobulin E Network by Selectively Cleaving CD23: Innate Protection by Antiproteases

    Microsoft Academic Search

    Colin R. A. Hewitt; Alan R Brown; Barbara J. Hart; David I. Pritchard

    1995-01-01

    SumlTlary Asthma is a chronic life-threatening disease of worldwide importance. Although allergic asthma and related atopic conditions correlate strongly with immune sensitization to house dust mites, it is unclear why antigens from mites provoke such powerful allergic immune responses. We have characterized the protease activity of Der p I, the group I protease allergen of the house dust mite Dermatophagoides

  3. APPLICATION OF AN ELECTROSTATIC SPACE CHARGE SYSTEM FOR DUST, AMMONIA AND PATHOGEN REDUCTION IN A BROILER BREEDER HOUSE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Airborne dust in poultry housing is known to be one of the primary means by which disease causing organisms are spread throughout a house. Reductions in airborne dust levels have been associated with even greater reductions in airborne bacteria. An electrostatic space charge system (ESCS) was used o...

  4. Organophosphorus flame retardants (PFRs) and plasticizers in house and car dust and the influence of electronic equipment.

    PubMed

    Brandsma, Sicco H; de Boer, Jacob; van Velzen, Martin J M; Leonards, Pim E G

    2014-12-01

    All nine PFRs studied were detected in house and car dust from the Netherlands with the exception of tris(butyl) phosphate (TNBP) and tris(isobutyl) phosphate (TIBP) in car dust. Tris(2-butoxyethyl) phosphate (TBOEP, median 22 ?g g(-1)) was dominant in house dust collected around and on electronics followed by tris(2-chloroisopropyl) phosphate (TCIPP, median 1.3 ?g g(-1)), tris(2-chloroethyl) phosphate (TCEP, median 1.3 ?g g(-1)) and tris(phenyl) phosphate (TPHP, median 0.8 ?g g(-1)). Levels of TPHP and tris(methylphenyl) phosphate (TMPP, also known as TCP) in house dust on electronics were significantly higher than in house dust collected around electronics, suggesting that electronic equipment has limited contribution to the PFR levels in house dust, with the exception of TPHP and TMPP. Car dust was dominated by tris(1,3-dichloroisopropyl) phosphate (TDCIPP) with the highest levels found in dust collected from the car seats (1100 ?g g(-1)). The mean TDCIPP and TCIPP levels observed in car dust were significantly higher than the levels observed in dust collected around electronics. Significantly higher mean TMPP levels in dust taken from car seats were found compared to dust collected around the equipment (p<0.05). This is probably influenced by the use of TDCIPP, TCIPP in polyurethane foam (car seats) and the use of TMPP as plasticizer in car interiors. Worldwide four PFR patterns were observed in house dust. The PFR pattern in the Netherlands of TDCIPP, TMPP, TCEP, TCIPP and TPHP in house dust is comparable to the pattern found in six other countries, which may point to identical sources of these PFRs in the indoor environment. However, the PFR levels between the countries and within countries showed high variation. PMID:24703013

  5. 77 FR 16796 - Lead Requirements for Lead-Based Paint Activities in Target Housing and Child-Occupied Facilities...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-22

    ...FRL-9649-6] Lead Requirements for Lead-Based Paint Activities in Target Housing and Child-Occupied...work practice standards for lead-based paint activities in target housing and child-occupied...establishing the Arkansas lead-based paint program and passed a new statute...

  6. A RANDOMIZED TRIAL OF THE EFFECT OF DUST CONTROL ON CHILDREN'S BLOOD LEAD LEVELS. ??? 627

    Microsoft Academic Search

    Bruce P. Lanphear; Nancy L. Winter; Leslie Apetz; Shirley Eberly; Michael Weitzman

    1996-01-01

    Objective. Dust control is recommended as one of the cornerstones of controlling childhood lead exposure; however, the effectiveness of dust control has not been demonstrated for children who have low to mild elevations in blood lead ( ie, less than 25 ? ?g\\/dL). The objective of this study was to determine whether dust control, as performed by families, had an

  7. Residual Oil Fly Ash Exposure Enhances Allergic Sensitization to House Dust Mite

    Microsoft Academic Search

    Amy L. Lambert; Wumin Dong; Darrell W. Winsett; MaryJane K. Selgrade; M. Ian Gilmour

    1999-01-01

    Epidemiological studies have shown an association between elevated levels of particulate matter air pollution and increased morbidity and hospital visits in asthmatics. Residual oil fly ash (ROFA) is a primary combustion particle containing sulfate and metals such as vanadium, nickel, and iron. In this study the effect of ROFA on sensitization to house dust mite (HDM) was examined in a

  8. Is the Atopy Patch Test with House Dust Mites Specific for Atopic Dermatitis?

    Microsoft Academic Search

    Vito Ingordo; Roberto Dalle Nogare; Bruno Colecchia; Corrado D’Andria

    2004-01-01

    Background: The atopy patch test (APT), namely the patch test with aeroallergens, is regarded as specific for patients with atopic dermatitis (AD), but small numbers of positive APT were reported in the past also in atopic subjects without dermatitis and in healthy persons. Objective: The aim of this study was to evaluate the response to the APT with house dust

  9. A combined transient hygrothermal and population model of House Dust Mites in beds

    Microsoft Academic Search

    S E C Pretlove; I Ridley; J A Horwood; B Leung; P Cox; D Thomson; N Baker; D Crowther

    This paper describes a current multi-disciplinary UK funded research project aimed at developing a hygrothermal model of house dust mite response to environmental conditions. The project involves the development of a transient hygrothermal bed model, which has been tested and validated by comparing its predictions with the environmental conditions measured in a bed in a test laboratory and in beds

  10. Double blind trial of ionisers in children with asthma sensitive to the house dust mite

    Microsoft Academic Search

    J A Warner; J L Marchant; J O Warner

    1993-01-01

    BACKGROUND--Manufacturers of ionisers claim many benefits from the use of their devices, including the relief of asthma. Particles removed from the air are likely to include airborne allergens, so ionisers may achieve an effect by reducing the allergen load. METHODS--The effect of ionisers on airborne concentrations of house dust mite allergen Der p I was investigated in a double blind,

  11. DIESEL AND CARBON PARTICLES ENHANCE HOUSE DUST MITE-INDUCED PULMONARY HYPERSENSITIVITY IN BROWN NORWAY RATS

    EPA Science Inventory

    Diesel and Carbon Particles Enhance House Dust Mite-Induced Pulmonary Hypersensitivity in Brown Norway Rats. P. Singh1, M.J. Daniels2, D. Winsett2, J. Richards2, K. Crissman2, M. Madden2 and M.I. Gilmour2. 1NCSU, Raleigh, NC and 2 USEPA, Research Triangle Park, NC. Ep...

  12. Comparison of Conjunctival and Nasal Provocation Test in Allergic Rhinitis to House Dust Mite

    Microsoft Academic Search

    Herbert Riechelmann; Barbara Epple; Gunther Gropper

    2003-01-01

    Background: Nasal allergen provocation tests (NPTs) are useful in confirming the diagnosis of allergic rhinitis, if data obtained by clinical history, skin tests and specific IgE determinations are not conclusive. Since NPTs are laborious, conjunctival provocation tests (CPTs) appear as an attractive alternative. The concordance of CPTs and NPTs with house dust mite allergen extract in sensitized and nonsensitized subjects

  13. In vitro T-lymphocyte response and house dust mite–induced bronchoconstriction

    Microsoft Academic Search

    Jung Hyun Chang; Henry Chan; Santiago Quirce; Tiffinie Green; Kukuh Noertjojo; Stephen Lam; Anthony Frew; Paul Keown; Moira Chan-Yeung

    1996-01-01

    Background: There is considerable evidence that T cells may play an important role in asthma. The purpose of this study was to determine whether the responsiveness of T lymphocytes to mite allergen stimulation in vitro is a determinant of bronchial response to house dust mite (HDM) allergen challenge in subjects who are allergic to HDM. Methods: Peripheral blood was taken

  14. Enhanced Allergic Responses to House Dust Mite by Oral Exposure to Carbaryl in Rats

    Microsoft Academic Search

    Wumin Dong; M. Ian Gilmour; Amy L. Lambert; MaryJane K. Selgrade

    1998-01-01

    Epidemiological studies have demonstrated an association between use of carbamate insecticides, including carbaryl, and increased incidence of allergic asthma in farmers. In this study the effect of oral carbaryl exposure on the development of allergic responses to house dust mite (HDM) was examined in female Brown Norway rats. Rats were gavaged for 2 weeks with 0, 2, 10, or 50

  15. House Dust Mite Allergen Characterisation: Implications for T-Cell Responses and Immunotherapy

    Microsoft Academic Search

    W. R. Thomas; W. Smith; B. J. Hales

    1998-01-01

    T cells are central regulators and mediators of allergic sensitisation and disease. The house dust mite allergens are a biochemically diverse group of proteins which are present in extracts and the environment in a wide range of concentrations. Here the importance of ascertaining the contribution of the different allergens to Th2 lymphokine production and the development of allergy is discussed

  16. House Dust Mite Der p 1 Downregulates Defenses of the Lung by Inactivating Elastase Inhibitors

    Microsoft Academic Search

    Alan Brown; Kinley Farmer; Louise MacDonald; Noor Kalsheker; Dave Pritchard; Chris Haslett; Jonathan Lamb; J.-M. Sallenave

    House dust mites (HDM) are the most common source of aero- allergens and in genetic susceptible individuals can cause symp- toms ranging from atopic dermatitis to bronchial asthma. Der p 1, a major target of the human immune responses to HDM, through its enzymatic properties can modulate the adaptive immune system by the cleavage of CD23 and CD25. The conse-

  17. Immune response to allergens in sheep sensitized to house dust mite

    Microsoft Academic Search

    Robert J Bischof; Ken J Snibson; Joanne Van Der Velden; Els NT Meeusen

    2008-01-01

    BACKGROUND: House dust mite (HDM) allergens are a major cause of allergic asthma. Most studies using animal models of allergic asthma have used rodents sensitized with the 'un-natural' allergen ovalbumin. It has only recently been recognized that the use of animal models based on HDM provide a more relevant insight into the allergen-induced mechanisms that underpin human allergic disease. We

  18. The relative allergenicity of Stachybotrys chartarum compared to house dust mite extracts in a mouse model

    EPA Science Inventory

    A report by the Institute of Medicine suggested that more research is needed to better understand mold effects on allergic disease, particularly asthma development. The authors compared the ability of the fungus Stachybotrys chartarum (SCE) and house dust mite (HDM) extracts to i...

  19. Exposure to house dust mite allergens and the clinical activity of asthma

    Microsoft Academic Search

    Adnan Custovic; Simon C. O. Taggart; Helen C. Francis; Martin D. Chapman; Ashley Woodcock

    1996-01-01

    Background: House dust mite allergens play an important role in inducing IgE-mediated sensitization and the development of bronchial hyperresponsiveness (BHR) and asthma. This study investigated the relationship between mite allergen exposure and the clinical activity and severity of asthma. Methods: Nonsmoking adult patients with asthma (n = 53) were randomly recruited from the asthma registry of two large family practitioner

  20. ANALYSIS OF SOIL AND HOUSE DUST FOR POLYCYCLIC AROMATIC HYDROCARBONS

    EPA Science Inventory

    It has been conjectured that jet turbine exhaust near airplane flight paths may result in significant human exposure to PAH. The fallout from the aerosol plume could be introduced into the residence directly as drafts through the interior of the house or through accumulation of ...

  1. Pathways of Lead Exposure in Urban Children

    Microsoft Academic Search

    Bruce P. Lanphear; Klaus J. Roghmann

    1997-01-01

    A linear structural equation modeling procedure was used to explore the mechanisms and pathways for lead intake among urban children and the relative contribution of various lead sources to lead-contaminated house dust. Dust lead levels were significantly associated with children's blood lead levels, both indirectly and directly via hand lead. Both soil and paint lead contributed to dust lead levels,

  2. Testing Your Home for Lead in Paint, Dust, and Soil

    MedlinePLUS

    ... practices, Specific Questions About Testing Paint, Dust, And Soil Section 2 Q: Q: A: A: 8 XRF ... dust testing. Q: A: Q: A: How Are Soil Samples Collected And Analyzed? Soil samples are collected ...

  3. Urinary Metabolites of Organophosphate Flame Retardants: Temporal Variability and Correlations with House Dust Concentrations

    PubMed Central

    Cooper, Ellen M.; Stapleton, Heather M.; Hauser, Russ

    2013-01-01

    Background: A reduction in the use of polybrominated diphenyl ethers (PBDEs) because of human health concerns may result in an increased use of and human exposure to organophosphate flame retardants (OPFRs). Human exposure and health studies of OPFRs are lacking. Objectives: We sought to define the degree of temporal variability in urinary OPFR metabolites in order to inform epidemiologic study design, and to explore a potential primary source of exposure by examining the relationship between OPFRs in house dust and their metabolites in urine. Methods: Nine repeated urine samples were collected from 7 men over the course of 3 months and analyzed for bis(1,3-dichloro-2-propyl) phosphate (BDCPP) and diphenyl phosphate (DPP), metabolites of the OPFRs tris(1,3-dichloro-2-propyl) phosphate (TDCPP) and triphenyl phosphate (TPP), respectively. Intraclass correlation coefficients (ICCs) were calculated to characterize temporal reliability. Paired house dust and urine samples were collected from 45 men. Results: BDCPP was detected in 91% of urine samples, and DPP in 96%. Urinary BDCPP showed moderate-to-strong temporal reliability (ICC range, 0.55–0.72). ICCs for DPP were lower, but moderately reliable (range, 0.35–0.51). There was a weak [Spearman r (rS) = 0.31] but significant (p = 0.03) correlation between urinary BDCPP and TDCPP concentrations in house dust that strengthened when nondetects (rS = 0.47) were excluded. There was no correlation between uncorrected DPP and TPP measured in house dust (rS < 0.1). Conclusions: Household dust may be an important source of exposure to TDCPP but not TPP. Urinary concentrations of BDCPP and DPP were moderately to highly reliable within individuals over 3 months. PMID:23461877

  4. Allergic and nonallergic interactions between house dust mite allergens and airway mucosa.

    PubMed

    Roche, N; Chinet, T C; Huchon, G J

    1997-03-01

    Asthma and allergy are extremely frequent diseases, affecting 5-10% and 30% of the population, respectively. The prevalence of asthma has increased in many developed countries, which may be due to several factors, including increased exposure to house dust mite (HDM) allergens. HDM to which humans are most frequently sensitized are Dermatophagoides pteronyssinus, Dermatophagoides farinae, and Euroglyphus maynei. These mites multiply in carpets, bedding and upholstered furniture in a hot and humid atmosphere. The allergens are digestive enzymes of the mites. Several epidemiological studies have shown that an increase in exposure to HDMs is associated with an increase in the prevalence of sensitization and asthma, whereas mite avoidance leads to a decrease in respiratory symptoms of sensitized asthmatic subjects. Sensitized subjects have specific immunoglobulin G and E (IgG and IgE) humoral responses, as well as proliferative T-cell responses to HDM allergens. Experimental exposure to HDM allergens induces bronchoalveolar inflammatory responses, that are characterized by the recruitment and activation of eosinophils, mastocytes, neutrophils, monocytes and lymphocytes. The cysteine protease activity of Der p 1 (a major allergen of D. pteronyssinus) has been shown to increase airway mucosal permeability, and may thereby contribute to the pathogenesis of airway inflammation and hyperresponsiveness by nonimmunological mechanisms. These epidemiological and experimental data support the recommendations for mite avoidance, especially in persons at high risk of developing asthma. PMID:9073012

  5. The Innate Immune Response in House Dust Mite-Induced Allergic Inflammation

    PubMed Central

    2013-01-01

    Hypersensitivity to house dust mite (HDM; Dermatophagoides sp.) allergens is one of the most common allergic responses, affecting up to 85% of asthmatics. Sensitization to indoor allergens is the strongest independent risk factor associated with asthma. Additionally, >50% of children and adolescents with asthma are sensitized to HDM. Although allergen-specific CD4+ Th2 cells orchestrate the HDM allergic response through induction of IgE directed toward mite allergens, activation of innate immunity also plays a critical role in HDM-induced allergic inflammation. This review highlights the HDM components that lead to activation of the innate immune response. Activation may due to HDM proteases. Proteases may be recognized by protease-activation receptors (PARs), Toll-like receptors (TLRs), or C-type lectin receptors (CTRs), or act as a molecular mimic for PAMP activation signaling pathways. Understanding the role of mite allergen-induced innate immunity will facilitate the development of therapeutic strategies that exploit innate immunity receptors and associated signaling pathways for the treatment of allergic asthma. PMID:23450108

  6. Pyrethroids in house dust from the homes of farm worker families in the MICASA study

    PubMed Central

    Trunnelle, Kelly J.; Bennett, Deborah H.; Tancredi, Daniel J.; Gee, Shirley J.; Stoecklin-Marois, Maria T.; Hennessy-Burt, Tamara E.; Hammock, Bruce D.; Schenker, Marc B.

    2014-01-01

    Indoor pesticide exposure is a growing concern, particularly for pyrethroids, a commonly used class of pesticides. Pyrethroid concentrations may be especially high in homes of immigrant farm worker families, who often live in close proximity to agricultural fields and are faced with poor housing conditions, potentially causing high pest infestation and pesticide use. We investigate levels of pyrethroids in the house dust of farm worker family homes in a study of mothers and children living in Mendota, CA, within the population-based Mexican Immigration to California: Agricultural Safety and Acculturation (MICASA) Study. We present pesticide use data and levels of pyrethroid pesticides in indoor dust collected in 2009 as measured by questionnaires and a GC/MS analysis of the pyrethroids cis- and trans-permethrin, cypermethrin, deltamethrin, esfenvalerate and resmethrin in single dust samples collected from 55 households. Cis- and trans-permethrin had the highest detection frequencies at 67%, with median concentrations of 244 and 172 ng/g dust, respectively. Cypermethrin was detected in 52% of the homes and had a median concentration of 186 ng/g dust. Esfenvalerate, resmethrin and deltamethrin were detected in less than half the samples. We compared the pyrethroid concentrations found in our study to other studies looking at both rural and urban homes and daycares. Lower detection frequencies and/or lower median concentrations of cis- and trans-permethrin and cypermethrin were observed in our study as compared to those studies. However, deltamethrin, esfenvalerate and resmethrin were detected more frequently in the house dust from our study than in the other studies. Because households whose children had higher urinary pyrethroid metabolite levels were more likely to be analyzed in this study, a positive bias in our estimates of household pyrethroid levels may be expected. A positive association was observed with reported outdoor pesticide use and cypermethrin levels found in the indoor dust samples (rs = 0.28, p = 0.0450). There was also a positive association seen with summed pyrethroid levels in house dust and the results of a pesticide inventory conducted by field staff (rs = 0.32, p = 0.018), a potentially useful predictor of pesticide exposure in farm worker family homes. Further research is warranted to fully investigate the utility of such a measure. PMID:24096042

  7. Distribution of pesticides and polycyclic aromatic hydrocarbons in house dust as a function of particle size.

    PubMed Central

    Lewis, R G; Fortune, C R; Willis, R D; Camann, D E; Antley, J T

    1999-01-01

    House dust is a repository for environmental pollutants that may accumulate indoors from both internal and external sources over long periods of time. Dust and tracked-in soil accumulate most efficiently in carpets, and the pollutants associated with dust and soil may present an exposure risk to infants and toddlers, who spend significant portions of their time in contact with or in close proximity to the floor and who engage in frequent mouthing activities. The availability of carpet dust for exposure by transfer to the skin or by suspension into the air depends on particle size. In this study, a large sample of residential house dust was obtained from a commercial cleaning service whose clients were homeowners residing in the Raleigh-Durham-Chapel Hill (Research Triangle) area of North Carolina. The composite dust was separated into seven size fractions ranging from < 4 to 500 microm in diameter, and each fraction was analyzed for 28 pesticides and 10 polycyclic aromatic hydrocarbons (PAHs). Over 20% of the fractionated dust sample consisted of particles < 25 microm in diameter. Fourteen pesticides and all 10 of the target PAHs were detected in one or more of the seven size-fractionated samples. Sample concentrations reported range from 0.02 to 22 microg/g; the synthetic pyrethroids cis- and trans-permethrin were the most abundant pesticide residue. The concentrations of nearly all of the target analytes increased gradually with decreasing particle size for the larger particles, then increased dramatically for the two smallest particle sizes (4-25 microm and < 4 microm). Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:10464072

  8. Detection of Organophosphate Flame Retardants in Furniture Foam and US House Dust

    PubMed Central

    Stapleton, Heather M.; Klosterhaus, Susan; Eagle, Sarah; Fuh, Jennifer; Meeker, John D.; Blum, Arlene; Webster, Thomas F.

    2009-01-01

    Restrictions on the use of polybrominated diphenyl ethers (PBDEs) have resulted in the increased use of alternate flame retardant chemicals to meet flammability standards. However, it has been difficult to determine which chemical formulations are currently being used in high volumes to meet flammability standards since the use of flame retardant formulations in consumer products is not transparent (i.e. not provided to customers). To investigate chemicals being used as replacements for PentaBDE in polyurethane foam, we analyzed foam samples from 26 different pieces of furniture purchased in the United States primarily between 2003 and 2009 using gas chromatography mass spectrometry. Samples included foam from couches, chairs, mattress pads, pillows, and, in one case, foam from a sound proofing system of a laboratory grade dust sieve. Fifteen of the foam samples contained the flame retardant tris(1,3-dichloro-2-propyl) phosphate (TDCPP; 1–5% by weight), four samples contained tris(1-chloro-2-propyl) phosphate (TCPP; 0.5 –2.2 % by weight), one sample contained brominated chemicals found in a new flame retardant mixture called Firemaster 550 (4.2% by weight), and one foam sample collected from a futon likely purchased prior to 2004 contained PentaBDE (0.5% by weight). Due to the high frequency of detection of the chlorinated phosphate compounds in furniture foam, we analyzed extracts from 50 house dust samples collected between 2002 and 2007 in the Boston, MA area for TDCPP, TCPP, and another high volume use organophosphate-based flame retardant used in foam, triphenylphosphate (TPP). Detection frequencies for TDCPP and TPP in the dust samples were >96% and were log normally distributed, similar to observations for PBDEs. TCPP was positively detected in dust in only 24% of the samples, but detection was significantly limited by a co-elution problem. The geometric mean concentrations for TCPP, TDCPP and TPP in house dust were 570, 1890, and 7360 ng/g, respectively, and maximum values detected in dust were 5490, 56,080 and 1,798,000 ng/g, respectively. These data suggest that levels of these organophosphate flame retardants are comparable, or in some cases, greater than, levels of PBDEs in house dust. The high prevalence of these chemicals in foam and the high concentrations measured in dust (as high as 1.8 mg/g), warrant further studies to evaluate potential health effects from dust exposure, particularly for children. PMID:19848166

  9. Condition and type of housing as an indicator of potential environmental lead exposure and pediatric blood lead levels

    Microsoft Academic Search

    C. S. Clark; R. L. Bornschein; P. Succop; S. S. Que Hee; P. B. Hammond; B. Peace

    1985-01-01

    Environmental evaluations in a prospective behavior study of children with blood lead levels up to about 50 g\\/dl were performed by an intensive environmental survey and by exterior visual evaluations of housing quality. Serial blood lead values for infants in the study were compared to exterior housing type and quality, which itself was also compared with results of the intensive

  10. Generation of a transgenic rice seed-based edible vaccine against house dust mite allergy

    Microsoft Academic Search

    Lijun Yang; Hiroyuki Kajiura; Kazuya Suzuki; Sakiko Hirose; Kazuhito Fujiyama; Fumio Takaiwa

    2008-01-01

    As an alternative approach to conventional allergen-specific immunotherapy, transgenic rice seed expressing a major house dust mite (HDM) allergen, Der p 1, was developed as an edible vaccine. The C-terminal KDEL-tagged Der p 1 allergen specifically accumulated in seed endosperm tissue under the control of the endosperm-specific GluB1 promoter. Der p 1 reached a maximum concentration of 58?g\\/grain and was

  11. Impact of Sublingual Immunotherapy on Specific Antibody Levels in Asthmatic Children Allergic to House Dust Mites

    Microsoft Academic Search

    Nerin N. Bahceciler; Cigdem Arikan; Alison Taylor; Mubeccel Akdis; Kurt Blaser; Isil B. Barlan; Cezmi A. Akdis

    2005-01-01

    Objective: To evaluate the clinical outcome and changes in allergen-specific antibodies during sublingual immunotherapy (SLIT) in house dust mite (HDM)-allergic asthma patients and to compare levels of allergen-specific antibodies in HDM-allergic patients before and after treatment with that of healthy controls. Method: Thirty-one asthma patients allergic to HDM were studied. Patients in groups I (n = 17) and II (n

  12. Murine Allergic Respiratory Responses to the Major House Dust Mite Allergen Der p 1

    Microsoft Academic Search

    Amanda H. Clarke; Wayne R. Thomas; Jennifer M. Rolland; Christopher Dow; Richard M. O’Brien

    1999-01-01

    Background: Although many studies have examined chronic asthma, limited data exist on acute immunopathogenic events induced by allergens. The aim of the study was to investigate the acute cellular, serologic and histopathologic events in airway inflammation produced by intranasal challenge of mice sensitised to the major house dust mite allergen Der p 1. Methods: C57BL/6 mice were immunised subcutaneously with

  13. Clonal Analysis of Human T-Cell Responses to Fractionated House Dust Mite Antigens (Dermatophagoides pteronyssinus)

    Microsoft Academic Search

    Mitsuhiro Okano; Toshiaki Nagano; Toshiro Ono; Yu Masuda; Nobuo Ohta

    1993-01-01

    In the present study, we investigated the cellular basis of house dust mite-driven immune responsiveness in an atopic individual with perennial rhinitis. We established 40 human T-cell clones (CD3+, 4+, 8––) reactive to Dermatophagoides pteronyssinus (Dp) antigen under the restriction of HLA-DR. By using the crude Dp antigen and its 14 molecular weight (MW) fractions, we analyzed the distribution of

  14. House-dust Mite Asthma. Results of Challenge Tests on Five Criteria with Dermatophagoides pteronyssinus

    Microsoft Academic Search

    Monica K. McAllen; E. S. K. Assem; K. Maunsell

    1970-01-01

    Twenty-eight patients with asthma and house-dust allergy were investigated by five different challenge tests with mite extract (Dermatophagoides pteronyssinus). These tests were performed on the skin, bronchi, nasal mucosa, and leucocytes, and on normal human lung tissue passively sensitized by the patients' serum. The results were compared with each other and with the clinical state of the patients.Of 21 patients

  15. Clonal Analysis of the Cellular Immune Response to the House Dust Mite Dermatophagoides farinae

    Microsoft Academic Search

    Robyn O’Hehir; Douglas Young; Barry Kay; Jonathan Lamb

    1989-01-01

    A panel of human CD4+ T cell clones specific for the house dust mite was isolated from an atopic individual with perennial rhinitis. Soluble antigen specificity was defined using proliferation assays and subsequently the antigenic determinants recognized by some of these clones were mapped using nitrocellulose immunoblots of fractionated Dermatophagoides spp. Both cross-reactive and species-specific T cell clones were identified

  16. Serum Reagins and Leucocyte Response in Patients with House-dust Mite Allergy

    Microsoft Academic Search

    E. S. K. Assem; Monica K. McAllen

    1970-01-01

    A study was carried out on 26 patients with respiratory allergy due to the house-dust mite Dermatophagoides pteronyssinus and on 10 non-allergic control subjects using two in-vitro histamine release tests for assessing immediate-type allergy. The first test was on the patients' serum and assessed reaginic (anaphylactic; possibly IgE) antibodies by passive sensitization of normal human lung tissue. The second test

  17. Induction of Allergic Reactions in Guinea Pigs with Purified House Dust Mite Allergens

    Microsoft Academic Search

    Masaaki Yasue; Toyokazu Yokota; Hirokazu Okudaira; Yasushi Okumura

    1999-01-01

    To establish a guinea pig model for house dust mite allergy with purified mite allergens, we studied the immune response to two major mite allergens, native Der f 1 (nDer f 1) and recombinant Der f 2 (rDer f 2) and crude mite extract in Hartley guinea pigs. Animals were immunized with either mite extract, nDer f 1 or rDer

  18. Paradoxical Effects of Rapamycin on Experimental House Dust Mite-Induced Asthma

    Microsoft Academic Search

    Karin Fredriksson; Jill A. Fielhaber; Jonathan K. Lam; Xianglan Yao; Katharine S. Meyer; Karen J. Keeran; Gayle J. Zywicke; Xuan Qu; Zu-Xi Yu; Joel Moss; Arnold S. Kristof; Stewart J. Levine

    2012-01-01

    The mammalian target of rapamycin (mTOR) modulates immune responses and cellular proliferation. The objective of this study was to assess whether inhibition of mTOR with rapamycin modifies disease severity in two experimental murine models of house dust mite (HDM)-induced asthma. In an induction model, rapamycin was administered to BALB\\/c mice coincident with nasal HDM challenges for 3 weeks. In a

  19. The Role of the House Dust Mite-Induced Innate Immunity in Development of Allergic Response

    Microsoft Academic Search

    Alain Jacquet

    2011-01-01

    House dust mite (HDM) represents one of the most common sources of aeroallergens worldwide and more than 50% of allergic patients are sensitized to these allergenic molecules. HDM allergy research in the past has been mainly focused on adaptive, mite allergen-dependent immune responses. In recent years it has become clear that, although the allergen-specific CD4+ Th2 cellsorchestrate HDM allergic response,the

  20. Organic contamination of settled house dust, a review for exposure assessment purposes.

    PubMed

    Mercier, Fabien; Glorennec, Philippe; Thomas, Olivier; Le Bot, Barbara

    2011-08-15

    People spend a considerable amount of time indoors. As a result, exposure to indoor contaminants is of great concern, notably via settled dust ingestion in particular for infants and toddlers. This paper proposes a critical review on the organic contamination of settled house dust and human exposure over the past 10 years and focused on sources, contaminations and measurement methods (sampling, pretreatment, storage and analysis). As many compounds were identified, arises the question of which ones to consider. Sensitive and selective analytical methods for simultaneous determination of targeted substances should be developed and evaluated. Various methods were described for sampling and sample preparation. Harmonization and standardization are needed to enable comparison of results from similar studies. Finally, an integrated multipollutant and multicompartment (settled dust, suspended particles and air) approach appears essential in order to determine the extent of the threat to public health posed by indoor contaminants. PMID:21667945

  1. An ecological survey of lead contents in roadside dusts and soils in Hong Kong

    Microsoft Academic Search

    W. M. Lau; H. M. Wong

    1982-01-01

    Samples of roadside dusts and soils were collected at 14 selected sites in Hong Kong. Lead and other metals in these samples were found to have significant correlation with the annual average daily traffic (AADT) (r = 0.93, P < 0.005). Lead in the dust samples (1627 ppm) is much higher than its content in normal soil (15 ppm). Examination

  2. Evaluation of possible arrestant-aggregation pheromones in the American house dust mite, Dermatophagoides farinae Hughes (astigmata: Pyroglyphidae)

    Microsoft Academic Search

    Emmett V. Glass; Jay A. Yoder; Glen R. Needham

    2001-01-01

    We wanted to determine if a chemical substance was responsible for cluster formation by adults of the American house dust mite, Dermatophagoides farinae Hughes, which are significant agents of dust allergy in humans. Behavioral responses to an extract of aggregated mites were compared to 30 common mite attractants identified in cuticular lipids, excretory products and mammalian skin in a refined

  3. Electrostatic charge characteristics of Der p1 allergen-carrying particles and the house dust mite dermatophagoides pteronyssinus.

    PubMed

    Gaynor, P T; Hughes, J F

    1998-05-01

    Control of the house dust mite allergen has received considerable attention owing to its importance in some allergic diseases. One aspect of dust mites and their allergen-carrying faecal particles that has not been reported on, which may have allergen control applications, is the electrostatic charge they carry in the natural environment. To promote tribo-electric charging, household dust containing dust mite allergen and live house dust mites are separately agitated while in contact with either polypropylene, nylon or earthed metal. The charged dust and mites are subsequently subjected to electrostatic separation and collection. Results for concentrations of the house dust mite allergen, Der p1, indicate that, when subjected to nylon, Der p1 carrier particles appear to be predominantly positively charged. Similarly, when subjected to polypropylene, Der p1 carrier particles also appear to be positively charged. Reduction of excess free charge by agitation against earthed metal does not appear to affect the observed charging characteristics, indicating that the positive charge may be bound or inherent in the Der p1 carrier particles. In contrast, house dust mites exposed to nylon appear to be generally charging negative, whereas mites exposed to polypropylene appear to be charging positive. The observed electrostatic characteristics of the mites and Der p1 carrying particles will be useful in the future development of electrostatic allergen control methods. PMID:9747576

  4. New house dust collection system and its use in a study of asthma in dust mite sensitive children in Raleigh, North Carolina

    SciTech Connect

    Lindstrom, A.B.; Beck, M.A.; Henry, M.M.; Barnes, D.M.; Henderson, F.W.

    1993-01-01

    A prototype dust collection system, the House Dust Vacuum One (HDVI), was designed for use in a study to investigate the relationship between house dust mite antigen levels and the presence of asthma in dust mite sensitive children. The HDVI was designed for the collection of dust samples from all potentially relevant domestic substrates, with the primary sampling objective being the retrieval at least 100 mg of sample material. During the winter of 1991-92, dust samples were collected from six different microenvironments in the homes of 49 dust mite sensitive children living in the Raleigh, NC metropolitan area. In addition to the standard antigen immunoassay, the performance of the HDVI was assessed by conducting side by side comparison tests using two alternative antigen collection systems. Microenvironmental antigen concentrations were found to be lognormally distributed within the test homes and within each microenvironment. With the relatively large quantity of sample material collected and the ease with which the HDVI was able to collect samples from a wide variety of substrates, the new unit was determined to be well suited for surface dust and dust mite antigen collection studies.

  5. Serum PBDEs in a North Carolina Toddler Cohort: Associations with Handwipes, House Dust, and Socioeconomic Variables

    PubMed Central

    Eagle, Sarah; Sjödin, Andreas; Webster, Thomas F.

    2012-01-01

    Background: Polybrominated diphenyl ethers (PBDEs) are persistent, bioaccumulative, and endocrine-disrupting chemicals. Objectives: We used handwipes to estimate exposure to PBDEs in house dust among toddlers and examined sex, age, breast-feeding, race, and parents’ education as predictors of serum PBDEs. Methods: Eighty-three children from 12 to 36 months of age were enrolled in North Carolina between May 2009 and November 2010. Blood, handwipe, and house dust samples were collected and analyzed for PBDEs. A questionnaire was administered to collect demographic data. Results: PBDEs were detected in all serum samples (geometric mean for ?pentaBDE in serum was 43.3 ng/g lipid), 98% of the handwipe samples, and 100% of the dust samples. Serum ?pentaBDEs were significantly correlated with both handwipe and house dust ?pentaBDE levels, but were more strongly associated with handwipe levels (r = 0.57; p < 0.001 vs. r = 0.35; p < 0.01). Multivariate model estimates revealed that handwipe levels, child’s sex, child’s age, and father’s education accounted for 39% of the variation in serum ?BDE3 levels (sum of BDEs 47, 99, and 100). In contrast, age, handwipe levels, and breast-feeding duration explained 39% of the variation in serum BDE 153. Conclusions: Our study suggests that hand-to-mouth activity may be a significant source of exposure to PBDEs. Furthermore, age, socioeconomic status, and breast-feeding were significant predictors of exposure, but associations varied by congener. Specifically, serum ?BDE3 was inversely associated with socioeconomic status, whereas serum BDE-153 was positively associated with duration of breast-feeding and mother’s education. PMID:22763040

  6. Characterization of lead, chromium, and cadmium in dust emitted from municipal solid waste incineration plants

    NASA Astrophysics Data System (ADS)

    Shiota, K.; Imai, G.; Oshita, K.; Takaoka, M.

    2013-04-01

    The dust is emitted from municipal solid waste incinerators (MSWIs). Volatile toxic heavy metals are abundant in smaller dust particles and influence the toxicity of particulate matter such as fine particles <2.5 ?m (PM2.5). However, little is known about the properties of these metals in fine dust particles. Therefore, X-ray absorption fine structure (XAFS) spectroscopy was used to investigate the chemical states of lead (Pb), chromium (Cr), and cadmium (Cd) in MSWI dust collected for nine particle size fractions at the inlet of the dust collector and the stacks of two MSWI plants. XAFS spectroscopy of the dust in the inlet of the dust collectors showed that finer dust contained predominantly Pb as PbCl2 with some PbSiO3, coarser dust consisted of Cr forms, including more toxic Cr(VI) species, and all dust contained CdCl2. Although the dust collector removed almost all of the Pb, trace amounts of PbCl2 remained in the stack gas after passing through the dust collector.

  7. Detection and intake assessment of organophosphate flame retardants in house dust in Japanese dwellings.

    PubMed

    Tajima, Shuji; Araki, Atsuko; Kawai, Toshio; Tsuboi, Tazuru; Ait Bamai, Yu; Yoshioka, Eiji; Kanazawa, Ayako; Cong, Shi; Kishi, Reiko

    2014-04-15

    The demand for phosphorus flame retardants (PFRs) has recently increased as an alternative to polybrominated diphenyl ether (PBDE). PFRs have been detected in house dust, but little is known about the concentrations of PFRs in private homes and the effects on human health. We measured the levels of 10 PFRs in indoor floor dust and upper surface dust from 128 Japanese dwellings of families with children in elementary school. The median (min-max) concentrations (?g/g) of PFRs were as follows: tris(2-butoxyethyl) phosphate (TBOEP), 30.88 (<0.61-936.65); tris(2-chloro-iso-propyl) phosphate (TCIPP), 0.74 (<0.56-392.52); and triphenyl phosphate (TPHP), 0.87 (<0.80-23.35). These values exceeded 50% detection rates, and the rates are median over the LOD in floor dust. The concentrations (?g/g) of TBOEP 26.55 (<0.61-1933.24), TCIPP 2.23 (<0.56-621.23), TPHP 3.13 (<0.80-27.47), tris(2-chloroethyl) phosphate (TCEP) 1.17 (<0.65-92.22), and tributyl phosphate (TNBP) 0.74 (<0.36-60.64) exceeded 50% detection rates in the upper surface dust. A significant positive correlation (P<0.05) between the concentrations of TCIPP and TBOEP was shown in floor dust and upper surface dust (n=48). Estimated median and 95th percentile daily intake was calculated for toddlers and elementary school children and was compared with reference dose values (RfD) from the literature. For TBOEP, the estimated 95th percentile intake from floor dust was 14% of RfD for toddlers and 4% for school children. The estimated intake from upper surface dust was somewhat lower. Estimated median intake of TBOEP and median intake for the other PFRs were less than 1% of the RfD. TBOEP, TCIPP and TPHP were the main PFRs in the dust. The median levels of PFRs are well below the RfD values. PMID:24531310

  8. Levels of phthalate esters in settled house dust from urban dwellings with young children in Nanjing, China

    NASA Astrophysics Data System (ADS)

    Zhang, Qi; Lu, Xiao-Mei; Zhang, Xiao-Ling; Sun, Yong-Gang; Zhu, Dong-Mei; Wang, Bing-Ling; Zhao, Ren-Zheng; Zhang, Zheng-Dong

    2013-04-01

    To investigate the levels and possible determinants of phthalate esters (PEs) in settled house dust from urban dwellings with young children, dust was collected from 215 urban houses in Nanjing, China, and 145 outdoor settled dust samples were collected nearby. Six PEs were measured by gas chromatography/mass spectrometry. All PEs were detected in the dust from approximately 90% of the houses, with the exception of dioctyl phthalate (DOP), which had only a 59% detection rate. Di-2-ethylhexyl phthalate (DEHP) and di-n-butyl phthalate (DBP) were the most abundant PEs, with geometric means of 110 and 16.4 ?g g-1, respectively, and maximal concentrations 9950 and 2150 ?g g-1. Factor analysis showed that DBP, DEHP and benzyl butyl phthalate (BBP) might come from the same source and were significantly influenced by the use of solid-wood floor wax. High BBP, DEHP, DOP and total PE levels were associated with indices of dampness, and high DOP was associated with humidifier use. In conclusion, six PEs are ubiquitous in urban settled house dust in Nanjing, China, and both plastic materials and cosmetic and personal care products are important sources. Flooring material, dampness and humidifier use potentially influence house dust PE levels.

  9. Acarosan and the Acarex test in the control of house dust mite allergens in the home.

    PubMed

    Ridout, S; Twiselton, R; Matthews, S; Stevens, M; Matthews, L; Arshad, S H; Hide, D W

    1993-01-01

    House dust mites are believed to be major triggers for allergic disease in atopic individuals. As part of a programme controlling dietary and aero-allergen exposure in high-risk infants, an acaricidal foam and powder (Acarosan) was applied to bedroom and main living room carpets, as well as upholstered furniture, on four occasions in the first year of life. Dust was assayed for mite antigen (Der p1) and these results compared with the semi-quantitative assay of guanine content (Acarex Test). After nine months mean Der p1 levels had decreased by 70% in the treatment group. Proportionally, the greatest fall occurred in those items that had the highest initial mite antigen content. The Acarex score does show a correlation with Der p1 levels, but cannot replace antigen assay when accurate data is required. A chemical acaricide may help reduce house dust mite antigen levels, but is not by itself sufficient to reduce levels below that considered critical for sensitisation. PMID:8347439

  10. Effects of physical interventions on house dust mite allergen levels in carpet, bed, and upholstery dust in low-income, urban homes.

    PubMed

    Vojta, P J; Randels, S P; Stout, J; Muilenberg, M; Burge, H A; Lynn, H; Mitchell, H; O'Connor, G T; Zeldin, D C

    2001-08-01

    House dust mite allergen exposure is a postulated risk factor for allergic sensitization, asthma development, and asthma morbidity; however, practical and effective methods to mitigate these allergens from low-income, urban home environments remain elusive. The purpose of this study was to assess the feasibility and effectiveness of physical interventions to mitigate house dust mite allergens in this setting. Homes with high levels of house dust mite allergen (Der f 1 + Der p 1 > or = 10 microg/g dust by enzyme-linked immunosorbent assay) in the bed, bedroom carpet, and/or upholstered furniture were enrolled in the study. Carpets and upholstered furniture were subjected to a single treatment of either dry steam cleaning plus vacuuming (carpet only) or intensive vacuuming alone. Bed interventions consisted of complete encasement of the mattress, box spring, and pillows plus either weekly professional or in-home laundering of nonencased bedding. Dust samples were collected at baseline and again at 3 days (carpet and upholstery only) and 2, 4, and 8 weeks posttreatment. We compared pretreatment mean allergen concentrations and loads to posttreatment values and performed between-group analyses after adjusting for differences in the pretreatment means. Both dry steam cleaning plus vacuuming and vacuuming alone resulted in a significant reduction in carpet house dust mite allergen concentration and load (p < 0.05). Levels approached pretreatment values by 4 weeks posttreatment in the intensive vacuuming group, whereas steam cleaning plus vacuuming effected a decrease that persisted for up to 8 weeks. Significant decreases in bed house dust mite allergen concentration and load were obtained in response to encasement and either professional or in-home laundering (p < 0.001). Between-group analysis revealed significantly less postintervention house dust mite allergen load in professionally laundered compared to home-laundered beds (p < 0.05). Intensive vacuuming and dry steam cleaning both caused a significant reduction in allergen concentration and load in upholstered furniture samples (p < 0.005). Based on these data, we conclude that physical interventions offer practical, effective means of reducing house dust mite allergen levels in low-income, urban home environments. PMID:11564617

  11. Monitoring Indoor Exposure to Organophosphate Flame Retardants: Hand Wipes and House Dust

    PubMed Central

    Hoffman, Kate; Garantziotis, Stavros; Birnbaum, Linda S.

    2014-01-01

    Background: Organophosphate flame retardants (PFRs) are becoming popular replacements for the phased-out polybrominated diphenyl ether (PBDE) mixtures, and they are now commonly detected in indoor environments. However, little is known about human exposure to PFRs because they cannot be easily measured in blood or serum. Objectives: To investigate relationships between the home environment and internal exposure, we assessed associations between two PFRs, tris(1,3-dichloropropyl) phosphate (TDCIPP) and triphenyl phosphate (TPHP), in paired hand wipe and dust samples and concentrations of their metabolites in urine samples (n = 53). We also assessed short-term variation in urinary metabolite concentrations (n = 11 participants; n = 49 samples). Methods: Adult volunteers in North Carolina, USA, completed questionnaires and provided urine, hand wipe, and household dust samples. PFRs and PBDEs were measured in hand wipes and dust, and bis(1,3-dichloropropyl) phosphate (BDCIPP) and diphenyl phosphate (DPHP), metabolites of TDCIPP and TPHP, were measured in urine. Results: TDCIPP and TPHP were detected frequently in hand wipes and dust (> 86.8%), with geometric mean concentrations exceeding those of PBDEs. Unlike PBDEs, dust TDCIPP and TPHP levels were not associated with hand wipes. However, hand wipe levels were associated with urinary metabolites. Participants with the highest hand wipe TPHP mass, for instance, had DPHP levels 2.42 times those of participants with the lowest levels (95% CI: 1.23, 4.77). Women had higher levels of DPHP, but not BDCIPP. BDCIPP and DPHP concentrations were moderately to strongly reliable over 5 consecutive days (intraclass correlation coefficients of 0.81 and 0.51, respectively). Conclusions: PFR exposures are widespread, and hand-to-mouth contact or dermal absorption may be important pathways of exposure. Citation: Hoffman K, Garantziotis S, Birnbaum LS, Stapleton HM. 2015. Monitoring indoor exposure to organophosphate flame retardants: hand wipes and house dust. Environ Health Perspect 123:160–165;?http://dx.doi.org/10.1289/ehp.1408669 PMID:25343780

  12. COST ESTIMATES OF USING THREE LEAD-BASED PAINT ABATEMENT TECHNOLOGIES ON RESIDENTIAL HOUSING

    EPA Science Inventory

    Elevated blood lead levels in children of the US due to exposure to flaking lead-based paint continues to be an important health concern. Approximately 57M housing units, which represent 75% of all privately owned and occupied housing built before 1980 in the US are contaminated ...

  13. Coal-tar-based parking lot sealcoat: An unrecognized source of PAH to settled house dust

    USGS Publications Warehouse

    Mahler, B.J.; Van Metre, P.C.; Wilson, J.T.; Musgrove, M.; Burbank, T.L.; Ennis, T.E.; Bashara, T.J.

    2010-01-01

    Despite much speculation, the principal factors controlling concentrations of polycyclic aromatic hydrocarbons (PAH) in settled house dust (SHD) have not yet been identified. In response to recent reports that dust from pavement with coaltar-based sealcoat contains extremely high concentrations of PAH, we measured PAH in SHD from 23 apartments and in dust from their associated parking lots, one-half of which had coal-tar-based sealcoat (CT). The median concentration of total PAH (T-PAH) in dust from CT parking lots (4760 ??g/g, n = 11) was 530 times higher than that from parking lots with other pavement surface types (asphalt-based sealcoat, unsealed asphalt, concrete [median 9.0 ??g/g, n = 12]). T-PAH in SHD from apartments with CT parking lots (median 129 ??g/g) was 25 times higher than that in SHD from apartments with parking lots with other pavement surface types (median 5.1 ??g/g). Presence or absence of CT on a parking lot explained 48% of the variance in log-transformed T-PAH in SHD. Urban land-use intensity near the residence also had a significant but weaker relation to T-PAH. No other variables tested, including carpeting, frequency of vacuuming, and indoor burning, were significant. ?? 2010 American Chemical Society.

  14. Coal-tar-based parking lot sealcoat: an unrecognized source of PAH to settled house dust.

    PubMed

    Mahler, Barbara J; Metre, Peter C Van; Wilson, Jennifer T; Musgrove, Marylynn; Burbank, Teresa L; Ennis, Thomas E; Bashara, Thomas J

    2010-02-01

    Despite much speculation, the principal factors controlling concentrations of polycyclic aromatic hydrocarbons (PAH) in settled house dust (SHD) have not yet been identified. In response to recent reports that dust from pavement with coal-tar-based sealcoat contains extremely high concentrations of PAH, we measured PAH in SHD from 23 apartments and in dust from their associated parking lots, one-half of which had coal-tar-based sealcoat (CT). The median concentration of total PAH (T-PAH) in dust from CT parking lots (4760 microg/g, n = 11) was 530 times higher than that from parking lots with other pavement surface types (asphalt-based sealcoat, unsealed asphalt, concrete [median 9.0 microg/g, n = 12]). T-PAH in SHD from apartments with CT parking lots (median 129 microg/g) was 25 times higher than that in SHD from apartments with parking lots with other pavement surface types (median 5.1 microg/g). Presence or absence of CT on a parking lot explained 48% of the variance in log-transformed T-PAH in SHD. Urban land-use intensity near the residence also had a significant but weaker relation to T-PAH. No other variables tested, including carpeting, frequency of vacuuming, and indoor burning, were significant. PMID:20063893

  15. House Dust Mite Allergy in Korea: The Most Important Inhalant Allergen in Current and Future

    PubMed Central

    Jeong, Kyoung Yong; Park, Jung-Won

    2012-01-01

    The house-dust mite (HDM), commonly found in human dwellings, is an important source of inhalant and contact allergens. In this report, the importance of HDM allergy in Korea and the characteristics of allergens from dust mite are reviewed with an emphasis on investigations performed in Korea. In Korea, Dermatophagoides farinae is the dominant species of HDM, followed by D. pteronyssinus. Tyrophagus putrescentiae is also found in Korea, but its role in respiratory allergic disease in Korea is controversial. The relatively low densities of mite populations and concentrations of mite major allergens in dust samples from Korean homes, compared to westernized countries, are thought to reflect not only different climatic conditions, but also cultural differences, such as the use of 'ondol' under-floor heating systems in Korean houses. HDM are found in more than 90% of Korean houses, and the level of exposure to HDM is clinically significant. About 40%-60% of Korean patients suffering from respiratory allergies, and more than 40% of patients suffering from atopic dermatitis, are sensitized to HDM. Mite allergens can be summarized according to their inherent auto-adjuvant activities and/or their binding affinities to the adjuvant-like substances: proteolytic enzymes, lipid binding proteins, chitin binding proteins, and allergens not associated with adjuvant-like activity. In general, allergens with a strong adjuvant-like activity or adjuvant-binding activity elicit potent IgE reactivity. In Korea, Der f 2 is the most potent allergen, followed by Der f 1. Immune responses are modulated by the properties of the allergen itself and by the adjuvant-like substances that are concomitantly administered with the antigens. Characterization of allergenic molecules and elucidation of mechanisms by which adjuvant-like molecules modulate allergic reactions, not only in Korea but also worldwide, will provide valuable information on allergic diseases, and are necessary for the development of diagnostic tools and therapeutic strategies. PMID:23115727

  16. Lead Poisoning Prevention Tips

    MedlinePLUS

    ... can become contaminated from household dust or exterior soil. Both are known lead sources. Regularly wet-mop ... entering the house to prevent bringing lead-contaminated soil in from outside. Prevent children from playing in ...

  17. Characterizing the Peroxisome Proliferator-Activated Receptor (PPAR?) Ligand Binding Potential of Several Major Flame Retardants, Their Metabolites, and Chemical Mixtures in House Dust

    PubMed Central

    Fang, Mingliang; Webster, Thomas F.; Ferguson, P. Lee

    2014-01-01

    Background: Accumulating evidence has shown that some environmental contaminants can alter adipogenesis and act as obesogens. Many of these contaminants act via the activation of the peroxisome proliferator-activated receptor ? (PPAR?) nuclear receptor. Objectives: Our goal was to determine the PPAR? ligand binding potency of several major flame retardants, including polybrominated diphenyl ethers (PBDEs), halogenated phenols and bisphenols, and their metabolites. Ligand binding activity of indoor dust and its bioactivated extracts were also investigated. Methods: We used a commercially available fluorescence polarization ligand binding assay to investigate the binding potency of flame retardants and dust extracts to human PPAR? ligand-binding domain. Rosiglitazone was used as a positive control. Results: Most of the tested compounds exhibited dose-dependent binding to PPAR?. Mono(2-ethylhexyl) tetrabromophthalate, halogenated bisphenols and phenols, and hydroxylated PBDEs were found to be potent PPAR? ligands. The most potent compound was 3-OH-BDE-47, with an IC50 (concentration required to reduce effect by 50%) of 0.24 ?M. The extent of halogenation and the position of the hydroxyl group strongly affected binding. In the dust samples, 21 of the 24 samples tested showed significant binding potency at a concentration of 3 mg dust equivalent (DEQ)/mL. A 3–16% increase in PPAR? binding potency was observed following bioactivation of the dust using rat hepatic S9 fractions. Conclusion: Our results suggest that several flame retardants are potential PPAR? ligands and that metabolism may lead to increased binding affinity. The PPAR? binding activity of house dust extracts at levels comparable to human exposure warrants further studies into agonistic or antagonistic activities and their potential health effects. Citation: Fang M, Webster TF, Ferguson PL, Stapleton HM. 2015. Characterizing the peroxisome proliferator-activated receptor (PPAR?) ligand binding potential of several major flame retardants, their metabolites, and chemical mixtures in house dust. Environ Health Perspect 123:166–172;?http://dx.doi.org/10.1289/ehp.1408522 PMID:25314719

  18. How to minimize iron loss while decontaminating converter dust from lead.

    PubMed

    Moussavi, Mohsen; Fathikalajahi, Jamshid; Khalili, Fariba

    2011-12-01

    The purpose of this work was to decontaminate a converter flue dust from lead while minimizing the iron loss from the dust matrix. A physicochemical method based on a leaching cascade was applied to remove lead impurities with HCl. Finally, the lead-rich wastes generated at the end of the operations were further treated in order to meet the standards of waste disposal sites. The results show that lead could be removed from the dust with efficiencies of better than 90%. However, some iron was lost in these operations. It was noticed that under optimum conditions 8.5 g of iron would be lost as leachate per each gram of removed lead. It was also noticed that the lead-treated dust was more concentrated in iron and had less calcium. A number of parameters that could affect the amount of iron loss, such as acid dose, exposure time and temperature, were identified and the extent of the effects are presented. It was concluded that the lead content in the flue dust could practically be lowered to any level. It was also concluded that the difference between the solubility of lead chloride in cold and hot water, as well as the affinity of certain ligands such as Cl- and OH- to form stable complexes with lead ions, played a key role in this study. The lead-containing complexes in the leachate were identified to be predominantly PbCl3- and PbCl+. PMID:22439558

  19. Vacuum cleaning decreases the levels of mite allergens in house dust.

    PubMed

    Munir, A K; Einarsson, R; Dreborg, S K

    1993-08-01

    To investigate the capacity of chemical treatment of surfaces and the difference in capacity among common vacuum cleaners to reduce mite allergen content in house dust, we recruited 52 families with allergic children. Ten families used their central vacuum cleaners. Forty-two families were randomly divided into four groups with 10 or 11 families in each. These families used either new vacuum cleaners with either HEPA (High Efficiency Particulate Air) or micro-filters, or their own vacuum cleaners with either tannic acid or placebo. Dust samples were collected from carpets and upholstered furniture in the living rooms and from the mattresses of the children at Days 0, 7, 21, and 35. Der pI and Der fI allergens were determined by sandwich ELISA. After one week, tannic acid reduced the concentration of mite allergens/g of dust and the total amount/sampling area by 30% and 34%, respectively (p < 0.05), but there was no significant decrease in relation to placebo. After 5 weeks, central, HEPA- and micro-filter vacuum cleaners decreased the mite allergen concentration by 10-50% (p < 0.05) and the total amount of mite allergen from the investigated areas by 50-85% (p < 0.01). In relation to the placebo group the decrease was significant for HEPA- and micro-filter vacuums (p < 0.05). The total amount of mite allergens/sampling area was more significantly (p < 0.05) reduced than the concentration/g of dust. We conclude, that tannic acid reduces mite allergen concentrations in dust and total amount/sampling area for a short period of time.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8220802

  20. Analysis of House Dust and Children’s Hair for Pesticides: A Comparison of Markers of Ongoing Pesticide Exposure in Children

    PubMed Central

    Ostrea, Enrique M.; Villanueva-Uy, Esterlita; Bielawski, Dawn; Birn, Sarah; Janisse, James J.

    2012-01-01

    Background/Aim The long term study of the adverse effects of pesticides on child neuro development requires monitoring not only of initial, but ongoing pesticide exposure. Our aim was to compare house dust and children’s hair as environmental and biological markers of ongoing pesticide exposure in children. Design/Methods In a continuing NIH study on the adverse effects of prenatal pesticide exposure on child neurodevelopment, ongoing pesticide exposure after birth was measured in swept house dust and hair in the children at 4 years of age for propoxur and pyrethroids (transfluthrin, bioallethrin, cyfluthrin and cypermethrin) by gas chromatography/mass spectrometry. The prevalence and concentration of pesticides in the two matrices were compared. Results Prevalence of propoxur was higher in hair compared to house dust (p<0.001) whereas prevalence of the pyrethroids was higher (p<0.001) in house dust. The overall concentrations of the pyrethroids were also higher (p<0.007) in house dust compared to hair. There was a significant (p<0.001) correlation between dust and hair for bioallethrin and cypermethrin. Conclusions Ongoing exposure of children to environmental pesticides is sensitively detected by analysis of children’s hair and house dust. However, prevalence of propoxur was higher in hair compared to swept house dust, but the opposite was found for the pyrethroids. Thus, both matrices should be analyzed. There was a significant (p<0.001) correlation between house dust and hair for bioallethrin and cypermethrin. PMID:24288586

  1. [Acarex test and acarosan effect in house dust mite allergy in 2 year follow-up].

    PubMed

    Kersten, W; Stollewerk, D; von Wahl, P G

    1992-01-01

    Clinical investigations of the effect of the acaricide product Acarosan shows in a large collective of patients beneficial results, whereby the patients are examined up to three months after sanitation. The remaining patients of this study are followed up one and two years after sanitation in open clinical trials. Without exception Acarex test values decrease highly significant after three months, indicating the effective elimination of the house dust mites by Acarosan treatment and consequently the reduction of the allergen containing excreta. The values increase after one year, but after a repetition of the Acarosan treatment they decrease again to the level reached after the first sanitation. The best results are achieved by sanitation of carpets, less favourable results are obtained by treating matresses and upholstered furniture. After sanitation all patients with monovalent house dust mite sensitization report an improvement of their symptoms (eyes, nose, bronchi) up to two years. Drug consumption is variable and decreases over all for up to two years. Peak flow meter values improve in the first year and even further more in the second year. The clinical improvement does not depend on sex, living area or former immunotherapy. During the two year observation period immunologic parameters do not change. 25.6% of the patients show a negative provocation test after the first year and 57% after the second year. Side effects due to the sanitation or signs of sensitization against Acarosan are not observed. PMID:1546059

  2. Respiratory allergy caused by house dust mites: What do we really know?

    PubMed

    Calderón, Moisés A; Linneberg, Allan; Kleine-Tebbe, Jörg; De Blay, Frédéric; Hernandez Fernandez de Rojas, Dolores; Virchow, Johann Christian; Demoly, Pascal

    2014-11-22

    The house dust mite (HDM) is a major perennial allergen source and a significant cause of allergic rhinitis and allergic asthma. However, awareness of the condition remains generally low. This review assesses the links between exposure to HDM, development of the allergic response, and pathologic consequences in patients with respiratory allergic diseases. We investigate the epidemiology of HDM allergy to explore the interaction between mites and human subjects at the population, individual, and molecular levels. Core and recent publications were identified by using "house dust mite" as a key search term to evaluate the current knowledge of HDM epidemiology and pathophysiology. Prevalence data for HDM allergen sensitization vary from 65 to 130 million persons in the general population worldwide to as many as 50% among asthmatic patients. Heterogeneity of populations, terminology, and end points in the literature confound estimates, indicating the need for greater standardization in epidemiologic research. Exposure to allergens depends on multiple ecological strata, including climate and mite microhabitats within the domestic environment, with the latter providing opportunity for intervention measures to reduce allergen load. Inhaled mite aeroallergens are unusually virulent: they are able to activate both the adaptive and innate immune responses, potentially offering new avenues for intervention. The role of HDM allergens is crucial in the development of allergic rhinitis and asthma, but the translation of silent sensitization into symptomatic disease is still incompletely understood. Improved understanding of HDMs, their allergens, and their microhabitats will enable development of more effective outcomes for patients with HDM allergy. PMID:25457152

  3. The effectiveness of acupuncture compared to loratadine in patients allergic to house dust mites.

    PubMed

    Hauswald, Bettina; Dill, Christina; Boxberger, Jürgen; Kuhlisch, Eberhard; Zahnert, Thomas; Yarin, Yury M

    2014-01-01

    Background. The aim of this work was to evaluate the clinical effectiveness of acupuncture and its impact on the immune system in comparison to loratadine in the treatment of persistent allergic rhinitis caused by house dust mites. Methods. In this study, 24 patients suffering from persistent allergic rhinitis induced by house dust mites were treated either with acupuncture (n = 15) or with loratadine (n = 9). The evaluation of the data was based on the subjective and the objective rhinoconjunctivitis symptom scores, specific and total IgE, and interleukins (IL-4, IL-10, and IFN- ? ) as markers for the activity of Th1 or Th2 cells. Results. The treatments with acupuncture as well as with loratadine were considered effective in the patients' subjective assessment, whereby the effect of the acupuncture tended to be assessed as more persistent after the end of treatment. A change in the specific or the total IgE was not detectable in either group. The interleukin profile showed the tendency of an increasing IL-10 value in the acupuncture group. The results of the study show that the effectiveness of acupuncture is comparable to that of loratadine. Conclusion. Acupuncture is a clinically effective form of therapy in the treatment of patients suffering from persistent allergic rhinitis. The results indicate the probability of an immunomodulatory effect. PMID:24995021

  4. The Effectiveness of Acupuncture Compared to Loratadine in Patients Allergic to House Dust Mites

    PubMed Central

    Hauswald, Bettina; Dill, Christina; Boxberger, Jürgen; Kuhlisch, Eberhard; Zahnert, Thomas; Yarin, Yury M.

    2014-01-01

    Background. The aim of this work was to evaluate the clinical effectiveness of acupuncture and its impact on the immune system in comparison to loratadine in the treatment of persistent allergic rhinitis caused by house dust mites. Methods. In this study, 24 patients suffering from persistent allergic rhinitis induced by house dust mites were treated either with acupuncture (n = 15) or with loratadine (n = 9). The evaluation of the data was based on the subjective and the objective rhinoconjunctivitis symptom scores, specific and total IgE, and interleukins (IL-4, IL-10, and IFN-?) as markers for the activity of Th1 or Th2 cells. Results. The treatments with acupuncture as well as with loratadine were considered effective in the patients' subjective assessment, whereby the effect of the acupuncture tended to be assessed as more persistent after the end of treatment. A change in the specific or the total IgE was not detectable in either group. The interleukin profile showed the tendency of an increasing IL-10 value in the acupuncture group. The results of the study show that the effectiveness of acupuncture is comparable to that of loratadine. Conclusion. Acupuncture is a clinically effective form of therapy in the treatment of patients suffering from persistent allergic rhinitis. The results indicate the probability of an immunomodulatory effect. PMID:24995021

  5. Lead Paint, Toxic Torts, and the Housing Stock: A Case Study in Risk Assessment

    Microsoft Academic Search

    Roy J. Epstein; Brattle Square

    1998-01-01

    Numerous policymakers have accepted claims in the public health literature that the United States is in the middle of a serious epidemic of childhood lead poisoning, due primarily to lead paint in the housing stock. This article analyzes some of the most influential lead paint epidemiological studies from an economics perspective and finds evidence that the claimed effects of lead

  6. The prevalence of house dust mites, Dermatophagoides spp, and associated environmental conditions in homes in Ohio.

    PubMed

    Arlian, L G; Bernstein, I L; Gallagher, J S

    1982-06-01

    Abundance of the house dust mites, Dermatophagoides farinae and D. pteronyssinus, in various sites in the homes of dust-sensitive patients was sequentially monitored at approximately 3 wk intervals for 2 yr, and mite density was correlated with indoor physical and climatic factors. Significantly higher mite levels occurred on the most heavily used fabric-upholstered furniture and carpeted floor areas of the living/family room and bedrooms. Mattresses were not found to be the major foci for mites. No significant positive correlation was noted between mite abundance and frequency or thoroughness of cleaning, amount of dust, and age of furnishings or dwelling. Significantly higher mite levels occurred on carpeted floors than on noncarpeted floors. Successive vacuuming did not significantly reduce mite abundance. Mite density exhibited a seasonal fluctuation, with highest density occurring in the humid summer months and the lowest density during the dryer, late heating season. Live mites were more abundant than dead mites during the period when total abundance was high. In homes inhabited by both species, D. farinae was the dominant species, except in one home that had a significantly higher relative humidity. PMID:7076994

  7. Analysis of pesticides and PCBs in waste wood and house dust.

    PubMed

    Abb, M; Breuer, J V; Zeitz, C; Lorenz, W

    2010-09-01

    The use of the pesticides - DDT (1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane) and lindane (gamma-hexachlorocyclohexane) - and of PCBs (polychlorinated biphenyls) has been limited or forbidden for several decades. Nevertheless, due to their persistence and bioaccumulative potentials they are still ubiquitous in the environment. Therefore, the main objective of this study was to determine analytical methods to analyse the pesticides lindane and DDT, its metabolites DDD (1,1-dichloro-2,2-bis(4-chlorophenyl)ethane) and DDE (1,1-dichloro-2,2-bis(4-chlorophenyl)ethene), and PCBs in waste wood and house dust. An ultrasonic extraction was performed followed by a sample clean up by filtration or silica gel column. The prepared samples were measured by GC/MS. Quantification through internal standard calibration delivered low limits of detection. Specific amounts of the target compounds were detected in all analysed dust samples. The comparison of the contamination between dust samples of eastern Germany (former German Democratic Republic - GDR) and western Germany partly revealed significant differences of the contamination levels. Furthermore, it was examined whether older wooden material might cause a constant volatilisation of pesticides in apartments. Waste wood samples of different contamination categories were analysed. Apparently, these samples are potentially responsible for a constant DDX (?(DDT, DDD, DDE)) and lindane volatilisation, but not for PCBs. PMID:20709354

  8. Laboratory and Analytical Method Performance of Lead Measurements in Paint Chips, Soils, and Dusts

    Microsoft Academic Search

    Paul C. Schlecht; Jensen H. Groff; Amy Feng; Ruiguang Song

    1996-01-01

    The National Lead Laboratory Accreditation Program (NLLAP) recognizes laboratories capable of analyzing lead in paints, soils, and dusts. NLLAP requires successful participation in the Environmental Lead Proficiency Analytical Testing (ELPAT) program. For paint chip analyses, laboratory-to-laboratory variability is about 10% relative standard deviation (RSD) for lead levels near 0.5%, the HUD definition of lead-based paint. For soil analyses, RSDs are

  9. Immunomodulatory Effects of CpG Oligodeoxynucleotides on House Dust Mite-Induced Airway Inflammation in Mice

    Microsoft Academic Search

    Izumi Hirose; Hiroyuki Tanaka; Go Takahashi; Keiko Wakahara; Mayumi Tamari; Tatsuo Sakamoto; Seiji Kojima; Naoki Inagaki; Hiroichi Nagai

    2008-01-01

    Background: CpG oligodeoxynucleotides (CpG ODNs) are reported to protect against airway eosinophilia and hyperresponsiveness in animal models of asthma. However, little is known about the effects of CpG ODNs on house dust mites, one of the most common environmental allergens, causing allergic asthma. In the present study, we evaluated the immunomodulatory effects of CpG ODNs on the development of house

  10. IN-HOUSE CORROSION RESEARCH EMPHASIZING LEAD, COPPER AND IRON

    EPA Science Inventory

    Lead and copper are directly regulated via the "Lead and Copper Rule;" however, water suppliers must balance all water treatment processes in order to simultaneously comply with all regulations. Specific research needs for copper and lead chemistry still exist, as applications o...

  11. Superiority of the histamine release test above case history, prick test, and radio-allergosorbent test in predicting bronchial reagibility to the house dust mite in asthmatic children

    Microsoft Academic Search

    F. Wegner; R. Hockamp; A. Rutschke; B. Becker; D. Reinhardt

    1983-01-01

    Summary It was suggested that 28 asthmatic children be sensitized against the house dust mite according to a positive case history and\\/or a positive result of the prick test and the radio-allergosorbent test (RAST). When these children underwent a bronchial provocation test with house dust mite allergen, 19 responded with a bronchoconstriction whereas nine remained unaffected. With the positive results

  12. Henry and Fred Learn about Lead

    E-print Network

    Holsinger, Kent

    , an old house may contain lead paint. The dust and flakes from that paint are a serious health hazard simple rules to protect himself, Sue, and Fred from lead. Rule 1: Stay away from paint dust and paint flakes. Lead paint was banned for use in U.S. homes in 1978, but many houses and apartment buildings

  13. [The temporal variation of fine dust concentration in the air in fattening pig housing. Hygienic and occupational medicine aspects].

    PubMed

    Zeitler-Feicht, M H; Praml, G J; Riedel, H

    1991-03-01

    The temporal variation of airborne dust concentration (less than or equal to microns) was examined with an instrument operating on the nephelometer principle combined with a specifically adapted data processor in two pig fattening houses at night, at day and during feeding. Activities and factors affecting the dust level were noted. The measurement system allows the uptake and storage of values in the stable. For further processing, the data can be transmitted to a personal computer. In our experience the instrument is very suitable for the registration of airborne dust concentration in animal confinement buildings. Peak concentrations ranging up to 100 mg/m3 in intervals of 10 seconds could be measured. The data of a longer trial were averaged over 1.5 minutes. Animal activity has a great influence on the dust concentration. The highest mean concentration of dust with maximally 2.5 mg/m3 were determined at feeding time and when pigs were disturbed. The concentration of airborne dust particles was obviously lower at night than at day. A defect of the ventilation system, referable to the emission of feed dust, was disclosed by the continuous registration of air dust concentration, in one of the pig fattening houses. During the feeding periods, for a short time of less than 20 seconds, the dust concentration rises to 100 mg/m3 resp. 27 mg/m3 by dry resp. wet feeding. About 30 minutes after feeding the dust concentration was again in the average of 0.67 mg/m3. In conclusion the results were considered under hygienic and medical aspects. PMID:2049059

  14. Lead (Pb) in old Antarctic ice: Some from dust, some from other sources

    USGS Publications Warehouse

    Hinkley, T.

    2007-01-01

    Recently published data on amounts and isotopic compositions of lead (Pb) and on amounts of mineral dust in pre-industrial Antarctic ice can be further interpreted by means of simple calculations. These show that two distinct types of Pb were provided by the atmosphere to the continent in varying proportions during Pleistocene and Holocene time. One type of Pb is that contained in the mineral lattices of dust. It has non-radiogenic isotopic proportions. The other type of Pb is not associated with dust minerals, is more radiogenic, and is consistent with an origin in emissions from ocean island volcanoes worldwide, or from some Antarctic volcanoes.

  15. VIEASURING THE AMOUNT OF LEAD IN IN DOOR DUST: LONG-TERI DUSTFALL ACCUMULATION IN PETRI DISHES (A PILOT STUDY)

    Microsoft Academic Search

    John Wlodarczyk; Ruth Toneguzzi; Charles Gruszynski

    ead from dust is potentially the major contributor to blood lead levels in children living in urban environments in Australia' and is likely to make a substantial contribution to blood lead levels of children living in the vicinity of lead smelters. We undertook a trial of measuring dust in petri dishes to estimate the long-term flux of lead in indoor

  16. Depigmented and Polymerised House Dust Mite Allergoid: Allergen Content, Induction of IgG4 and Clinical Response

    Microsoft Academic Search

    M. T. Gallego; V. Iraola; M. Himly; D. S. Robinson; C. Badiola; J. C. García-Robaina; P. Briza; J. Carnés

    2010-01-01

    Background: Polymerised allergenic extracts (allergoids) are commonly used in allergen immunotherapy. Clinical efficacy and safety of these extracts have been demonstrated. Recently, allergen sequences have been identified by mass spectrometry in depigmented and polymerised (Dpg-Pol) extracts. The objectives of this study were to investigate the presence of allergens in Dpg-Pol extracts of house dust mite and to analyze the immunological

  17. Optimisation of a screening procedure for house dust mite numbers in carpets and preliminary application to buildings

    Microsoft Academic Search

    Stephen K. Brown

    1994-01-01

    The relative performances of the mobility and heat escape methods for measuring house dust mite numbers in carpet has been evaluated. The optimum method was found to be the mobility method for 24 hours at ambient temperatures which exhibited a mite collection efficiency of approximately 30%. Measurements in three dwellings showed that the method should be applied to carpet at

  18. The effect of sub-floor heating on house-dust-mite populations on floors and in furniture.

    PubMed

    de Boer, Rob

    2003-01-01

    It is well known that dehydrating conditions for house dust mites can be created by simply raising the temperature, causing loss of body water and eventually death. Thus, it can be expected that conditions for dust mites are less favourable on floors supplied with sub-floor heating. This was examined in a study of 16 houses with sub-floor heating and 21 without. The pattern of changes in air humidity and temperature on the floors was investigated and compared to known data of the tolerance of dust mites. Also the resident mite populations were compared. Floors with sub-floor heating had, on average, fewer mites, but the difference with unheated floors was small. It was remarkable that mite numbers were also lower in upholstered furniture. Another important observation was that some houses with sub-floor heating had high mite numbers, indicating that this type of heating is compatible with a thriving mite population. Temperature and humidity conditions of heated floors may allow mites not only to survive, but also to remain active in winter. A moderate increase in temperature, a moderate decrease in (absolute) air humidity, or a combination of both, will suffice to keep the humidity all winter below the Critical Equilibrium Humidity, the level of air humidity that is critical for mite growth and reproduction, hence for allergen production. However, it is argued that measures to suppress allergen production by house dust mites are likely to be far more effective if taken in summer rather than in winter. PMID:14635817

  19. Comparison of the Allergic Responses Induced by PeniciIlium chrysogenum and House Dust Mite Extracts in a Mouse Model

    EPA Science Inventory

    A report by the Institute of Medicine suggested that more research is needed to better understand mold effects on allergic disease, particularly asthma development. We compared the ability of the fungal Penicillium chrysogenum (PCE) and house dust mite (HDM) extracts to induce al...

  20. Basophils express a type 2 cytokine profile on exposure to proteases from helminths and house dust mites

    Microsoft Academic Search

    Clair Phillips; William R. Coward; David I. Pritchard; Colin R. A. Hewitt

    2003-01-01

    The proteolytic activities frequently as- sociated with sources of allergens and parasite se- cretions have been suggested as important immu- nomodulators. We have investigated whether the protease activity of the house dust mite allergen Der p1 and the secreted proteases of the hook- worm Necator americanus are able to directly in- duce type 2 cytokine production by basophils. Der p1

  1. House dust mite allergen induces asthma via Toll-like receptor 4 triggering of airway structural cells

    Microsoft Academic Search

    Hamida Hammad; Marcello Chieppa; Frederic Perros; Monique A Willart; Ronald N Germain; Bart N Lambrecht

    2009-01-01

    Barrier epithelial cells and airway dendritic cells (DCs) make up the first line of defense against inhaled substances such as house dust mite (HDM) allergen and endotoxin (lipopolysaccharide, LPS). We hypothesized that these cells need to communicate with each other to cause allergic disease. We show in irradiated chimeric mice that Toll-like receptor 4 (TLR4) expression on radioresistant lung structural

  2. MONITORING METHODS FOR POLYCYCLIC AROMATIC HYDROCARBONS AND THEIR DISTRIBUTION IN HOUSE DUST AND TRACK-IN SOIL

    EPA Science Inventory

    An analytical method was developed and employed to determine polycyclic aromatic hydrocarbons (PAH) in house dust and soil. he method was applied to the analysis of samples collected in an eight-home pilot study that was conducted in Columbus, OH, before and after the 1992/1993 h...

  3. Molecular Determinants for Antibody Binding on Group 1 House Dust Mite Allergens

    SciTech Connect

    Chruszcz, Maksymilian; Pomés, Anna; Glesner, Jill; Vailes, Lisa D.; Osinski, Tomasz; Porebski, Przemyslaw J.; Majorek, Karolina A.; Heymann, Peter W.; Platts-Mills, Thomas A.E.; Minor, Wladek; Chapman, Martin D. (INDOOR Bio.); (UV); (UVHS)

    2012-07-11

    House dust mites produce potent allergens, Der p 1 and Der f 1, that cause allergic sensitization and asthma. Der p 1 and Der f 1 are cysteine proteases that elicit IgE responses in 80% of mite-allergic subjects and have proinflammatory properties. Their antigenic structure is unknown. Here, we present crystal structures of natural Der p 1 and Der f 1 in complex with a monoclonal antibody, 4C1, which binds to a unique cross-reactive epitope on both allergens associated with IgE recognition. The 4C1 epitope is formed by almost identical amino acid sequences and contact residues. Mutations of the contact residues abrogate mAb 4C1 binding and reduce IgE antibody binding. These surface-exposed residues are molecular targets that can be exploited for development of recombinant allergen vaccines.

  4. Utilizing Pyrosequencing and Quantitative PCR to Characterize Fungal Populations among House Dust Samples

    PubMed Central

    Nonnenmann, Matthew W.; Coronado, Gloria; Thompson, Beti; Griffith, William C.; Hanson, John Delton; Vesper, Stephen; Faustman, Elaine M.

    2014-01-01

    Molecular techniques are replacing culturing and counting methods in quantifying indoor fungal contamination. Pyrosequencing offers the possibility of identifying unexpected indoor fungi. In this study, 50 house dust samples were collected from homes in the Yakima Valley, WA. Each sample was analyzed by quantitative PCR (QPCR) for 36 common fungi and by fungal tag-encoded flexible (FLX) amplicon pyrosequencing (fTEFAP) for these and additional fungi. Only 24 of the samples yielded amplified results using fTEFAP but QPCR successfully amplified all 50 samples. Over 450 fungal species were detected by fTEFAP but most were rare. Twenty-two fungi were found by fTEFAP to occur with at least an average of ? 0.5% relative occurrence. Many of these fungi seem to be associated with plants, soil or human skin. Combining fTEFAP and QPCR can enhance studies of fungal contamination in homes. PMID:22767010

  5. Acaricidal activities against house dust mites of spearmint oil and its constituents.

    PubMed

    Yang, Ji-Yeon; Kim, Min-Gi; Lee, Sung-Eun; Lee, Hoi-Seon

    2014-02-01

    The aim of this study was to evaluate the acaricidal activities of spearmint oil and carvone derivatives against house dust mites using contact and fumigant toxicity bioassays to replace benzyl benzoate as a synthetic acaricide. Based on the LD50 values, the contact toxicity bioassay revealed that dihydrocarvone (0.95 and 0.88?µg/cm2) was 7.7 and 6.8 times more toxic than benzyl benzoate (7.33 and 6.01?µg/cm2) against Dermatophagoides farinae and Dermatophagoides pteronyssinus, respectively, followed by carvone (3.78 and 3.23?µg/cm2), spearmint oil (5.16 and 4.64?µg/cm2), carveol (6.00 and 5.80?µg/cm2), and dihydrocarveol (8.23 and 7.10?µg/cm2). Results of the fumigant toxicity bioassay showed that dihydrocarvone (2.73 and 2.16?µg/cm2) was approximately 4.0 and 4.8 times more effective than benzyl benzoate (11.00 and 10.27?µg/cm2), followed by carvone (6.63 and 5.78?µg/cm2), carveol (7.58 and 7.24?µg/cm2), spearmint oil (9.55 and 8.10?µg/cm2), and dihydrocarveol (9.79 and 8.14?µg/cm2). Taken together, spearmint oil and carvone derivatives are a likely viable alternative to synthetic acaricides for managing house dust mites. PMID:24488719

  6. Multi-analyte method for the analysis of various organohalogen compounds in house dust.

    PubMed

    Lankova, Darina; Svarcova, Andrea; Kalachova, Kamila; Lacina, Ondrej; Pulkrabova, Jana; Hajslova, Jana

    2015-01-01

    In the present study, a novel analytical approach for the simultaneous determination of 27 brominated flame retardants (BFRs), namely polybrominated diphenyl ethers (PBDEs), isomers of hexabromocyclododecane (HBCD), tetrabromobisphenol A (TBBPA) and several novel BFRs (NBFRs), together with 18 perfluoroalkyl substances (PFASs) in indoor dust was developed and validated. To achieve integrated isolation of analytes from the sample and their fractionation, a miniaturized method based on matrix solid phase dispersion (MSPD) was employed. Principally, after mixing the dust (<0.1 g) with the Florisil(®), the mixture was applied on the top of a sorbent (Florisil(®)) placed in glass column and then analytes were eluted using solvents with different polarities. For the identification/quantification of target compounds largely differing in polarity, complementary techniques represented by gas and liquid chromatography coupled to tandem mass spectrometry (GC-MS/MS and LC-MS/MS) were used. The results of validation experiments, which were performed on the SRM 2585 material (for PBDEs, HBCDs and TBBPA), were in accordance with the certified/reference values. For other analytes (NBFRs and PFASs), the analysis of an artificially contaminated blank dust sample was realized. The method recoveries for all target compounds ranged from 81 to 122% with relative standard deviations lower than 21%. The quantification limits were in the range of 1-25 ng g(-1) for BFRs and 0.25-1 ng g(-1) for PFASs. Finally, 18 samples (6 households × 3 sampling sites) were analyzed. The high variability between concentrations of PFASs and BFRs in the dust samples from various households as well as collecting sites in a respective house was observed. The total amounts of PFASs and BFRs were in the range of 1.58-236 ng g(-1) (median 10.6 ng g(-1)) and 39.2-2320 ng g(-1) (median 325 ng g(-1)), respectively. It was clearly shown that dust from the indoor environment might be a significant source of human exposure to various organohalogen pollutants. PMID:25479868

  7. Can house dust mite-triggered atopic dermatitis be alleviated using acaricides?

    PubMed

    Cameron, M M

    1997-07-01

    House dust mite (HDM) allergens are the most important triggers for atopic dermatitis. Reducing exposure to these allergens may alleviate clinical symptoms. Chemicals with acaricidal activity have been used to treat upholstered furniture, carpets and bedding with the aim to reduce HDM allergen exposure. These chemicals, by reducing HDM, can decrease the concentration of mite allergens in dust but improvements in clinical symptoms are not always apparent. Clinical improvement is more likely to occur if bedding has been treated rather than carpets and upholstery. Future control strategies should be aimed at treating bedding. Permethrin is a very efficient killer of mites. It is used topically to treat scabies and head lice and is impregnated in bed nets to prevent mosquito bites. Even when applied to the skin in high concentrations, it has a very low toxicity in humans and other mammals. Permethrin-impregnated bedding may prove to be the best control method in the treatment of HDM allergen-triggered atopic conditions. PMID:9274618

  8. Seasonal variability of culturable fungal genera in the house dust of inner-city residences.

    PubMed

    Cho, Sook Ja; Ramachandran, Gurumurthy; Banerjee, Sudipto; Ryan, Andrew D; Adgate, John L

    2008-12-01

    House dust samples were collected up to six times over a 1-year period to explore seasonal variability of individual fungal genera in inner-city households in Minneapolis, Minnesota. General linear mixed-effects models were used to explore the variability of 13 fungal genera (Cladosporium, yeasts, Aureobasidium, Alternaria, Penicillium, Epicoccum, Mucor, Rhodotorula, Aspergillus, sterile fungi, Phoma, Pithomyces, and Fusarium) found in more than 20% of total dust samples. The five most common fungi (% of samples detected) were Cladosporium (81%), yeasts (63%), Aureobasidium (57%), Alternaria (56%), and Penicillium (55%), with the remaining genera found in 20-50% of the samples. When expressed as frequency of occurrence (%), genus fraction of total fungal concentration (%), or concentration of individual genera (CFU/g), these five genera also varied substantially by season. In contrast, Aureobasidium, Fusarium, and Mucor levels remained relatively constant throughout the year. The observed concentrations of the five most common fungal genera were higher than levels associated with increased respiratory symptoms reported in previous studies. Our results indicate that seasonal variability in common fungal genera is large: within-home to between-home variance ratios of Penicillium (4.1), Alternaria (4.9), Cladosporium (7.1), and yeasts (20.3) were substantially larger than that observed for total fungi (2.5). These results suggest that future studies attempting to link individual fungal genera to health effects need to characterize and control for this seasonal variability. PMID:18932081

  9. Childhood Lead Poisoning What Is the Problem?

    E-print Network

    .S. children are lead- based paint and lead-contaminated dust found in deteriorating buildings. Lead in the United States have deteriorated leaded paint and elevated levels of lead-contaminated house dust. More (making stained-glass windows, making pottery, and painting); and · soil contaminated by lead paint chips

  10. Bioavailability of arsenic in soil and house dust impacted by smelter activities following oral administration in cynomolgus monkeys.

    PubMed

    Freeman, G B; Schoof, R A; Ruby, M V; Davis, A O; Dill, J A; Liao, S C; Lapin, C A; Bergstrom, P D

    1995-12-01

    This study was conducted to determine the extent of arsenic (As) absorption from soil and house dust impacted by smelter activities near Anaconda, Montana. Female cynomolgus monkeys were given a single oral administration via gelatin capsules of soil (0.62 mg As/kg body wt) or house dust (0.26 mg As/kg body wt), or soluble sodium arsenate by the gavage or intravenous route of administration (0.62 mg As/kg body wt) in a crossover design with a minimum washout period of 14 days. Urine, feces, and cage rinse were collected at 24-hr intervals for 168 hr. Blood was collected at specified time points and area under the curves (AUCs) was determined. Arsenic concentrations for the first 120 hr, representing elimination of greater than 94% of the total administered dose for the three oral treatment groups, were < 0.021 to 4.68 micrograms/ml for the urine and < 0.24 to 31.1 micrograms/g for the feces. In general, peak concentrations of As in the urine and feces were obtained during the collection intervals of 0-24 and 24-72 hr, respectively. The main pathway for excretion of As for the intravenous and gavage groups was in the urine, whereas for the soil and dust groups, it was in the feces. Mean absolute percentage bioavailability values based on urinary excretion data were 68, 19, and 14% for the gavage, house dust, and soil treatments, respectively, after normalization of the intravenous As recovery data to 100%. Corresponding absolute bioavailability values based on blood were 91, 10, and 11%. The bioavailability of soil and house dust As relative to soluble As (by gavage) was between 10 and 30%, depending upon whether urinary or blood values were used. These findings suggest that risks associated with the ingestion of As in soil or dust will be reduced compared to ingestion of comparable quantities of As in drinking water. PMID:8835231

  11. Polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD) and "novel" brominated flame retardants in house dust in Germany.

    PubMed

    Fromme, H; Hilger, B; Kopp, E; Miserok, M; Völkel, W

    2014-03-01

    Brominated flame retardants (BFRs) are used in a wide variety of products such as electronic devices, upholstery and carpets and in insulation boards. The study presented here aimed to quantify the amounts of BFRs in house dust in Germany. For this purpose 20 residences' dust samples were collected from vacuum cleaner bags and analysed with LC-MS/MS and simultaneously with GC/MS. Using GC/MS, the median (95th percentile) concentrations of PBDEs (sum of tetra- to hepta-congeners), BDE 209, ?-HBCD (sum of three congeners), and decabromodiphenylethane (DBDPE) were 42ng/g (230ng/g), 950ng/g (3426ng/g), 335ng/g (1545ng/g), and 146ng/g (1059ng/g), respectively. Using LC-MS/MS some "novel" flame retardants were found in median concentrations of 343ng/g (bis(2-ethyl-1-hexyl)tetrabromophthalate, TBPH), and 28ng/g (tetrabromobisphenol A, TBBPA). Whilst 1,2-bis-(2,4,6-tribromophenoxy)ethane (BTBPE) and 2-ethyl-1-hexyl-2,3,4,5-tetrabromobenzoate (EH-TBB) could not be detected. Based on these measurements an exposure assessment for the sum of tetra- to heptabrominated congeners, BDE 209, and ?-HBCD resulted in a "high" daily intake for toddlers (based on 95th percentiles) of 1.2ng/kg b.w., 0.69ng/kg b.w., and 8.9ng/kg b.w., respectively. For TBPH the "high" intake was calculated at 4.1ng/kg b.w. and for DBDPE at 5.3ng/kg b.w. A clear tendency was observed to apply "novel" BFRs in Germany. Moreover, the results suggest that the recent exposure to PBDEs and HBCD via house dust in Germany is well below the levels that are associated with health effects. For the "novel" brominated flame retardants such an assessment is not possible due to limited toxicological information. PMID:24368294

  12. Tracing geogenic and anthropogenic sources in urban dusts: Insights from lead isotopes

    NASA Astrophysics Data System (ADS)

    Del Rio-Salas, R.; Ruiz, J.; De la O-Villanueva, M.; Valencia-Moreno, M.; Moreno-Rodríguez, V.; Gómez-Alvarez, A.; Grijalva, T.; Mendivil, H.; Paz-Moreno, F.; Meza-Figueroa, D.

    2012-12-01

    Tracing the source of metals in the environment is critical to understanding their pollution level and fate. Geologic materials are an important source of airborne particulate matter, but the contribution of contaminated soil to concentrations of Pb in airborne dust is not yet widely documented. To examine the potential significance of this mechanism, surface soil samples were collected, as well as wind-transported dust trapped at 1 and 2 m height at seven different locations including residential, industrial, high-traffic and rural sites. Samples of dust deposited on roofs from 24 schools were also obtained and analyzed for Pb isotope ratios. Spatial distribution of Pb of airborne and sedimented dust suggests a process dominated by re-suspension/sedimentation, which was controlled by erosion, traffic and topography of the urban area. Anthropogenic lead input in the city grades outward the urban zone toward geogenic values. Our results shows that Pb-isotopic signatures of leaded gasoline are imprinted in dust sedimented on roofs. Considering that leaded-gasoline has not been in use in Mexico since two decades ago, this signature shows not only a Pb-legacy in soil, but also a re-suspension process affecting air column below 3 m in height. The combination of the 207Pb/206Pb data of the surrounding rocks and urban dust, reveal three well-defined zones with remarkable anthropogenic influence, which correspond to the oldest urban sectors. This work highlights the importance of spatial characterization of metals in particles suspended below a height of 3 m of the airborne column, a fact that should be considered to identify exposure paths to humans and the potential risks. Lead isotope signatures allowed the identification of geogenic and anthropogenic emission sources for dust, a matter that deserves consideration in the efforts to control airborne metal emissions.

  13. Skin-associated Bacillus, staphylococcal and micrococcal species from the house dust mite, Dermatophagoides pteronyssinus and bacteriolytic enzymes.

    PubMed

    Tang, Vivian H; Chang, Barbara J; Srinivasan, Ambuja; Mathaba, Leslie T; Harnett, Gerald B; Stewart, Geoffrey A

    2013-12-01

    Dust mites produce bacteriolytic enzymes, one of which belongs to the NlpC/P60 superfamily comprising bacterial and fungal proteins. Whether this enzyme is derived from the mite or from mite-associated microbes is unclear. To this end, the bacteriology of mites per se, and carpet and mattress dust from a group of asthmatic children and their parents was investigated. Dust from parents' and children's mattresses yielded significantly more colony forming units compared with dust from their corresponding carpets. Zymography demonstrated some dusts contained bacteriolytic enzymes, and in nine of the twelve dust samples from three of five houses examined, a prominent bacteriolytic band was obtained that corresponded to the mite band, although in one home, other lytic bands were detected. Fifty bacterial isolates were obtained from surface-sterilised, commercially obtained Dermatophagoides pteronyssinus. 16S rRNA, tuf and rpoB gene sequencing of nine Gram-positive isolates identified them as Bacillus cereus, B. licheniformis, Staphylococcus aureus, S. epidermidis, S. capitis and Micrococcus luteus, known human skin commensals. 16S rRNA sequence homologies of four of the nine isolates identified as B. licheniformis formed a distinct phylogenetic cluster. All species secreted lytic enzymes during culture although the lytic profiles obtained differed between the rods and the cocci, and none of the bands detected corresponded to those observed in dust or mites. In conclusion, mites harbour a variety of bacterial species often associated with human skin and house dusts contain bacteriolytic enzymes that may be mite-derived. The identification of a novel cluster of B. licheniformis isolates suggests an ecological adaptation to laboratory-reared D. pteronyssinus. It remains to be determined whether the previously described mite-associated 14 K lytic enzyme is derived from a microbial source. PMID:23783892

  14. ASTM sampling methods and analytical validation for lead in paint, dust, soil, and air

    SciTech Connect

    Ashley, K.; Schlecht, P.C. [Dept. of Health and Human Services, Cincinnati, OH (United States); Song, R.; Feng, A. [Computer Sciences Corp., Cincinnati, OH (United States); DeWalt, G. [QuanTech, Rosslyn, VA (United States); McKnight, M.E. [National Inst. of Standards and Technology, Gaithersburg, MD (United States)

    1996-12-31

    ASTM Subcommittee E06.23 on Abatement/Mitigation of Lead Hazards has developed a number of standards that are concerned with the sampling of leas in environmental media, namely paint, dust, soil and airborne particulate. An ASTM practice for the collection of airborne particulate lead in the workplace has been published. New ASTM standards for the collection of dry paint film samples, surface soil samples, and surface dust wipe samples for subsequent lead analysis have also been promulgated. Other draft standards pertinent to lead sampling are under development. The ASTM standards concerned with lead sample collection are accompanied by separate sample preparation standard practices and a standard analysis method. Sample preparation and analytical methods have been evaluated by interlaboratory testing; such analyses may be used to assess the efficacy of sampling protocols.

  15. Commercial dry dog food in the north central United States is not contaminated by Dermatophagoides house dust mites.

    PubMed

    DeBoer, D J; Schreiner, T A

    2001-08-01

    Contamination of home-stored cereal grain food products with Dermatophagoides spp. house dust mites (HDM) was reported recently, along with anaphylaxis after consumption of these foods by dust mite-allergic people. We hypothesized that commercial dry dog food could become similarly contaminated, particularly if stored improperly, and could eventually contribute to allergic signs in dogs. Newly purchased bags of dry dog food (n = 30), from a variety of sources and manufacturers, and client samples of dry dog food (n = 50), stored under a variety of conditions, were obtained. Food samples were extracted in aqueous buffer, and extracts were assayed using ELISA for Dermatophagoides group II (Der II) allergen, as a marker for the presence of HDM. Der II allergen was not detected in any of the 30 newly purchased or 50 stored samples tested. Positive control samples consisting of house dust or dog food mixed with house dust, similarly extracted, and Dermatophagoides commercial allergen extract were positive for Der II in the same assay. We could find no evidence of HDM contamination in newly purchased or stored commercial dry dog food in the north central United States. PMID:11493401

  16. Lead

    MedlinePLUS

    ... Lead Epidemiology Surveillance Program (ABLES) Lead in the environment Agency for Toxic Substances and Disease Registry (ATSDR) Department of Housing and Urban Development (HUD) U.S. Environmental Protection Agency (EPA) Healthy Homes ...

  17. House dust bioactivities predict skin prick test reactivity for children with high risk of allergy

    PubMed Central

    Kim, Haejin; Tse, Kevin; Levin, Linda; Bernstein, David; Reponen, Tiina; LeMasters, Grace; Lummus, Zana; Horner, Anthony A.

    2013-01-01

    Background Although evidence suggests that ambient exposures to endotoxin and other immunostimulants during early life influence allergic risk, efforts to understand this host-environment relationship have been hampered by a paucity of relevant assays. Objectives These investigations determined whether parameters of house dust extract (HDE) bioactivity were predictive of allergen skin prick test (SPT) reactivity for infants at high risk of allergy participating in the Cincinnati Childhood Allergy and Air Pollution Study (CCAAPS). Methods We conducted a nested case-control study, selecting 99 CCAAPS children who had positive SPT results to at least 1 aeroallergen at age 3 years and 101 subjects with negative SPT results. HDEs were prepared from dust samples collected from the subjects' homes at age 1 year. Murine splenocytes and bone marrow–derived dendritic cells were incubated with HDEs, and supernatant cytokine concentrations were determined by means of ELISA. Alternatively, bone marrow–derived dendritic cells were preincubated with HDEs, and then LPS-induced IL-6 responses were assessed. HDE endotoxin levels were determined by using the limulus amebocyte lysate assay. Results HDEs derived from the homes of children with positive (cases) and negative (control subjects) SPT results had similar bioactivities. However, when cases were considered in isolation, HDEs with higher levels of bioactivity were significantly associated with children who had lower numbers of positive SPT results. Analogous statistical analyses did not identify any association between HDE endotoxin levels and the aeroallergen sensitization profiles of children included in this study. Conclusion HDE immunostimulatory activities predicted the aeroallergen sensitization status of CCAAPS subjects better than HDE endotoxin levels. These results provide the first published evidence that HDE bioassays have clinical relevance in predicting atopic risk. PMID:22385634

  18. Removal of lead paint from old housing: the need for a new approach

    Microsoft Academic Search

    J J Chisolm; J. J. Jr

    1986-01-01

    Considerations for the development of criteria for safe and effective methods for removal of lead-based paints and dusts from exposed residential surfaces include the following: residential buildings should be classified according to the degree of deterioration, taking into account not only the presence of scaling paint but also structural soundness, present and potential water damage, and the condition of the

  19. Exposure assessment of organophosphorus and organobromine flame retardants via indoor dust from elementary schools and domestic houses.

    PubMed

    Mizouchi, Shigekazu; Ichiba, Masayoshi; Takigami, Hidetaka; Kajiwara, Natsuko; Takamuku, Toshiyuki; Miyajima, Toru; Kodama, Hiroki; Someya, Takashi; Ueno, Daisuke

    2015-03-01

    To assess the exposure of flame retardants (FRs) for school-children, organophosphorus flame retardants and plasticizers (PFRs) and organobromine flame retardants (BFRs) were determined in the indoor dust samples collected from elementary schools and domestic houses in Japan in 2009 and 2010. PFRs were detected in all the dust samples analyzed and the highest concentration of total PFRs was thousand-fold higher than that of BFRs. Among the PFRs, tris(butoxyethyl)phosphate (TBOEP) showed the highest concentration with a median (med.) of 270,000 ng g(-1) dry weight (3700-5,500,000 ng g(-1) dry weight), followed by tris(methylphenyl)phosphate (TMPPs)>triphenyl phosphate (TPHP)=tris(1,3-dichloro-2-propyl)phosphate (TDCIPP)=tris(2-chloroisopropyl)phosphate (TCIPP)=tris(2chloroethyl)phosphate (TCEP)>ethylhexyl diphenyl phosphate (EHDPP). Significantly higher concentrations of TBOEP, tri-n-butyl phosphate (TNBP), TPHP, TMPPs, and total-PFRs were found in dust samples from elementary schools than from domestic houses. It might be due to that higher concentrations of TBOEP (as leveling agent) were detected from the floor polisher/wax products collected in those elementary schools. On the other hand, significantly higher concentrations of TCEP, TCIPPs, and total chloroalkyl-PFRs were found in domestic houses than in elementary schools. Exposure assessments of PFRs via indoor dust from elementary schools and domestic houses were conducted by calculating the hazard quotient (HQ). Among PFRs, HQs for TBOEP exceeded 1 (higher than reference dose: RfD) and its highest value was 1.9. To reduce the intake of TBOEP by school-children, it is recommended that the use of floor polisher/wax containing TBOEP be reduced in schools. PMID:25532762

  20. Generation of anaphylatoxins through proteolytic processing of C3 and C5 by house dust mite protease

    Microsoft Academic Search

    Keishi Maruo; Takaaki Akaike; Tomomichi Ono; Tatsuya Okamoto; Hiroshi Maeda

    1997-01-01

    Background: The group 3 allergen of Dermatophagoides species (Der p 3 and Der f 3) has been identified as a 30 kd trypsin-like protease of the house dust mite. We previously showed that the 30 kd protease from Dermatophagoides farinae (Df-protease) could activate the bradykinin-generating cascade and exacerbate inflammatory reactions. Objective: The purpose of this study was to determine whether

  1. Evaluation of the Nasal Provocation Test for Its Necessity in the Diagnosis of Nasal Allergy to House Dust Mite

    Microsoft Academic Search

    E. Kirerleri; N. Guler; Z. Tamay

    1 SUMMARY The aim of this study was to evaluate rhinomanometric responses to nasal allergen provocation in children with allergic rhinitis sensitized to house dust mite. We studied 51 children, aged 6-16 years (mean: 11.5 ± 2.6 years), with clinical symptoms of perennial allergic rhinitis without asthma and 20 non-atopic healthy controls in the same age range (mean: 11.8 ±

  2. Reduction of the in vivo allergenicity of Der p 2, the major house-dust mite allergen, by genetic engineering

    Microsoft Academic Search

    Kuan-Wei Chen; Gudrun Fuchs; Karoline Sonneck; Anna Gieras; Ines Swoboda; Nikolas Douladiris; Birgit Linhart; Marija Jankovic; Tea Pavkov; Walter Keller; Nikolaos G. Papadopoulos; Peter Valent; Rudolf Valenta; Susanne Vrtala

    2008-01-01

    The major allergen of the house-dust mite Dermatophagoides pteronyssinus, Der p 2, is recognized by approximately 90% of mite-allergic patients.We have produced two recombinant fragments of Der p 2 comprising aa 1–53 and aa 54–129 and a hybrid molecule (aa 54–129+1–53), combining the two fragments in inverse order, by genetic engineering. The recombinant Der p 2 derivatives were expressed in

  3. 908 The effect of specific immunotherapy on T cell receptor repertoire in patients with allergy to house dust mite

    Microsoft Academic Search

    K. Sade; E Fireman; A. Levy; Y Levo; S Kivity

    2000-01-01

    Background: The precise mechanism of specific immunotherapy (SIT), long used for treating allergic diseases, remains undefined.SIT was shown to act by modifying the immune response of T lymphocytes to antigens.We examined the effect of SIT on the expression and use V-alpha, -beta, -gamma and -delta chains of T-cell receptors (TCR) in patients allergic to house-dust mite. Methods: Peripheral venous blood

  4. Most Personal Exposure to House Dust Mite Aeroallergen Occurs during the Day

    PubMed Central

    Tovey, Euan R.; Willenborg, Christiana M.; Crisafulli, Daniele A.; Rimmer, Janet; Marks, Guy B.

    2013-01-01

    Background The bed is commonly regarded as the main site of house dust mite exposure; however this has not been directly established by continuous measurements. The objective of this study was to determine the pattern of personal exposure to mite aeroallergen over 24 hours. Methods 12 adults each collected 9 sequential samples (8 during the day, mean 115 mins, and one overnight, mean 514 mins) over 24 hours using a portable air-pump (2L/min) connected to an IOM filter located on the shoulder during the day and on the bed head overnight. Samples were analysed for mite allergen Der p 1 by ELISA. Location and activity were recorded. A mixed model analysis was performed to determine exposure as a function of 14 categories of activity. Results Personal aeroallergen exposure differed widely over time, both within and between subjects. The highest average exposure (1117 pg/m3, 95% CI: 289-4314) occurred on public transport and the lowest overnight in bed (45 pg/m3, 95% CI: 17-17), which contributed only 9.8% (95% CI: 4.4%-15.1%) of total daily exposure. Aeroallergens were not related to bed reservoirs. Conclusion The study challenges the current paradigm that the bed is the main site of HDM exposure and instead suggests most exposure occurs in association with domestic activity and proximity to other people. Effective mite interventions, designed to improve asthma outcomes, need to first identify and then address the multiple sources of aeroallergen exposure. PMID:23894558

  5. House Dust Mite Der p 1 Effects on Sinonasal Epithelial Tight Junctions

    PubMed Central

    Henriquez, Oswaldo A.; Beste, Kyle Den; Hoddeson, Elizabeth K.; Parkos, Charles A.; Nusrat, Asma; Wise, Sarah K.

    2013-01-01

    Background Epithelial permeability is highly dependent upon the integrity of tight junctions, cell-cell adhesion complexes located at the apical aspect of the lateral membrane of polarized epithelial cells. We hypothesize that sinonasal epithelial exposure to Der p 1 house dust mite antigen decreases expression of tight junction proteins (TJPs), representing a potential mechanism for increased permeability and presentation of antigens across the sinonasal epithelial layer. Methods Confluent cultured primary human sinonasal epithelial cells were exposed to recombinant Der p 1 antigen versus control, and transepithelial resistance measurements were performed over 24 hours. Antibody staining for a panel of tight junction proteins was examined with immunofluorescence/confocal microscopy and Western blotting. Tissue for these experiments was obtained from 4 patients total. Results Der p 1 exposed sinonasal cells showed a marked decrease in transepithelial resistance when compared to control cells. In addition, results of Western immunoblot and immunofluorescent labeling demonstrated decreased expression of TJPs claudin-1 and junction adhesion molecule-A (JAM-A) in Der p 1 exposed cultured sinonasal cells versus controls. Conclusion Der p 1 antigen exposure decreases sinonasal epithelium TJP expression, most notably seen in JAM-A and claudin-1 in these preliminary experiments. This decreased TJP expression likely contributes to increased epithelial permeability and represents a potential mechanism for transepithelial antigen exposure in allergic rhinitis. PMID:23592402

  6. Orchestration of an Uncommon Maturation Cascade of the House Dust Mite Protease Allergen Quartet

    PubMed Central

    Dumez, Marie-Eve; Herman, Julie; Campizi, Vincenzo; Galleni, Moreno; Jacquet, Alain; Chevigné, Andy

    2014-01-01

    In more than 20% of the world population, sensitization to house dust mite allergens triggers typical allergic diseases such as allergic rhinitis and asthma. Amongst the 23 mite allergen groups hitherto identified, group 1 is cysteine proteases belonging to the papain-like family whereas groups 3, 6, and 9 are serine proteases displaying trypsin, chymotrypsin, and collagenolytic activities, respectively. While these proteases are more likely to be involved in the mite digestive system, they also play critical roles in the initiation and in the chronicity of the allergic response notably through the activation of innate immune pathways. All these allergenic proteases are expressed in mite as inactive precursor form. Until recently, the exact mechanisms of their maturation into active proteases remained to be fully elucidated. Recent breakthroughs in the understanding of the activation mechanisms of mite allergenic protease precursors have highlighted an uncommon and unique maturation pathway orchestrated by group 1 proteases that tightly regulates the proteolytic activities of groups 1, 3, 6, and 9 through complex intra- or inter-molecular mechanisms. This review presents and discusses the currently available knowledge of the activation mechanisms of group 1, 3, 6, and 9 allergens of Dermatophagoides pteronyssinus laying special emphasis on their localization, regulation, and interconnection. PMID:24744761

  7. GPR17 Regulates Immune Pulmonary Inflammation Induced By House Dust Mite

    PubMed Central

    Maekawa, Akiko; Xing, Wei; Austen, K. Frank; Kanaoka, Yoshihide

    2014-01-01

    Antagonists of the type 1 cysteinyl leukotriene receptor (CysLT1R) are efficacious for bronchoconstriction in humans with bronchial asthma; however, the clinical response to these drugs is heterogeneous. In particular, how CysLT1R expression and function are constitutively regulated in vivo is not known. Here we show that a 7-transmembrane receptor GPR17 negatively regulates the CysLT1R-mediated inflammatory cell accumulation in the bronchoalveolar lavage fluid and lung, the levels of IgE and specific IgG1 in serum, and Th2/Th17 cytokine expression in the lung after intranasal sensitization and challenge with house dust mite (Df) in mice. Sensitization of naďve wild-type recipients with Df-pulsed bone marrow-derived dendritic cells (BMDCs) of each genotype or sensitization of each genotype with Df-pulsed wild-type BMDCs and Df challenge revealed markedly increased pulmonary inflammatory and serum IgE responses for GPR17-deficient mice as compared to wild-type mice and reduced responses in the genotypes lacking CysLT1R. These findings reveal a constitutive negative regulation of CysLT1R functions by GPR17 in both the antigen presentation and downstream phases of allergic pulmonary inflammation. PMID:20574000

  8. Production of Egg Yolk Antibodies Specific to House Dust Mite Proteins

    PubMed Central

    Lee, Kyung Eun; Han, Beom Ku; Han, Jae Yong; Hong, Jung Yeon; Kim, Mi Na; Heo, Won Il; Sohn, Myung Hyun; Kim, Kyung Won

    2014-01-01

    Purpose House dust mites (HDMs) are an important source of indoor allergens associated with asthma, rhinitis and atopic dermatitis. Chicken immunoglobulin (Ig) Y is known to be a good alternative to mice and rabbit antibody production. In this study, we produced IgYs specific to HDMs and investigated their IgE immunoreactivities. Materials and Methods Total IgYs were isolated from the yolks of White Leghorn hens immunized with either Dermatophagoides pteronyssinus or D. farinae protein extract. Control antibodies were separated from the yolks of immunized hens with phosphate buffered saline. IgYs specific to HDMs were analyzed using enzyme-linked immunosorbent assay and Western blotting analysis. Results The concentration of egg IgY specific to D. farinae in an immunized hen increased and the highest achieved was 661.3 ug/mg (per an egg) on day 47, compared with 760 ug/mg IgY specific to D. pteronyssinus on day 16. The D. pteronyssinus or D. farinae-specific IgY was detected by binding of each mite proteins, and their immunoreactivities were elevated dependent of the specific IgY concentration. Conclusion IgY specific to HDMs may be a promising antibody for immunological diagnosis as well as identification of possible resistance relating to HDM allergy. PMID:24954330

  9. Effectiveness of lead-hazard control interventions on dust lead loadings: Findings from the evaluation of the HUD Lead-Based Paint Hazard Control Grant Program

    Microsoft Academic Search

    Sherry L. Dixon; Jonathan W. Wilson; C. Scott Clark; Warren A. Galke; Paul A. Succop; Mei Chen

    2005-01-01

    From 1994 to 1999, the Evaluation of the US Department of Housing and Urban Development Lead-Based Paint Hazard Control Grant Program studied the intervention experiences of over 2800 homes in 11 states in the USA. Each interior intervention was categorized as (in order of increasing intensity) (a) cleaning\\/spot painting; (b) complete repainting; (c) complete repainting plus window treatments; (d) window

  10. Enzyme-linked immunosorbent assay for quantifying antigens of Dermatophagoides farinae and D. pteronyssinus (Acari: Pyroglyphidae) in house dust samples.

    PubMed

    Konishi, E; Uehara, K

    1990-11-01

    Double-antibody sandwich enzyme-linked immunosorbent assay (ELISA) using a monoclonal antibody as capture and detector antibodies was developed for quantifying antigens of Dermatophagoides farinae Hughes and D. pteronyssinus (Trouessart) mites contained in house dust samples. This monoclonal antibody was directed against mite antigens that were also reactive to immunoglobulin E antibody in all of 10 serum samples obtained from patients allergic to mites. Histological study using fluorescent antibody revealed that the monoclonal antibody was bound to the major part of the D. farinae mite body section including fecal matter and cuticles. The detection limit of the assay system was 0.17 microgram of soluble antigens of both mite species and the antigen amount corresponding to 0.5 mites per microplate well, whether in live or dead mites. This system did not react to antigens of Tyrophagus putrescentiae (Schrank) and Cheyletus malaccensis Oudemans. Slight inhibition of less than or equal to 21.3% was observed with nonspecific substances contained in house dust, such as wool, cotton, human dander, human hair, soil, and biscuit, but no direct ELISA reactions were obtained with any of these materials. In 49 house dust samples, ELISA was significantly correlated with the conventional microscopic observation method. PMID:2280398

  11. In vivo Clonal Dominance and Limited T-Cell Receptor Usage in Human CD4^+ T-Cell Recognition of House Dust Mite Allergens

    Microsoft Academic Search

    Lucy R. Wedderburn; Robyn E. O'Hehir; Colin R. A. Hewitt; Jonathan R. Lamb; Michael J. Owen

    1993-01-01

    Sensitivity to house dust mite antigens in atopic individuals is a major cause of allergic diseases, ranging from asthma to rhinitis and dermatitis. We have studied the T-cell receptor (TCR) usage of house-dust-mite-specific CD4^+ T-cell clones isolated from an atopic individual, by using the anchored polymerase chain reaction, and have analyzed the peripheral TCR repertoire of the same individual. Several

  12. Extraction and cleanup methods of dioxins in house dust from two cities in Japan using accelerated solvent extraction and a disposable multi-layer silica-gel cartridge

    Microsoft Academic Search

    Koichi Saito; Mikiko Takekuma; Masahiko Ogawa; Susumu Kobayashi; Yukio Sugawara; Masahiro Ishizuka; Hiroyuki Nakazawa; Yasuhiko Matsuki

    2003-01-01

    A simple and rapid method for the extraction and cleanup of dioxins from house dust was developed using an accelerated solvent extraction (ASE) method and a multi-layer silica-gel cartridge. It was found that the WHO-TEQ levels of dioxins extracted from the house dust obtained by both a conventional soxhlet extraction and the ASE were almost equal, when the data obtained

  13. Evaluation of Electrostatic Particle Ionization and BioCurtain Technologies to Reduce Dust, Odor and other Pollutants from Broiler Houses Final Report

    E-print Network

    Jerez, S.; Muhktar, S.; Faulkner, W.; Casey, K.; Borhan, S.; Hoff, A.; VanDelist, B.

    2011-01-01

    COLLEGE OF AGRICULTURE AND LIFE SCIENCES TR-415 2011 Evaluation of Electrostatic Particle Ionization and BioCurtain Technologies to Reduce Dust, Odor and other Pollutants from Broiler Houses Final Report Prepared for: Texas State Soil... of Electrostatic Particle Ionization and BioCurtain Technologies to Reduce Dust, Odor and other Pollutants from Broiler Houses Final Report Prepared for: Texas State Soil and Water Conservation Board By: Dr. Sheryll Jerez, Stephen F. Austin State...

  14. Molecular Basis of Arthropod Cross-Reactivity: IgE-Binding Cross-Reactive Epitopes of Shrimp, House Dust Mite and Cockroach Tropomyosins

    Microsoft Academic Search

    Rosalia Ayuso; Gerald Reese; Susan Leong-Kee; Matthew Plante; Samuel B. Lehrer

    2002-01-01

    Background: Shrimp may cross-react with other crustaceans and mollusks and nonedible arthropods such as insects (cockroach and chironomids), arachnids (house dust mites) and even nematodes. Since the muscle protein tropomyosin has been implicated as a possible cross-reacting allergen, this study characterized the IgE-binding epitopes in shrimp tropomyosin, Pen a 1, that cross-react with other allergenic invertebrate tropomyosins in house dust

  15. After the PBDE Phase-Out: A Broad Suite of Flame Retardants in Repeat House Dust Samples from California

    PubMed Central

    2012-01-01

    Higher house dust levels of PBDE flame retardants (FRs) have been reported in California than other parts of the world, due to the state’s furniture flammability standard. However, changing levels of these and other FRs have not been evaluated following the 2004 U.S. phase-out of PentaBDE and OctaBDE. We analyzed dust collected in 16 California homes in 2006 and again in 2011 for 62 FRs and organohalogens, which represents the broadest investigation of FRs in homes. Fifty-five compounds were detected in at least one sample; 41 in at least 50% of samples. Concentrations of chlorinated OPFRs, including two (TCEP and TDCIPP) listed as carcinogens under California’s Proposition 65, were found up to 0.01% in dust, higher than previously reported in the U.S. In 75% of the homes, we detected TDBPP, or brominated “Tris,” which was banned in children’s sleepwear because of carcinogenicity. To our knowledge, this is the first report on TDBPP in house dust. Concentrations of Firemaster 550 components (EH-TBB, BEH-TEBP, and TPHP) were higher in 2011 than 2006, consistent with its use as a PentaBDE replacement. Results highlight the evolving nature of FR exposures and suggest that manufacturers continue to use hazardous chemicals and replace chemicals of concern with chemicals with uncharacterized toxicity. PMID:23185960

  16. Environmental Exposures to Lead and Urban Children's Blood Lead Levels

    Microsoft Academic Search

    Bruce P. Lanphear; David A. Burgoon; Steven W. Rust; Shirley Eberly; Warren Galke

    1998-01-01

    Lead-contaminated water, soil, and paint have been recognized as potential sources of children's lead exposure for decades, but their contributions to lead intake among urban children remain poorly defined. This analysis was undertaken to estimate the relationship of environmental lead exposures to lead intake among a random sample of urban children, adjusted for exposure to lead-contaminated house dust. Analyses of

  17. Isomer Profiles of Perfluorochemicals in Matched Maternal, Cord, and House Dust Samples: Manufacturing Sources and Transplacental Transfer

    PubMed Central

    Beesoon, Sanjay; Webster, Glenys M.; Shoeib, Mahiba; Harner, Tom; Benskin, Jonathan P.

    2011-01-01

    Background: Perfluorochemicals (PFCs) are detectable in the general population and in the human environment, including house dust. Sources are not well characterized, but isomer patterns should enable differentiation of historical and contemporary manufacturing sources. Isomer-specific maternal–fetal transfer of PFCs has not been examined despite known developmental toxicity of perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) in rodents. Objectives: We elucidated relative contributions of electrochemical (phased out in 2001) and telomer (contemporary) PFCs in dust and measured how transplacental transfer efficiency (TTE; based on a comparison of maternal and cord sera concentrations) is affected by perfluorinated chain length and isomer branching pattern. Methods: We analyzed matching samples of house dust (n = 18), maternal sera (n = 20), and umbilical cord sera (n = 20) by isomer-specific high-performance liquid chromatography tandem mass spectrometry. Results: PFOA isomer signatures revealed that telomer sources accounted for 0–95% of total PFOA in house dust (median, 31%). This may partly explain why serum PFOA concentrations are not declining in some countries despite the phase-out of electrochemical PFOA. TTE data indicate that total branched isomers crossed the placenta more efficiently than did linear isomers for both PFOS (p < 0.01) and PFOA (p = 0.02) and that placental transfer of branched isomers of PFOS increased as the branching point moved closer to the sulfonate (SO3–) end of the molecule. Conclusions: Results suggest that humans are exposed to telomer PFOA, but larger studies that also account for dietary sources should be conducted. The exposure profile of PFOS and PFOA isomers can differ between the mother and fetus—an important consideration for perinatal epidemiology studies of PFCs. PMID:21757419

  18. Sensitivity to Five Types of House Dust Mite in a Group of Allergic Egyptian Children

    PubMed Central

    El-Sayed, Shereen; Abdul-Rahman, Nahla

    2014-01-01

    Background: The published data on house dust mite (HDM) sensitization from Egypt are scanty. We sought to investigate the sensitization to five different types of HDM among a group of allergic children in a trial to outline the most frequent sensitizing strains in the Cairo Province. Methods: We consecutively enrolled 100 asthmatic patients, aged 1–7 years, of whom 22 had concomitant skin allergy. Skin prick testing was performed using allergen extracts of Dermatophagoides pteronyssinus, Dermatophagoides farinae, Lepidoglyphus destructor, Tyrophagus putrescentiae, and Acarus siro. Results: Twenty-four patients (24%) were sensitized to one or more strains of HDM. Sensitization to one strain was revealed in 12% of the studied sample, while sensitization to two or three strains was detected in 8% and 4% respectively. Twelve percent of the enrolled children were sensitive to D. pteronyssinus, 11% to D. farinae, 7% to L. destructor, 6% to T. putrescentiae, and 4% to A. siro. Eight out of the 12 (66%) children sensitive to one strain had mild intermittent asthma, while five out of eight (62.5%) sensitive to two strains had moderate persistent asthma. All children sensitized to three strains of HDM had persistent rather than intermittent asthma. HDM sensitization did not correlate significantly to the history of sun exposure, bed mattresses and pillows, living in farms, or exposure to stored grains. The co-existence of atopic dermatitis tended to have a higher rate of HDM sensitization. Conclusion: D. pteronyssinus and D. farinae represent the most common sensitizing strains in the studied sample. Wider-scale population-based studies are needed to assess the prevalence of HDM allergy and its clinical correlates in our country. PMID:25276487

  19. Paradoxical Effects of Rapamycin on Experimental House Dust Mite-Induced Asthma

    PubMed Central

    Fredriksson, Karin; Yao, Xianglan; Meyer, Katharine S.; Keeran, Karen J.; Zywicke, Gayle J.; Qu, Xuan; Yu, Zu-Xi; Moss, Joel; Kristof, Arnold S.; Levine, Stewart J.

    2012-01-01

    The mammalian target of rapamycin (mTOR) modulates immune responses and cellular proliferation. The objective of this study was to assess whether inhibition of mTOR with rapamycin modifies disease severity in two experimental murine models of house dust mite (HDM)-induced asthma. In an induction model, rapamycin was administered to BALB/c mice coincident with nasal HDM challenges for 3 weeks. In a treatment model, nasal HDM challenges were performed for 6 weeks and rapamycin treatment was administered during weeks 4 through 6. In the induction model, rapamycin significantly attenuated airway inflammation, airway hyperreactivity (AHR) and goblet cell hyperplasia. In contrast, treatment of established HDM-induced asthma with rapamycin exacerbated AHR and airway inflammation, whereas goblet cell hyperplasia was not modified. Phosphorylation of the S6 ribosomal protein, which is downstream of mTORC1, was increased after 3 weeks, but not 6 weeks of HDM-challenge. Rapamycin reduced S6 phosphorylation in HDM-challenged mice in both the induction and treatment models. Thus, the paradoxical effects of rapamycin on asthma severity paralleled the activation of mTOR signaling. Lastly, mediastinal lymph node re-stimulation experiments showed that treatment of rapamycin-naive T cells with ex vivo rapamycin decreased antigen-specific Th2 cytokine production, whereas prior exposure to in vivo rapamycin rendered T cells refractory to the suppressive effects of ex vivo rapamycin. We conclude that rapamycin had paradoxical effects on the pathogenesis of experimental HDM-induced asthma. Thus, consistent with the context-dependent effects of rapamycin on inflammation, the timing of mTOR inhibition may be an important determinant of efficacy and toxicity in HDM-induced asthma. PMID:22685525

  20. The Effects of Storage Conditions on the Stability of House Dust Mite Extracts

    PubMed Central

    Jeong, Kyoung Yong; Choi, Soo-Young; Han, In-Soo; Lee, Jae-Hyun; Lee, Joo-Shil; Hong, Chein-Soo

    2013-01-01

    Purpose Allergen extracts from the house dust mite (HDM, Dermatophagoides pteronyssinus) are widely utilized for diagnosis and treatment of allergic diseases. It is known that allergen extracts degrade and lose potency when stored over time. Methods This study aimed to determine the optimal conditions for stability of allergen extracts. This study was undertaken to investigate the optimal storage conditions for HDM extracts, the effects of adding 0.03% human serum albumin (HSA) and 50% glycerol were evaluated at -20?, 4?, and room temperature (RT). Changes in protein and group 1 major allergen (Der p 1) concentration, as well as allergenicity were measured over a 1 year period using the Bradford assay, two-site ELISA, and ELISA inhibition. Results Protein concentrations decreased by 86%, 51%, and 6% at RT, 4?, and -20?, respectively, when stored in distilled water. Overall allergenicity remained high (89.9%) when the extracts was reconstituted in 50% glycerol solution, and was 93.1% when reconstituted in 50% glycerol and 0.03% HSA at RT. Allergenicity was decreased to 36.6% and 33.3%, however, reconstitution in DW or 0.03% HSA solution at RT, respectively. Allergenicity was remained high as 92.0%-97.0% when stored at 4? regardless of the buffer conditions. Conclusions Storage temperature is the most important factor in preserving allergenicity of HDM extracts, which is ideal at 4?. The addition of 50% glycerol to the storage buffer was also found to play an important role in increasing the shelf-life of HDM extracts at RT. PMID:24179687

  1. Epigenetic alterations by DNA methylation in house dust mite-induced airway hyperresponsiveness.

    PubMed

    Shang, Yan; Das, Sandhya; Rabold, Richard; Sham, James S K; Mitzner, Wayne; Tang, Wan-yee

    2013-08-01

    Asthma is one of the most prevalent chronic lung diseases, affecting 235 million individuals around the world, with its related morbidity and mortality increasing steadily over the last 20 years. Exposure to the environmental allergen, house dust mite (HDM), results in airway inflammation with a variable degree of airway obstruction. Although there has been much experimental work in the past using HDM challenge models to understand mechanistic details in allergic inflammation and airway hyperresponsiveness (AHR), there has been no study on reprogramming of lung or airways mediated through epigenetic mechanisms in response to an acute HDM exposure. Male mice, 6 weeks of age, were administrated HDM extracts or saline at Days 1, 14, and 21. Exposure of mice to HDM extracts caused significant airway inflammation and increased AHR. These HDM-challenged mice also exhibited a change in global DNA methylation as compared with saline-exposed (control) mice. Next, by employing methylation-sensitive restriction fingerprinting, we identified a set of genes, showing aberrant methylation status, associated with the HDM-induced AHR. These candidate genes are known to be involved in cAMP signaling (pde4 d), Akt-signaling (akt1 s1), ion transport (tm6 sf1, pom121l2, and slc8a3), and fatty acid metabolism (acsl3). Slc8a3 and acsl3 were down-regulated, whereas pde4 d, akt1 s1, tm6 sf1, and pom121l2 were up-regulated in the mice exposed to HDM. Hence, our results suggest that HDM exposure induces a series of aberrant methylated genes that are potentially important for the development of allergic AHR. PMID:23526225

  2. Gene Expression in the Skin of Dogs Sensitized to the House Dust Mite Dermatophagoides farinae

    PubMed Central

    Schamber, Paz; Schwab-Richards, Rachel; Bauersachs, Stefan; Mueller, Ralf S.

    2014-01-01

    Atopic dermatitis is a multifactorial allergic skin disease in humans and dogs. Genetic predisposition, immunologic hyperreactivity, a defective skin barrier, and environmental factors play a role in its pathogenesis. The aim of this study was to analyze gene expression in the skin of dogs sensitized to house dust mite antigens. Skin biopsy samples were collected from six sensitized and six nonsensitized Beagle dogs before and 6 hr and 24 hr after challenge using skin patches with allergen or saline as a negative control. Transcriptome analysis was performed by the use of DNA microarrays and expression of selected genes was validated by quantitative real-time RT-PCR. Expression data were compared between groups (unpaired design). After 24 hr, 597 differentially expressed genes were detected, 361 with higher and 226 with lower mRNA concentrations in allergen-treated skin of sensitized dogs compared with their saline-treated skin and compared with the control specimens. Functional annotation clustering and pathway- and co-citation analysis showed that the genes with increased expression were involved in inflammation, wound healing, and immune response. In contrast, genes with decreased expression in sensitized dogs were associated with differentiation and barrier function of the skin. Because the sensitized dogs did not show differences in the untreated skin compared with controls, inflammation after allergen patch test probably led to a decrease in the expression of genes important for barrier formation. Our results further confirm the similar pathophysiology of human and canine atopic dermatitis and revealed genes previously not known to be involved in canine atopic dermatitis. PMID:25098772

  3. Dust detector using piezoelectric lead zirconate titanate with current-to-voltage converting amplifier for functional advancement

    NASA Astrophysics Data System (ADS)

    Kobayashi, Masanori; Miyachi, Takashi; Hattori, Maki; Sugita, Seiji; Takechi, Seiji; Okada, Nagaya

    2013-03-01

    This paper describes the concept of a dust monitor using lead zirconate titanate (PZT) ceramics with a large detection area. Its potential as a dust detector is experimentally demonstrated. The dust monitor has a small volume compared to an impact ionization detector with the same detection area, due to the PZT sensor. The PZT sensor, as a traditional device for the in-situ observation of hypervelocity dust particles, has been used for momentum measurement. The hypervelocity impact signals of PZT sensors are typically read by charge-sensitive amplifiers. Instead, we suggest a new method that a current-to-voltage converting amplifier is useful for interpreting the impact signal of a PZT sensor arising from dust particles down to 0.5 ?m in radius. We propose that datasets of dust impacts can be obtained with a higher statistical accuracy, if the new method is applied to instruments on forthcoming interplanetary-space-cruising spacecrafts.

  4. A new exposure metric for traffic-related air pollution? An analysis of determinants of hopanes in settled indoor house dust

    PubMed Central

    2013-01-01

    Background Exposure to traffic-related air pollution (TRAP) can adversely impact health but epidemiologic studies are limited in their abilities to assess long-term exposures and incorporate variability in indoor pollutant infiltration. Methods In order to examine settled house dust levels of hopanes, engine lubricating oil byproducts found in vehicle exhaust, as a novel TRAP exposure measure, dust samples were collected from 171 homes in five Canadian cities and analyzed by gas chromatography–mass spectrometry. To evaluate source contributions, the relative abundance of the highest concentration hopane monomer in house dust was compared to that in outdoor air. Geographic variables related to TRAP emissions and outdoor NO2 concentrations from city-specific TRAP land use regression (LUR) models were calculated at each georeferenced residence location and assessed as predictors of variability in dust hopanes. Results Hopanes relative abundance in house dust and ambient air were significantly correlated (Pearson’s r=0.48, p<0.05), suggesting that dust hopanes likely result from traffic emissions. The proportion of variance in dust hopanes concentrations explained by LUR NO2 was less than 10% in Vancouver, Winnipeg and Toronto while the correlations in Edmonton and Windsor explained 20 to 40% of the variance. Modeling with household factors such as air conditioning and shoe removal along with geographic predictors related to TRAP generally increased the proportion of explained variability (10-80%) in measured indoor hopanes dust levels. Conclusions Hopanes can consistently be detected in house dust and may be a useful tracer of TRAP exposure if determinants of their spatiotemporal variability are well-characterized, and when home-specific factors are considered. PMID:23782977

  5. A side-by-side comparison of three allergen sampling methods in settled house dust.

    PubMed

    Sandel, Megan; Murphy, Johnna S; Dixon, Sherry L; Adgate, John L; Chew, Ginger L; Dorevitch, Samuel; Jacobs, David E

    2014-11-01

    Understanding allergen exposure and potential relationships with asthma requires allergen sampling methods, but methods have yet to be standardized. We compared allergen measurements from dust collected from 200 households with asthmatics and conducted a side-by-side vacuum sampling of settled dust in each home's kitchen, living room and subject's bedroom by three methods (EMM, HVS4 and AIHA). Each sample was analyzed for dust mite, cockroach, mouse, rat, cat and dog allergens. The number of samples with sufficient dust mass for allergen analysis was significantly higher for Eureka Mighty Mite (EMM) and high volume small surface sampler (HVS4) compared with American Industrial Hygiene Association (AIHA) in all rooms and surfaces tested (all P<0.05). The allergen concentration (weight of allergen divided by total weight of dust sampled) measured by the EMM and HVS4 methods was higher than that measured by the AIHA. Allergen loadings (weight of allergen divided by surface area sampled) were significantly higher for HVS4 than for AIHA and EMM. Cockroach and rat allergens were rarely detected via any method. The EMM method is most likely to collect sufficient dust from surfaces in the home and is relatively practical and easy. The AIHA and HVS4 methods suffer from insufficient dust collection and/or difficulty in use. PMID:24802556

  6. Metals and metalloids in atmospheric dust: Use of lead isotopic analysis for source apportionment

    NASA Astrophysics Data System (ADS)

    Felix Villar, Omar I.

    Mining activities generate aerosol in a wide range of sizes. Smelting activities produce mainly fine particles (<1 microm). On the other hand, milling, crushing and refining processes, as well tailings management, are significant sources of coarse particles (> 1 microm). The adverse effects of aerosols on human health depend mainly on two key characteristics: size and chemical composition. One of the main objectives of this research is to analyze the size distribution of contaminants in aerosol produced by mining operations. For this purpose, a Micro-Orifice Uniform Deposit Impactor (MOUDI) was utilized. Results from the MOUDI samples show higher concentrations of the toxic elements like lead and arsenic in the fine fraction (<1 microm). Fine particles are more likely to be deposited in the deeper zones of the respiratory system; therefore, they are more dangerous than coarse particles that can be filtered out in the upper respiratory system. Unfortunately, knowing the total concentration of contaminants does not give us enough information to identify the source of contamination. For this reason, lead isotopes have been introduced as fingerprints for source apportionment. Each source of lead has specific isotopic ratios; by knowing these ratios sources can be identified. During this research, lead isotopic ratios were analyzed at different sites and for different aerosol sizes. From these analyses it can be concluded that lead isotopes are a powerful tool to identify sources of lead. Mitigation strategies could be developed if the source of contamination is well defined. Environmental conditions as wind speed, wind direction, relative humidity and precipitation have an important role in the concentration of atmospheric dust. Dry environments with low relative humidity are ideal for the transport of aerosols. Results obtained from this research show the relationship between dust concentrations and meteorological parameters. Dust concentrations are highly correlated with relative humidity and wind speed. With all the data collected on site and the analysis of the meteorological parameters, models can be develop to predict the transport of particles as well as the concentration of contaminants at a specific point. These models were developed and are part of the results shown in this dissertation.

  7. Environmental arsenic, cadmium and lead dust emissions from metal mine operations: Implications for environmental management, monitoring and human health.

    PubMed

    Taylor, Mark Patrick; Mould, Simon Anthony; Kristensen, Louise Jane; Rouillon, Marek

    2014-11-01

    Although blood lead values in children are predominantly falling globally, there are locations where lead exposure remains a persistent problem. One such location is Broken Hill, Australia, where the percentage of blood lead values >10 ?g/dL in children aged 1-4 years has risen from 12.6% (2010), to 13% (2011) to 21% (2012). The purpose of this study was to determine the extent of metal contamination in places accessible to children. This study examines contemporary exposure risks from arsenic, cadmium, lead, silver and zinc in surface soil and dust, and in pre- and post-play hand wipes at six playgrounds across Broken Hill over a 5-day period in September 2013. Soil lead (mean 2,450 mg/kg) and zinc (mean 3,710 mg/kg) were the most elevated metals in playgrounds. Surface dust lead concentrations were consistently elevated (mean 27,500 ?g/m(2)) with the highest lead in surface dust (59,900 ?g/m(2)) and post-play hand wipes (60,900 ?g/m(2)) recorded close to existing mining operations. Surface and post-play hand wipe dust values exceeded national guidelines for lead and international benchmarks for arsenic, cadmium and lead. Lead isotopic compositions ((206)Pb/(207)Pb, (208)Pb/(207)Pb) of surface dust wipes from the playgrounds revealed the source of lead contamination to be indistinct from the local Broken Hill ore body. The data suggest frequent, cumulative and ongoing mine-derived dust metal contamination poses a serious risk of harm to children. PMID:25462679

  8. Gene-by-environment effect of house dust mite on purinergic receptor P2Y12 (P2RY12) and lung function in children with asthma

    PubMed Central

    Bunyavanich, Supinda; Boyce, Joshua A.; Raby, Benjamin A.; Weiss, Scott T.

    2012-01-01

    Background Distinct receptors likely exist for leukotriene(LT)E4, a potent mediator of airway inflammation. Purinergic receptor P2Y12 is needed for LTE4-induced airways inflammation, and P2Y12 antagonism attenuates house dust mite-induced pulmonary eosinophilia in mice. Although experimental data support a role for P2Y12 in airway inflammation, its role in human asthma has never been studied. Objective To test for association between variants in the P2Y12 gene (P2RY12) and lung function in human subjects with asthma, and to examine for gene-by-environment interaction with house dust mite exposure. Methods 19 single nucleotide polymorphisms (SNPs) in P2RY12 were genotyped in 422 children with asthma and their parents (n=1266). Using family-based methods, we tested for associations between these SNPs and five lung function measures. We performed haplotype association analyses and tested for gene-by-environment interactions using house dust mite exposure. We used the false discovery rate to account for multiple comparisons. Results Five SNPs in P2RY12 were associated with multiple lung function measures (P values 0.006–0.025). Haplotypes in P2RY12 were also associated with lung function (P values 0.0055–0.046). House dust mite exposure modulated associations between P2RY12 and lung function, with minor allele homozygotes exposed to house dust mite demonstrating worse lung function than those unexposed (significant interaction P values 0.0028–0.040). Conclusions and clinical relevance P2RY12 variants were associated with lung function in a large family-based asthma cohort. House dust mite exposure caused significant gene-by-environment effects. Our findings add the first human evidence to experimental data supporting a role for P2Y12 in lung function. P2Y12 could represent a novel target for asthma treatment. PMID:22010907

  9. Organophosphorous pesticide breakdown products in house dust and children’s urine

    PubMed Central

    Quirós-Alcalá, Lesliam; Bradman, Asa; Smith, Kimberly; Weerasekera, Gayanga; Odetokun, Martins; Barr, Dana Boyd; Nishioka, Marcia; Castorina, Rosemary; Hubbard, Alan E.; Nicas, Mark; Hammond, S. Katharine; McKone, Thomas E.; Eskenazi, Brenda

    2014-01-01

    Human exposure to preformed dialkylphosphates (DAPs) in food or the environment may affect the reliability of DAP urinary metabolites as biomarkers of organophosphate (OP) pesticide exposure. We conducted a study to investigate the presence of DAPs in indoor residential environments and their association with children’s urinary DAP levels. We collected dust samples from homes in farmworker and urban communities (40 homes total, n = 79 samples) and up to two urine samples from resident children ages 3–6 years. We measured six DAPs in all samples and eight DAP-devolving OP pesticides in a subset of dust samples (n = 54). DAPs were detected in dust with diethylphosphate (DEP) being the most frequently detected (?60%); detection frequencies for other DAPs were ?50%. DEP dust concentrations did not significantly differ between communities, nor were concentrations significantly correlated with concentrations of chlorpyrifos and diazinon, the most frequently detected diethyl-OP pesticides (Spearman ? = ?0.41 to 0.38, P>0.05). Detection of DEP, chlorpyrifos, or diazinon, was not associated with DEP and/or DEP + diethylthiophosphate detection in urine (Kappa coefficients = ?0.33 to 0.16). Finally, estimated non-dietary ingestion intake from DEP in dust was found to be ?5% of the dose calculated from DEP levels in urine, suggesting that ingestion of dust is not a significant source of DAPs in urine if they are excreted unchanged. PMID:22781438

  10. Evaluation of dust exposure to truck drivers following the lead haul truck

    Microsoft Academic Search

    W. R. Reed; J. A. Organiscak

    Haul trucks have the potential to generate large amounts of respirable dust. This respirable dust has been shown to be a health hazard to personnel, especially if it has a high silica content. Lack of dust sampling data from haul trucks prompted the completion of a study to quantify respirable dust concentrations. These field studies were conducted measuring instantaneous respirable

  11. [Effectiveness of a test for verification of the presence of acari in house dust for the prevention of respiratory allergies in children].

    PubMed

    Cantani, A; Arcese, G; Serra, A; Lucenti, P

    1995-01-01

    Respiratory allergy and bronchial asthma in particular can be serious afflictions in younger as well as in older children. Therefore interest has been focused on methods for the prevention of atopy. The role and allergenic importance of Dermatophagoides pteronyssinus (Dpt) in house and other environments have been identified. This mite provokes asthma in children at an earlier age than pollens. However the most under-valued area of asthma prevention is environmental control. The steps may seem difficult at first, but the results will be well worth the efforts and the sacrifices. We report on the high effectiveness of the guanine detection test (Acarex) based on the colorimetric quantification of allergen sources in house dust (mattresses, pillows, upholstered furniture, carpets, moquettes, etc), which can be treated with house dust mite extermination products such as benzyl benzoate. The eradication measures will allow the parents to reduce the allergen exposure, to be monitored at 3-6 month intervals. The guanine detection test performed in our Division on house dust samples assembled by the patents of children with house dust mite induced asthma (study group) or pollen asthma (control group) yielded highly significant statistical differences. PMID:8545553

  12. 24 CFR 1000.40 - Do lead-based paint poisoning prevention requirements apply to affordable housing activities...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 false Do lead-based paint poisoning prevention requirements apply...General § 1000.40 Do lead-based paint poisoning prevention requirements apply...activities under NAHASDA? Yes, lead-based paint requirements apply to housing...

  13. 24 CFR 1000.40 - Do lead-based paint poisoning prevention requirements apply to affordable housing activities...

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 false Do lead-based paint poisoning prevention requirements apply...General § 1000.40 Do lead-based paint poisoning prevention requirements apply...activities under NAHASDA? Yes, lead-based paint requirements apply to housing...

  14. 24 CFR 1000.40 - Do lead-based paint poisoning prevention requirements apply to affordable housing activities...

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 false Do lead-based paint poisoning prevention requirements apply...General § 1000.40 Do lead-based paint poisoning prevention requirements apply...activities under NAHASDA? Yes, lead-based paint requirements apply to housing...

  15. 24 CFR 1000.40 - Do lead-based paint poisoning prevention requirements apply to affordable housing activities...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 false Do lead-based paint poisoning prevention requirements apply...General § 1000.40 Do lead-based paint poisoning prevention requirements apply...activities under NAHASDA? Yes, lead-based paint requirements apply to housing...

  16. 24 CFR 1000.40 - Do lead-based paint poisoning prevention requirements apply to affordable housing activities...

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 false Do lead-based paint poisoning prevention requirements apply...General § 1000.40 Do lead-based paint poisoning prevention requirements apply...activities under NAHASDA? Yes, lead-based paint requirements apply to housing...

  17. 76 FR 12106 - Lead-Based Paint Renovation, Repair and Painting Activities in Target Housing and Child Occupied...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-04

    ...EPA-R07-OW-2011-0112; FRL-9275-5] Lead-Based Paint Renovation, Repair and Painting Activities...statute was the Residential Lead-Based Paint Hazard Reduction Act of 1992. That Act...administered regulations concerning lead- based paint in housing since 2000. The U.S....

  18. Levels of non-polybrominated diphenyl ether brominated flame retardants in residential house dust samples and fire station dust samples in California.

    PubMed

    Brown, F Reber; Whitehead, Todd P; Park, June-Soo; Metayer, Catherine; Petreas, Myrto X

    2014-11-01

    Eleven novel brominated flame retardants (NBFRs) were analyzed in dust samples from California homes as a part of the Northern California Childhood Leukemia Study (NCCLS) and from the living quarters of California fire stations as a part of the Firefighter Occupational Exposure (FOX) study using high resolution gas chromatography/mass spectrometry. The eleven NBFRs were ?- and ?-1,2-dibromo-4-(1,2-dibromoethyl)cyclohexane (?- and ?-DBE-DBCH), 2-bromoallyl 2,3,6-tribromophenylether (BATE), pentabromotoluene (PBT), pentabromoethylbenzene (PBEB), 2,3-dibromopropyl 2,4,6-tribromophenyl ether (TBP-DBPE), hexabromobenzene (HBB), 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EH-TBB), 1,2-bis(2,4,6-tribromophenoxy) ethane (BTBPE), bis(2-ethylhexyl) tetrabromophthalate (BEH-TEBP), and decabromodiphenylethane (DBDPE). Six of the seven NBFRs that are produced in relatively small quantities (i.e., ?-, ?-DBE-DBCH, BATE, PBEB, PBT, TBP-DBPE) were measured close to or below the limit of quantitation (0.64 ng/g) in both the NCCLS and FOX samples, and the seventh, HBB, was measured at median concentrations of 1.85 ng/g and 9.40 ng/g in the NCCLS and FOX samples, respectively. The remaining four NBFRs, EH-TBB, BEH-TEBP, BTBPE, and DBDPE, are produced in higher quantities, and were detected at median concentrations of 337 ng/g, 186 ng/g, 22.3 ng/g, and 82.8 ng/g, respectively in the NCCLS samples, and at median concentrations of 2687 ng/g, 2076 ng/g, 28.4 ng/g, and 161 ng/g, respectively, in the FOX samples. Concentrations of NBFRs in the NCCLS and FOX dust samples were several times lower than concentrations of PBDEs previously measured in the same samples. Concentrations of NBFRs in the NCCLS and FOX dust samples were generally comparable to concentrations of NBFRs in other studies of house dust from the US and Canada. PMID:25261858

  19. Evaluation of errors and limits of the 63-?m house-dust-fraction method, a surrogate to predict hidden moisture damage

    PubMed Central

    Baudisch, Christoph; Assadian, Ojan; Kramer, Axel

    2009-01-01

    Background The aim of this study is to analyze possible random and systematic measurement errors and to detect methodological limits of the previously established method. Findings To examine the distribution of random errors (repeatability standard deviation) of the detection procedure, collective samples were taken from two uncontaminated rooms using a sampling vacuum cleaner, and 10 sub-samples each were examined with 3 parallel cultivation plates (DG18). In this two collective samples of new dust, the total counts of Aspergillus spp. varied moderately by 25 and 29% (both 9 cfu per plate). At an average of 28 cfu/plate, the total number varied only by 13%. For the evaluation of the influence of old dust, old and fresh dust samples were examined. In both cases with old dust, the old dust influenced the results indicating false positive results, where hidden moist was indicated but was not present. To quantify the influence of sand and sieving, 13 sites were sampled in parallel using the 63-?m- and total dust collection approaches. Sieving to 63-?m resulted in a more then 10-fold enrichment, due to the different quantity of inert sand in each total dust sample. Conclusion The major errors during the quantitative evaluation from house dust samples for mould fungi as reference values for assessment resulted from missing filtration, contamination with old dust and the massive influence of soil. If the assessment is guided by indicator genera, the percentage standard deviation lies in a moderate range. PMID:19852825

  20. Pyrethroids in house dust from the homes of farm worker families in the MICASA study

    E-print Network

    Hammock, Bruce D.

    of the pyrethroids cis- and trans-permethrin, cypermethrin, deltamethrin, esfenvalerate and resmethrin in single dust samples collected from 55 households. Cis- and trans-permethrin had the highest detection frequencies frequencies and/or lower median concentrations of cis- and trans-permethrin and cypermethrin were observed

  1. QUANTITATIVE PCR ANALYSIS OF HOUSE DUST CAN REVEAL ABNORMAL MOLD CONDITIONS

    EPA Science Inventory

    Indoor mold populations were measured in the dust of homes in Cleveland and Cincinnati, OH, by quantitative PCR (QPCR) and, in Cincinnati, also by culturing. QPCR assays for 82 species (or groups of species) were used to identify and quantify indoor mold populations in moldy home...

  2. Quantification of Ergosterol and 3Hydroxy Fatty Acids in Settled House Dust by Gas Chromatography-Mass Spectrometry: Comparison with Fungal Culture and Determination of Endotoxin by a Limulus Amebocyte Lysate Assay

    Microsoft Academic Search

    ANITA SARAF; LENNART LARSSON; HARRIET BURGE; DONALD MILTON

    Ergosterol and 3-hydroxy fatty acids, chemical markers for fungal biomass and the endotoxin of gram- negative bacteria, respectively, may be useful in studies of health effects of organic dusts, including domestic house dust. This paper reports a method for the combined determination of ergosterol and 3-hydroxy fatty acids in a single dust sample and a comparison of these chemical biomarkers

  3. Eighteen-month outcomes of house dust mite avoidance and dietary fatty acid modification in the childhood asthma prevention study (CAPS)

    Microsoft Academic Search

    Seema Mihrshahi; Jennifer K. Peat; Guy B. Marks; Craig M. Mellis; Euan R. Tovey; Karen Webb; Warwick J. Britton; Stephen R. Leeder

    2003-01-01

    Background: Observational studies have linked house dust mite (HDM) exposure and dietary fatty acid intake with asthma in childhood. However, definitive evidence of their role in the etiology of asthma requires a randomized controlled trial. Objective: We hypothesized that the incidence of asthma and allergy in high-risk children would be reduced by avoidance of HDM allergens, supplementation with omega-3 fatty

  4. Observational Study of the Safety of an Ultra-Rush Sublingual Immunotherapy Regimen to Treat Rhinitis due to House Dust Mites

    Microsoft Academic Search

    Albert Roger; José-Luis Justicia; Luis Ángel Navarro; José Luis Eseverri; Jeroni Ferrčs; Alfons Malet; Víctor Alvŕ

    2011-01-01

    Background: Ultra-rush regimens for administering sublingual immunotherapy to patients with allergies are becoming more widespread. We aimed to assess treatment safety for patients with allergic rhinitis with or without asthma caused by Dermatophagoides house dust mites. Methods: This observational study at 5 Spanish centers included 218 patients aged 4–64 years, of whom 117 were women and 122 were under 15

  5. Randomized double-blind placebo-controlled trial of sublingual immunotherapy in children with house dust mite allergy in primary care: study design and recruitment

    Microsoft Academic Search

    Cindy MA de Bot; Heleen Moed; Marjolein Y Berger; Esther Röder; Hans de Groot; Johan C de Jongste; Roy Gerth van Wijk; Johannes C van der Wouden

    2008-01-01

    BACKGROUND: For respiratory allergic disorders in children, sublingual immunotherapy has been developed as an alternative to subcutaneous immunotherapy. Sublingual immunotherapy is more convenient, has a good safety profile and might be an attractive option for use in primary care. A randomized double-blind placebo-controlled study was designed to establish the efficacy of sublingual immunotherapy with house dust mite allergen compared to

  6. Fungal extracellular polysaccharides in house dust as a marker for exposure to fungi: Relations with culturable fungi, reported home dampness, and respiratory symptoms

    Microsoft Academic Search

    Jeroen Douwes; Betty van der Sluis; Gert Doekes; Frans van Leusden; Luc Wijnands; Rob van Strien; Arnoud Verhoeff; Bert Brunekreef

    1999-01-01

    Background: Epidemiologic studies have demonstrated an association between indoor fungal growth and respiratory symptoms. However, in only a few studies was fungal exposure actually measured. Objective: The purpose of this study was to evaluate the measurement by enzyme immunoassay of extracellular polysaccharides of Aspergillus and Penicillium species (EPS-Asp\\/Pen ) in house dust as a marker for fungal exposure and to

  7. Nitric oxide production by alveolar macrophages in response to house dust mite fecal pellets and the mite allergens, Der p 1 and Der p 2

    Microsoft Academic Search

    Helen L. Peake; Andrew J. Currie; Geoffrey A. Stewart; Andrew S. McWilliam

    2003-01-01

    BackgroundAllergens are frequently found within or attached to particulate material. For example, house dust mite fecal pellets (HDMFP) contain the major mite allergens, exposure to which have been implicated in the development of asthma. Although several studies have examined the ability of purified allergens to generate inflammatory responses, few studies have investigated whether HDMFP per se, are biologically active.

  8. Identification, characterization, and cloning of a complementary DNA encoding a 60-kd house dust mite allergen (Der f 18) for human beings and dogs

    Microsoft Academic Search

    Eric Weber; Shirley Hunter; Kim Stedman; Steve Dreitz; Thierry Olivry; Andrew Hillier; Catherine McCall

    2003-01-01

    Background: House dust mites of the Dermatophagoides genus are the most important cause of perennial allergic disease in both humans and companion animals. Although the major mite allergens for humans are proteins of relatively low molecular weight, this is not the case for dogs. Western blotting shows that canine anti-mite IgE responses are directed primarily toward proteins in the molecular

  9. High-Level Expression in Mammalian Cells of Recombinant House Dust Mite Allergen ProDer p 1 with Optimized Codon Usage

    Microsoft Academic Search

    Marc Massaer; Pasqualina Mazzu; Michčle Haumont; Mauro Magi; Véronique Daminet; Alex Bollen; Alain Jacquet

    2001-01-01

    Background: The major house dust mite allergen Der p 1 is associated with allergic diseases such as asthma. Production of recombinant Der p 1 was previously attempted, but with limited success. The present study describes the expression of recombinant (rec) ProDer p 1, a recombinant precursor form of Der p 1, in CHO cells. Methods: As optimization of the codon

  10. Antibody and cytokine responses to house dust mite allergens and Toxoplasma gondii antigens in atopic and non-atopic Brazilian subjects

    Microsoft Academic Search

    Jorge F. C. Fernandes; Ernesto A. Taketomi; Jose R. Mineo; Diego O. Miranda; Ronaldo Alves; Rafael O. Resende; Leandro H. Ynoue; Sun-Sang J. Sung; Deise A. O. Silva

    2010-01-01

    According to hygiene hypothesis, a lower exposure to infection is associated with increased prevalence of allergic diseases. This study aimed to investigate the association between atopy and Toxoplasma gondii (Tg) infection by analyzing the antibody and cytokine responses to house dust mite allergens and T. gondii antigens in Brazilian subjects. A total of 275 individuals were assessed and divided into

  11. Cloning and characterization of a new allergen, Mag 3, from the house dust mite, Dermatophagoides farinae: Cross-reactivity with high-molecular-weight allergen

    Microsoft Academic Search

    Akihiro Fujikawa; Noriyuki Ishimaru; Atsuko Seto; Hiroyuki Yamada; Tsunehiro Aki; Seiko Shigeta; Takeshi Wada; Toshihiko Jyo; Yoshikatu Murooka; Satoru Oka; Kazuhisa Ono

    1996-01-01

    A new immunoreactive clone whose sequence is not homologous to that of any of the previously identified mite allergens was isolated by successive immunoscreening of a Dermatophagoides farinae cDNA library with rabbit antisera to an extract of the house dust mite and IgE in pooled sera from patients allergic to mites. Rabbit antibodies specific for the recombinant protein recognized a

  12. Inhibition of T Cell and Antibody Responses to House Dust Mite Allergen by Inhalation of the Dominant T Cell Epitope in Naive and Sensitized Mice

    Microsoft Academic Search

    Gerard F. Hoyne; Robyn E. O'Hehir; David C. Wraith; Wayne R. Thomas; Jonathan R. Lamb

    Summary Antigen-specific CD4 + T cells play an important role in the allergic immune response to house dust mite (HDM) allergens in humans. The group 1 allergen ofDermatophagoides spp. is a major target antigen in both B and T cell recognition of HDM. In vitro studies have shown that the presentation of peptides to human T cells under appropriate conditions

  13. Penetration of light into carpet, and responses of the European house-dust mite ( Dermatophagoides pteronyssinus ) to varying light intensity and diurnal cycle

    Microsoft Academic Search

    Simon Causer; Caroline Shorter

    2004-01-01

    This study examined the question of what effect exposure to light might play in determining the vertical distribution of house-dust mites in carpet, and the degree to which light penetrates worn and unworn carpets of different pile conformation (loop- versus cut-pile), height and colour. The effect on population increase of a diurnal lighting cycle versus continual darkness was also investigated.

  14. Evidence for a Th2-to-Th1 shift in IL4 deficient mice in response to chronic house dust mite exposure

    Microsoft Academic Search

    J. R. Johnson; F. K. Swirski; R. Fattouh; M. D. Inman; M. Jordana

    2004-01-01

    RationaleIL-4 is an important mediator in the development of Th2-type inflammation in the airway. We therefore examined the response of IL-4 deficient (4KO) mice to chronic house dust mite (HDM) exposure, a protocol that results in a Th2-skewed response in wild type (WT) mice.

  15. Umbilical cord blood mononuclear cell proliferative response to house dust mite does not predict the development of allergic rhinitis and asthma

    Microsoft Academic Search

    Moira Chan-Yeung; Alexander Ferguson; Henry Chan; Helen Dimich-Ward; Wade Watson; Jure Manfreda; Allan Becker

    1999-01-01

    Background: Cord blood mononuclear cells (CBMNCs) have been found to proliferate when stimulated with food or inhalant allergens. The significance of this finding is not known. Objectives: We sought to determine the factors associated with proliferation of CBMNCs when stimulated with house dust mite (HDM) allergen and to determine whether proliferation of CBMNCs is associated with subsequent development of HDM

  16. NHEXAS PHASE I REGION 5 STUDY--STANDARD OPERATING PROCEDURE--ANALYSIS OF HOUSE DUST FOR ARSENIC (RTI/ACS-AP-209-121)

    EPA Science Inventory

    The purpose of this protocol is to provide guidelines for the analysis of wipes that were used in Lioy-Wainman-Weisel (LWW) surface samplers to collect house dust for arsenic (As). This method involves the extraction of the analyte from wipe samples using 50% ultra-pure nitric ac...

  17. A High-Molecular-Weight Mite Antigen (HM1) Fraction Aggravates Airway Hyperresponsiveness of Allergic Mice to House Dusts and Whole Mite Cultures

    Microsoft Academic Search

    Airo Tategaki; Seiji Kawamoto; Takahide Okuda; Tsunehiro Aki; Hiroshi Yasueda; Osamu Suzuki; Kazuhisa Ono; Seiko Shigeta

    2002-01-01

    Background: The house dust mite Dermatophagoides farinae is the most common aeroallergen causing human allergic asthma. Previously, we demonstrated that a high-molecular-weight allergenic fraction (HM1), which was abundant in D. farinae extracts, induced a proliferative response of T cells from healthy donors. The induction was mediated through the activation of macrophages without MHC class II restriction. In this study, we

  18. Monocyte-Derived Dendritic Cells Induce a House Dust Mite-Specific Th2 Allergic Inflammation in the Lung of Humanized SCID Mice: Involvement of CCR7

    Microsoft Academic Search

    Hamida Hammad; Bart N. Lambrecht; Pierre Pochard; Philippe Gosset

    In rodents, airway dendritic cells (DCs) capture inhaled Ag, undergo maturation, and migrate to the draining mediastinal lymph nodes (MLN) to initiate the Ag-specific T cell response. However, the role of human DCs in the pathogenesis of the Th2 cell- mediated disease asthma remains to be clarified. Here, by using SCID mice engrafted with T cells from either house dust

  19. Epidermal Cytokines IL1?, TNF-?, and IL12 in Patients with Atopic Dermatitis: Response to Application of House Dust Mite Antigens1

    Microsoft Academic Search

    Volker Junghans; Carsten Gutgesell; Thomas Jung; Christine Neumann

    1998-01-01

    Epidermal cytokines such as interleukin (IL)-1?, tumor necrosis factor-?, and IL-12 have been described to play a crucial role in the induction and elicitation phase of allergic contact dermatitis upon exposure to haptens. In this study we asked whether these cytokines may also play a role in the epidermis of patients with atopic dermatitis after the application of house dust

  20. CHARACTERIZATION OF IMMEDIATE AND LATE PHASE AIRWAY RESPONSES TO HOUSE DUST MITE CHALLENGE IN BROWN NORWAY RATS AND CORRELATIONS AMONG PHYSIOLOGICAL MEDIATORS

    EPA Science Inventory

    CHARACTERIZATION OF IMMEDIATE AND LATE PHASE AIRWAY RESPONSES TO HOUSE DUST MITE CHALLENGE IN BROWN NORWAY RATS AND CORRELATIONS AMONG PATHOPHYSIOLOGICAL MEDIATORS (P. SinghI, D.W. Winsett2, M.J. Daniels2, J. Richards2, K. Crissman2, D.L. Doerfler2 and M.I. Gilmour2, 1NCSU, Ra...

  1. NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE FOR ANALYSIS OF SOIL OR HOUSE DUST SAMPLES USING CHLORPYRIFOS ELISA SAMPLES (BCO-L-1.0)

    EPA Science Inventory

    This abstract is included for completeness of documentation, but this SOP was not used in the study. The purpose of this SOP is to describe the procedures for analyzing both Stage II and Stage III soil and vacuum-cleaner collected house dust samples, and Stage III air samples u...

  2. Treatment of Patients with Refractory Atopic Dermatitis Sensitized to House Dust Mites by Using Sublingual Allergen Immunotherapy

    PubMed Central

    Choi, Joon-Seok; Ryu, Ha-Ryeong; Yoon, Cheol-Hyun; Kim, Ji-Hoon; Baek, Jin-Ok; Roh, Joo-Young

    2015-01-01

    Even though atopic dermatitis (AD) is one of the most common chronic inflammatory skin diseases, its treatment remains a challenge in clinical practice, with most approaches limited to symptomatic, unspecific anti-inflammatory, or immunosuppressive treatments. Many studies have shown AD to have multiple causes that activate complex immunological and inflammatory pathways. However, aeroallergens, and especially the house dust mite (HDM), play a relevant role in the elicitation or exacerbation of eczematous lesions in many AD patients. Accordingly, allergen-specific immunotherapy has been used in AD patients with the aim of redirecting inappropriate immune responses. Here, we report three cases of refractory AD sensitized to HDM who were treated with sublingual immunotherapy. PMID:25673938

  3. Three-Year Follow-up Results of Sublingual Immunotherapy in Patients With Allergic Rhinitis Sensitized to House Dust Mites

    PubMed Central

    Kim, Shin Hye; Mun, Sue Jean; Han, Doo Hee; Kim, Jeong-Whun; Kim, Dong-Young

    2015-01-01

    Purpose This study investigated the long-term efficacy, safety, and compliance associated with sublingual immunotherapy (SLIT) in Korean patients with allergic rhinitis sensitized to house dust mites. Methods This is a retrospective cohort study. A total of 164 patients who were sensitized to Dermatophagoides pteronyssinus and Dermatophagoides farinae and who received SLIT were enrolled between November 2007 and January 2010. Each patient was followed up using a diary card, on which a symptom score, rescue medication score, and adverse events (AEs) were recorded. Results All allergic rhinitis symptoms improved after 3 years of SLIT (P<0.05), and the rescue medication score decreased with time (P<0.05). The incidence of AEs associated with SLIT was 31% (51 of 164 patients) during the first month of therapy, and there were no severe AEs. The dropout rate was 19.5% (32 of 164 patients) during the first month, 34% (56 of 164 patients) after 6 months, and 41% (68 of 164 patients) after 1 year of SLIT. The 3-year compliance rate was approximately 40% (65 of 164 patients). The most common causes of dropout during the first month of SLIT were high cost and inconvenience. The improvement in allergic symptoms was the most common cause of dropout after 6 months. Conclusions Allergic symptoms significantly decreased after 1 year of SLIT treatment, and this effect was sustained after 2 or 3 years of treatment. By increasing compliance through patient education, the 3-year use of SLIT for house dust mite allergies may be effective in the management of allergic rhinitis. PMID:25729618

  4. Levels of polybrominated diphenyl ethers in settled house dust from urban dwellings with resident preschool-aged children in Nanjing, China.

    PubMed

    Wang, Bing-Ling; Pang, Shu-tao; Zhang, Xiao-ling; Li, Xi-ling; Sun, Yong-gang; Lu, Xiao-mei; Zhang, Qi

    2015-01-01

    We investigated the levels and possible determinants of polybrominated diphenyl ethers (PBDEs) in the settled house-dust (SHD) of urban dwellings with resident preschool-aged children in Nanjing, China. The possible neurodevelopmental effects of house-dust PBDEs were also explored. SHD was collected from 216 urban houses. Levels of 8 PBDEs were measured by gas chromatography-negative chemical ionization mass spectrometry. The Child Behavior Checklist and the Gesell Development Inventory were used to evaluate the child's development. BDE47, BDE99, BDE153, BDE18, and BDE209 were detected in the SHD of >90 % of houses, of which BDE209 predominated. Most PBDEs were found at significantly greater levels in indoor than in outdoor dust (P < 0.05). Levels of BDE28 and BDE154 in houses with solid-wood floors were significantly greater than those in houses with plywood floors (P < 0.05). BDE154 levels in houses with wallpaper were significantly greater than those without wallpaper (P < 0.05). Greater BDE47 concentrations were found in houses with less natural ventilation time (linear trend P < 0.05). After dichotomization at the geometric mean concentration, BDE209 and total BDEs showed significant risks for depressed behavior problems and lower personal social developmental quotients (DQs); BDE99 and BDE153 indicated a risk for lower personal social DQs. In conclusion, PBDEs (especially BDE209) are ubiquitous in urban SHD in Nanjing residences. Natural ventilation and floor materials potentially influence PBDE levels in SHD. The potential adverse effect of postnatal exposure to PBDEs on the behavior and neurodevelopment of preschool-age children requires follow-up in larger studies. PMID:25034333

  5. Interleukin-1? controls allergic sensitization to inhaled house dust mite via the epithelial release of GM-CSF and IL-33

    PubMed Central

    Willart, Monique A.M.; Deswarte, Kim; Pouliot, Philippe; Braun, Harald; Beyaert, Rudi; Lambrecht, Bart N.

    2012-01-01

    House dust mite (HDM) is one of the most common allergens worldwide. In this study, we have addressed the involvement of IL-1 in the interaction between HDM and the innate immune response driven by lung epithelial cells (ECs) and dendritic cells (DCs) that leads to asthma. Mice lacking IL-1R on radioresistant cells, but not hematopoietic cells, failed to mount a Th2 immune response and did not develop asthma to HDM. Experiments performed in vivo and in isolated air–liquid interface cultures of bronchial ECs showed that TLR4 signals induced the release of IL-1?, which then acted in an autocrine manner to trigger the release of DC-attracting chemokines, GM-CSF, and IL-33. Consequently, allergic sensitization to HDM was abolished in vivo when IL-1?, GM-CSF, or IL-33 was neutralized. Thymic stromal lymphopoietin (TSLP) became important only when high doses of allergen were administered. These findings put IL-1? upstream in the cytokine cascade leading to epithelial and DC activation in response to inhaled HDM allergen. PMID:22802353

  6. [Nursery schools, a site for exposure to house dust mite allergens?].

    PubMed

    Rebmann, H; Weller, A

    1989-10-01

    In June 1988, 110 dust samples from carpets, cushions, mattresses and upholstered furniture were collected by vacuum cleaner in 33 municipal nursery schools. All samples were assessed with guanine test strips (Acarex). In all samples giving moderately or strongly positive results in these tests (guanine stages 2 and 3) and in 10 random samples each from of stages 1 (weakly positive) and 0 (negative), mites were counted by light microscope. In 36% of the nursery schools, objects with guanine stages 2 or 3 were found, which indicates a high allergen burden. The high guanine stages were found only in mattresses, cushions and upholstered furniture. Nursery schools can be source areas of significant allergen exposure relevant for children with dust mite allergies. PMID:2586533

  7. Aspergillus, Penicillium and Talaromyces isolated from house dust samples collected around the world

    PubMed Central

    Visagie, C.M.; Hirooka, Y.; Tanney, J.B.; Whitfield, E.; Mwange, K.; Meijer, M.; Amend, A.S.; Seifert, K.A.; Samson, R.A.

    2014-01-01

    As part of a worldwide survey of the indoor mycobiota, dust was collected from nine countries. Analyses of dust samples included the culture-dependent dilution-to-extinction method and the culture-independent 454-pyrosequencing. Of the 7?904 isolates, 2?717 isolates were identified as belonging to Aspergillus, Penicillium and Talaromyces. The aim of this study was to identify isolates to species level and describe the new species found. Secondly, we wanted to create a reliable reference sequence database to be used for next-generation sequencing projects. Isolates represented 59 Aspergillus species, including eight undescribed species, 49 Penicillium species of which seven were undescribed and 18 Talaromyces species including three described here as new. In total, 568 ITS barcodes were generated, and 391 ?-tubulin and 507 calmodulin sequences, which serve as alternative identification markers. PMID:25492981

  8. Indirect contact with pets can confound the effect of cleaning procedures for reduction of animal allergen levels in house dust.

    PubMed

    Munir, A K; Einarsson, R; Dreborg, S K

    1994-02-01

    To investigate the capacity of common vacuum cleaners and chemical treatment to reduce cat (Fel d I) and dog (Can f I) allergen content in house dust, 52 families with allergic children and no pets at home were recruited. Five groups of 10-11 families used their central vacuum cleaners (n = 10), their own old vacuum cleaners plus either tannic acid (n = 10) or placebo (n = 10) applied to carpets and upholstry after the first sample was collected on Day 0 or new vacuum cleaners equipped with either HEPA (high efficiency particulate air)- (n = 11) or microfilters (n = 10). Dust samples were collected from carpets and upholstered furniture in the living rooms and from the mattresses of the children on Days 0, 7, 21, and 35. Fel d I and Can f I allergens were determined by sandwich ELISA methods. Central, micro-filter and HEPA-filter vacuum cleaners did not reduce the concentrations nor the total amount/sampling area of Fel d I or Can f I. Tannic acid initially reduced (p < 0.05) both the concentration and the total amount of Fel d I by 30% and Can f I by 10%, but only for one week. The levels increased to base-line after 21-35 days. The concentrations of Fel d I increased 10-30 times in homes visited by cats or cat owners. We conclude, that tannic acid treatment reduced pet allergen concentrations and total amounts in dust for one week only.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8173637

  9. Systemic administration of an Fc?–Fc?-fusion protein in house dust mite sensitive nonhuman primates

    Microsoft Academic Search

    Michael R. Van Scott; Elisabeth Mertsching; Ella Negrou; Jeremy Miles; Howard W. Stallings; Candace Graff; Marilyn R. Kehry

    2008-01-01

    Crosslinking Fc?RI and Fc?RIIB receptors inhibits mast cell and basophil activation, decreasing mediator release. In this study, a fusion protein incorporating human Fc? and Fc? domains, hGE2, was shown to inhibit degranulation of human mast cells and basophils, and to exhibit efficacy in a nonhuman primate model of allergic asthma. hGE2 increased the provocative concentration of dust mite aeroallergen that

  10. Risk assessment of non-dietary exposure to polycyclic aromatic hydrocarbons (PAHs) via house PM2.5, TSP and dust and the implications from human hair

    NASA Astrophysics Data System (ADS)

    Wang, Wei; Huang, Min-juan; Chan, Chuen-Yu; Cheung, Kwai Chung; Wong, Ming Hung

    2013-07-01

    To evaluate the cancer risk due to non-dietary PAHs exposure in home environment (inhalation and ingestion), exposure to fine particles (PM2.5) and polycyclic aromatic hydrocarbons (PAHs) of PM2.5, total suspend particles (TSP) and dust in homes at two urban centers of Pearl River Delta were assessed. House PM2.5 bound PAHs in Guangzhou (GZ) ranged from 10.0 to 61.9 ng m-3 and 0.72 to 8.15 ng m-3 in Hong Kong (HK). PAH profiles found in PM2.5, TSP and dust were different than that in hair (dominated by Nap and Phe). Pyr and Flu in house dust significantly correlated with that in hair (r = 0.69; 0.55, p < 0.05) but no correlation was found between PAHs in hair and PM2.5. High correlation coefficients (r2 = 0.97/0.95, p < 0.01) were noted between dibenzo(a,h)anthracene (DBA) and Toxicity Equivalent Concentrations (TEQs) of dust and PM2.5. The lung cancer risks based on PM2.5 bound PAHs exposure in houses of GZ (10-5-10-4) were significantly higher than those of HK (10-6-10-5), which were also significantly higher than the cancer risks associated with house dust intake (10-7-10-5) in GZ. PAHs exposure via non-dietary route (PM2.5 and dust) was found to be 1-3 times higher than fish consumption for children and contributed to 52-76% of total PAHs intake for children and 24-50% for adults in GZ.

  11. Effect of floorcovering construction on content and vertical distribution of house dust mite allergen, Der p I.

    PubMed

    Causer, Simon; Shorter, Caroline; Sercombe, Jason

    2006-04-01

    Domestic floorcoverings often contain appreciable quantities of particulate pollutants, such as house dust mite allergen, Der p I. Exposure to Der p I is a risk factor for the development of mite sensitization and asthma. We investigated whether carpet construction was related to the Der p I content in normal use, and its vertical distribution. We hoped to inform development of methods to remove such material. Along with one hard flooring surface, a range of carpets with differing pile conformations (loop vs. cut), pile heights, yarn twists, and pile densities were placed in houses for 13 months. The carpets were later sectioned to allow profiling of Der p I throughout the pile strata using monoclonal antibody, enzyme-linked immunosorbent assay. Not surprisingly, significantly lower amounts of Der p I were found on hard flooring than any of the carpets, which all contained similar amounts of mite allergen. For all carpets, the Der p I concentration per unit area was found to be inversely related to the distance from the carpet backing. We conclude that carpet construction is not a good predictor of Der p I content in the home. We also suggest that, as carpet construction likely influences ease of disturbance of material within the pile, methods to remove or denature particulate pollutants such as Der p I will be most effective if they are able to target the bulk of allergenic material, found toward the base of the pile. PMID:16531289

  12. A Framework for Action To Make Private Housing Lead-Safe: A Proposal To Focus National Attention.

    ERIC Educational Resources Information Center

    Alliance to End Childhood Lead Poisoning, Washington, DC.

    This framework sets forth detailed proposals that are crucial to eliminating the epidemic of childhood lead poisoning in the United States. Private housing units can and must be made lead-safe, and this framework is designed to achieve that goal through specific requirements for property owners, a workable schedule, and mechanisms that reinforce…

  13. Divergent immune responses to house dust mite lead to distinct structural- functional phenotypes

    Microsoft Academic Search

    Jill R. Johnson; Filip K. Swirski; Beata U. Gajewska; Ryan E. Wiley; Ramzi Fattouh; Stephanie R. Pacitto; Jonathan K. Wong; Martin R. Stämpfli

    2007-01-01

    ABSTRACT Asthma is a chronic airway inflammatory,disease that encompasses,three cardinal processes: Th2-polarized inflammation, bronchial hyperreactivity and airway wall remodeling. However, the link between the immune-inflammatory phenotype and the structural-functional phenotype remains,to be fully defined. The objective of these studies was to evaluate the relationship between the immunological,nature of chronic airway inflammation,andthe development,of abnormal airway structure and function in a mouse

  14. Are You Pregnant? Prevent Lead Poisoning. Start Now.

    E-print Network

    . Most lead comes from paint in older homes. When old paint cracks and peels, it makes dangerous dust like sanding or scraping paint can make dangerous lead dust. Pregnant women should not be in the house during cleaning, painting, or remodeling a room with lead paint. If you live in an older home, have your

  15. Detection, Identification, and Quantification of Hydroxylated Bis(2-ethylhexyl)-Tetrabromophthalate Isomers in House Dust.

    PubMed

    Peng, Hui; Saunders, David M V; Sun, Jianxian; Codling, Garry; Wiseman, Steve; Jones, Paul D; Giesy, John P

    2015-03-01

    Ultra-High Resolution LC/mass spectrometry (LC-UHRMS; Thermo Fisher Q-Exactive) was used to identify two novel isomers of hydroxylated bis(2-ethylhexyl)-tetrabromophthalate (OH-TBPH) which were unexpectedly observed in a commercial standard of TBPH. By combining ultra-high resolution (UHR) mass spectra (MS(1)), mass errors to theoretical [TBPH-Br+O](-) were 2.1 and 1.0 ppm for the two isomers, UHR-MS(2) spectra and NMR analysis; the structures of the two compounds were identified as hydroxylated TBPH with a hydroxyl group on the aromatic ring. Relatively great proportions of the two isomers of OH-TBPH were detected in two technical products, Firemaster 550 (FM-550; 0.1% and 6.2%, respectively) and Firemaster BZ 54 (BZ-54; 0.1% and 7.9%), compared to a commercial standard (0.4% and 0.9%). To simultaneously analyze OH-TBPH isomers and TBPH in samples of dust, a method based on LC-UHRMS was developed to quantify the two compounds, using negative and positive ion modes, respectively. The instrumental limit of detection for TBPH was 0.01 ?g/L, which was 200-300 times better than traditional methods (2.5 ?g/L) based on gas chromatography-mass spectrometry. The analytical method combined with a Florisil cleanup was successfully applied to analyze TBPH and OH-TBPH in 23 indoor dust samples from Saskatoon, Saskatchewan, Canada. Two OH-TBPH isomers, OH-TBPH1 and OH-TBPH2, were detected in 52% and 91% of dust samples, respectively. Concentrations of OH-TBPH2 (0.35 ± 1.0 ng/g) were 10-fold greater than those of OH-TBPH1 (0.04 ± 0.88 ng/g) in dust, which was similar to profiles in FM-550 and BZ-54. TBPH was also detected in 100% of dust samples with a mean concentration of 733 ± 0.87 ng/g. A significant (p < 0.001) log-linear relationship was observed between TBPH and OH-TBPH isomers, further supporting the hypothesis of a common source of emission. Relatively small proportions of OH-TBPH isomers were detected in dust (0.01% ± 0.67 OH-TBPH1 and 0.1% ± 0.60 OH-TBPH2), which were significantly less than those in technical products (p < 0.001). This result indicated different environmental behaviors of OH-TBPH and TBPH. Detection of isomers of OH-TBPH is important, since compounds with phenolic groups have often shown relatively greater toxicities than nonhydroxylated analogues. Further study is warranted to clarify the environmental behaviors and potential toxicities of OH-TBPH isomers. PMID:25621784

  16. CDC Lead Poisoning Prevention and Treatment Recommendations for Refugee Children

    E-print Network

    exposure for children is deteriorated lead paint from older housing. · The primary route of exposure for children is by ingesting house dust or soil contaminated by leaded paint. · Young children have a higherCDC Lead Poisoning Prevention and Treatment Recommendations for Refugee Children 1. Background

  17. Natural variation in mite antigen density in house dust and relationship to residential factors.

    PubMed

    Kuehr, J; Frischer, T; Karmaus, W; Meinert, R; Barth, R; Schraub, S; Daschner, A; Urbanek, R; Forster, J

    1994-03-01

    To investigate the year-to-year variation of mite antigen density (Der p I, Der fI) in dust from mattresses and the relevance of residential factors for antigen load, information derived from an epidemiologic study including two surveys carried out in the households of a cohort of elementary school children (n = 1291) was analysed. When considering residences with measurements taken in both years in question (n = 1050), rank-correlation indicated a predominance of stability for both antigens (Der p I: rs = 0.82, P = 0.0001; Der f I: rs = 0.72, P = 0.0001). Using multiple regression analyses, significant associations between antigen concentrations and a variety of residential factors were found. Use of a blanket of animal hair, use of a cover or underblanket, wet spots in the bedroom, higher relative humidity and a low storey level were significantly associated with increased concentrations of Der p I, whereas inverse relationships between this antigen and room temperature, number of persons per m2 as well as use of underfloor heating were seen. Regarding Der fI, older mattresses, use of a cover or underblanket, higher weight of sampled dust, high educational level and higher ratio of inhabitants per m2 were significantly associated with increased concentrations of the antigen. On the other hand, lower Der fI concentrations were found when interior sprung mattresses were used and when the mattress was 'treated regularly'. In conclusion, two measurements, 1 year apart from each other, show that stability of mite antigen concentrations predominated.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8012854

  18. Assessment of in Vitro Lead Bioaccessibility in House Dust and Its Relationship to in Vivo Lead Relative Bioavailability

    E-print Network

    Ma, Lena

    pH produced higher Pb bioaccessibility because of enhanced Pb dissolution. When compared to mouse and Remediation, University of South Australia, Mawson Lakes, SA 5095, Australia § Soil and Water Science

  19. Genetically Engineered Lactococcus lactis Protect against House Dust Mite Allergy in a BALB/c Mouse Model

    PubMed Central

    Ai, Chunqing; Zhang, Qiuxiang; Ren, Chengcheng; Wang, Gang; Liu, Xiaoming; Tian, Fengwei; Zhao, Jianxin; Zhang, Hao; Chen, Yong Q.; Chen, Wei

    2014-01-01

    Background Mucosal vaccine based on lactic acid bacteria is an attractive concept for the prevention and treatment of allergic diseases, but their mechanisms of action in vivo are poorly understood. Therefore, we sought to investigate how recombinant major dust mite allergen Der p2-expressing Lactococcus lactis as a mucosal vaccine induced the immune tolerance against house dust mite allergy in a mouse model. Methods Three strains of recombinant L. lactis producing Der p2 in different cell components (extracellular, intracellular and cell wall) were firstly constructed. Their prophylactic potential was evaluated in a Der p2-sensitised mouse model, and immunomodulation properties at the cellular level were determined by measuring cytokine production in vitro. Results Der p2 expressed in the different recombinant L. lactis strains was recognized by a polyclonal anti-Der p2 antibody. Oral treatment with the recombinant L. lactis prior sensitization significantly prevented the development of airway inflammation in the Der p2-sensitized mice, as determined by the attenuation of inflammatory cells infiltration in the lung tissues and decrease of Th2 cytokines IL-4 and IL-5 levels in bronchoalveolar lavage. In addition, the serum allergen-specific IgE levels were significantly reduced, and the levels of IL-4 in the spleen and mesenteric lymph nodes cell cultures were also markedly decreased upon allergen stimulation in the mice fed with the recombinant L. lactis strains. These protective effects correlated with a significant up-regulation of regulatory T cells in the mesenteric lymph nodes. Conclusion Oral pretreatment with live recombinant L. lactis prevented the development of allergen-induced airway inflammation primarily by the induction of specific mucosal immune tolerance. PMID:25290938

  20. House dust mite extracts activate cultured human dermal endothelial cells to express adhesion molecules and secrete cytokines.

    PubMed

    Arlian, Larry G; Elder, B Laurel; Morgan, Marjorie S

    2009-05-01

    The human skin contacts molecules from house dust mites that are ubiquitous in many environments. These mite-derived molecules may penetrate the skin epidermis and dermis and contact microvascular endothelial cells and influence their function. The purpose of this study was to determine the response of normal human dermal microvascular endothelial cells to extracts of the dust mites, Dermatophagoides farinae, D. pteronyssinus, and Euroglyphus maynei with and without endotoxin (lipopolysaccharide). Endothelial cells were stimulated with mite extracts and the expression of surface molecules and the secretion of cytokines were measured in the absence and presence of polymyxin B to bind endotoxin. All three mite extracts stimulated endothelial cells to express intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin and to secrete interleukin (IL)-6, IL-8, monocyte chemoattractant protein (MCP-1), and granulocyte/macrophage colony stimulating factor (GM-CSF). Euroglyphus maynei-induced expression of all the cell surface molecules was not inhibited when the endotoxin activity in the mite extract was inhibited. In contrast, endothelial cells challenged with D. farinae or D. pteronyssinus extract depleted of endotoxin activity expressed only constitutive levels of ICAM-1, VCAM-1, and E-selectin. D. farinae and E. maynei extracts depleted of endotoxin activity still induced secretion of IL-8 and MCP-1 but at reduced levels. Only constitutive amounts of IL-6, G-CSF, and GM-CSF were secreted in response to any of the endotoxin-depleted mite extracts. Extracts of D. farinae, D. pteronyssinus, and E. maynei contain both endotoxins and other molecules that can stimulate expression of cell adhesion molecules and chemokine receptors and the secretion of cytokines by normal human microvascular endothelial cells. PMID:19496432

  1. An Evaluation of One-Time Professional Cleaning in Homes with Lead-Based Paint Hazards

    Microsoft Academic Search

    Ellen R. Tohn; Sherry L. Dixon; Jonathan W. Wilson; Warren A. Galke; C. Scott Clark

    2003-01-01

    A key challenge in reducing the burden of lead poisoning is to identify cost-effective interventions that minimize lead-based paint hazards. One-time professional cleaning of lead-contaminated dust and debris was conducted in 37 housing units with deteriorated lead-based paint and dust lead hazards. These study units are a subset of a larger cohort of the nearly 3500 housing units enrolled in

  2. Lead in housing paints: An exposure source still not taken seriously for children lead poisoning in China

    Microsoft Academic Search

    G. Z. Lin; R. F. Peng; Q. Chen; Z. G. Wu; L. Du

    2009-01-01

    After prohibitions on lead gasoline additives, which have proved to be a public health accomplishment world wide, many countries focus on other exposure source of children lead poisoning. Removing lead from paints is one of the important measures. Although there have been regulatory limits on lead in paints in China, evidence reported in this article indicates that lead-based paints were

  3. MHC class II-restricted presentation of the major house dust mite allergen Der p 1 Is GILT-dependent: implications for allergic asthma.

    PubMed

    West, Laura Ciaccia; Grotzke, Jeff E; Cresswell, Peter

    2013-01-01

    Gamma-interferon-inducible lysosomal thiol reductase (GILT) is known to reduce disulfide bonds present in proteins internalized by antigen presenting cells, facilitating optimal processing and presentation of peptides on Major Histocompatibility Complex class II molecules, as well as the subsequent activation of CD4-positive T lymphocytes. Here, we show that GILT is required for class II-restricted processing and presentation of immunodominant epitopes from the major house dust mite allergen Der p 1. In the absence of GILT, CD4-positive T cell responses to Der p 1 are significantly reduced, resulting in mitigated allergic airway inflammation in response to Der p 1 and house dust mite extracts in a murine model of asthma. PMID:23326313

  4. Brominated flame retardants in house dust from e-waste recycling and urban areas in South China: Implications on human exposure

    Microsoft Academic Search

    Jing Wang; Yun-Juan Ma; She-Jun Chen; Mi Tian; Xiao-Jun Luo; Bi-Xian Mai

    2010-01-01

    Brominated flame retardants (BFRs) were examined in house dust from the electronic waste (e-waste) recycling and urban areas of South China. The concentrations of polybrominated diphenyl ethers (PBDEs) were in the range of 227–160,000ng\\/g in the e-waste recycling area and 530–44,000ng\\/g in the urban area. These values were much higher than other BFRs, except for novel decabromodiphenyl ethane (DBDPE) whose

  5. Interference in foraging behaviour of European and American house dust mites Dermatophagoides pteronyssinus and Dermatophagoides farinae (Acari: Pyroglyphidae) by catmint, Nepeta cataria (Lamiaceae).

    PubMed

    Khan, M A; Jones, I; Loza-Reyes, E; Cameron, M M; Pickett, J A; Birkett, M A

    2012-05-01

    The European and American house dust mites, Dermatophagoides pteronyssinus and D. farinae, have a huge impact upon human health worldwide due to being the most important indoor trigger of atopic diseases such as asthma, rhinitis and atopic dermatitis. Preceding studies have shown that the behavioural response of house dust mites towards volatile chemicals from food sources can be assessed using a Y-tube olfactometer assay. In the current study, we used this assay to investigate, for the first time, the ability of the essential oil of the catmint plant, Nepeta cataria (Lamiaceae), known to repel other ectoparasites affecting human and animal health, to interfere with the attraction of D. pteronyssinus and D. farinae towards a standard food source (fish flakes). Two distinct chemotypes (A and B), enriched in the iridoid compounds (4aS,7S,7aR)-nepetalactone and (4aS,7S,7aS)-nepetalactone, and the sesquiterpene (E)-(1R,9S)-caryophyllene, were used. Initial assays with a hexane extract of fish flakes (FF extract) confirmed attraction of mites to this positive control (P < 0.001 and P < 0.05 for D. pteronyssinus and D. farinae respectively), but when presented in combination with either N. cataria chemotype, tested across a range of doses (10, 1, 0.1 and 0.01 ?g), decreasing attraction of mites to their food source was observed as the dose augmented. Our study shows that N. cataria, enriched in iridoid nepetalactones and (E)-(1R,9S)-caryophyllene, exhibits potent repellent activity for house dust mites, and has the potential for deployment in control programmes based on interference with normal house dust mite behaviour. PMID:22382713

  6. Comparison of Allergen-Induced Late Inflammatory Reactions in the Nose and in the Skin in House Dust Mite-Allergic Patients with or without Asthma

    Microsoft Academic Search

    Christa E. Lopuhaä; Mariëlle J. de Riemer; Theo A. Out; Deman H. S. Sjamsoedin; Rob C. Aalberse; Henk M. Jansen; Jaring S. van der Zee

    2003-01-01

    Background: It remains to be established which factors contribute to the occurrence of asthma in allergic individuals. We hypothesized that differences in the late allergic inflammatory reaction to allergen between asthmatic and non-asthmatic house dust mite-allergic individuals might contribute to the difference in the clinical presentation of allergy. Aim: To compare allergen-induced changes in parameters for cellular inflammation during the

  7. Relation between skin tests, inhalation tests, and histamine release from leucocytes and IgE in house-dust mite allergy

    Microsoft Academic Search

    K F Kerrebijn; H J Degenhart; A Hammers

    1976-01-01

    This study was concerned with the correlation between skin test, bronchial provocation test, and histamine release from leucocytes and the serum level of total and allergen-specific IgE in patients atopic to house-dust mite allergen (Dermatophagiodes pteronyssinus) as measured by an intracutaneous skin test. It is concluded that, assuming a positive provocation test to be evidence of allergy, estimation of the

  8. Regulation of house dust mite responses by intranasally administered peptide: transient activation of CD4 + T cells precedes the development of tolerance in vivo

    Microsoft Academic Search

    Gerard F. Hoyne; Brigitte A. Askonas; Charlotte Hetzel; Wayne R. Thomas; Jonathan R. Lamb

    1996-01-01

    We have previously demonstrated that intranasal (l.n.) administration of an immunodomlnant peptide (p1 111-139) derived from the house dust mite (HDM) allergen Der p 1 Inhibits antigen- specific CD4+ T cell responses in H-2b mice. Here we report that i.n. peptide induced a rapid but transient activation of MHC class II restricted CD4+ T cells that peaked 4 days after

  9. False-positive skin prick test responses to commercially available dog dander extracts caused by contamination with house dust mite (Dermatophagoides pteronyssinus) allergens

    Microsoft Academic Search

    Maurits J. van der Veen; Marcel Mulder; Agnes M. Witteman; Ronald van Ree; Rob C. Aalberse; Henk M. Jansen; Jaring S. van der Zee

    1996-01-01

    BACKGROUND: In an outpatient population, a high frequency of positive skin prick test responses to dog dander was found in the absence of detectable IgE to dog dander in the RAST. The majority of these patients were sensitized to house dust mites(Dermatophagoides pteronyssinus)and had no obvious dog-related allergic symptoms. These findings prompted us to investigate whether dog dander skin test

  10. Vaccination with the recombinant allergen ProDer p 1 complexed with the cationic lipid DiC14-amidine prevents allergic responses to house dust mite

    Microsoft Academic Search

    Alain Jacquet; Jean-François Vanderschrick; Michel Vandenbranden; Abdelatif Elouahabi; Mauro Magi; Lida Garcia; Jean-Marie Ruysschaert

    2005-01-01

    The present study evaluated the prophylactic potential of ProDer p 1, the recombinant precursor form of the major mite allergen Der p 1, combined with the cationic lipid diC14-amidine in a murine model of house dust mite allergy. Naďve mice vaccinated with the amidine\\/allergen complex developed a Th1-biased immune response characterized by the absence of specific IgE, the production of

  11. Penetration of light into carpet, and responses of the European house-dust mite ( Dermatophagoides pteronyssinus ) to varying light intensity and diurnal cycle

    Microsoft Academic Search

    Simon Causer; Caroline Shorter

    2004-01-01

    This study examined the question of what effect exposure to light might play in determining the vertical distribution of house-dust\\u000a mites in carpet, and the degree to which light penetrates worn and unworn carpets of different pile conformation (loop- versus\\u000a cut-pile), height and colour. The effect on population increase of a diurnal lighting cycle versus continual darkness was\\u000a also investigated.

  12. The House Dust Mite Allergen Der p1 Catalytically Inactivates ? 1Antitrypsin by Specific Reactive Centre Loop Cleavage: A Mechanism That Promotes Airway Inflammation and Asthma

    Microsoft Academic Search

    Noor A. Kalsheker; Susan Deam; Louise Chambers; Suneal Sreedharan; Keith Brocklehurst; David A. Lomas

    1996-01-01

    Der p1, a cysteine proteinase derived from the house dust mite (HDM)Dermatophagoides pteronyssinus,is a major component of the allergic immune response in HDM atopic individuals. Recent evidence suggests that cysteine proteinase activity is important in the disease process as it increases the permeability of the allergen in the respiratory tract and disrupts the regulation of IgE synthesis.Der p1 is found

  13. Secretion of MCP?1, IL?8 and IL?6 induced by house dust mite, dermatophagoides pteronissinus in human eosinophilic EOL?1 cells

    Microsoft Academic Search

    In Sik Kim

    2009-01-01

    The house dust mite (Dermatophagoides pteronissinus) is an important factor in triggering allergic diseases. The function of eosinophils, particularly in the production of cytokine or chemokine, is critical in understanding the pathogenesis of inflammatory diseases. In this study, we examined whether D. pteronissinus extract (DpE) induces the expression of monocyte chemotactic protein 1 (MCP?1)\\/ CCL2, IL?8\\/CXCL8, and IL?6 that mediate

  14. Crystallization and Preliminary X-ray Analysis of Der f 2, a Potent Allergen Derived from the House Dust Mite

    NASA Technical Reports Server (NTRS)

    Roeber, Dana; Achari, Aniruddha; Takai, Toshiro; Okumura, Yasushi; Scott, David L.; Curreri, Peter (Technical Monitor)

    2002-01-01

    Although a number of allergens have been identified and isolated, the underlying molecular basis for the potent immune response is poorly understood. House dust mites (Dermatophugoides sp.) are particularly ubiquitous contributors to atopy in developed countries. The rhinitis, dermatitis, and asthma associated with allergic reactions to these arthropods are often caused by relatively small (125-129 amino acids) mite proteins of unclear biological function. Der f 2, a major allergen from the mite Dermatophagoides farinae, has been recombinantly expressed and characterized. The Der f 2 protein has been crystallized in our laboratory and a native data set collected at a synchrotron source. The crystals belong to the orthorhombic space group I422 with unit cell parameters of a = 95.2 Angstroms, b = 95.2 Angstroms, and c = 103.3 Angstroms. An essentially complete (97.2%) data set has been collected to 2.4 Angstroms. Attempts to solve the crystal structure of Der f 2 by molecular replacement using the available NMR coordinates for either Der f 2 or Der p 2 (the homologous protein from D. pterovssinus) failed to reveal a creditable solution.

  15. Der p 11 is a major allergen for house dust mite-allergic patients suffering from atopic dermatitis.

    PubMed

    Banerjee, Srinita; Resch, Yvonne; Chen, Kuan-Wei; Swoboda, Ines; Focke-Tejkl, Margit; Blatt, Katharina; Novak, Natalija; Wickman, Magnus; van Hage, Marianne; Ferrara, Rosetta; Mari, Adriano; Purohit, Ashok; Pauli, Gabrielle; Sibanda, Elopy N; Ndlovu, Portia; Thomas, Wayne R; Krzyzanek, Vladislav; Tacke, Sebastian; Malkus, Ursula; Valent, Peter; Valenta, Rudolf; Vrtala, Susanne

    2015-01-01

    House dust mites (HDMs) belong to the most potent indoor allergen sources worldwide and are associated with allergic manifestations in the respiratory tract and the skin. Here we studied the importance of the high-molecular-weight group 11 allergen from Dermatophagoides pteronyssinus (Der p 11) in HDM allergy. Sequence analysis showed that Der p 11 has high homology to paramyosins from mites, ticks, and other invertebrates. A synthetic gene coding for Der p 11 was expressed in Escherichia coli and rDer p 11 purified to homogeneity as folded, alpha-helical protein as determined by circular dichroism spectroscopy. Using antibodies raised against rDer p 11 and immunogold electron microscopy, the allergen was localized in the muscle beneath the skin of mite bodies but not in feces. IgE reactivity of rDer p 11 was tested with sera from HDM-allergic patients from Europe and Africa in radioallergosorbent test-based dot-blot assays. Interestingly, we found that Der p 11 is a major allergen for patients suffering from atopic dermatitis (AD), whereas it is only a minor allergen for patients suffering from respiratory forms of HDM allergy. Thus, rDer p 11 might be a useful serological marker allergen for the identification of a subgroup of HDM-allergic patients suffering from HDM-associated AD. PMID:24999597

  16. House-dust mite allergen and ozone exposure decreases histamine H3 receptors in the brainstem respiratory nuclei

    SciTech Connect

    Sekizawa, Shin-ichi, E-mail: ssekizawa@ucdavis.ed [Department of Pharmacology, School of Medicine, University of California Davis, GBSF Rm. 3617, 451 Health Sciences Drive, Davis, CA 95616-0635 (United States); Bechtold, Andrea G.; Tham, Rick C. [Department of Pharmacology, School of Medicine, University of California Davis, GBSF Rm. 3617, 451 Health Sciences Drive, Davis, CA 95616-0635 (United States); Kott, Kayleen S. [Department of Pharmacology, School of Medicine, University of California Davis, GBSF Rm. 3617, 451 Health Sciences Drive, Davis, CA 95616-0635 (United States); Department of Pediatrics, School of Medicine, University of California Davis, Davis, CA 95616-0635 (United States); Hyde, Dallas M. [School of Medicine, California National Primate Research Center, University of California Davis, Davis, CA 95616-0635 (United States); Joad, Jesse P. [Department of Pediatrics, School of Medicine, University of California Davis, Davis, CA 95616-0635 (United States); Bonham, Ann C. [Department of Pharmacology, School of Medicine, University of California Davis, GBSF Rm. 3617, 451 Health Sciences Drive, Davis, CA 95616-0635 (United States)

    2010-09-15

    Allergic airway diseases in children are a common and a growing health problem. Changes in the central nervous system (CNS) have been implicated in contributing to some of the symptoms. We hypothesized that airway allergic diseases are associated with altered histamine H3 receptor expression in the nucleus tractus solitarius (NTS) and caudal spinal trigeminal nucleus, where lung/airway and nasal sensory afferents terminate, respectively. Immunohistochemistry for histamine H3 receptors was performed on brainstem sections containing the NTS and the caudal spinal trigeminal nucleus from 6- and 12-month-old rhesus monkeys who had been exposed for 5 months to house dust mite allergen (HDMA) + O{sub 3} or to filtered air (FA). While histamine H3 receptors were found exclusively in astrocytes in the caudal spinal trigeminal nucleus, they were localized to both neuronal terminals and processes in the NTS. HDMA + O{sub 3} exposure significantly decreased histamine H3 receptor immunoreactivity in the NTS at 6 months and in the caudal spinal trigeminal nucleus at 12 months of age. In conclusion, exposing young primates to HDMA + O{sub 3} changed histamine H3 receptor expression in CNS pathways involving lung and nasal afferent nerves in an age-related manner. Histamine H3 receptors may be a therapeutic target for allergic asthma and rhinitis in children.

  17. Allergen expression in the European house dust mite Dermatophagoides pteronyssinus throughout development and response to environmental conditions.

    PubMed

    Vidal-Quist, J C; Ortego, F; Lombardero, M; Castańera, P; Hernández-Crespo, P

    2015-06-01

    House dust mites are a major source of allergy worldwide. While diagnosis and treatment based on mite extracts have remarkably advanced, little information exists on the expression of allergens in mites. We have studied gene expression of eight Dermatophagoides pteronyssinus (Trouessart) (Acari: Pyroglyphidae) allergens (Der p 1, 2, 3, 4, 5, 7, 10 and 21). All allergens showed higher transcription in nymphs compared with larvae or adults, with the only exception of Der p 10. The transcription of Der p 4 and Der p 10, together with the transcription and protein ratios Der p 1 to Der p 2, were higher in males than in females. One-week exposure of mite cultures to 16 or 35?°C (versus 24?°C) or low RH (44% versus 76%) significantly influenced the allergen gene transcription profile. Our results demonstrate that allergen expression is quantitatively and/or qualitatively influenced by mite development and sex, as well as by the environment. We suggest that monitoring allergen gene expression may be a useful tool to assist the optimization of mite cultures in the production of standardized allergenic extracts for clinical use. PMID:25565338

  18. Group 10 allergens (tropomyosins) from house-dust mites may cause covariation of sensitization to allergens from other invertebrates

    PubMed Central

    Inam, Muhammad; Ismail, Muhammad; Chaudhary, Farhana Riaz

    2012-01-01

    Group 10 allergens (tropomyosins) have been assumed to be a major cause of cross-reactivity between house-dust mites (HDMs) and other invertebrates. Despite all of the published data regarding the epidemiology, percent IgE binding and level of sensitization in the population, the role of tropomyosin as a cross-reactive allergen in patients with multiple allergy syndrome still remains to be elucidated. Homology between amino acid sequences reported in allergen databases of selected invertebrate tropomyosins was determined with Der f 10 as the reference allergen. The 66.9 and 54.4% identities were found with selected crustacean and insect species, respectively, whereas only 20.4% identity was seen with mollusks. A similar analysis was performed using reported B-cell IgE-binding epitopes from Met e1 (shrimp allergen) and Bla g7 (cockroach allergen) with other invertebrate tropomyosins. The percent identity in linear sequences was higher than 35% in mites, crustaceans, and cockroaches. The polar and hydrophobic regions in these groups were highly conserved. These findings suggest that tropomyosin may be a major cause of covariation of sensitization between HDMs, crustaceans, and some species of insects and mollusks. PMID:23342293

  19. Dendritic cells induce Th2-mediated airway inflammatory responses to house dust mite via DNA-dependent protein kinase.

    PubMed

    Mishra, Amarjit; Brown, Alexandra L; Yao, Xianglan; Yang, Shutong; Park, Sung-Jun; Liu, Chengyu; Dagur, Pradeep K; McCoy, J Philip; Keeran, Karen J; Nugent, Gayle Z; Jeffries, Kenneth R; Qu, Xuan; Yu, Zu-Xi; Levine, Stewart J; Chung, Jay H

    2015-01-01

    DNA-dependent protein kinase (DNA-PK) mediates double-stranded DNA break repair, V(D)J recombination and immunoglobulin class switch recombination, as well as innate immune and pro-inflammatory responses. However, there is limited information regarding the role of DNA-PK in adaptive immunity mediated by dendritic cells (DCs), which are the primary antigen-presenting cells in allergic asthma. Here we show that house dust mite induces DNA-PK phosphorylation, which is a marker of DNA-PK activation, in DCs via the generation of intracellular reactive oxygen species. We also demonstrate that pharmacological inhibition of DNA-PK, as well as the specific deletion of DNA-PK in DCs, attenuates the induction of allergic sensitization and Th2 immunity via a mechanism that involves the impaired presentation of mite antigens. Furthermore, pharmacological inhibition of DNA-PK following antigen priming similarly reduces the manifestations of mite-induced airway disease. Collectively, these findings suggest that DNA-PK may be a potential target for treatment of allergic asthma. PMID:25692509

  20. Clinical evaluation of the effect of anti-allergic mattress covers in patients with moderate to severe asthma and house dust mite allergy: a randomised double blind placebo controlled study

    Microsoft Academic Search

    L H M Rijssenbeek-Nouwens; A J Oosting; M S de Bruin-Weller; I Bregman; J G R de Monchy; D S Postma

    2002-01-01

    Background: The use of anti-allergic mattress covers in patients with asthma can result in a large reduction in the level of house dust mite allergen in dust samples. Apart from a reduction in histamine induced bronchial hyperresponsiveness, there are few data on the effect of mattress covers on clinical efficacy and quality of life in patients with moderate to severe

  1. Lead poisoning as possible cause of deaths at the Swedish House at Kapp Thordsen, Spitsbergen, winter 1872-3

    PubMed Central

    2009-01-01

    Objective To investigate cause of death in 17 sealers who died in the Swedish house in Kapp Thordsen, Spitsbergen, during the winter of 1872-3. Design Analysis of skeletal samples from one sealer’s grave. Setting Field trip to Spitsbergen to exhume skeletal remains. Subjects One of 17 sailors who died in 1872-3. Results No objective signs of scurvy were found. The concentration of lead in the bone samples was 102.05 µg/g. Conclusions The high concentrations of lead indicate that this man died from lead poisoning, probably from food tins. The absence of macroscopic signs of scurvy supports this theory. PMID:19965937

  2. Department of Housing and Urban Development, Office of Healthy Homes and Lead Hazard Control

    MedlinePLUS

    ... Officer Office of Economic Resilience Community Planning and Development Office of Hearings and Appeals Congressional and Intergovernmental ... of Strategic Planning & Management Equal Employment Opportunity Policy Development and Research Fair Housing / Equal Opportunity Public Affairs ...

  3. Paint as a source of recontamination of houses in urban environments and its role in maintaining elevated blood leads in children

    Microsoft Academic Search

    Brian L. Gulson; Jeffrey J. Davis; Jason Bawden-Smith

    1995-01-01

    A detailed lead isotopic and scanning electron microscope investigation of particulates from three houses in urban Sydney, previously decontaminated by their owners, has shown that they have been recontaminated over varying periods, as short as 6 months. The source of recontamination is lead paint from adjoining dwellings whose paint thoroughly deteriorated, as well as from unknown sources. In one house,

  4. Morus alba L. suppresses the development of atopic dermatitis induced by the house dust mite in NC/Nga mice

    PubMed Central

    2014-01-01

    Background Morus alba, a medicinal plant in Asia, has been used traditionally to treat diabetes mellitus and hypoglycemia. However, the effects of M. alba extract (MAE) on atopic dermatitis have not been verified scientifically. We investigated the effects of MAE on atopic dermatitis through in vitro and in vivo experiments. Methods We evaluated the effects of MAE on the production of nitric oxide (NO) and prostaglandin E2 (PGE2) in RAW 264.7, as well as thymus and activation-regulated chemokine (TARC/CCL17) in HaCaT cells. In an in vivo experiment, atopic dermatitis was induced by topical application of house dust mites for four weeks, and the protective effects of MAE were investigated by measuring the severity of the skin reaction on the back and ears, the plasma levels of immunoglobulin E (IgE) and histamine, and histopathological changes in the skin on the back and ears. Results MAE suppressed the production of NO and PGE2 in RAW 264.7 cells, as well as TARC in HaCaT cells, in a dose-dependent manner. MAE treatment of NC/Nga mice reduced the severity of dermatitis and the plasma levels of IgE and histamine. MAE also reduced the histological manifestations of atopic dermatitis-like skin lesions such as erosion, hyperplasia of the epidermis and dermis, and inflammatory cell infiltration in the skin on the back and ears. Conclusion Our results suggest that MAE has potent inhibitory effects on atopic dermatitis-like lesion and may be a beneficial natural resource for the treatment of atopic dermatitis. PMID:24755250

  5. High Degree of Overlap between Responses to a Virus and to the House Dust Mite Allergen in Airway Epithelial Cells

    PubMed Central

    Golebski, Korneliusz; Luiten, Silvia; van Egmond, Danielle; de Groot, Esther; Röschmann, Kristina Irene Lisolette; Fokkens, Wytske Johanna; van Drunen, Cornelis Maria

    2014-01-01

    Background Airway epithelium is widely considered to play an active role in immune responses through its ability to detect changes in the environment and to generate a microenvironment for immune competent cells. Therefore, besides its role as a physical barrier, epithelium affects the outcome of the immune response by the production of various pro-inflammatory mediators. Methods We stimulated airway epithelial cells with viral double stranded RNA analogue poly(I:C) or with house dust mite in a time course of 24 hours. In order to determine cytokines production by stimulated cells, we performed multiplex enzyme linked immunosorbant assay (ELISA). Results We demonstrate that the temporal pattern of the genes that respond to virus exposure in airway epithelium resembles to a significant degree their pattern of response to HDM. The gene expression pattern of EGR1, DUSP1, FOSL1, JUN, MYC, and IL6 is rather similar after viral (poly(I:C)) and HDM exposure. However, both triggers also induce a specific response (e.g. ATF3, FOS, and NFKB1). We confirmed these data by showing that epithelial cells produce a variety of similar mediators in response to both poly(I:C) and HDM challenge (IL1-RA, IL-17, IFN-? and MIP1-?), sometimes with a quantitative difference in response (IL2-R, IL-6, IL-8, MCP-1, MIG, and HGF). Interestingly, only four mediators (IL-12, IP-10, RANTES and VEGF) where up-regulated specifically by poly(I:C) and not by HDM. Additionally, we report that pre-exposure to HDM deregulates production of cytokines and mediators in response to poly(I:C). Conclusions Epithelial cells responses to the HDM-allergen and a virus strongly resemble both in gene expression and in protein level explaining why these two responses may affect each other. PMID:24498371

  6. House dust mite-specific immunoglobulin E and longitudinal exhaled nitric oxide measurements in children with atopic asthma

    PubMed Central

    Lee, Youn Kyung; Yang, Sohyoung; Park, Joohyun; Kim, Heon

    2015-01-01

    Purpose House dust mite (HDM) has been suggested to be the most important aeroallergen responsible for atopic asthma in Korea. We aimed to investigate that specific IgE antibodies to HDM and other common indoor aeroallergens contribute differently to total serum IgE and show different relationships with longitudinal fractional exhaled nitric oxide (FeNO) measurements in Korean atopic asthmatic patients. Methods A total of 193 children aged 8 to 16 years with intermittent or mild persistent atopic asthma were recruited. Sera were assayed for total IgE and specific IgE antibodies to HDM and other common indoor allergens. FeNO was serially measured 10 times or more over 2 years when subjects were not receiving controller medications. Results In 152 children who completed the study, IgE antibodies to specific HDM were more prevalent than those to other common indoor aeroallergens. In addition, IgE antibody titers to HDM were the strongest contributor to total IgE increases. Furthermore, only HDM-specific IgE antibody titer significantly correlated with maximum FeNO (r=0.21, P=0.029) and the rate of FeNO higher than 21 parts per billion (ppb) (r=0.30, P=0.002). Eight patients (5%) were found to have maximum FeNO of 21 ppb or less, suggesting the presence of a low FeNO phenotype among atopic asthmatic patients. Conclusion The quantity of HDM-specific IgE antibody provides a possible explanation for increases of total IgE and significantly correlates with the amount and frequency of FeNO increases in Korean atopic asthmatic patients.

  7. Dectin-2 Regulates the Effector Phase of House Dust Mite-Elicited Pulmonary Inflammation Independently from its Role in Sensitization

    PubMed Central

    Parsons, Matthew W.; Li, Li; Wallace, Aaron M.; Lee, Min Jung; Katz, Howard R.; Fernandez, James M.; Saijo, Shinobu; Iwakura, Yoichiro; Austen, K. Frank; Kanaoka, Yoshihide; Barrett, Nora A.

    2014-01-01

    The myeloid C-type lectin receptor Dectin-2 directs the generation of Th2 and Th17 immune responses to the house dust mite Dermatophagoides farinae (Df) through the generation of cysteinyl leukotrienes (cys-LTs) and pro-inflammatory cytokines, respectively, but a role for Dectin-2 in effector phase responses has not been described. Here, we demonstrate that administration of the Dectin-2 mAb solely at the time of Df challenge abrogated eosinophilic and neutrophilic inflammation in the bronchoalveolar lavage (BAL) fluid and Th1, Th2, and Th17 inflammation in the lung of previously sensitized mice. Furthermore, Dectin-2 null mice (Clec4n?/?) sensitized with the adoptive transfer of Df-pulsed wild-type (WT) bone marrow-derived DCs (BMDCs) also had less Df-elicited pulmonary inflammation, supporting an effector function for Dectin-2. The protection from pulmonary inflammation seen with the Dectin-2 mAb or in Clec4n?/? mice was associated with little or no reduction in lung-draining lymph node cells or their cytokine production, and with no reduction in serum IgE. WT and Clec4n?/? mice recipients, sensitized with Df-pulsed WT BMDCs, had comparable levels of Df-elicited IL-6, IL-23, TNF-?, and cys-LTs in the lung. By contrast, Df-elicited CCL4 and CCL8 production from pulmonary CD11c+CD11b+Ly6C+ and CD11c+CD11b+Ly6C?CD64+ monocyte-derived DCs was reduced in Clec4n?/? recipients. Addition of CCL8 at the time of Df challenge abrogated the protection from eosinophilic, neutrophilic, and Th2 pulmonary inflammation seen in Clec4n?/? recipients. Taken together, these results reveal that Dectin-2 regulates monocyte-derived DC function in the pulmonary microenvironment at Df challenge to promote the local inflammatory response. PMID:24453247

  8. Proteins and endotoxin in house dust mite extracts modulate cytokine secretion and gene expression by dermal fibroblasts

    PubMed Central

    Rockwood, Jananie; Morgan, Marjorie S.; Arlian, Larry G.

    2013-01-01

    House dust mite extracts used for diagnostic tests and immunotherapy contain bioreactive molecules including proteins and endotoxin. These extracts can influence the cytokine secretion and adhesion molecule expression by cells in the skin and lung airways. The aim of this study was to determine the role of proteins and endotoxin in mite extracts in modulating gene expression and cytokine secretion by human dermal fibroblasts. Cultured normal human dermal fibroblasts were stimulated with whole mite extracts, mite extracts boiled to denature proteins, or mite extracts treated with polymyxin B to inactivate lipopolysaccharide. Gene expression and secretion of interleukin-6 (IL-6), IL-8, and monocyte chemoattractant protein-1 (MCP-1) were determined after 6 h of stimulation. Whole Dermatophagoides farinae, D. pteronyssinus and Euroglyphus maynei extracts induced dose-dependent IL-6 and IL-8 secretion. In addition, D. farinae and E. maynei induced secretion of MCP-1. D. farinae and E. maynei also induced parallel cytokine gene expression. Cells stimulated with boiled D. farinae extract showed moderate to marked reductions in IL-6 and IL-8 secretion. In contrast, boiled D. pteronyssinus and E. maynei extracts induced equal or greater cytokine secretions than untreated extracts. The stimulating properties were reduced for all three extracts following treatment with polymyxin B. Our data suggest that both endotoxin and proteins in mite extracts modulate the secretion of cytokines by dermal fibroblasts. The biological activities of D. farinae, D. pteronyssinus, and E. maynei extracts are not equivalent. There appears to be a lipopolysaccharide-binding protein in some mite extracts. PMID:23640713

  9. Proteins and endotoxin in house dust mite extracts modulate cytokine secretion and gene expression by dermal fibroblasts.

    PubMed

    Rockwood, Jananie; Morgan, Marjorie S; Arlian, Larry G

    2013-11-01

    House dust mite extracts used for diagnostic tests and immunotherapy contain bioreactive molecules including proteins and endotoxin. These extracts can influence the cytokine secretion and adhesion molecule expression by cells in the skin and lung airways. The aim of this study was to determine the role of proteins and endotoxin in mite extracts in modulating gene expression and cytokine secretion by human dermal fibroblasts. Cultured normal human dermal fibroblasts were stimulated with whole mite extracts, mite extracts boiled to denature proteins, or mite extracts treated with polymyxin B to inactivate lipopolysaccharide. Gene expression and secretion of interleukin-6 (IL-6), IL-8, and monocyte chemoattractant protein-1 (MCP-1) were determined after 6 h of stimulation. Whole Dermatophagoides farinae, D. pteronyssinus and Euroglyphus maynei extracts induced dose-dependent IL-6 and IL-8 secretion. In addition, D. farinae and E. maynei induced secretion of MCP-1. Dermatophagoides farinae and E. maynei also induced parallel cytokine gene expression. Cells stimulated with boiled D. farinae extract showed moderate to marked reductions in IL-6 and IL-8 secretion. In contrast, boiled D. pteronyssinus and E. maynei extracts induced equal or greater cytokine secretions than untreated extracts. The stimulating properties were reduced for all three extracts following treatment with polymyxin B. Our data suggest that both endotoxin and proteins in mite extracts modulate the secretion of cytokines by dermal fibroblasts. The biological activities of D. farinae, D. pteronyssinus, and E. maynei extracts are not equivalent. There appears to be a lipopolysaccharide-binding protein in some mite extracts. PMID:23640713

  10. Proteolytic Activity Present in House-Dust-Mite Extracts Degrades ENA-78/CXCL5 and Reduces Neutrophil Migration

    PubMed Central

    Keglowich, Laura; Tamm, Michael; Zhong, Jun; Miglino, Nicola; Borger, Pieter

    2014-01-01

    Background. Bronchial smooth muscle cells (BSMC) are a major source of proinflammatory and proangiogenic cytokines and chemokines, including VEGF and CXC-chemokines. CXC-chemokines act primarily on neutrophils, mediating their recruitment to and activation at the site of inflammation. In humans, house-dust mite (HDM) allergens can cause asthmatic exacerbations and trigger an inflammatory response through protease-dependent mechanisms. Objective. We investigated the effect HDM extract on the release of pro-angiogenic and proinflammatory cytokines from BSMC. Methods. Human primary BSMC were stimulated with HDM extract in the absence or presence of fetal calf serum (FCS). Twenty angiogenic cytokines were detected by a specific antibody array and modified protein levels were confirmed by ELISA. Neutrophil migration was measured using a 96-well Boyden chamber. Results. ENA-78/CXCL5 protein levels in conditioned medium of BSMC stimulated with HDM extract were significantly reduced (n = 10, P < 0.05) but restored in the presence of 5% FCS. HDM extracts did not affect ENA-78/CXCL5 mRNA levels. Recombinant ENA-78/CXCL5 was degraded after incubation with HDM extracts (n = 7, P < 0.05) but restored after the addition of the serine protease AEBSF. Neutrophil migration towards recombinant ENA-78/CXCL5 was also reduced in the presence of HDM extract. Conclusion. HDM proteases degrade ENA-78/CXCL5. Thus exposure to HDM allergens may alter ENA-78/CXCL5 levels in the lungs and may affect angiogenesis and the inflammatory response in the airways of asthma patients. PMID:24883064

  11. Proteolytic Activity Present in House-Dust-Mite Extracts Degrades ENA-78/CXCL5 and Reduces Neutrophil Migration.

    PubMed

    Keglowich, Laura; Tamm, Michael; Zhong, Jun; Miglino, Nicola; Borger, Pieter

    2014-01-01

    Background. Bronchial smooth muscle cells (BSMC) are a major source of proinflammatory and proangiogenic cytokines and chemokines, including VEGF and CXC-chemokines. CXC-chemokines act primarily on neutrophils, mediating their recruitment to and activation at the site of inflammation. In humans, house-dust mite (HDM) allergens can cause asthmatic exacerbations and trigger an inflammatory response through protease-dependent mechanisms. Objective. We investigated the effect HDM extract on the release of pro-angiogenic and proinflammatory cytokines from BSMC. Methods. Human primary BSMC were stimulated with HDM extract in the absence or presence of fetal calf serum (FCS). Twenty angiogenic cytokines were detected by a specific antibody array and modified protein levels were confirmed by ELISA. Neutrophil migration was measured using a 96-well Boyden chamber. Results. ENA-78/CXCL5 protein levels in conditioned medium of BSMC stimulated with HDM extract were significantly reduced (n = 10, P < 0.05) but restored in the presence of 5% FCS. HDM extracts did not affect ENA-78/CXCL5 mRNA levels. Recombinant ENA-78/CXCL5 was degraded after incubation with HDM extracts (n = 7, P < 0.05) but restored after the addition of the serine protease AEBSF. Neutrophil migration towards recombinant ENA-78/CXCL5 was also reduced in the presence of HDM extract. Conclusion. HDM proteases degrade ENA-78/CXCL5. Thus exposure to HDM allergens may alter ENA-78/CXCL5 levels in the lungs and may affect angiogenesis and the inflammatory response in the airways of asthma patients. PMID:24883064

  12. The effects of inhaled house dust mite on airway barrier function and sensitivity to inhaled methacholine in mice.

    PubMed

    Turi, G J; Ellis, R; Wattie, J N; Labiris, N R; Inman, M D

    2011-02-01

    Asthma is functionally characterized by increased airway sensitivity and reactivity. Multiple mechanisms are believed to underlie these functional disorders, including impairment of airway wall barrier function. One proposed mechanism of impaired barrier function is through the direct consequence of proteolytic properties of inhaled allergens, including house dust mite (HDM). Here, we have observed the direct effects of HDM on airway barrier function and response to nebulized or intravenous methacholine. HDM naďve BALB/c mice were anesthetized, exposed to intranasal or intratracheal HDM (15 or 100 ?g), and allowed to recover for 30 min or 2 h before methacholine challenge. A separate group of mice was exposed to intratracheal poly-L-lysine (PLL; 100 ?g) for a duration of 30 min. This group served as a positive control for the presence of impaired barrier function and airway hypersensitivity. Negative control mice received saline challenges. Outcomes included assessment of lung mechanics in response to nebulized or intravenous methacholine as well as clearance of intratracheally instilled technetium-labeled ((99m)Tc) DTPA to evaluate airway epithelial barrier function. We found that PLL produced a leftward shift in the dose-response curve following nebulized but not intravenous methacholine challenge. This was associated with a significantly faster clearance of (99m)Tc-DTPA, indicating impairment in airway barrier function. However, HDM exposure did not produce changes in these outcomes when compared with saline-exposed mice. These findings suggest that direct impact on airway barrier function does not appear to be a mechanism by which HDM produces altered airway sensitivity in airway disease. PMID:21056959

  13. Epithelial Nuclear Factor- kappa B orchestrates house dust mite-induced airway inflammation, hyperresponsiveness, and fibrotic remodeling

    PubMed Central

    Tully, Jane E.; Hoffman, Sidra M.; Lahue, Karolyn G.; Nolin, James D.; Anathy, Vikas; Lundblad, Lennart K. A.; Daphtary, Nirav; Aliyeva, Minara; Black, Kendall E.; Dixon, Anne E.; Poynter, Matthew E.; Irvin, Charles G.; Janssen-Heininger, Yvonne M. W.

    2013-01-01

    NF-?B activation within the epithelium has been implicated in the pathogenesis of asthma, yet the exact role of epithelial NF-?B in allergen-induced inflammation and airway remodeling remains unclear. In the present study, we utilized an intranasal House Dust Mite (HDM) extract exposure regimen time course in BALB/c mice to evaluate inflammation, NF-?B activation, airway hyperresponsiveness (AHR), and airway remodeling. We utilized CC10-I?B?SR transgenic mice to evaluate the functional importance of epithelial NF-?B in response to HDM. After a single exposure of HDM, mRNA expression of pro-inflammatory mediators was significantly elevated in lung tissue of WT mice, in association with increases in nuclear RelA and RelB, components of the classical and alternative NF-?B pathway, respectively, in the bronchiolar epithelium. In contrast, CC10-I?B?SR mice displayed marked decreases in nuclear RelA and RelB and mRNA expression of pro-inflammatory mediators compared to WT mice. After 15 challenges with HDM, WT mice exhibited increases in inflammation, airway hyperresponsiveness, mucus metaplasia and peri-bronchiolar fibrosis. CC10-I?B?SR transgenic mice displayed marked decreases in neutrophilic infiltration, tissue damping, and elastance parameters, in association will less peri-bronchiolar fibrosis and decreases in nuclear RelB in lung tissue. However, central airway resistance and mucus metaplasia remained elevated in CC10-I?B?SR transgenic mice, in association with continued presence of lymphocytes, and partial decreases in eosinophils and IL-13. The current study demonstrates that following airway exposure with an asthma-relevant allergen, activation of classical and alternative NF-?B pathways occur within the airway epithelium and may coordinately contribute to allergic inflammation, AHR and fibrotic airway remodeling. PMID:24227776

  14. Addressing Lead-Based Paint Hazards During Renovation, Remodeling, and Rehabilitation in Federally Owned and Assisted Housing. Instructor Manual for Use in HUD-Sponsored Lead-Safe Work Practices Training.

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Washington, DC. Office of Pollution Prevention and Toxics.

    This document is the instructor's manual for a U.S. Department of Housing and Urban Development (HUD) training course that reflects the requirements of HUD's Lead Safe Housing Rule and is designed to provide training contractors with information regarding containment, minimization, and cleanup of lead hazards during activities that disturb…

  15. Dectin-2 promotes house dust mite-induced T helper type 2 and type 17 cell differentiation and allergic airway inflammation in mice.

    PubMed

    Norimoto, Ayako; Hirose, Koichi; Iwata, Arifumi; Tamachi, Tomohiro; Yokota, Masaya; Takahashi, Kentaro; Saijo, Shinobu; Iwakura, Yoichiro; Nakajima, Hiroshi

    2014-08-01

    The fact that sensitization against fungi is closely related to the severity of asthma suggests that immune systems recognizing fungi are involved in the pathogenesis of severe asthma. Recently, Dectin-2 (gene symbol, Clec4n), a C-type lectin receptor, has been shown to function as not only a major pattern-recognition receptor for fungi, but also a receptor for some components of house dust mite (HDM) extract, a major allergen for asthma. However, the roles of Dectin-2 in the induction of HDM-induced allergic airway inflammation remain largely unknown. Our objective was to determine the roles of Dectin-2 in HDM-induced allergic airway inflammation. We examined the roles of Dectin-2 in the induction of HDM-induced T helper (Th) 2 and Th17 cell differentiation and subsequent allergic airway inflammation by using Clec4n-deficient (Clec4n(-/-)) mice. We also investigated Dectin-2-expressing cells in the lung and their roles in HDM-induced allergic airway inflammation. Clec4n(-/-) mice showed significantly attenuated HDM-induced allergic airway inflammation and decreased Th2 and Th17 cell differentiation. Dectin-2 mRNA, together with Dectin-3 and Fc receptor-? mRNAs, was expressed in CD11b(+) dendritic cells (DCs), but not in CD4(+) T cells or epithelial cells in the lung. CD11b(+) DCs isolated from Clec4n(-/-) mice expressed lower amounts of proinflammatory cytokines and costimulatory molecules, which could lead to Th2 and Th17 cell differentiation than those from wild-type mice. HDM-pulsed Clec4n(-/-) DCs were less efficient for the induction of allergic airway inflammation than HDM-pulsed wild-type DCs. In conclusion, Dectin-2 expressed on CD11b(+) DCs promotes HDM-induced Th2 and Th17 cell differentiation and allergic airway inflammation. PMID:24588637

  16. Levels of polychlorinated biphenyls in settled house dust from urban dwellings in China and their neurodevelopmental effects on preschool-aged children.

    PubMed

    Wang, Bing-Ling; Pang, Shu-Tao; Sun, Jian-Ping; Zhang, Xiao-Ling; Li, Xi-Ling; Sun, Yong-Gang; Lu, Xiao-Mei; Zhang, Qi

    2015-02-01

    We investigated the levels of polychlorinated biphenyls (PCBs) in settled house dust (SHD) from urban dwellings with resident preschool-aged children in Nanjing, China. The possible neurodevelopmental effects of house-dust PCBs were also explored. SHD was collected from 114 urban houses. The levels of 39 PCB congeners were measured by gas chromatography-tandem mass spectrometry. The Child Behavior Checklist and the Gesell Development Inventory were used to evaluate the child's development. All 39 target congeners measured were detected. The mass percentage of di-PCBs was the highest at 47.8%, followed by tetra- and tri-PCBs at 16.8% and 13.0%, respectively. Spearman's rho correlation showed that di-, tri-, hexa-, hepta-, nona- and total PCBs were positively associated with somatic, thought problem and total problem scores (0.24

  17. Evaluation of polybrominated diphenyl ethers (PBDEs) in matched cat sera and house dust samples: investigation of a potential link between PBDEs and spontaneous feline hyperthyroidism.

    PubMed

    Chow, K; Hearn, L K; Zuber, M; Beatty, J A; Mueller, J F; Barrs, V R

    2015-01-01

    The cause of feline hyperthyroidism (FH), a common endocrinopathy of domestic cats, is unknown. A potential association between exposure to environmental contaminants polybrominated diphenyl ethers (PBDEs) and FH was investigated. The median serum level for the sum of congeners BDE-47, BDE-99, BDE-153, BDE-154 and BDE-183 (?5) in hyperthyroid and euthyroid cats was 82 and 174 ng g(-1)lw respectively with no significant difference in PBDE levels or profiles between groups. Overall, the median (min to max) concentration of PBDEs in cat serum (n=65) was 118 ng g(-1)lw (5-5260 ng g(-1)lw), which is approximately 10 times higher than that observed in the Australian human population. Furthermore, congener composition in feline serum samples was dominated by congener BDE-99, followed by BDE-47 then BDE-153 which differs from results of human biomonitoring. There was no correlation between PBDE levels in feline serum samples and matched house dust samples (n=25). However the similarity of BDE-47/99 ratio in each matrix suggests dust is likely the dominant exposure. Calculation of the daily exposure dose via dust ingestion for cats equated to a mean of 33 ng kg(-1) bw d(-1) (0.2-150 ng kg(-1) bw d(-1)). Differences in exposure estimates for Australian and US cats, based on dust ingestion alone, are consistent with the observed differences in body burdens. Our results do not support a role for PBDE exposure in the aetiopathogenesis of FH. PMID:25460634

  18. Determinants of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans in house dust samples from four areas of the United States

    PubMed Central

    NC, Deziel; Nuckols; JS, Colt; AJ, De Roos; A, Pronk; C, Gourley; RK, Severson; W, Cozen; Cerhan; P, Hartge; MH, Ward

    2012-01-01

    Determinants of levels of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/F) in dust in U.S. homes are not well characterized. We conducted a pilot study to evaluate the relationship between concentrations of PCDD/F in house dust and residential proximity to known sources, including industrial facilities and traffic. Samples from vacuum bag dust from homes of 40 residents of Detroit, Los Angeles, Seattle, or Iowa who participated in a population-based case-control study of non-Hodgkin lymphoma conducted in 1998–2000 were analyzed using high resolution gas chromatography/high resolution mass spectrometry for 7 PCDD and 10 PCDF congeners considered toxic by the U.S. Environmental Protection Agency (EPA). Locations of 10 types of PCDD/F-emitting facilities were obtained from the EPA; however only 4 types were located near study homes (non-hazardous waste cement kilns, coal-fired power plants, sewage sludge incinerators, and medical waste incinerators). Relationships between concentrations of each PCDD/F and proximity to industrial facilities, freight routes, and major roads were evaluated using separate multivariate regression models for each congener. The median (inter-quartile range [IQR]) toxic equivalence (TEQ) concentration of these congeners in the house dust was 20.3 pg/g (IQR=14.3, 32.7). Homes within 3 or 5 km of a cement kiln had 2 to 9-fold higher concentrations of 5 PCDD and 5 PCDF (p<0.1 in each model). Proximity to freight routes and major roads was associated with elevated concentrations of 1 PCDD and 8 PCDF. Higher concentrations of certain PCDD/F in homes near cement kilns, freight routes, and major roads suggest these outdoor sources are contributing to indoor environmental exposures. Further study of the contribution of these sources and other facility types to total PCDD/F exposure in a larger number of homes is warranted. PMID:22832089

  19. Impact of dust filter installation in ironworks and construction on brownfield area on the toxic metal concentration in street and house dust (Celje, Slovenia).

    PubMed

    Zibret, Gorazd

    2012-05-01

    This article presents the impact of the ecological investment in ironworks (dust filter installation) and construction works at a highly contaminated brownfield site on the chemical composition of household dust (HD) and street sediment (SS) in Celje, Slovenia. The evaluation is based on two sampling campaigns: the first was undertaken 1 month before the ecological investment became operational and the second 3 years later. The results show that dust filter installations reduced the content of Co, Cr, Fe, Mn, Mo, W and Zn on average by 58% in HD and by 51% in SS. No reduction was observed at sampling points in the upwind direction from the ironworks. By contrast, the impact of the construction works on the highly contaminated brownfield site was detected by a significant increase (on average by 37%) of elements connected to the brownfield contamination in SS. Such increase was not detected in HD. PMID:22535428

  20. Safety, tolerability, and impact on allergic inflammation of autologous E.coli autovaccine in the treatment of house dust mite asthma - a prospective open clinical trial

    Microsoft Academic Search

    Markus A Rose; Bianca Weigand; Ralf Schubert; Johannes Schulze; Stefan Zielen

    2011-01-01

    Background  Asthma is increasing worldwide and results from a complex immunological interaction between genetic susceptibility and environmental\\u000a factors. Autovaccination with E. coli induces a strong TH-1 immune response, thus offering an option for the treatment of allergic diseases.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  Prospective open trial on safety, tolerability, and impact on allergic inflammation of an autologous E.coli autovaccine in intermittent or mild persistent house dust

  1. The relationship of environmental lead to blood-lead levels in children

    Microsoft Academic Search

    A. D. Stark; R. Quah; J. W. Meigs; E. R. DeLouise

    1982-01-01

    An in-depth study of the distribution of lead sources in the residential environment of 377 children in New Haven, Connecticut, was carried out. Substantial amounts of lead were present in soil, paint, and house dust throughout New Haven, but not in air or water. Multiple regression modeling indicated that the most important contributors to variation in children's blood-lead levels were

  2. INVESTIGATION OF THE DECLINE OF THE NUMBER OF HOUSING UNITS WITH LEAD-BASED PAINT - DISCONTINUED DUE TO LACK OF FUNDS

    EPA Science Inventory

    This project was discontinued on October 1, 2004 due to lack of funds. The product of this activity was a draft report that investigated the decline in the number of housing units with lead-based paint. In the early 1990s, the US Department of Housing and Urban Development (H...

  3. Removal of lead by using Raschig rings manufactured with mixture of cement kiln dust, zeolite and bentonite.

    PubMed

    Salem, A; Afshin, H; Behsaz, H

    2012-07-15

    The present investigation is a follow-up of study on manufacturing Raschig ring for removal of lead from aqueous solution. The mixtures were formulated using cement kiln dust, zeolite, and bentonite, normally used as natural adsorbents in the industrial scale, according to mixture design algorithm and response surface method. The pastes were prepared by addition of 28.0wt.% de-ionized water, containing 0.1wt.% carboxymethyl cellulose, with mixed powders. The adsorbents were fabricated by extrusion of the pastes in Raschig ring form and calcination at 500°C after drying in oven. The effects of starting materials on the mechanical behavior of rings were studied from view point of mixture design algorithm to optimize the adsorbent composition. This method demonstrated to yield valuable information on the effects of used materials on mechanical characteristics. The study concluded that the strength, reliability and sorption capacity of ring can be simultaneously optimized by the addition of 47.5wt.% cement kiln dust, 32.5wt.% zeolite, and 20.0wt.% bentonite. In the next part of work, the sorption kinetics was investigated. The kinetic study indicated that the modified model can successfully correlate the sorption data. The equilibrium result showed the possibility of lead immobilization by fabricated rings. PMID:22608209

  4. House dust mite potentiates capsaicin-evoked Ca2+ transients in mouse pulmonary sensory neurons via activation of protease-activated receptor-2

    PubMed Central

    Gu, Qihai; Lee, Lu-Yuan

    2011-01-01

    House dust mite (HDM) is a major source of allergen in house dust and has been suggested to be involved in the pathogenesis of asthma. In this study, we aimed to investigate whether HDM can modulate the sensitivity of pulmonary sensory neurons, and if so, to elucidate the underlying mechanism. Fura-2 based ratiometric Ca2+ imaging was carried out to determine the effect of HDM extract on the capsaicin-evoked Ca2+ transient in mouse vagal pulmonary sensory neurons. Pretreatment with HDM (50 ?g/ml, 5 min) significantly enhanced the Ca2+ transient evoked by capsaicin in these neurons isolated from wildtype mice. This potentiating effect of HDM was not antagonized by E-64, a selective cysteine protease inhibitor, but was completely prevented by AEBSF, a specific serine protease inhibitor. In addition, the potentiating effect of HDM on capsaicin-evoked Ca2+ transient was absent in the pulmonary sensory neurons isolated from protease-activated receptor-2 (PAR2) knockout mice. Further, the sensitizing effect of HDM was completely abolished by U73122, a PLC inhibitor, or chelerythrine, a PKC inhibitor. In summary, our results demonstrate that HDM, mainly through its serine protease activity, potentiates capsaicin-evoked Ca2+ transient in mouse pulmonary sensory neurons via the activation of PAR2 and PLC-PKC intracellular transduction cascade. PMID:22125310

  5. 42 CFR 84.1146 - Lead fume test for dust, fume, and mist respirators; minimum requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...and Mist; Pesticide; Paint Spray; Powered Air-Purifying High Efficiency Respirators and Combination Gas Masks § 84.1146...than 15 nor more than 20 milligrams of freshly generated lead-oxide fume, calculated as lead (Pb), per cubic meter of...

  6. 42 CFR 84.1146 - Lead fume test for dust, fume, and mist respirators; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...and Mist; Pesticide; Paint Spray; Powered Air-Purifying High Efficiency Respirators and Combination Gas Masks § 84.1146...than 15 nor more than 20 milligrams of freshly generated lead-oxide fume, calculated as lead (Pb), per cubic meter of...

  7. 42 CFR 84.1146 - Lead fume test for dust, fume, and mist respirators; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...and Mist; Pesticide; Paint Spray; Powered Air-Purifying High Efficiency Respirators and Combination Gas Masks § 84.1146...than 15 nor more than 20 milligrams of freshly generated lead-oxide fume, calculated as lead (Pb), per cubic meter of...

  8. 42 CFR 84.1146 - Lead fume test for dust, fume, and mist respirators; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...and Mist; Pesticide; Paint Spray; Powered Air-Purifying High Efficiency Respirators and Combination Gas Masks § 84.1146...than 15 nor more than 20 milligrams of freshly generated lead-oxide fume, calculated as lead (Pb), per cubic meter of...

  9. 42 CFR 84.1146 - Lead fume test for dust, fume, and mist respirators; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...and Mist; Pesticide; Paint Spray; Powered Air-Purifying High Efficiency Respirators and Combination Gas Masks § 84.1146...than 15 nor more than 20 milligrams of freshly generated lead-oxide fume, calculated as lead (Pb), per cubic meter of...

  10. Environmental Isolation of Cryptococcus gattii VGII from Indoor Dust from Typical Wooden Houses in the Deep Amazonas of the Rio Negro Basin

    PubMed Central

    Brito-Santos, Fábio; Barbosa, Gláucia Gonçalves; Trilles, Luciana; Nishikawa, Marília Martins; Wanke, Bodo; Meyer, Wieland; Carvalho-Costa, Filipe Anibal; Lazéra, Márcia dos Santos

    2015-01-01

    Cryptococcosis is a human fungal infection of significant mortality and morbidity, especially in the meningoencephalitis form. Cryptococcosis is distributed worldwide and its agents, C. neoformans and C. gattii, present eight major molecular types—VNI-VNIV and VGI-VGIV respectively. The primary cryptococcosis caused by molecular type VGII (serotype B, MAT alpha) prevails in immunocompetent patients in the North and Northeast of Brazil, revealing an endemic regional pattern to this molecular type. Since 1999, C. gattii VGII has been involved in an ongoing outbreak in Canada, and is expanding to the Northwest of the United States, two temperate regions. Exposure to propagules dispersed in the environment, related to various organic substrates, mainly decomposing wood in and around dwellings, initiates the infection process. The present study investigated the presence of the agents of cryptococcosis in dust from dwellings in the upper Rio Negro, municipality of Santa Isabel do Rio Negro in Amazonas state. Indoor dust was collected from 51 houses, diluted and plated on bird seed agar. Dark brown colonies were identified phenotypically, and genotypically by URA5 restriction fragment length polymorphism analysis and multilocus sequence typing (MLST). The mating type was identified using pheromone-specific primers. Three of the 51 houses were positive for C. gattii molecular type VGII, MAT? and MATa, showing a high prevalence of this agent. MLST studies identified eight subtypes, VGIIb (ST7), VGIIa (ST20), (ST5) and 5 new subtypes unique to the region. For the first time in the state of Amazonas, C. gattii VGII MAT? and MATa were isolated from the environment and correlates with endemic cryptococcosis in this state. This is the first description of MLST subtypes on environmental isolates in the Brazilian Amazon, indicating domiciliary dust as a potential source for human infection with different subtypes of C. gattii VGII MAT? and MATa. PMID:25688971

  11. Large-scale production of major house dust mite allergen der f 2 mutant (C8/119S) in Escherichia coli.

    PubMed

    Koyanagi, Satoshi; Maeda, Toshihiro; Murakami, Toshio; Kawatsu, Kenjirou; Sugawara, Keishin; Miyatsu, Yoshinobu; Mizokami, Hiroshi

    2008-10-01

    Hyposensitization, in which causative antigens of allergic diseases are injected, is the sole means of a radical cure for allergic diseases. Since the therapeutic allergens currently used are naturally extracted, producing preparations with a stable titer from such extracts is extremely difficult. There are several reports on the expression of recombinant mite allergens in Escherichia coli using inducers. The use of an inducer for industrial production will lead to high costs and, for therapeutic use, it must be removed in the purification process. C8/119S is a mutant of Der f 2, a major house dust mite allergen. The C8/119S gene was integrated downstream of the trp promoter to produce the expression plasmid (pWU11-C8/119S). Then, this expression plasmid was used to transform E. coli strain HB101 (pWU11-C8/119S/HB101). A recombinant E. coli pWU11-C8/119S/HB101 did not express C8/119S in a low-temperature culture (32 degrees C), but C8/119S was induced to a high level of expression in a high-temperature culture (37 degrees C). pWU11-C8/119S/HB101 proliferated when expression was induced by high temperature and an approximately 3-fold greater proliferation was obtained compared with the use of an inducer in a large-scale culture. The C8/119S protein was expressed as inclusion bodies and obtained by refolding and chromatography purifications. The immunological properties of C8/119S were assessed by western blotting. Western blotting demonstrated that purified C8/119S reacted with a monoclonal anti-Der f 2 antibody (18G8). pWU11-C8/119S/HB101 can be used as an easy, low cost expression system on a large scale. It is also advantageous for industrial production in that the addition of an inducer is not required to achieve expression of the mite allergen. PMID:19000616

  12. Sources of halogenated brominated retardants in house dust in an industrial city in southern China and associated human exposure.

    PubMed

    Chen, She-Jun; Ding, Nan; Zhu, Zhi-Cheng; Tian, Mi; Luo, Xiao-Jun; Mai, Bi-Xian

    2014-11-01

    Halogenated flame retardants (HFRs) are a class of ubiquitous pollutants in the environment and attract increasing attention. In the present study, HFR concentrations were measured in indoor and outdoor dust in an important industrial city (Dongguan) in southern China, in which their presence and associated human exposure are unknown. The HFRs were dominated by polybrominated diphenyl ethers (PBDEs) and decabromodiphenyl ethane (DBDPE), with mean concentrations of 2365 and 2441 ng/g in the indoor dust, respectively, which were 2-3 order of magnitude higher the concentrations of other HFRs. However elevated tri- to hepta-BDE concentrations (869 ng/g) were found in Houjie Town, a furniture manufacturing center. The mean indoor/outdoor (I/O) ratios of HFR concentrations in the dust were all larger than one (1.55-16.4), suggesting the importance of indoors sources for HFRs in indoor dust in this industrial city. Principal component analysis (PCA) showed that the correlations among the HFRs in the indoor dust probably revealed differences in their commercial applications, while most HFRs in the outdoor dust have similar sources except for phased-out BDE47 and 99. The compositions of lower brominated PBDEs varied among the towns, probably due to their different sources or influence of photo-degradation. Nevertheless, the similar composition of highly brominated congeners indicated little photo-degradation encountered in the ambient environment. The non-cancer risk associated with indoor dust ingestion is low for the general population in Dongguan, but some children in the furniture manufacturing center have significantly high risk of exposure to banned PBDEs. PMID:25282276

  13. Exposures to Lead-Based Paint Dust in an Inner-City High School

    Microsoft Academic Search

    John A. Decker; Robert Malkin; Max Kiefer

    1999-01-01

    In response to concerns about lead-based paint (LBP) in an 85-year old high school, an evaluation was conducted to determine whether a lead exposure hazard existed for adult school staff. Deteriorating LBP was present on walls and ceilings throughout the school. At the time of the evaluation, abatement of LBP had been completed in approximately one-third of the school. One-hundred

  14. ELEVATED LEAD LEVELS IN URBAN HOUSE SPARROWS: A THREAT TO SHARP-SHINNED HAWKS AND MERLINS?

    Microsoft Academic Search

    RICHARD B. CHANDLER; ALLAN M. STRONG; CARLIN C. KAUFMAN

    ABSTRAGT.--In urban environments, lead (Pb) has been recognized as a health threat to humans as well as wildlife. Although this hazard has waned since the banning of leaded gasoline and paint in the 1970s, soil and atmospheric Pb concentrations have remained higher in disturbed habitats than in exurban habitats. Our study evaluated the threat of Pb exposure to Sharp-shinned Hawks

  15. INVESTIGATION OF LEAD TEST KITS FOR ANALYSIS OF PAINT, DUST, AND SOIL

    EPA Science Inventory

    A study of commercial lead test kits available as of fall, 1990, was performed. he intent was to perform an initial study of the general behavior and responsiveness of all kits to the same but limited number of test parameters and materials. he manufacturers' instructions provide...

  16. DEVELOPMENT AND EVALUATION OF MONITORING METHODS FOR POLYCYCLIC AROMATIC HYDROCARBONS IN HOUSE DUST AND TRACK-IN SOIL

    EPA Science Inventory

    The analytical methods were developed for the determination of PAH and PCBs in the dust and soil based on sonication with hexane and 10% ether/hexane, respectively, and analysis by gas chromatography/mass spectrometry (GC/MS). uantitative recoveries of spiked perdeuterated PAH an...

  17. Anaphylaxis following the ingestion of flour contaminated by house dust mites--a report of two cases from Singapore.

    PubMed

    Tay, S Y; Yan, Tay Sok; Tham, E; Elizabeth, Tham; Yeo, C T; Tzien, Yeo Chor; Yi, F C; Cheng, Yi Fong; Chen, J Y; Jiayi, Chen; Cheong, N; Nge, Cheong; Chua, K Y; Yan, Chua Kaw; Lee, B W; Wah, Lee Bee

    2008-01-01

    This study presents two patients who developed anaphylaxis after eating mite-contaminated food, and also contains a survey of dust-mites contamination in flour samples from Singapore households. The clinical records of each patient was studied. Patient A developed anaphylaxis twenty minutes following the ingestion of home-made fried fish coated with Japanese flour, while Patient B developed similar life-threatening symptoms one hour after the ingestion of home baked scones. Both patients were NSAID-intolerant and had a history of allergic rhinitis. Skin prick tests showed a strong positive result for dust-mites and for extracts prepared from the ingested flour. Flour samples were also examined microscopically which revealed large numbers of live Dermatophagoides farinae dust-mites. A survey of 57 flour samples showed that 4 samples (7%) were contaminated with dust mites. The findings in the present study confirm that mite-contamination of flour exists in Singaporean households, and it may trigger anaphylaxis in susceptible individuals. PMID:19054935

  18. CDC Recommendations for Lead Poisoning Prevention in Newly Arrived Refugee Children

    E-print Network

    for elevated BLLs because of their frequent exposure to lead-based paint and lead-contaminated house dustCDC Recommendations for Lead Poisoning Prevention in Newly Arrived Refugee Children Lead the United States (US) has made great strides in reducing the number of children with elevated blood lead

  19. Life in cellulose houses: Symbiotic bacterial biosynthesis of ascidian drugs and drug leads

    PubMed Central

    Schmidt, Eric W.; Donia, Mohamed S.

    2010-01-01

    Ascidians (tunicates; sea squirts) are sources of diverse, bioactive natural products, one of which is an approved drug and many of which are potent drug leads. It has been shown that symbiotic bacteria living with ascidians produce some of the bioactive compounds isolated from whole animals, and indirect evidence strongly implicates symbiotic bacteria in the synthesis of many others. However, for the majority the producing organism has not been identified. In cases where a symbiotic origin has been definitively assigned, the resulting data lead to improved paths to drug discovery and development from marine animals. This review traces evidence for symbiotic production where such evidence exists and describes the strengths and limitations of that evidence. PMID:21050742

  20. A novel in situ method for sampling urban soil dust: particle size distribution, trace metal concentrations, and stable lead isotopes.

    PubMed

    Bi, Xiangyang; Liang, Siyuan; Li, Xiangdong

    2013-06-01

    In this study, a novel in situ sampling method was utilized to investigate the concentrations of trace metals and Pb isotope compositions among different particle size fractions in soil dust, bulk surface soil, and corresponding road dust samples collected within an urban environment. The aim of the current study was to evaluate the feasibility of using soil dust samples to determine trace metal contamination and potential risks in urban areas in comparison with related bulk surface soil and road dust. The results of total metal loadings and Pb isotope ratios revealed that soil dust is more sensitive than bulk surface soil to anthropogenic contamination in urban areas. The new in situ method is effective at collecting different particle size fractions of soil dust from the surface of urban soils, and that soil dust is a critical indicator of anthropogenic contamination and potential human exposure in urban settings. PMID:23466731

  1. Eosinophil Count in Nasal Mucosa Is More Suitable than the Number of ICAM-1Positive Nasal Epithelial Cells to Evaluate the Severity of House Dust Mite-Sensitive Allergic Rhinitis: A Clinical Correlation Study

    Microsoft Academic Search

    Jettanong Klaewsongkram; Kiat Ruxrungtham; Pongsak Wannakrairot; Preecha Ruangvejvorachai; Praphan Phanupak

    2003-01-01

    Background: House dust mite (HDM)-sensitive allergic rhinitis is a perennial rhinitis with persistent nasal inflammation. Currently, there are no reliable parameters to monitor the severity of perennial allergic rhinitis. The purpose of this study was to evaluate correlations between clinical and laboratory parameters in patients with HDM-sensitive allergic rhinitis. Methods: We measured nasal symptoms, did the Dermatophagoides pteronyssinus (Der P)

  2. 1 http://www.e1.greatlakes.com/fr/products/jsp/firemaster_550.jsp. 2 Stapleton et al.2008.Alternate and New Brominated Flame Retardants Detected in US House Dust.

    E-print Network

    .2008.Alternate and New Brominated Flame Retardants Detected in US House Dust. 10th Annual Workshop on Brominated Flame Retardants,Victoria,BC,Canada. 3 Andersson,P.L.; Oberg,K.; Orn,U.,2006.Chemical characterization of brominated flame retardants and identification of structurally representative compounds

  3. Effectiveness of omalizumab in a patient with a life-threatening episode of bronchospasm and larynx angioedema after exposure to house dust.

    PubMed

    Kupry?-Lipi?ska, Izabela; Korczy?ska, Paulina; Tworek, Damian; Kuna, Piotr

    2014-02-01

    Omalizumab is a monoclonal antibody against IgE, nowadays approved for the treatment of persistent severe (EU) or moderate-to severe (USA) IgE-mediated asthma but there is also some evidence (case reports and four published clinical trials) on the effectiveness of this medication in urticaria and angioedema. The case of a 42-year-old woman suffering from severe allergic asthma and severe chronic urticaria with concomitant angioedema is presented in the article. She had a life-threatening episode of bronchospasm and larynx edema after exposure to house dust recorded in her medical history. The patient did not respond to standard therapy. The improvement in asthma control and remission of chronic urticaria and angioedema was achieved after introducing the therapy with omalizumab. PMID:24683397

  4. The Discovery of Potent, Selective, and Reversible Inhibitors of the House Dust Mite Peptidase Allergen Der p 1: An Innovative Approach to the Treatment of Allergic Asthma

    PubMed Central

    2014-01-01

    Blocking the bioactivity of allergens is conceptually attractive as a small-molecule therapy for allergic diseases but has not been attempted previously. Group 1 allergens of house dust mites (HDM) are meaningful targets in this quest because they are globally prevalent and clinically important triggers of allergic asthma. Group 1 HDM allergens are cysteine peptidases whose proteolytic activity triggers essential steps in the allergy cascade. Using the HDM allergen Der p 1 as an archetype for structure-based drug discovery, we have identified a series of novel, reversible inhibitors. Potency and selectivity were manipulated by optimizing drug interactions with enzyme binding pockets, while variation of terminal groups conferred the physicochemical and pharmacokinetic attributes required for inhaled delivery. Studies in animals challenged with the gamut of HDM allergens showed an attenuation of allergic responses by targeting just a single component, namely, Der p 1. Our findings suggest that these inhibitors may be used as novel therapies for allergic asthma. PMID:25365789

  5. Effectiveness of omalizumab in a patient with a life-threatening episode of bronchospasm and larynx angioedema after exposure to house dust

    PubMed Central

    Korczy?ska, Paulina; Tworek, Damian; Kuna, Piotr

    2014-01-01

    Omalizumab is a monoclonal antibody against IgE, nowadays approved for the treatment of persistent severe (EU) or moderate-to severe (USA) IgE-mediated asthma but there is also some evidence (case reports and four published clinical trials) on the effectiveness of this medication in urticaria and angioedema. The case of a 42-year-old woman suffering from severe allergic asthma and severe chronic urticaria with concomitant angioedema is presented in the article. She had a life-threatening episode of bronchospasm and larynx edema after exposure to house dust recorded in her medical history. The patient did not respond to standard therapy. The improvement in asthma control and remission of chronic urticaria and angioedema was achieved after introducing the therapy with omalizumab. PMID:24683397

  6. Neutralisation of Interleukin13 in Mice Prevents Airway Pathology Caused by Chronic Exposure to House Dust Mite

    Microsoft Academic Search

    Kate L. Tomlinson; Gareth C. G. Davies; Daniel J. Sutton; Roger T. Palframan

    2010-01-01

    BackgroundRepeated exposure to inhaled allergen can cause airway inflammation, remodeling and dysfunction that manifests as the symptoms of allergic asthma. We have investigated the role of the cytokine interleukin-13 (IL-13) in the generation and persistence of airway cellular inflammation, bronchial remodeling and deterioration in airway function in a model of allergic asthma caused by chronic exposure to the aeroallergen House

  7. Major house dust mite allergens Dermatophagoides pteronyssinus 1 and Dermatophagoides farinae 1 degrade and inactivate lung surfactant proteins A and D.

    PubMed

    Deb, Roona; Shakib, Farouk; Reid, Kenneth; Clark, Howard

    2007-12-21

    Lung surfactant proteins (SP) A and D are calcium-dependent carbohydrate-binding proteins. In addition to playing multiple roles in innate immune defense such as bacterial aggregation and modulation of leukocyte function, SP-A and SP-D have also been implicated in the allergic response. They interact with a wide range of inhaled allergens, competing with their binding to cell-sequestered IgE resulting in inhibition of mast cell degranulation, and exogenous administration of SP-A and SP-D diminishes allergic hypersensitivity in vivo. House dust mite allergens are a major cause of allergic asthma in the western world, and here we confirm the interaction of SP-A and SP-D with two major mite allergens, Dermatophagoides pteronyssinus 1 and Dermatophagoides farinae 1, and show that the cysteine protease activity of these allergens results in the degradation of SP-A and SP-D under physiological conditions, with multiple sites of cleavage. A recombinant fragment of SP-D that is effective in diminishing allergic hypersensitivity in mouse models of dust mite allergy was more susceptible to degradation than the native full-length protein. Degradation was enhanced in the absence of calcium, with different sites of cleavage, indicating that the calcium associated with SP-A and SP-D influences accessibility to the allergens. Degradation of SP-A and SP-D was associated with diminished binding to carbohydrates and to D. pteronyssinus 1 itself and diminished capacity to agglutinate bacteria. Thus, the degradation and consequent inactivation of SP-A and SP-D may be a novel mechanism to account for the potent allergenicity of these common dust mite allergens. PMID:17848554

  8. PREPARATION OF LEAD-CONTAINING PAINT AND DUST METHOD EVALUATION MATERIALS AND VERIFICATION OF THE PREPARATION PROTOCOL BY ROUND-ROBIN ANALYSIS

    EPA Science Inventory

    Protocols for preparing method evaluation materials from real-world lead-containing paints and dusts were developed. he materials were evaluated in a round-robin using five combinations of extraction methods/quantitation techniques (hot-plate and microwave extractions/atomic abso...

  9. Quantification of ergosterol and 3-hydroxy fatty acids in settled house dust by gas chromatography-mass spectrometry: comparison with fungal culture and determination of endotoxin by a Limulus amebocyte lysate assay.

    PubMed Central

    Saraf, A; Larsson, L; Burge, H; Milton, D

    1997-01-01

    Ergosterol and 3-hydroxy fatty acids, chemical markers for fungal biomass and the endotoxin of gram-negative bacteria, respectively, may be useful in studies of health effects of organic dusts, including domestic house dust. This paper reports a method for the combined determination of ergosterol and 3-hydroxy fatty acids in a single dust sample and a comparison of these chemical biomarkers determined by gas chromatography-mass spectrometry with results from fungal culture and Limulus assay. Analyses of replicate house dust samples resulted in correlations of 0.91 (ergosterol in six replicates; P < 0.01) and 0.94 (3-hydroxy fatty acids in nine replicates; P < 0.001). The amounts of ergosterol (range, 2 to 16.5 ng/mg of dust) correlated with those of total culturable fungi (range, 6 to 1,400 CFU/mg of dust) in 17 samples, (r = 0.65; P < 0.005). The amounts of endotoxin (range, 11 to 243 endotoxin units/mg of dust) measured with a modified chromogenic Limulus assay correlated with those of lipopolysaccharide (LPS) determined from 3-hydroxy fatty acid analysis of 15 samples. The correlation coefficient depended on the chain lengths of 3-hydroxy acids used to compute the LPS content. The correlation was high (r = 0.88 +/- 0.01; P < 0.001) when fatty acid chains of 10 to 14 carbon atoms were included; the correlation was much lower when hydroxy acids of 16- or 18-carbon chains were included. In conclusion, the results of the described extraction and analysis procedure for ergosterol and 3-hydroxy fatty acids are reproducible, and the results can be correlated with fungal culture and endotoxin activity of organic dust samples. PMID:9212406

  10. Lead

    MedlinePLUS

    ... lead-based paint chips or playing in contaminated soil. Lead can damage the nervous system, kidneys, and ... settling to the ground. • Once lead falls onto soil, it usually sticks to soil particles. • Movement of ...

  11. H. R. 527: A Bill to authorize research and evaluation programs for monitoring, detecting, and abating lead based paint and other lead exposure hazards in housing, and for other purposes, introduced in the House of Representatives, One Hundred Second Congress, First Session, January 14, 1991

    SciTech Connect

    Not Available

    1991-01-01

    Lead poses a significant environmental health problem since adverse effects have been conclusively demonstrated at relatively low exposures. H.R.527 was introduced into the US House of Representatives on January 14 1991 to authorize research and evaluation programs for monitoring, detecting, and abating lead based paint and other lead exposure hazards in housing. Attention is focused on the following: laboratory analysis standardization; detection technologies; research on abatement and in-place management techniques; abatement products; lead exposure in children; public education; and authorization of appropriations.

  12. Lead Sampling Technician Training Course. Trainer Manual.

    ERIC Educational Resources Information Center

    ICF, Inc., Washington, DC.

    This document presents a model curriculum for use by trainers presenting training course in assessing and reporting dust and debris from deteriorated lead-based paint. The course, which was developed by the U.S. Environmental Protection Agency, is intended for use with housing quality standard inspectors, rehabilitation specialists, home…

  13. Comparison of home lead dust reduction techniques on hard surfaces: the New Jersey assessment of cleaning techniques trial.

    PubMed

    Rich, David Q; Rhoads, George G; Yiin, Lih-Ming; Zhang, Junfeng; Bai, Zhipeng; Adgate, John L; Ashley, Peter J; Lioy, Paul J

    2002-09-01

    High efficiency particulate air filter (HEPA) vacuums, which collect particles > 0.3 micro m, and trisodium phosphate (TSP), a detergent claimed to selectively remove lead, have been included in the HUD Guidelines for the Evaluation and Control of Lead Based Paint Hazards in Housing without systematic validation of their effectiveness. At the time the study was initiated, both HEPA vacuums and TSP were relatively expensive, they were not readily found in urban retail centers, and there were environmental concerns about the use and disposal of high-phosphate detergents. A randomized, controlled trial was conducted in urban high-risk homes in northern New Jersey to determine whether a more readily available and less expensive low-phosphate, non-TSP detergent and non-HEPA vacuum could perform as well as TSP and a HEPA vacuum in a cleaning protocol. Homes were randomized to one of three cleaning methods: TSP/HEPA vacuum, TSP/non-HEPA vacuum, or non-TSP/non-HEPA vacuum. Change in log-transformed lead loading was used in mixed models to compare the efficacy of the three cleaning techniques separately for uncarpeted floors, window sills, and window troughs. After we adjusted for baseline lead loading, the non-HEPA vacuum produced larger reductions on hard floors [19%; 95% confidence interval (CI), 3-38%], but the HEPA vacuum produced larger reductions on window sills (22%; 95% CI, 11-32%) and larger reductions on window troughs (16%; 95% CI, -4 to 33%). The non-TSP produced larger reductions on window troughs (21%; 95% CI, -2 to 50%), but TSP produced larger reductions on hard floors (5%; 95% CI, -12 to 19%) and window sills (8%; 95% CI, -5 to 20%). TSP/HEPA produced larger reductions on window sills (28%; 95% CI, 18-37%) and larger reductions on window troughs (2%; 95% CI, -24 to 23%), whereas the non-TSP/non-HEPA method produced larger reductions on hard floors (13%; 95% CI, -5 to 34%). Because neither vacuum nor detergent produced consistent results across surface types, the use of low-phosphate detergents and non-HEPA vacuums in a temporary control measure is supported. PMID:12204823

  14. Associations of allergic sensitization and clinical phenotypes with innate immune response genes polymorphisms are modified by house dust mite allergen exposure

    PubMed Central

    Kurowski, Marcin; Majkowska-Wojciechowska, Barbara; Wardzy?ska, Aleksandra

    2011-01-01

    Introduction Polymorphisms within innate immunity genes are associated with allergic phenotypes but results are variable. These associations were not analyzed with respect to allergen exposure. We investigated associations of TLR and CD14 polymorphisms with allergy phenotypes in the context of house dust mite (HDM) exposure. Material and methods Children, aged 12-16 years (n=326), were recruited from downtown and rural locations and assessed by allergist. Skin prick tests, total and HDM-specific sIgE measurements were done. HDM allergen concentrations in dust were measured. Genetic polymorphisms were identified using restriction fragment length polymorphism (RFLP). Results Allergic rhinitis, asthma and atopy were more prevalent in urban area. Although HDM allergen concentrations were higher in rural households, sIgE were present more frequently in urban children. In the whole population no association was found between HDM exposure and sensitization. In children with CD14/?159CC, CD14/?159TT and TLR9/2848GA genotypes increased exposure to HDM was associated with reduced incidence of allergic rhinitis. Significant associations of increased HDM exposure with reduced incidence of atopy were found for the whole population and subjects with CD14/?159CC, CD14/?1359GT, TLR4/896AA and TLR9/2848GA genotypes. Among children with CD14/?159CC and CD14/?1359GG significant positive correlation between HDM allergen concentrations in household and sensitization to HDM was observed. In contrast, protective effect of high HDM allergen exposure against specific sensitization was seen in subjects with TLR4/896 AG. Conclusions Development of specific sensitization and allergy may be associated with innate immune response genes polymorphisms and is modified by allergen exposure. PMID:22328887

  15. Lead Poisoning

    MedlinePLUS

    ... contaminated by lead (whether that lead is from gasoline emissions or from deteriorated house paint) can end up ... contain some lead, either deposited there by vehicle emissions from leaded gasoline days, or from deteriorated exterior paint. This is ...

  16. Production of a mouse\\/human chimeric IgE monoclonal antibody to the house dust mite allergen Der p 2 and its use for the absolute quantification of allergen-specific IgE

    Microsoft Academic Search

    Janine Schuurman; Gerrard J. Perdok; Tom E. Lourens; Paul W. H. I. Parren; Martin D. Chapman; Rob C. Aalberse

    1997-01-01

    A chimeric human IgE monoclonal antibody was developed against the house dust mite allergen Der p 2. This chimeric antibody (hIgE-Dp2A) was composed of the heavy-chain variable domains and light chains of the original murine monoclonal antibody retaining its binding characteristics, whereas the heavy-chain constant domains were exchanged with the human IgE heavy chain. The chimeric IgE expression level was

  17. Identification of lead sources in residential environments: Sydney Australia.

    PubMed

    Laidlaw, M A S; Zahran, S; Pingitore, N; Clague, J; Devlin, G; Taylor, M P

    2014-01-01

    Interior and exterior dust, soil and paint were analysed at five brick urban Sydney homes over 15 months to evaluate temporal variations and discriminate sources of lead (Pb) exposure. Exterior dust gauge Pb loading rates (?g/m(2)/28 days), interior vacuum dust Pb concentrations (mg/kg) and interior petri-dish Pb loading rates (?g/m(2)/28 days), were correlated positively with soil Pb concentrations. Exterior dust gauge Pb loading rates and interior vacuum dust Pb concentrations peaked in the summer. Lead isotope and Pb speciation (XAS) were analysed in soil and vacuum dust samples from three of the five houses that had elevated Pb concentrations. Results show that the source of interior dust lead was primarily from soil in two of the three houses and from soil and Pb paint in the third home. IEUBK child blood Pb modelling predicts that children's blood Pb levels could exceed 5 ?g/dL in two of the five houses. PMID:24071634

  18. Crystallization and preliminary X-ray analysis of Der f 2, a potent allergen derived from the house dust mite (Dermatophagoides farinae)

    NASA Technical Reports Server (NTRS)

    Roeber, Dana; Achari, Aniruddha; Takai, Toshiro; Okumura, Yasushi; Scott, David L.

    2003-01-01

    Although a number of allergens have been identified and isolated, the underlying molecular basis for the potent immune response is poorly understood. House dust mites (Dermatophagoides sp.) are ubiquitous contributors to atopy in developed countries. The rhinitis, dermatitis and asthma associated with allergic reactions to these arthropods are frequently caused by relatively small (125-129 amino acids) mite proteins of unknown biological function. Der f 2, a major allergen from the mite D. farinae, has been recombinantly expressed, characterized and crystallized. The crystals belong to the tetragonal space group I4(1)22, with unit-cell parameters a = b = 95.2, c = 103.3 A. An essentially complete (97.2%) data set has been collected to 2.4 A at a synchrotron source. Attempts to solve the crystal structure of Der f 2 by molecular replacement using the NMR coordinates for either Der f 2 or Der p 2 (the homologous protein from D. pteronyssinus) failed, but preliminary searches using the crystalline Der p 2 atomic coordinates appear to be promising.

  19. Application of the Phylogenetic Species Concept to Wallemia sebi from House Dust and Indoor Air Revealed by Multi-Locus Genealogical Concordance

    PubMed Central

    Nguyen, Hai D. T.; Jan?i?, Sašo; Meijer, Martin; Tanney, Joey B.; Zalar, Polona; Gunde-Cimerman, Nina; Seifert, Keith A.

    2015-01-01

    A worldwide survey of Wallemia occurring in house dust and indoor air was conducted. The isolated strains were identified as W. sebi and W. muriae. Previous studies suggested that the W. sebi phylogenetic clade contained cryptic species but conclusive evidence was lacking because only the internal transcribed spacer (ITS) marker was analyzed. The ITS and four protein-coding genes (MCM7, RPB1, RPB2, and TSR1) were sequenced for 85 isolates. Based on an initial neighbor joining analysis of the concatenated genes, W. muriae remained monophyletic but four clades were found in W. sebi, which we designated as W. sebi clades 1, 2, 3, and 4. We hypothesized that these clades represent distinct phylogenetic species within the Wallemia sebi species complex (WSSC). We then conducted multiple phylogenetic analyses and demonstrated genealogical concordance, which supports the existence of four phylogenetic species within the WSSC. Geographically, W. muriae was only found in Europe, W. sebi clade 3 was only found in Canada, W. sebi clade 4 was found in subtropical regions, while W. sebi clade 1 and 2 were found worldwide. Haplotype analysis showed that W. sebi clades 1 and 2 had multiple haplotypes while W. sebi clades 3 and 4 had one haplotype and may have been under sampled. We describe W. sebi clades 2, 3, and 4 as new species in a companion study. PMID:25799362

  20. Lead abatement training for workers

    SciTech Connect

    Not Available

    1999-01-01

    This training program is designed to be a 16 hour training course. The course is designed to meet the requirements of 40 CFR Part 745 Lead. Requirements for Lead-Based Paint Activities in Target Housing and Child Occupied Facilities, a federal regulation under section 402 of the Toxic Substance Control Act (TSCA). Topics covered in the course include: where and what is lead; health effects; regulations and laws; identifying and evaluating hazards; controlling lead hazards; abatement methods; cleanup, disposal and clearance; and soil and exterior dust abatement.

  1. ETHAN'S HOUSE GETS HEALTHIER

    E-print Network

    and hasn't been tested, assume the building has lead paint. Tips to Prevent Exposure to Lead and Its for lead. Separate children from areas with lead dust and make sure your child cannot reach peeling paint chipping paint. Clean up loose paint chips with a wet mop. Do not dry sweep lead dust. Wet-mop floors

  2. Serum antibody to Sarcoptes scabiei and house dust mite prior to and during infestation with S. scabiei.

    PubMed

    Arlian, L G; Morgan, M S

    2000-07-01

    In this study, serum antibodies to Sarcoptes scabiei var. canis (SS), Dermatophagoides farinae (DF), and D. pteronyssinus (DP) were determined in 19 healthy, random-source dogs prior to infestation with scabies then again during a primary infestation, cure and challenge infestation with scabies. Prior to scabies infestation, serum of 11 dogs contained faintly detectable amounts of IgE and/or IgG to proteins in SS extract, probably resulting from sensitization to dust mites that share cross-reactive antigenic epitopes with SS. After becoming infested with scabies, the response to SS antigens became stronger with antibodies appearing to more antigens as the scabies infestation progressed. Three of the newly recognized proteins were 170, 155 and 142/133kD and could be used in a diagnostic test since antibodies to them appeared during the primary infestation. In addition, during the primary infestation, 14 of 15 dogs developed IgE to 1-11 new SS proteins in addition to an increase in IgE binding to those proteins recognized prior to infestation. Overall, the strongest antibody responses (IgE and IgG) were exhibited during cure of the first infestation, when dead mites were still present in the stratum corneum. As expected, the antibody response was strong and rapid during challenge when the infestation self-cured. The immunogenic SS proteins identified by serum antibody binding during challenge, when the hosts self-cured, are candidates for inclusion in a vaccine. These candidate proteins are 200, 185, 170, 155, 142/133, 112, 97, 74, 57, 45/42, 32 and 22kD. Some of the proteins in SS that exhibited new or increased antibody binding during the experiment also had IgE and IgG binding to proteins with similar molecular weights in DF and DP extracts. These results illustrate the difficulties involved in understanding and interpreting serum antibody for developing a serological test for the diagnosis of scabies, isolating relevant SS antigens that could be included in a vaccine for prevention of scabies, and for understanding the immune response mechanism to scabies. PMID:10856817

  3. Modelling and bioinformatics analysis of the dimeric structure of house dust mite allergens from families 5 and 21: Der f 5 could dimerize as Der p 5.

    PubMed

    Khemili, Souad; Kwasigroch, Jean Marc; Hamadouche, Tarik; Gilis, Dimitri

    2012-01-01

    Allergy represents an increasing thread to public health in both developed and emerging countries and the dust mites Dermatophagoides pteronyssinus (Der p), Blomia tropicalis (Blo t), Dermatophagoides farinae (Der f), Lepidoglyphus destructor (Lep d) and Suidasia medanensis (Sui m) strongly contribute to this problem. Their allergens are classified in several families among which families 5 and 21 which are the subject of this work. Indeed, their biological function as well as the mechanism or epitopes by which they are contributing to the allergic response remain unknown and their tridimensional structures have not been resolved experimentally except for Blo t 5 and Der p 5. Blo t 5 is a monomeric three helical bundle, whereas Der p 5 shows a three helical bundle with a kinked N-terminal helix that assembles in an entangled dimeric structure with a large hydrophobic cavity. This cavity could be involved in the binding of hydrophobic ligands, which in turn could be responsible for the shift of the immune response from tolerance to allergic inflammation. We used molecular modelling approaches to bring out if other house dust mite allergens of families 5 and 21 (Der f 5, Sui m 5, Lep d 5, Der p 21 and Der f 21) could dimerize and form a large cavity in the same way as Der p 5. Monomeric models were first performed with MODELLER using the experimental structures of Der p 5 and Blo t 5 as templates. The ClusPro server processed the selected monomers in order to assess their capacity to form dimeric structures with a positive result for Der p 5 and Der f 5 only. The other allergens (Blo t 5, Sui m 5, Lep d 5, Der p 21 and Der f 21) did not present such a propensity. Moreover, we identified mutations that should destabilize and/or prevent the formation of the Der p 5 dimeric structure. The production of these mutated proteins could help us to understand the role of the dimerization process in the allergic response induced by Der p 5, and if Der p 5 and Der f 5 behave similarly. PMID:22208271

  4. Rapid Lead Screening Test

    MedlinePLUS

    ... inhaling or ingesting dust from deteriorating lead-based paint. Symptoms of lead poisoning include headaches, stomach cramps, ... Control US Environmental Protection Agency (EPA): Lead in Paint, Dust, and Soil More in Products and Medical ...

  5. Establishing an allergic eczema model employing recombinant house dust mite allergens Der p 1 and Der p 2 in BALB/c mice

    PubMed Central

    Szalai, Krisztina; Kopp, Tamara; Lukschal, Anna; Stremnitzer, Caroline; Wallmann, Julia; Starkl, Philipp; Vander Elst, Luc; Saint-Remy, Jean-Marie; Pali-Schöll, Isabella; Jensen-Jarolim, Erika

    2012-01-01

    Abstract The major house dust mite allergens Der p 1 and Der p 2 are prevalent inducers of eczema. Der p 1 is a cysteine protease disrupting epithelial barriers, whereas Der p 2 functionally mimics the LPS-binding compound MD-2 within the TLR4 complex. In this work, we tested the percutaneous sensitizing capacity of recombinant (r) Der p 1 and Der p 2 in BALB/c mice. Mice were sensitized by percutaneous application of low (10 ?g/application) and high dose (100 ?g) rDer p 1 or rDer p 2, or with rDer p 1 followed by rDer p 2. Allergen-specific and total IgE antibodies were determined by ELISA. Eczema of BALB/c was classified by the itching score and corresponded to erosions. Infiltrating immune cells were identified by haematoxylin/eosin and Giemsa staining for eosinophils or mast cells, CD3 staining for T lymphocytes. Percutaneous treatments with rDer p 1, but not rDer p 2-induced specific IgG1. However, cotreatment with rDer p 1 led to increase in anti-Der p 2 IgG titres. Both allergens elicited skin erosions because of scratching, thickening of the epidermis, and eosinophil and T-cell infiltration. Our data indicate that recombinant mite allergens in the absence of adjuvant are sufficient for inducing eczema in BALB/c mice. As the enzymatic activity of an allergen might be an important cofactor for specific sensitization via the skin, Der p 1 may act as adjuvant for other allergens too. The presented mouse model is suitable for investigating the mechanisms of allergic eczema. PMID:23163649

  6. The effects of inhaled corticosteroids on intrinsic responsiveness and histology of airways from infant monkeys exposed to house dust mite allergen and ozone

    SciTech Connect

    Joad, Jesse P. [Department of Pediatrics, School of Medicine, University of California at Davis, Davis, CA 95616 (United States)], E-mail: jesse.joad@ucdmc.ucdavis.edu; Kott, Kayleen S.; Bric, John M. [Department of Pediatrics, School of Medicine, University of California at Davis, Davis, CA 95616 (United States); Schelegle, Edward S. [Department of Anatomy, Physiology, and Cell Biology, School of Veterinary Medicine, University of California at Davis, Davis, CA 95616 (United States); Gershwin, Laurel J. [Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California at Davis, Davis, CA 95616 (United States); Plopper, Charles G. [Department of Anatomy, Physiology, and Cell Biology, School of Veterinary Medicine, University of California at Davis, Davis, CA 95616 (United States); Peake, Janice L.; Pinkerton, Kent E. [Department of Pediatrics, School of Medicine, University of California at Davis, Davis, CA 95616 (United States)

    2008-01-15

    Inhaled corticosteroids (ICS) are recommended to treat infants with asthma, some with intermittent asthma. We previously showed that exposing infant monkeys to allergen/ozone resulted in asthma-like characteristics of their airways. We evaluated the effects of ICS on histology and intrinsic responsiveness of allergen/ozone-exposed and normal infant primate airways. Infant monkeys were exposed by inhalation to (1) filtered air and saline, (2) house dust mite allergen (HDMA) + ozone and saline, (3) filtered air and ICS (budesonide) or (4) HDMA + ozone and ICS. Allergen/ozone exposures started at 1 month and ICS at 3 months of age. At 6 months of age, methacholine-induced changes in luminal area of airways in proximal and distal lung slices were determined using videomicrometry, followed by histology of the same slices. Proximal airway responsiveness was increased by allergen/ozone and by ICS. Eosinophil profiles were increased by allergen/ozone in both proximal and distal airways, an effect that was decreased by ICS in distal airways. In both allergen/ozone- and air-exposed monkeys, ICS increased the number of alveolar attachments in distal airways, decreased mucin in proximal airways and decreased epithelial volume in both airways. ICS increased smooth muscle in air-exposed animals while decreasing it in allergen/ozone-exposed animals in both airways. In proximal airways, there was a small but significant positive correlation between smooth muscle and airway responsiveness, as well as between alveolar attachments and responsiveness. ICS change morphology and function in normal airways as well as allergen/ozone-exposed airways, suggesting that they should be reserved for infants with active symptoms.

  7. Dust to Dust

    NSDL National Science Digital Library

    The dust around us is composed of bits of detritus of all manner of things, but it is mostly bits of human skin. This radio broadcast explores the universe through tiny dust particles and discovers what it can tell us about our past as well as our future. The broadcast discusses dust from ice cores that reveal the climate record and the cosmic dust that Earth is gathering every day. There is also explanation of the microscopic composition of the dust around us and the damage dust can do to museum exhibits, especially when the dust interacts with the moisture in the atmosphere. The broadcast is 28 minutes in length.

  8. Chemical concentrations of pollutant lead aerosols, terrestrial dusts and sea salts in Greenland and Antarctic snow strata

    Microsoft Academic Search

    M. Murozumi; Tsaihwa J. Chow; C. Patterson

    1969-01-01

    In this study we report analyses of lead in annual ice layers from the interior of northern Greenland and in annual layers of ice from the interior of the Antarctic continent. We show that lead concentrations increase from 0.200 Pb\\/kg ice today in north pole ice sheets, the sharpest rise occurring after 1940, and that the levels of lead in

  9. 77 FR 70179 - Requirements for Lead-Based Paint Hazards in Federally Owned Residential Properties and Housing...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-23

    ...FR-5603-N-87] Requirements for Lead-Based Paint Hazards in Federally Owned Residential...Requirements for notification of leadbased paint hazard in federally-owned residential...Proposed: Requirements for Lead-Based Paint Hazards in Federally Owned...

  10. Group 1 Allergen Genes in Two Species of House Dust Mites, Dermatophagoides farinae and D. pteronyssinus (Acari: Pyroglyphidae): Direct Sequencing, Characterization and Polymorphism

    PubMed Central

    Shafique, Rubaba Hamid; Klimov, Pavel B.; Inam, Muhammad; Chaudhary, Farhana Riaz; OConnor, Barry M.

    2014-01-01

    Group 1 allergens of Dermatophagoides farinae (Der f 1) and D. pteronyssinus (Der p 1) dominate overall allergic responses in house dust mite allergy patients. The need for accurate identification and characterization of representative variants of group 1 allergens in any given geographic locality has been emphasized for development of appropriate allergen extracts. Regional amino acid sequence polymorphism has been described but the extent of this polymorphism is not well understood. Such data are completely absent for the USA and many other countries. Most previous studies used cDNA libraries generated by reverse transcriptase (RT-PCR) and/or primers amplifying shorter fragments of this gene. Using novel species-specific primers and direct PCR, we document group 1 allergen gene sequence polymorphism in populations of D. farinae and D. pteronyssinus from the USA and Pakistan. We report two novel introns (nt pos 87 and 291) in both species, and the absence of intron 3 in Der p 1. Thirteen silent and one novel non-synonymous mutation (Tryptophan W197 to Arginine R197) were detected in D. farinae. The potential medical significance of the latter mutation is discussed. Two haplotypes of the Der f 1 gene were identified, haplotype 1 (63%) was more frequent than haplotype 2 (18%). Polymorphism in Der f 1 displayed geographical localization, since both haplotypes were present in mite populations from Pakistan whereas haplotype 1 was observed only in the USA. In Der p 1, a silent mutation at nt (aa) position 1011(149) and four non-synonymous mutations at positions 589(50), 935(124), 971(136), 1268(215) were observed. These mutations were reported from many other geographic regions, suggesting that polymorphism in the Der p 1 gene is panmictic. The extent of polymorphism in both genes is substantially lower than that reported previously (0.10–0.16% vs 0.31–0.49%), indicating the need for careful evaluation of potential polymerase errors in studies utilizing RT-PCR. PMID:25494056

  11. Block Copolymer/DNA Vaccination Induces a Strong Allergen-Specific Local Response in a Mouse Model of House Dust Mite Asthma

    PubMed Central

    Roussey-Bihouée, Tiphaine; Hassoun, Dorian; Evrard, Justine; Cheminant, Marie-Aude; Chesné, Julie; Braza, Faouzi; Mahay, Guillaume; Portero, Vincent; Sagan, Christine; Pitard, Bruno; Magnan, Antoine

    2014-01-01

    Background Allergic asthma is caused by abnormal immunoreactivity against allergens such as house dust mites among which Dermatophagoides farinae (Der f) is a common species. Currently, immunotherapy is based on allergen administration, which has variable effect from patient to patient and may cause serious side effects, principally the sustained risk of anaphylaxis. DNA vaccination is a promising approach by triggering a specific immune response with reduced allergenicity. Objective The aim of the study is to evaluate the effects of DNA immunization with Der f1 allergen specific DNA on allergic sensitization, inflammation and respiratory function in mice. Methods Mice were vaccinated 28 and 7 days before allergen exposure with a Der f1-encoding plasmid formulated with a block copolymer. Asthma was induced by skin sensitization followed by intra-nasal challenges with Der f extract. Total lung, broncho-alveolar lavage (BAL) and spleen cells were analyzed by flow cytometry for their surface antigen and cytokine expression. Splenocytes and lung cell IFN-? production by CD8+ cells in response to Der f CMH1-restricted peptides was assessed by ELISPOT. IgE, IgG1 and IgG2a were measured in serum by ELISA. Specific bronchial hyperresponsiveness was assessed by direct resistance measurements. Results Compared to animals vaccinated with an irrelevant plasmid, pVAX-Der f1 vaccination induced an increase of B cells in BAL, and an elevation of IL-10 and IFN-? but also of IL-4, IL-13 and IL-17 producing CD4+ lymphocytes in lungs and of IL-4 and IL-5 in spleen. In response to CD8-restricted peptides an increase of IFN-? was observed among lung cells. IgG2a levels non-specifically increased following block copolymer/DNA vaccination although IgE, IgG1 levels and airways resistances were not impacted. Conclusions & Clinical Relevance DNA vaccination using a plasmid coding for Der f1 formulated with the block copolymer 704 induces a specific immune response in the model of asthma used herein. PMID:24497934

  12. House dust allergy and immunotherapy

    PubMed Central

    Thomas, Wayne R.

    2012-01-01

    HDM allergy is associated with asthma, allergic rhinitis and atopic dermatitis. In many countries childhood asthma is predominantly found in HDM-allergic children with their probability of developing disease being proportional to their IgE antibody titers and the early development of Th2 responses. While the pathogenesis is complex and increasingly linked to infection the immunologically-based allergen immunotherapy and anti-IgE antibody therapy are highly beneficial. Immunotherapy could be a short-term treatment providing lifelong relief but the current regimens depend on repeated administration of allergen over years. Immunological investigations point to a contribution of responses outside the Th2 pathway and multiple potential but unproven control mechanisms. Over half of the IgE antibodies are directed to the group 1 and 2 allergens with most of remainder to the group 4, 5, 7 and 21 allergens. This hierarchy found in high and low responders provides a platform for introducing defined allergens into immunotherapy and defined reagents for investigation. PMID:22894952

  13. 40 CFR 745.226 - Certification of individuals and firms engaged in lead-based paint activities: target housing and...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...appropriate work practice standards for lead-based paint activities...constitutes evidence of a failure...engaged in lead-based paint activities...with the work practice standards established...local lead-based paint statutes...constitutes evidence of a...

  14. 40 CFR 745.227 - Work practice standards for conducting lead-based paint activities: target housing and child...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... false Work practice standards for conducting lead-based paint activities...227 Work practice standards for conducting lead-based paint activities...pursuant to the work practice standards contained... (1) Lead-based paint is present...which there is evidence of teeth...

  15. 40 CFR 745.227 - Work practice standards for conducting lead-based paint activities: target housing and child...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... false Work practice standards for conducting lead-based paint activities...227 Work practice standards for conducting lead-based paint activities...pursuant to the work practice standards contained... (1) Lead-based paint is present...which there is evidence of teeth...

  16. 40 CFR 745.226 - Certification of individuals and firms engaged in lead-based paint activities: target housing and...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...appropriate work practice standards for lead-based paint activities...constitutes evidence of a failure...engaged in lead-based paint activities...with the work practice standards established...local lead-based paint statutes...constitutes evidence of a...

  17. 75 FR 13127 - Lead-Based Paint Renovation, Repair and Painting Activities in Target Housing and Child Occupied...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-18

    ...EPA-R07-OPPT-2010-0155; FRL-9128-4] Lead-Based Paint Renovation, Repair and Painting Activities...statute was the Residential Lead-Based Paint Hazard Reduction Act of 1992. That Act...EPA-authorized programs for lead-based paint activities training and certification...

  18. Effect of inhaled dust mite allergen on regional particle deposition and mucociliary clearance in allergic asthmatics**

    EPA Science Inventory

    Background Acute exacerbations in allergic asthmatics may lead to impaired ability to clear mucus from the airways, a key factor in asthma morbidity. Objective The purpose of this study was to determine the effect of inhaled house dust mite challenge on the regional deposition of...

  19. Occurrence and levels of polybrominated diphenyl ethers (PBDEs) in house dust and hair samples from Northern Poland; an assessment of human exposure.

    PubMed

    Król, Sylwia; Namie?nik, Jacek; Zabiega?a, Bo?ena

    2014-09-01

    Polybrominated diphenyl ethers (PBDEs) are among most ubiquitous compounds to be found in indoor environment and ingestion of household dust is considered an important route of exposure to PBDEs, especially in toddlers and young children. The present work reported concentration levels of PBDE congeners (PBDE-28, -47, -99, -100, -153, -154, -183 and -209) in hair and dust samples from selected households from Northern Poland. The concentrations of PBDEs in dust ranged from dust. The estimated exposure to ?PBDEs via ingestion of household dust varied from 21 to 92ngd(-1) in toddlers and from 3.7 to 20ngd(-1) in adults. By comparison of correlation between the concentrations of PBDEs in paired hair and dust samples the present work also investigated the possibility of use of hair for reflecting the actual exposure to PBDEs in humans. Finally the possible uncertainties associated with exposure assessment were investigated in the present study. PMID:24630866

  20. Comprehensive and workable plan for the abatement of lead-based paint in privately owned housing. Report to the Congress

    SciTech Connect

    Weitz, S.; Clickner, R.P.; Blackburn, A.; Buches, D.

    1991-01-01

    The report proposes a balanced and comprehensive plan designed to overcome the barriers that have inhibited efforts to address the hazards of lead-based paint in the past, and to support State and local governments and the private sector in the difficult but necessary task of reducing these hazards in American homes. The report focuses on lead paint abatement, as mandated by the Congress.

  1. EVALUATION OF PORTABLE X-RAY FLUORESCENCE SPECTROMETER FOR MEASUREMENT OF LEAD IN PAINT, SOIL AND DUST

    EPA Science Inventory

    Three widely used commercially available portable X-ray fluorescence spectrometers were evaluated for precision and accuracy of measurement of lead in paint. ncluded were two direct reading instruments and one spectrum analyzer. est materials were prepared by spiking oil-based an...

  2. Lead Toxicity

    MedlinePLUS

    ... are exposed through lead-contaminated household dust or soil that gets into their mouths. • Homes that were ... out of areas in the yard with bare soil. o Wash children’s hands and toys with soap ...

  3. Experimentally increased in ovo testosterone leads to increased plasma bactericidal activity and decreased cutaneous immune response in nestling house wrens.

    PubMed

    Clairardin, Sandrine G; Barnett, Craig A; Sakaluk, Scott K; Thompson, Charles F

    2011-08-15

    Maternally derived testosterone in the eggs of birds may benefit nestlings by increasing various aspects of their growth, condition and behavioral development, but these benefits may come at a cost, including suppression of immune responsiveness. Experiments on a variety of species in which in ovo levels of testosterone have been experimentally increased have produced mixed results; some have found increased growth and suppressed immune function of nestlings whereas others have found the opposite. In an attempt to clarify the relationship between in ovo testosterone and nestling size, mass, health state and immune responsiveness, we experimentally increased levels of testosterone in the eggs of house wrens (Troglodytes aedon). We simultaneously determined the size, mass, hematocrit (a measure of health state), cutaneous immune response to phytohaemagglutinin and plasma bactericidal activity of nestlings near the time of fledging. We predicted that nestlings hatching from testosterone-injected eggs would exhibit lower immune responsiveness, but achieve greater mass, size and condition, than nestlings hatching from vehicle-injected control eggs. Instead, we found that nestlings hatching from testosterone-injected eggs had a weaker cutaneous immune response but greater bactericidal activity than those hatching from control eggs. They did not, however, differ significantly in mass, size or hematocrit from controls. These results suggest that experimentally increased in ovo testosterone induced a trade-off between bactericidal activity and the cutaneous immune response. The opposite responses by two different measures of immune function to experimentally increased in ovo testosterone underscore the importance of including multiple immune assays when investigating the potential for trade-offs with the immune system and other physiological functions. PMID:21795576

  4. Family Housing Wysocki House

    E-print Network

    Massachusetts at Amherst, University of

    Family Housing Wysocki House 911 North Pleasant Street University of Massachusetts Amherst, MA):________________________________________ STUDENT ENROLLMENT: Undergrad Graduate Are you a current Family Housing Tenant?_________ UMASS STAFF WOULD LIKE US TO KNOW? LIST REMARKS BELOW: SEE REVERSE SIDE FOR APARTMENT PREFERENCE SELECTION FAMILY

  5. Modelling and Bioinformatics Analysis of the Dimeric Structure of House Dust Mite Allergens from Families 5 and 21: Der f 5 Could Dimerize as Der p 5

    Microsoft Academic Search

    Souad Khemili; Jean Marc Kwasigroch; Tarik Hamadouche; Dimitri Gilis

    2012-01-01

    Allergy represents an increasing thread to public health in both developed and emerging countries and the dust mites Dermatophagoides pteronyssinus (Der p), Blomia tropicalis (Blo t), Dermatophagoides farinae (Der f), Lepidoglyphus destructor (Lep d) and Suidasia medanensis (Sui m) strongly contribute to this problem. Their allergens are classified in several families among which families 5 and 21 which are the

  6. House dust mite and cockroach exposure are strong risk factors for positive allergy skin test responses in the Childhood Asthma Management Program

    Microsoft Academic Search

    Karen Huss; N. Franklin Adkinson; Peyton A. Eggleston; Christopher Dawson; Mark L. Van Natta; Robert G. Hamilton

    2001-01-01

    Background: Children with asthma have a high prevalence of environmental allergies, especially to indoor allergens. The relationships of exposure to indoor allergens (dust mites, cat, dog, cockroach, and molds) and other host factors to allergy sensitization have not been evaluated simultaneously in a large cohort. Objectives: We studied 1041 children aged 5 to 12 years with mild-to-moderate asthma to determine

  7. Measurement of nicotine in household dust

    SciTech Connect

    Kim, Sungroul [Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Institute for Global Tobacco Control, 627 N. Washington Street, 2nd Floor Baltimore, MD 21205 (United States); Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205 (United States)], E-mail: srkim@jhsph.edu; Aung, Ther; Berkeley, Emily [Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205 (United States); Diette, Gregory B. [Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205 (United States); Department of Medicine, Johns Hopkins University School of Medicine (United States); Breysse, Patrick N. [Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205 (United States)

    2008-11-15

    An analytical method of measuring nicotine in house dust was optimized and associations among three secondhand smoking exposure markers were evaluated, i.e., nicotine concentrations of both house dust and indoor air, and the self-reported number of cigarettes smoked daily in a household. We obtained seven house dust samples from self-reported nonsmoking homes and 30 samples from smoking homes along with the information on indoor air nicotine concentrations and the number of cigarettes smoked daily from an asthma cohort study conducted by the Johns Hopkins Center for Childhood Asthma in the Urban Environment. House dust nicotine was analyzed by isotope dilution gas chromatography-mass spectrometry (GC/MS). Using our optimized method, the median concentration of nicotine in the dust of self-reported nonsmoking homes was 11.7 ng/mg while that of smoking homes was 43.4 ng/mg. We found a substantially positive association (r=0.67, P<0.0001) between house dust nicotine concentrations and the numbers of cigarettes smoked daily. Optimized analytical methods showed a feasibility to detect nicotine in house dust. Our results indicated that the measurement of nicotine in house dust can be used potentially as a marker of longer term SHS exposure.

  8. Multiple metal contamination from house paints: consequences of power sanding and paint scraping in New Orleans.

    PubMed Central

    Mielke, H W; Powell, E T; Shah, A; Gonzales, C R; Mielke, P W

    2001-01-01

    Power sanding exterior paint is a common practice during repainting of old houses in New Orleans, Louisiana, that triggers lead poisoning and releases more than Pb. In this study we quantified the Pb, zinc, cadmium, manganese, nickel, copper, cobalt, chromium, and vanadium in exterior paint samples collected from New Orleans homes (n = 31). We used interior dust wipes to compare two exterior house-painting projects. House 1 was measured in response to the plight of a family after a paint contractor power sanded all exterior paint from the weatherboards. The Pb content (approximately 130,000 microg Pb/g) was first realized when the family pet died; the children were hospitalized, the family was displaced, and cleanup costs were high. To determine the quantity of dust generated by power sanding and the benefits of reducing Pb-contaminated dust, we tested a case study house (house 2) for Pb (approximately 90,000 microg/g) before the project was started; the house was then dry scraped and the paint chips were collected. Although the hazards of Pb-based paints are well known, there are other problems as well, because other toxic metals exist in old paints. If house 2 had been power sanded to bare wood like house 1, the repainting project would have released as dust about 7.4 kg Pb, 3.5 kg Zn, 9.7 g Cd, 14.8 g Cu, 8.8 g Mn, 1.5 g Ni, 5.4 g Co, 2.4 g Cr, and 0.3 g V. The total tolerable daily intake (TTDI) for a child under 6 years of age is 6 microg Pb from all sources. Converting 7.4 kg Pb to this scale is vexing--more than 1 billion (10(9)) times the TTDI. Also for perspective, the one-time release of 7.4 x 10(9) microg of Pb dust from sanding compares to 50 x 10(9) microg of Pb dust emitted annually per 0.1 mile (0.16 km) from street traffic during the peak use of leaded gasoline. In this paper, we broaden the discussion to include an array of metals in paint and underscore the need and possibilities for curtailing the release of metal dust. PMID:11673129

  9. Vacuum Head Removes Sanding Dust

    NASA Technical Reports Server (NTRS)

    Bengle, C. G.; Holt, J. W.

    1982-01-01

    Vacuum sander prevents sanding dust from entering a work area, since dust particles are drawn off as quickly as they are produced. Tool is useful where dust presents health hazards, interferes with such processes as semiconductor manufacture, or could destroy wet paint or varnish finishes. Could be used to sand such materials as lead paint.

  10. Environmental Lead after Hurricane Katrina: Implications for Future Populations

    PubMed Central

    Iqbal, Shahed; Perry, Sara; Arroyave, Whitney; Rice, Janet C.

    2011-01-01

    Background: As a result of Hurricane Katrina, > 100,000 homes were destroyed or damaged and a significant amount of sediment was deposited throughout the city of New Orleans, Louisiana. Researchers have identified the potential for increased lead hazards from environmental lead contamination of soils. Objectives: We assessed the distribution of residential soil and dust lead 2 years poststorm and compared soil lead before and after the storm. Methods: We conducted a cross-sectional study in New Orleans in which households were selected by stratified random sampling. A standard residential questionnaire was administered, and lead testing was performed for both the interior and exterior of homes. Logistic regression was used to identify significant predictors of interior and exterior lead levels in excess of allowable levels. Results: One hundred nine households were enrolled; 61% had at least one lead measurement above federal standards. Of homes with bare soil, 47% had elevated lead and 27% had levels exceeding 1,200 ppm. Housing age was associated with soil lead, and housing age and soil lead were associated with interior lead. Race, income, and ownership status were not significantly associated with either interior or exterior lead levels. The median soil lead level of 560 ppm was significantly higher than the median level of samples collected before Hurricane Katrina. Conclusions: The high prevalence (61%) of lead above recommended levels in soil and dust samples in and around residences raises concern about potential health risks to the New Orleans population, most notably children. Steps should be taken to mitigate the risk of exposure to lead-contaminated soil and dust. Further research is needed to quantify the possible contribution of reconstruction activities to environmental lead levels. PMID:22052045

  11. Biology, ecology, and prevalence of dust mites.

    PubMed

    Arlian, Larry G; Morgan, Marjorie S

    2003-08-01

    The house dust mites D. farinae, D. pteronyssinus, and E. maynei are sources of multiple potent allergens in the indoor environment. They are common inhabitants in homes worldwide. Many biologically significant studies have revealed how well adapted these mites are to the microhabitats in homes. Ambient RH is a key factor in determining where these mites are found. Many aspects of the biology of house dust mites are not understood. A greater understanding of the biology of dust mites may reveal new strategies for controlling dust mites and their allergens in homes. PMID:14524385

  12. Lead and Your Health

    MedlinePLUS

    ... of products found in and around homes, including paint and gasoline. Where is lead found now? Lead can still be found in lead-based paint used in older homes, contaminated soil, household dust, ...

  13. The effect of house dust mite sensitization on lung size and airway caliber in symptomatic and nonsymptomatic preadolescent children: a community-based study in Poland.

    PubMed Central

    Jedrychowski, Wieslaw; Maugeri, Umberto; Jedrychowska-Bianchi, Iwona; Mróz, Elzbieta

    2002-01-01

    There are conflicting reports on the effects of atopy on lung function. The purpose of this study was to compare the effects of house mite (HM) atopy on lung function in subsamples of 12-year-old symptomatic and nonsymptomatic preadolescent children taken from the community sample. An additional objective of this study was to identify possible environmental determinants of HM skin reaction. We obtained questionnaire data on respiratory symptoms and skin-prick tests and performed spirometry on a subsample of 311 children of a birth cohort of children who have been followed over 3 years. Multivariate regression analysis showed progressive decrement of lung function indices (forced vital capacity, forced expiratory volume in 1 sec, and forced expiratory flow, midexpiratory phase) with increasing degree of HM atopy reflected by the skin reaction to HM allergens. The apparent association between the level of HM atopy and the lung function indices was highly significant in symptomatic individuals but insignificant in nonsymptomatic subjects. HM sensitization was significantly associated with mother's atopy. It occurred predominantly in boys and was related to the use of coal or gas for house heating. The effect of allergen sensitization on lung size and airway caliber confined to symptomatic subjects may reflect the inflammatory status of bronchial airways in the symptomatic subjects. PMID:12055047

  14. Standard operating procedure for the laboratory analysis of lead in paint, bulk dust, and soil by ultrasonic, acid digestion and inductively coupled plasma emission spectrometric measurement

    SciTech Connect

    Grohse, P.M.; Gutknecht, W.F.; Luk, K.K.; Wilson, B.M.; Van Hise, C.C.

    1997-09-01

    The details and performance of a simplified extraction procedure and analysis for three media are provided. Paint, bulk dust, and soil are collected using standard or referenced methods. Up to 0.25 g of paint, bulk dust, or soil weighted out and placed in a 50-mL centrifuge tube. Five mL of 25% (v/v) nitric acid is added and the sample is ultrasonicated for 30 minutes.

  15. Health and environmental outcomes of traditional and modified practices for abatement of residential lead-based paint

    Microsoft Academic Search

    M. R. Farfel; J. J. Jr. Chisolm

    1990-01-01

    We evaluated traditional and modified practices for abating lead-based paint in homes of children with blood-lead concentrations (PbB) greater than 1.4 mumol\\/L (greater than 29 micrograms\\/dl). Traditional abatement resulted in acute increases in: (1) lead contaminated house dust (generally 3 to 6-fold over pre-abatement levels, but at abated sites typically 10 to 100-fold); and (2) the PbBs of nearly half

  16. Atmospheric Dust

    NSDL National Science Digital Library

    2014-09-14

    Atmospheric dust storms are common in many of the world's semi-arid and arid regions and can impact local, regional, and even global weather, agriculture, public health, transportation, industry, and ocean health. This module takes a multifaceted approach to studying atmospheric dust storms. The first chapter examines the impacts of dust storms, the physical processes involved in their life cycle, their source regions, and their climatology. The second chapter explores satellite products (notably dust RGBs) and dust models used for dust detection and monitoring, and presents a process for forecasting dust storms. The third and final chapter of the module examines the major types of dust storms: those that are synoptically forced, such as pre- and post-frontal dust storms and those induced by large-scale trade winds; and those caused by mesoscale systems such as downslope winds, gap flow, convection, and inversion downburst storms.

  17. Aaron House From: Aaron House

    E-print Network

    He, Chuan

    1 Aaron House From: Aaron House Sent: Tuesday, January 28, 2014 3:27 PM To://finserv.uchicago.edu/award/benefits.shtml If you have questions, email finservhelp@lists.uchicago.edu Aaron House Training Manager

  18. An evaluation of the effectiveness of lead paint hazard reduction when conducted by homeowners and landlords

    SciTech Connect

    Etre, L.A.; Reynolds, S.J.; Burmeister, L.F.; Whitten, P.S.; Gergely, R.

    1999-08-01

    This research project was conducted in collaboration with the Iowa Department of Public Health to evaluate whether property owners who follow recommended procedures for lead-based paint removal/repair can do the work safely and effectively. This study included 29 homes where a lead-based paint hazard had been identified and lead-based paint was removed or repaired (hazard reduction). Exposure evaluation included pre-project surface dust wipe sampling, air monitoring during lead-based paint removal, post-project surface dust wipe sampling, and pre- and post-project blood samples from adult study participants. The comparison of surface dust wipe samples taken before and after lead paint hazard reduction was used to evaluate the effectiveness of lead paint hazard reduction. The lead loadings on window sill surfaces in the work area were significantly lower after completion of the project, and the lead-based paint removal did not contaminate the adjoining living area. The proportion of homes with surface dust lead loading exceeding Department of Housing and Urban Development (HUD) clearance standard was 73% pre-project and 38% post-project. Personal airborne exposures during lead removal activities reinforce the need to respiratory protection and good hygiene. There was no difference in adult pre-/post-blood levels, indicating that participants die remove lead in a safe manner with respect to their own exposures. The results indicate that hazard reduction can be done effectively when recommended procedures for the removal of lead-based paint are followed.

  19. Implications of different residential lead standards on children's blood lead levels in France: predictions based on a national cross-sectional survey.

    PubMed

    Oulhote, Youssef; LeTertre, Alain; Etchevers, Anne; Le Bot, Barbara; Lucas, Jean-Paul; Mandin, Corinne; Le Strat, Yann; Lanphear, Bruce; Glorennec, Philippe

    2013-11-01

    Despite the dramatic reductions in children's blood lead levels (BLLs), there is considerable evidence that low-level lead exposure is associated with intellectual deficits and behavioral problems, without apparent threshold. There are limited data, however, about the contribution of residential sources of lead to contemporary children's blood lead levels. The aim of this study is to calculate the contributions of residential sources of lead to assess the potential impact of setting new standards for lead levels in residential dust, soil and water. We enrolled 484 French children aged from 6 months to 6 years, and collected data on social, housing and individual characteristics. Lead concentrations in blood and environmental samples (water, soils, and dusts) were measured using inductively coupled plasma mass spectrometry. Data were analyzed using a multivariate generalized additive model accounting for the sampling design and the sampling weights. We found that exceedingly low concentrations of lead in dust, soil and water were significant predictors of children's BLLs, after adjustment for potential confounding variables. Lead-contaminated floor dust was the main source of lead in blood. BLLs (GM: 14?g/L) increased by 65%, 13%, 25%, and 5% when lead content in floor dust, loose soil, hard soil and water increased from their 25th percentile to their 95th percentile, respectively. We also observed that the steepest increase in BLLs occurred at the lowest levels of lead-contaminated floor dust, which indicates that lead contamination should be kept as low as possible. Impact of different possible standards on children's BLLs was also tabulated and indicated that unless standards are set low, they will only benefit a small proportion of children who have the highest exposures. PMID:23528234

  20. The Lead-Safe Certified Guide to Renovate Right

    MedlinePLUS

    ... get lead in their bodies from lead in soil or paint chips. Lead dust is often invisible. • ... from deteriorating lead-based paint and lead-contaminated soil that gets tracked into your home. This dust ...

  1. Dust Storm

    Atmospheric Science Data Center

    2013-04-16

    article title:  Massive Dust Storm over Australia     View Larger Image ... and dry conditions caused a massive blanket of dust from Australia's Outback to spread eastward across Queensland and New South Wales. ...

  2. Dust Storm

    Atmospheric Science Data Center

    2013-04-16

    article title:  Elevated Dust over the Middle East     View ... on April 11, 2004 (top panels) contrast strongly with the dust storm that swept across Iraq and Saudi Arabia on May 13, 2004 (bottom ... (MISR) depict both the abundance of airborne dust, and its height above the surface. The natural-color views at left ...

  3. Aaron House From: Aaron House

    E-print Network

    He, Chuan

    1 Aaron House From: Aaron House Sent: Thursday, February 27, 2014 9:50 AM To the webinar. Aaron House Training Manager University Research Administration The University of Chicago House [mailto:ahouse@uchicago.edu] Sent: Friday, February 21, 2014 1:19 PM To: Grantsadmin

  4. Poets House

    NSDL National Science Digital Library

    Poets House is an organization that focuses on modern poetry and is a "national poetry library and literary center that invites poets and the public to step into the living tradition of poetry." The website of this New York-based treasure is now in Battery Park City, and houses a 50,000 volume poetry collection of varied media, including journals, audio, video, and digital media. The "News" tab offers a slideshow of "Poetry Hard-Hat Tours" that has almost two dozen photos of the progress of the building of the new Battery Park City location. The "Programs" tab on the left hand menu leads the visitors to a "Calendar of Events", as well as descriptions of the events on the calendar, such as "Seminars and Workshops", "Showcase Events" and "Conversations on Poetics". The "Directory" tab on the left hand menu offers a free 20,000 title online database of poetry titles published between 1990 and 2008, and is searchable by numerous criteria, as well as sortable by author, title, or publisher.

  5. House Dust Mite Allergen Der f 2-induced Phospholipase D1 Activation Is Critical for the Production of Interleukin-13 through Activating Transcription Factor-2 Activation in Human Bronchial Epithelial Cells*

    PubMed Central

    Park, Shin-Young; Cho, Ju Hwan; Oh, Doo-Yi; Park, Jung-Won; Ahn, Myung-Ju; Han, Joong-Soo; Oh, Jae-Won

    2009-01-01

    The purpose of this study was to identify the role of phospholipase D1 (PLD1) in Der f 2-induced interleukin (IL)-13 production. The major house dust mite allergen, Der f 2, increased PLD activity in human bronchial epithelial cells (BEAS-2B), and dominant negative PLD1 or PLD1 siRNA decreased Der f 2-induced IL-13 expression and production. Treatment of Der f 2 activated the phospholipase C? (PLC?)/protein kinase C? (PKC?)/p38 MAPK pathway. Der f 2-induced PLD activation was attenuated by PLC? inhibitors (U73122 and PAO), PKC? inhibitors (RO320432 and GO6976), and p38 MAPK inhibitors (SB203580 and SB202190). These results indicate that PLC?, PKC?, and p38 MAPK act as upstream activators of PLD in Der f 2-treated BEAS-2B cells. Furthermore, expression and production of IL-13 increased by Der f 2 were also blocked by inhibition of PLC?, PKC?, or p38 MAPK, indicating that IL-13 expression and production are related to a PLC?/PKC?/p38 MAPK pathway. We found that activating transcription factor-2 (ATF-2) was activated by Der f 2 in BEAS-2B cells and activation of ATF-2 was controlled by PLD1. When ATF-2 activity was blocked with ATF-2 siRNA, Der f 2-induced IL-13 expression and production were decreased. Thus, ATF-2 might be one of the transcriptional factors for the expression of IL-13 in Der f 2-treated BEAS-2B cells. Taken together, PLD1 acts as an important regulator in Der f 2-induced expression and production of IL-13 through activation of ATF-2 in BEAS-2B cells. PMID:19487697

  6. Lunar Dust Mitigation Screens

    NASA Astrophysics Data System (ADS)

    Knutson, Shawn; Holloway, Nancy

    With plans for the United States to return to the moon, and establish a sustainable human presence on the lunar surface many issues must be successfully overcome. Lunar dust is one of a number of issues with the potential to create a myriad of problems if not adequately addressed. Samples of dust brought back from Apollo missions show it to be soft, yet sharp and abrasive. The dust consists of a variety of morphologies including spherical, angular blocks, shards, and a number of irregular shapes. One of the main issues with lunar dust is its attraction to stick to anything it comes in contact with (i.e. astronauts, equipment, habitats, etc.). Ionized radiation from the sun strikes the moon's surface and creates an electrostatic charge on the dust. Further, the dust harbors van der Waals forces making it especially difficult to separate once it sticks to a surface. During the Apollo missions, it was discovered that trying to brush the lunar dust from spacesuits was not effective, and rubbing it caused degradation of the suit material. Further, when entering the lunar module after moonwalks, the astronauts noted that the dust was so prolific inside the cabin that they inhaled and ingested it, causing at least one of them, Harrison "Jack" Schmidt, to report irritation of the throat and lungs. It is speculated that the dust could also harm an astronaut's nervous and cardiovascular systems, especially during an extended stay. In addition to health issues, the dust can also cause problems by scouring reflective coatings off of thermal blankets, and roughening surfaces of windows and optics. Further, panels on solar cells and photovoltaics can also be compromised due to dust sticking on the surfaces. Lunar dust has the capacity to penetrate seals, interfere with connectors, as well as mechanisms on digging machines, all of which can lead to problems and failure. To address lunar dust issues, development of electrostatic screens to mitigate dust on sur-faces is currently being developed in a collaborative effort between Langley Research Center and Kennedy Space Center. The screens typically consist of spiral shaped conductive traces patterned on high dielectric substrates (i.e. glass, quartz, polyimide film, etc.). Two broad categories of substrate materials are being investigated for the screens. One category consists of transparent substrates (i.e. glass, quartz, sapphire, etc.), and the other non-transparent sub-strates (Kapton, polyimide films, metals, etc.). The transparent screens utilize patterns made from indium tin oxide (ITO), a transparent conductive material, on clear substrates while the non-transparent screens use copper patterns on a transluscent or opaque substrates. Further, the screen is coated with a high dielectric polyimide cover layer to protect the screen pattern. One promising cover layer material that is currently being investigated is Langley Research Center-Soluble Imide (LaRC-SI), a NASA LaRC developed polyimide. Lastly, a top-coat of hard, inorganic material is evaporated onto the cover layer for protection from scratches due to abrasive nature of the dust. Of note, several top-coat materials are under investigation and include: aluminum oxide, silicon dioxide, titanium oxide, yttrium oxide, zirconium oxide, and zinc sulfide. The electrostatic dust mitigation screens function when a high voltage (700V or greater) is applied to the screen electrodes, thus creating an electromagnetic wave across the surface of the screen that repels the dust. Lunar dust typically contains a high positive charge; therefore, the screens are charged with a higher positive charge that effectively repels dust from the surface (i.e. like charges repel, unlike charges attract). It is anticipated that full development and maturation of this technology will enable humans to sustain a long term presence on the moon, and other planets where dust may have negative implications.

  7. Protoplanetary Dust

    NASA Astrophysics Data System (ADS)

    Apai, Dániel; Lauretta, Dante S.

    2010-01-01

    Preface; 1. Planet formation and protoplanetary dust Daniel Apai and Dante Lauretta; 2. The origins of protoplanetary dust and the formation of accretion disks Hans-Peter Gail and Peter Hope; 3. Evolution of protoplanetary disk structures Fred Ciesla and Cornelius P. Dullemond; 4. Chemical and isotopic evolution of the solar nebula and protoplanetary disks Dmitry Semenov, Subrata Chakraborty and Mark Thiemens; 5. Laboratory studies of simple dust analogs in astrophysical environments John R. Brucato and Joseph A. Nuth III; 6. Dust composition in protoplanetaty dust Michiel Min and George Flynn; 7. Dust particle size evolution Klaus M. Pontoppidan and Adrian J. Brearly; 8. Thermal processing in protoplanetary nebulae Daniel Apai, Harold C. Connolly Jr. and Dante S. Lauretta; 9. The clearing of protoplanetary disks and of the protosolar nebula Ilaira Pascucci and Shogo Tachibana; 10. Accretion of planetesimals and the formation of rocky planets John E. Chambers, David O'Brien and Andrew M. Davis; Appendixes; Glossary; Index.

  8. Protoplanetary Dust

    NASA Astrophysics Data System (ADS)

    Apai, D.´niel; Lauretta, Dante S.

    2014-02-01

    Preface; 1. Planet formation and protoplanetary dust Daniel Apai and Dante Lauretta; 2. The origins of protoplanetary dust and the formation of accretion disks Hans-Peter Gail and Peter Hope; 3. Evolution of protoplanetary disk structures Fred Ciesla and Cornelius P. Dullemond; 4. Chemical and isotopic evolution of the solar nebula and protoplanetary disks Dmitry Semenov, Subrata Chakraborty and Mark Thiemens; 5. Laboratory studies of simple dust analogs in astrophysical environments John R. Brucato and Joseph A. Nuth III; 6. Dust composition in protoplanetaty dust Michiel Min and George Flynn; 7. Dust particle size evolution Klaus M. Pontoppidan and Adrian J. Brearly; 8. Thermal processing in protoplanetary nebulae Daniel Apai, Harold C. Connolly Jr. and Dante S. Lauretta; 9. The clearing of protoplanetary disks and of the protosolar nebula Ilaira Pascucci and Shogo Tachibana; 10. Accretion of planetesimals and the formation of rocky planets John E. Chambers, David O'Brien and Andrew M. Davis; Appendixes; Glossary; Index.

  9. Atmospheric dust

    NSDL National Science Digital Library

    University of Utah. Astrophysics Science Project Integrating Research and Education (ASPIRE)

    2003-01-01

    What is the purpose of dust in the atmosphere? On this activity page, part of an interactive laboratory series for grades 8-12, students read about the need for dust in the atmosphere as an agent for condensation. The addition of dust particles to the atmosphere by airplanes introduces students to the concept of cloud seeding and influencing the chance of rain in an area. Copyright 2005 Eisenhower National Clearinghouse

  10. Streptomycetes in house dust: associations with housing characteristics and endotoxin

    EPA Science Inventory

    In addition to mold, indoor bioaerosols also contain bacterial components that may have implications for human health. Endotoxin is a cell wall component in Gram-negative bacteria present at varying levels indoors that has been found to have respiratory health implications. Stre...

  11. Size-resolved dust and aerosol contaminants associated with copper and lead smelting emissions: implications for emission management and human health.

    PubMed

    Csavina, Janae; Taylor, Mark P; Félix, Omar; Rine, Kyle P; Eduardo Sáez, A; Betterton, Eric A

    2014-09-15

    Mining operations, including crushing, grinding, smelting, refining, and tailings management, are a significant source of airborne metal and metalloid contaminants such as As, Pb and other potentially toxic elements. In this work, we show that size-resolved concentrations of As and Pb generally follow a bimodal distribution with the majority of contaminants in the fine size fraction (<1 ?m) around mining activities that include smelting operations at various sites in Australia and Arizona. This evidence suggests that contaminated fine particles (<1 ?m) are the result of vapor condensation and coagulation from smelting operations while coarse particles are most likely the result of windblown dust from contaminated mine tailings and fugitive emissions from crushing and grinding activities. These results on the size distribution of contaminants around mining operations are reported to demonstrate the ubiquitous nature of this phenomenon so that more effective emission management and practices that minimize health risks associated with metal extraction and processing can be developed. PMID:24995641

  12. Atmospheric Dust

    NSDL National Science Digital Library

    Millions of tons of dust are lifted from deserts annually, suspended in the atmosphere, and released to fall on the oceans, but scientists are a long way from understanding the impact of atmospheric dust on the climate and weather systems of Earth or on marine organisms. This radio broadcast explains how the nitrogen, phosphorus and iron released from dust boosts the growth of phytoplankton, which also soak up carbon dioxide and release more gases into the atmosphere. Better monitoring and more sophisticated sensors are giving us a more accurate picture of the dust in the atmosphere; the broadcast reports on investigations of dust from ice cores and on computer simulations of the connections between dust and climate. But the unpredictable nature of dust events makes it extremely difficult to determine their impact on the natural systems of Earth. There are discussions with geographers, oceanographers, environmentalists and climate modelers about atmospheric dust, one of the least understood and most contradictory components of the atmosphere. The broadcast is 28 minutes in length.

  13. China Dust

    Atmospheric Science Data Center

    2013-04-16

    ... SpectroRadiometer (MISR) nadir-camera images of eastern China compare a somewhat hazy summer view from July 9, 2000 (left) with a ... arid and sparsely vegetated surfaces of Mongolia and western China pick up large quantities of yellow dust. Airborne dust clouds from the ...

  14. Eliminating Lead Poisoning

    E-print Network

    Eliminating Childhood Lead Poisoning: A Federal Strategy Targeting Lead Paint Hazards President Poisoning: A Federal Strategy Targeting Lead Paint Hazards February 2000 President`s Task Force was that the lead paint, dust and soil in and around our treasured home was the culprit. Worse yet, a month later

  15. Fms-Like Tyrosine Kinase 3 Ligand Decreases T Helper Type 17 Cells and Suppressors of Cytokine Signaling Proteins in the Lung of House Dust Mite–Sensitized and –Challenged Mice

    PubMed Central

    McGee, Halvor S.; Stallworth, Arthur L.; Agrawal, Tanupriya; Shao, Zhifei; Lorence, Lindsey; Agrawal, Devendra K.

    2010-01-01

    We previously reported that Fms-like tyrosine kinase 3 ligand (Flt3-L) reversed airway hyperresponsiveness (AHR) and airway inflammation, and increased the number of regulatory CD11chighCD8?highCD11blow dendritic cells and CD4+CD25+ICOS+Foxp3+IL-10+ T-regulatory cells in the lung of allergen-sensitized and -challenged mice. In this study, we evaluated the effect of Flt3-L on Th17 cells and expression of suppressors of cytokine signaling (SOCS) proteins in the lungs of house dust mite (HDM)–sensitized and –challenged mice. BALB/c mice were sensitized and challenged with HDM, and AHR to methacholine was established. Mice were treated with Flt3-L (5 ?g, intraperitoneal) daily for 10 days. Levels of IL-4, -5, -6, -8, and -13, and transforming growth factor (TGF)–? in the bronchoalveolar lavage fluid (BALF) were examined by ELISA. Flt3-L treatment reversed existing AHR to methacholine and substantially decreased eosinophils, neutrophils, IL-5, -6, -8, and IL-13, and TGF-? levels in the BALF. HDM-sensitized and -challenged mice showed a significant increase in lung CD4+IL-17+IL-23R+CD25? T cells with high expression of retinoic acid–related orphan receptor (ROR)–?t transcripts. However, administration of Flt3-L substantially decreased the number of lung CD4+IL-17+IL-23R+CD25? T cells, with significantly decreased expression of ROR-?t mRNA in these cells. HDM sensitization caused a significant increase in the expression of SOCS-1, -3, and -5 in the lung. Flt3-L treatment abolished the increase in SOCS-1 and SOCS-3 proteins, whereas SOCS-5 expression was significantly reduced. These data suggest that the therapeutic effect of Flt3-L in reversing the hallmarks of allergic asthma in a mouse model is mediated by decreasing IL-6 and TGF-? levels in the BALF, which, in turn, decrease CD4+IL-17+IL-23R+ROR-?t+CD25? T cells and the expression of SOCS-1 and SOCS-3 in the lung of HDM-sensitized and -challenged mice. PMID:19933379

  16. Determination of numbers of lead-exposed American children as a function of lead source: Integrated summary of a report to the US Congress on childhood lead poisoning

    SciTech Connect

    Mushak, P.; Crocetti, A.F. (Univ. of North Carolina, Chapel Hill (USA))

    1989-12-01

    In 1986, the U.S. Congress (Section 118(f), Superfund Amendments and Reauthorization Act (SARA)) directed the Agency for Toxic Substances and Disease Registry to provide to it a quantitative assessment of the contributions of various sources of lead to childhood exposure. We provided both a quantitative response to the mandate and a critique of low-level lead sources for U.S. population segments. We also present here an integrated assessment of major and low-level lead sources. Significant sources of lead in childhood exposure include lead in paint, dust, soil, and drinking water. Approximately 6 million U.S. children less than 7 years old reside in the oldest housing, with highest exposure risk due to leaded paint. About 2 million in deteriorated units are at particularly high risk for exposure with ca. 1.2 million children in oldest, deteriorated housing estimated to have blood lead (PbB) levels above 15 micrograms/dl. Soil and dust lead are potential sources of exposure for 6-12 million children. Residential tap water lead is a measurable source for ca. 3.8 million children, of whom the U.S. EPA estimates ca. 240,000 have water-specific exposures at toxic levels. Leaded gasoline combustion mainly in past years has produced, and will continue to produce into the 1990s, significant numbers of exposed children with toxicologically elevated PbBs. For 1990, 1.25 million children will have their PbBs fall below 15 micrograms/dl. Food lead can cause significant exposure in certain cases.36 references.

  17. Where Is Lead Found? Paint in many homes built before 1978 may contain lead.

    E-print Network

    Liskiewicz, Maciej

    Where Is Lead Found? · Paint in many homes built before 1978 may contain lead. · Soil surrounding a home may have lead from exterior paint dust or from leaded gasoline in cars. · Household dust can contain lead from deteriorating lead- based paint or from soil containing lead that is tracked

  18. Environmental Health Disparities in Housing

    PubMed Central

    2011-01-01

    The physical infrastructure and housing make human interaction possible and provide shelter. How well that infrastructure performs and which groups it serves have important implications for social equity and health. Populations in inadequate housing are more likely to have environmental diseases and injuries. Substantial disparities in housing have remained largely unchanged. Approximately 2.6 million (7.5%) non-Hispanic Blacks and 5.9 million Whites (2.8%) live in substandard housing. Segregation, lack of housing mobility, and homelessness are all associated with adverse health outcomes. Yet the experience with childhood lead poisoning in the United States has shown that housing-related disparities can be reduced. Effective interventions should be implemented to reduce environmental health disparities related to housing. PMID:21551378

  19. Working towards accreditation by the International Standards Organization 15189 Standard: how to validate an in-house developed method an example of lead determination in whole blood by electrothermal atomic absorption spectrometry.

    PubMed

    Garcia Hejl, Carine; Ramirez, Jose Manuel; Vest, Philippe; Chianea, Denis; Renard, Christophe

    2014-09-01

    Laboratories working towards accreditation by the International Standards Organization (ISO) 15189 standard are required to demonstrate the validity of their analytical methods. The different guidelines set by various accreditation organizations make it difficult to provide objective evidence that an in-house method is fit for the intended purpose. Besides, the required performance characteristics tests and acceptance criteria are not always detailed. The laboratory must choose the most suitable validation protocol and set the acceptance criteria. Therefore, we propose a validation protocol to evaluate the performance of an in-house method. As an example, we validated the process for the detection and quantification of lead in whole blood by electrothermal absorption spectrometry. The fundamental parameters tested were, selectivity, calibration model, precision, accuracy (and uncertainty of measurement), contamination, stability of the sample, reference interval, and analytical interference. We have developed a protocol that has been applied successfully to quantify lead in whole blood by electrothermal atomic absorption spectrometry (ETAAS). In particular, our method is selective, linear, accurate, and precise, making it suitable for use in routine diagnostics. PMID:25187889

  20. Working Towards Accreditation by the International Standards Organization 15189 Standard: How to Validate an In-house Developed Method an Example of Lead Determination in Whole Blood by Electrothermal Atomic Absorption Spectrometry

    PubMed Central

    Ramirez, Jose Manuel; Vest, Philippe; Chianea, Denis; Renard, Christophe

    2014-01-01

    Laboratories working towards accreditation by the International Standards Organization (ISO) 15189 standard are required to demonstrate the validity of their analytical methods. The different guidelines set by various accreditation organizations make it difficult to provide objective evidence that an in-house method is fit for the intended purpose. Besides, the required performance characteristics tests and acceptance criteria are not always detailed. The laboratory must choose the most suitable validation protocol and set the acceptance criteria. Therefore, we propose a validation protocol to evaluate the performance of an in-house method. As an example, we validated the process for the detection and quantification of lead in whole blood by electrothermal absorption spectrometry. The fundamental parameters tested were, selectivity, calibration model, precision, accuracy (and uncertainty of measurement), contamination, stability of the sample, reference interval, and analytical interference. We have developed a protocol that has been applied successfully to quantify lead in whole blood by electrothermal atomic absorption spectrometry (ETAAS). In particular, our method is selective, linear, accurate, and precise, making it suitable for use in routine diagnostics. PMID:25187889

  1. Animal House

    NSDL National Science Digital Library

    2014-03-10

    The goal of this activity is to design, build and test a house or toy for an animal. Learners will research a particular animal and design a house or toy that will encourage that animal's specific behaviors. Each house or toy must fit into the animal's cage, support the animal's size and weight, and be constructed of non-toxic materials. Safety note: adult supervision recommended for cutting cardboard boxes.

  2. Addressing Lead-Based Paint Hazards During Renovation, Remodeling, and Rehabilitation in Federally Owned and Assisted Housing. Student Manual for Use in HUD-Sponsored Lead-Safe Work Practices Training.

    ERIC Educational Resources Information Center

    Department of Housing and Urban Development, Washington, DC.

    This student manual comprises the United States Environmental Protection Agency's model renovation training course designed for renovation, remodeling, and painting contractors. It provides information regarding the containment, minimization, and cleanup of lead hazards during activities that disturb lead painted surfaces. Introductory material…

  3. AMERICAN HOUSING SURVEY

    EPA Science Inventory

    The American Housing Survey (AHS) collects data on the Nation's housing, including apartments, single-family homes, mobile homes, vacant housing units, household characteristics, income, housing and neighborhood quality, housing costs, equipment and fuels, size of housing unit, a...

  4. Optical characteristics of desert dust

    NASA Astrophysics Data System (ADS)

    Walker, Philip L.; Blomshield, Fred

    2002-08-01

    We have been conducting research aimed at enabling prediction of desert optical environments from meteorological and satellite observations. To this end we have been collecting aerosol size distributions, visibility and meteorological data continuously for the past year at 2 sites in the Mojave Desert of California. Optical properties of dust are calculated from these data for a great variety of meteorological conditions. The concentration of dust particles is strongly dependent on wind speed for speeds greater than a threshold (7 m/s at Edwards and 15 m/s at China Lake). For individual wind episodes there is a clear relationship between wind speed and dust mass. However, that relationship changes from event to event leading to noisy summary plots; thus, indicating that other factors, such as dust sources, also influence dust loading. The HYPACT program is used to map out the sources, concentration and flow of dust. HYPACT is a pollution transport program that uses RAMS meteorological code output for input. HYPACT can calculate concentration forward in time from an assumed emission source or backward in time from an observation site. This facilitates the location of dust sources and the calculation of dust concentrations along air streams. Once dust concentrations are known and assuming the particle size distributions are the same as at the measurement sites knowledge of IR extinction is no longer confined to just the measurement sites.

  5. From Dust to Protoplanets

    NASA Astrophysics Data System (ADS)

    Chambers, John E.

    2014-11-01

    To date, most simulations of planetary accretion have considered a single stage of growth such as dust coagulation, planetesimal formation, or oligarchic growth. However, these stages are likely to take place concurrently in different regions of a protoplanetary disk, and even at the same location in a disk. This can lead to interactions and feedbacks between the various growth stages, altering the outcome. Here I will present results of new simulations that model growth from micrometer-size dust grains up to planetary embryos throughout a protoplanetary disk, including potentially important physical processes such as radial drift,bouncing and fragmentation during collisions, and pebble accretion onto large bodies. I will also discuss the implications for giant-planet formation, dust retention in protoplanetary disks, and meteorite parent body ages and compositions.

  6. Dust Catchers

    NSDL National Science Digital Library

    2014-08-07

    In this activity related to indoor air pollution, learners build take-home dust catchers with wax paper and petroleum jelly. After a set monitoring period, learners conduct representative particle counts using a comparison grid. Learners will also graph the results. This activity can be enhanced by sharing the "Health Hazards of Lunar Dust" Podcast with learners (see related resource link). This resource includes background information, variation ideas and a handout for learners in both English and Spanish.

  7. Clay Houses

    ERIC Educational Resources Information Center

    Pedro, Cathy

    2011-01-01

    In this article, the author describes a project designed for fourth-graders that involves making clay relief sculptures of houses. Knowing the clay houses will become a family heirloom makes this lesson even more worth the time. It takes three classes to plan and form the clay, and another two to underglaze and glaze the final products.

  8. New wall system keeps the lead out and the heat in.

    SciTech Connect

    Cavallo, J. D.; Wendt, R.; Decision and Information Sciences; ORNL

    1997-11-01

    The presence of lead-based paint in older multifamily housing is a major public health concern. Dealing with these lead hazards offers opportunities for improving not only the health of the occupants but also the energy performance of the units, particularly when such efforts are combined with energy conservation measures such as energy-efficient windows and other building envelope improvements. A new composite wall system developed by Oak Ridge and Argonne National Laboratories restricts movement of lead dust and improves energy efficiency--and at a lower cost than traditional framed walls.

  9. Solar House

    NSDL National Science Digital Library

    Wendy Van Norden

    In this activity students work in teams to design and build a model of a solar house after researching several websites. Students will discover that a solar house takes advantage of solar energy to minimize the use of traditional energy sources and can include design elements that take advantage of the sun's rays to light and heat the house, to heat water, and to set up a favorable flow of air. They also learn that many solar houses contain a solar mass that will absorb the heat during the day and release it slowly at night and a passive solar house will also take into account the angle of the sun's rays, to maximize heating during the winter and shade during the summer. This site contains all of the specifications for planning, building, and testing the model and a rubric for grading the project.

  10. Impact of a More Stringent Blood Lead Level Recommendation for Children (Ages 1-5): Vulnerabilities Related to Housing, Food Security, Vitamins, and Environmental Toxicants

    EPA Science Inventory

    The adverse health effects of lead (Pb) exposure in young children are well known. Non-Hispanic black children historically have higher blood Pb levels (BLL) compared to Mexican-Americans and non- Hispanic white children (CDC-MMWR). In the past, BLL tests below 10 µg/dL m...

  11. HOUSING DESCRIPTIONS COMMERCIALLY AVAILABLE HOUSING

    E-print Network

    Mathis, Wayne N.

    HOUSING DESCRIPTIONS COMMERCIALLY AVAILABLE HOUSING: Polyester Film Enclosures: Enclosures can come in many formats, including L-weld, match-book wrap, and pockets. Although polyester film enclosures polyester film enclosure flagged as a set. If the staple is secure and not rusty, leave it in place. Note

  12. 21. INTERIOR VIEW OF SIXTH FLOOR OF MILL HOUSE, SHOWING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    21. INTERIOR VIEW OF SIXTH FLOOR OF MILL HOUSE, SHOWING BLOWER AT RIGHT AND DUST CONTROL FILTER SYSTEM AT LEFT, LOOKING SOUTHEAST - Sperry Corn Elevator Complex, Weber Avenue (North side), West of Edison Street, Stockton, San Joaquin County, CA

  13. Housing Policy

    NSDL National Science Digital Library

    2012-04-20

    Understanding the variegated terrain of local and state housing policies is key for urban planners, geographers, and others with an interest in the built environment and public policy. This site was created by the Center for Housing Policy (the research affiliate of the National Housing Conference) in order to provide information for "expanding the availability of homes for working families and others in your community." The site was launched in 2008, and includes sections such as Toolbox, Building a Strategy, and Forum. The Getting Started area provides answers to basic questions such as "What is 'affordable housing'?" and "What is 'subsidized housing'?" Moving on, the Toolbox area includes documents and summaries on specific policy tools designed for a variety of reasons, from meeting the housing needs of older adults to improving residential energy efficiency. Visitors won't want to miss the Building a Strategy area. Here they will find information about how to create a successful housing strategy that will provide residential units for a range of community members.

  14. Things you can do 5to help lower your child's lead level.

    E-print Network

    lead poisoning from lead paint in homes built before 1978. It is important to find and fix lead in your or renovate until your home has been inspected for lead. Home repairs like sanding or scraping paint can make dangerous lead dust. #12;3 Clean up lead dust. When old paint cracks and peels, it makes lead dust. Lead

  15. [Biological effect of wood dust].

    PubMed

    Maciejewska, A; Wojtczak, J; Bielichowska-Cybula, G; Doma?ska, A; Dutkiewicz, J; Mo?ocznik, A

    1993-01-01

    The biological effect of exposure to wood dust depends on its composition and the content of microorganisms which are an inherent element of the dust. The irritant and allergic effects of wood dust have been recognised for a long time. The allergic effect is caused by the wood dust of subtropical trees, e.g. western red cedar (Thuja plicata), redwood (Sequoia sempervirens), obeche (Triplochiton scleroxylon), cocabolla (Dalbergia retusa) and others. Trees growing in the European climate such as: larch (Larix), walnut (Juglans regia), oak (Quercus), beech (Fagus), pine (Pinus) cause a little less pronounced allergic effect. Occupational exposure to irritative or allergic wood dust may lead to bronchial asthma, rhinitis, alveolitis allergica, DDTS (Organic dust toxic syndrome), bronchitis, allergic dermatitis, conjunctivitis. An increased risk of adenocarcinoma of the sinonasal cavity is an important and serious problem associated with occupational exposure to wood dust. Adenocarcinoma constitutes about half of the total number of cancers induced by wood dust. An increased incidence of the squamous cell cancers can also be observed. The highest risk of cancer applies to workers of the furniture industry, particularly those dealing with machine wood processing, cabinet making and carpentry. The cancer of the upper respiratory tract develops after exposure to many kinds of wood dust. However, the wood dust of oak and beech seems to be most carcinogenic. It is assumed that exposure to wood dust can cause an increased incidence of other cancers, especially lung cancer and Hodgkin's disease. The adverse effects of microorganisms, mainly mould fungi and their metabolic products are manifested by alveolitis allergica and ODTS. These microorganisms can induce aspergillomycosis, bronchial asthma, rhinitis and allergic dermatitis. PMID:8231799

  16. DEVELOPMENT OF A HIGH VOLUME SURFACE SAMPLER FOR PESTICIDES IN FLOOR DUST

    EPA Science Inventory

    A high volume surface sampler (HVS2) for the collection of house dust and the semivolatile organics (including pesticides) in house dust has been designed and tested. The sampler consists of an intake nozzle, cyclone, and filter. The position of the nozzle is regulated by the sta...

  17. ANALYSIS OF SOIL AND DUST SAMPLES FOR POLYCHLORINATED BIPHENYLS BY ENZYME LINKED IMMUNOSORBENT ASSAY (ELISA)

    EPA Science Inventory

    An inhibition enzyme-linked immunosorbent assay (ELISA) was used to determine polychlorinated biphenyls (PCBs) in house dust and soil. Soil and house dust samples were analyzed for PCB by both gas chromatography/electron capture detection (GC/ECD) and ELISA methods. A correlati...

  18. EAP Reciprocity Housing Information International House

    E-print Network

    California at San Diego, University of

    EAP Reciprocity Housing Information International House Most EAP students choose to apply to live in the International House (http:// ihouse.ucsd.edu/), an on-campus living/learning community which is dedicated apply to the I-House program. The I-House application deadline is June 16, 2010. Other On-Campus Housing

  19. Arctic house

    E-print Network

    Turkel, Joel A. (Joel Abram), 1969-

    1999-01-01

    Currently available housing in the Arctic is limited to solutions that have been adapted from designs for less severe climates. This thesis has developed a new manner of residential construction designed specifically for ...

  20. House Warming

    NSDL National Science Digital Library

    2014-01-27

    In this physical sciences activity, learners explore how passive solar design increases energy efficiency. Learners test paperboard models of different building designs to discover how the design affects the amount of heat that enters the house.

  1. Pesticide loadings of select organophosphate and pyrethroid pesticides in urban public housing

    Microsoft Academic Search

    Rhona Julien; Gary Adamkiewicz; Jonathan I. Levy; Deborah Bennett; Marcia Nishioka; John D. Spengler

    2008-01-01

    We investigated the magnitude and distribution of pyrethroid and organophosphate pesticide loadings within public housing dwellings in Boston, Massachusetts and compared the results using various sampling methods. We collected dust matrices from living room and kitchen in 42 apartments and analyzed for eleven pyrethoids (e.g., permethrin and cyfluthrin) and two organophosphates (chlorpyrifos and diazinon) in house dust using GC\\/MS. Agreement

  2. Brookhaven House

    SciTech Connect

    Not Available

    1981-08-01

    The Brookhaven House is an energy conserving residence that employs thermal mass walls, a modified Trombe wall, a sunspace, and extensive weatherization. The principles of heat storage in thermal mass are briefly explained and siting of the house is discussed. Naturally circulated hot air from a central furnace, and a wood stove contribute to the heating requirements. Floor plans, elevations and sections are provided. (LEW)

  3. 3. Credit PSR. View looks east (100°) down dust ditch ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Credit PSR. View looks east (100°) down dust ditch near Fourth and B Streets in "the loop." In background are Building 4505, Building 4500 (Control Tower) and Building 4456 (Fire House No. 4). - Edwards Air Force Base, North Base, Dust Ditch System, Traversing North Base, Boron, Kern County, CA

  4. Dust mites living in human lungs – the cause of asthma?

    Microsoft Academic Search

    H van Woerden

    2004-01-01

    Asthma does not have a clear cause and may represent a cluster of diseases. We propose that asthma in house dust mite sensitive patients may be caused by recurrent inhalation of live dust mites which are able to live for some time in the bronchioles of the lung. To provide themselves with a food source, the mites may purposefully excrete

  5. Contrasting Immunological Effects of Two Disparate Dusts – Preliminary Observations

    Microsoft Academic Search

    Harri Alenius; Jaakko Pakarinen; Ossian Saris; Maria A. Andersson; Marina Leino; Kristiina Sirola; Marja-Leena Majuri; Jari Niemelä; Sampsa Matikainen; Henrik Wolff; Leena von Hertzen; Mika Mäkelä; Tari Haahtela; Mirja Salkinoja-Salonen

    2009-01-01

    Background: Modern lifestyle and urbanization have been associated with a raised risk for atopic diseases whereas early and long-term exposure to a farm environment confers protection against atopic sensitization. Immunomodulatory potential and microbiological characteristics of settled airborne dust from an urban house and a barn were examined. Methods: Pulmonary inflammation was induced in mice by repeated intranasal administration of dusts.

  6. Contributions of Paint and Soil to Pb in Household Dust Wipes: An XAS Study

    NASA Astrophysics Data System (ADS)

    Pingitore, N. E.; Clague, J. W.; Amaya, M. A.

    2010-12-01

    Speciation of Pb by X-ray absorption spectroscopy (XAS) indicated that Pb compounds associated with lead-based paint accounted for perhaps half of the Pb in 24 household dust wipes collected in El Paso, Texas. Soil-derived, sorbed Pb, likely Pb-humate, was also a major Pb species in many of the dust wipes. Household dust wipes are a standard technique for evaluating health risks of Pb to children, particularly toddlers, in public and private housing. The level of Pb in the wipes does not, however, indicate whether the source of the Pb is the house itself (peeling or powdering interior or exterior paint) or external, from contaminated soil or airborne particulate matter brought into the house by wind or foot traction. Understanding the origin of Pb in household dust is important in remediation: cover the old paint or remove the yard soil. XAS speciation can assist in understanding the source of Pb in household dust. The presence of significant Pb-humate requires a soil source, and suggests the need for soil remediation. Such species of Pb as hydrocerussite, lead sulfate, lead silicate, and lead chromate can be presumed to be components of lead-based paint. These may represent interior and/or exterior paint and thus do not uniquely identify the locus of the Pb source(s). Pb L-III edge XAFS data were collected on beam lines 7-3, 10-2, and 11-2 at SSRL at typical conditions of 3 GeV field and 80-200 mA current, using Si(220) water- or liquid-nitrogen-cooled monochromator crystals. Data were collected at ambient temperature in fluorescence mode using a 13- or 30-element Ge detector with a Se 3 or 6 filter and Soller slits to reduce scattered radiation. This publication was made possible by grant numbers 1RO1-ES11367 and 1 S11 ES013339-01A1 from the National Institute of Environmental Health Sciences (NIEHS), NIH. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the NIEHS, NIH. Portions of this research were carried out at the Stanford Synchrotron Radiation Lightsource, a national user facility operated by Stanford University on behalf of the U.S. Department of Energy, Office of Basic Energy Sciences.

  7. Blood lead—Tooth lead relationship among Boston children

    Microsoft Academic Search

    Michael B. Rabinowitz; Alan Leviton; David C. Bellinger

    1989-01-01

    The amount of lead in deciduous teeth has been used extensively as a marker for infant lead exposure and body burden. Elevated tooth lead levels have been seen in children who had lead poisoning. Also, on a population wide basis tooth lead levels appear to vary according to housing status and presumably lead exposure. This exposure index has been applied

  8. Comet Gas and Dust Dynamics Modeling

    NASA Technical Reports Server (NTRS)

    Von Allmen, Paul A.; Lee, Seungwon

    2010-01-01

    This software models the gas and dust dynamics of comet coma (the head region of a comet) in order to support the Microwave Instrument for Rosetta Orbiter (MIRO) project. MIRO will study the evolution of the comet 67P/Churyumov-Gerasimenko's coma system. The instrument will measure surface temperature, gas-production rates and relative abundances, and velocity and excitation temperatures of each species along with their spatial temporal variability. This software will use these measurements to improve the understanding of coma dynamics. The modeling tool solves the equation of motion of a dust particle, the energy balance equation of the dust particle, the continuity equation for the dust and gas flow, and the dust and gas mixture energy equation. By solving these equations numerically, the software calculates the temperature and velocity of gas and dust as a function of time for a given initial gas and dust production rate, and a dust characteristic parameter that measures the ability of a dust particle to adjust its velocity to the local gas velocity. The software is written in a modular manner, thereby allowing the addition of more dynamics equations as needed. All of the numerical algorithms are added in-house and no third-party libraries are used.

  9. Characterization of jovian plasma embedded dust particles

    E-print Network

    Amara L. Graps

    2006-09-12

    As the data from space missions and laboratories improve, a research domain combining plasmas and charged dust is gaining in prominence. Our solar system provides many natural laboratories such as planetary rings, comet comae and tails, ejecta clouds around moons and asteroids, and Earth's noctilucent clouds for which to closely study plasma-embedded cosmic dust. One natural laboratory to study electromagnetically-controlled cosmic dust has been provided by the Jovian dust streams and the data from the instruments which were on board the Galileo spacecraft. Given the prodigious quantity of dust poured into the Jovian magnetosphere by Io and its volcanoes resulting in the dust streams, the possibility of dusty plasma conditions exist. This paper characterizes the main parameters for those interested in studying dust embedded in a plasma with a focus on the Jupiter environment. I show how to distinguish between dust-in-plasma and dusty-plasma and how the Havnes parameter P can be used to support or negate the possibility of collective behavior of the dusty plasma. The result of applying these tools to the Jovian dust streams reveals mostly dust-in-plasma behavior. In the orbits displaying the highest dust stream fluxes, portions of orbits E4, G7, G8, C21 satisfy the minimum requirements for a dusty plasma. However, the P parameter demonstrates that these mild dusty plasma conditions do not lead to collective behavior of the dust stream particles.

  10. Fractionation and Biotoxicity of Heavy Metals in Urban Dusts Collected from Hong Kong and London

    Microsoft Academic Search

    W. H Wang; M. H. Wong; S. Leharne; B. Fisher

    1998-01-01

    Samples of urban dusts, road site dusts and car park dusts, were collected at two selected sites each in Hong Kong and London. Sequential extraction was used to characterise the chemical compositions of these urban dusts. Copper, lead, zinc, pH, electrical conductivity and organic content were measured. Biotoxicity tests of urban dusts were conducted on higher plants (Brassica chinensis and

  11. NHEXAS PHASE I REGION 5 STUDY--STANDARD OPERATING PROCEDURE--DUST SAMPLING WORKPLAN (RTI/ACS-AP-209-020)

    EPA Science Inventory

    This procedure describes the work plan for collecting house dust samples. Wipe samples were collected to determine the concentrations (ug/g) and loadings (ug/cm2) of trace metals in house dust. The selection of the surfaces from which dust was collected was based upon the availab...

  12. Dust cyclone technology for gins – A literature review

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dust cyclone research leading to more efficient designs has helped the cotton ginning industry to comply with increasingly stringent air quality regulations governing fine particulate emissions. Future changes in regulations may require additional improvements in dust cyclone efficacy. This inter-...

  13. California Dust

    Atmospheric Science Data Center

    2014-05-15

    ... and winter when a high pressure system forms in the Great Basin between the Sierra Nevadas and the Rocky Mountains. The air warms as it ... camera's oblique viewing angle. Southeast of the Los Angeles Basin, a swirl of dust, probably blown through the Banning Pass, curves toward ...

  14. Sahara Dust

    Atmospheric Science Data Center

    2013-04-15

    ... productivity, and human health. MISR images the Earth by measuring the spatial patterns of reflected sunlight. In the upper ... cirrus clouds cast shadows on the underlying ocean and dust layer, which are visible in shades of blue and tan, respectively. In the lower ...

  15. Environmental chemicals mediated the effect of old housing on adult health problems: US NHANES, 2009-2010.

    PubMed

    Shiue, Ivy; Bramley, Glen

    2015-01-01

    Housing conditions affect occupants continuously, and health interventions have shown a positive association between housing investment or improvement and occupant's health. However, the sources of the housing problems were less understood. Since it was observed that lead dust and chloroanisoles released from housing (materials) as indoor pollutants affected child's health, we now aimed to examine the relationships among built year, environmental chemicals and individual health in adults in a national and population-based setting. Data were retrieved from the US National Health and Nutrition Examination Survey, 2009-2010, including demographics, housing characteristics, self-reported health status, biomarkers and blood and urinary chemical concentrations. Adults aged 20 and above were included for statistical analysis (n?=?5,793). Analysis involved chi-square test, t test, and survey-weighted general linear regression and logistic regression modelling. People who resided in older housing built before 1990 tended to report chronic bronchitis, liver problems, stroke, heart failure, diabetes, asthma and emphysema. Higher values in HDL cholesterol, blood lead and blood cadmium and having positive responses of hepatitis A, B, C and E antibodies among occupants were also observed. Furthermore, higher environmental chemical concentrations related to old housing including urinary cadmium, cobalt, platinum, mercury, 2,5-dichlorophenol and 2,4-dichlorophenol concentrations and mono-cyclohexyl phthalate and mono-isobutyl phthalate metabolites were shown in occupants as well. Older housing (?30 years) seemed to contribute to the amount of environmental chemicals that affected human health. Regular monitoring, upgrading and renovation of housing to remove environmental chemicals and policy to support people in deprived situations against environmental injustice would be needed. PMID:25138559

  16. Can dust destabilize galactic disks?

    E-print Network

    Ch. Theis; N. Orlova

    2004-03-16

    We studied the dynamical influence of a dust component on the gaseous phase in central regions of galactic disks. Therefore, we performed two-dimensional hydrodynamical simulations for flat multi-component disks embedded in a stellar and dark matter potential. The pressure-free dust component is coupled to the gas by a drag force depending on their velocity difference. It turned out that the most unstable regions are those with either a low or near to minimum Toomre parameter or with rigid rotation, i.e. the central area. In that regions the dust-free disks become most unstable for a small range of high azimuthal modes (m \\sim 8), whereas in dusty disks all modes have similar amplitudes resulting in a patchy appearance. The structures in the dust have a larger contrast between arm and inter-arm regions than those of the gas. The dust peaks are frequently correlated with peaks of the gas distribution, but they do not necessarily coincide with them. This leads to a large scatter in the dust-to-gas ratios. The appearance of the dust is more cellular (i.e. sometimes connecting different spiral features), whereas the gas is organized in a multi-armed spiral structure. We found that an admixture of 2% dust (relative to the mass of the gas) destabilizes gaseous disks substantially, whereas dust-to-gas ratios below 1% have no influence on the evolution of the gaseous disk. For a high dust-to-gas ratio of 10% the instabilities reach the saturation level already after 30 Myr.

  17. BIOAVAILABILITY AND BIOLOGICAL RESPONSE OF PBDES ADMINISTERED TO RATS IN HOUSEHOLD DUST

    EPA Science Inventory

    Abstract Household dust has recently been implicated as a source of PBDE exposure. This study investigated the bioavailability of PBDEs in house dust administered through the diet as compared to PBDEs in oil via the diet. PBDEs in household dust were just as bioavailabl...

  18. NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE FOR EXTRACTION OF SOIL AND HOUSE DUST SAMPLES FOR GC/MS ANALYSIS OF PESTICIDE AND PAH (BCO-L-28.0)

    EPA Science Inventory

    The purpose of this SOP is to describe procedures for extracting and preparing a dust or soil sample for gas chromatography mass spectrometry (GC/MS) analysis of pesticides and polyaromatic hydrocarbons (PAHs). This procedure was followed to ensure consistent data retrieval durin...

  19. NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE FOR EXTRACTION OF SOIL/HOUSE DUST FOR GC/MS ANALYSIS OF PESTICIDES (BCO-L-14.0)

    EPA Science Inventory

    The purpose of this SOP is to describe procedures for extracting and preparing dust or soil samples for gas chromatography/mass spectrometry (GC/MS) analysis of pesticides. This procedure was followed to ensure consistent data retrieval during the Arizona NHEXAS project and the "...

  20. Falmer Sports Falmer House

    E-print Network

    Sussex, University of

    Bramber House Fulton Mantell Falmer Sports Complex CISC Hastings Shawcross Meeting House Falmer House Library Square Sussex House BSMS Spo ts Centre r ACCA Library IDS Centre Sussex Innovation 21 Ashdown House 42 Attenborough Centre 56 Boiler House 31 Bramber House (under construction) 13 BSMS

  1. Interactive Soil Dust Aerosol Model in the GISS GCM. Part 1; Sensitivity of the Soil Dust Cycle to Radiative Properties of Soil Dust Aerosols

    NASA Technical Reports Server (NTRS)

    Perlwitz, Jan; Tegen, Ina; Miller, Ron L.

    2000-01-01

    The sensitivity of the soil dust aerosol cycle to the radiative forcing by soil dust aerosols is studied. Four experiments with the NASA/GISS atmospheric general circulation model, which includes a soil dust aerosol model, are compared, all using a prescribed climatological sea surface temperature as lower boundary condition. In one experiment, dust is included as dynamic tracer only (without interacting with radiation), whereas dust interacts with radiation in the other simulations. Although the single scattering albedo of dust particles is prescribed to be globally uniform in the experiments with radiatively active dust, a different single scattering albedo is used in those experiments to estimate whether regional variations in dust optical properties, corresponding to variations in mineralogical composition among different source regions, are important for the soil dust cycle and the climate state. On a global scale, the radiative forcing by dust generally causes a reduction in the atmospheric dust load corresponding to a decreased dust source flux. That is, there is a negative feedback in the climate system due to the radiative effect of dust. The dust source flux and its changes were analyzed in more detail for the main dust source regions. This analysis shows that the reduction varies both with the season and with the single scattering albedo of the dust particles. By examining the correlation with the surface wind, it was found that the dust emission from the Saharan/Sahelian source region and from the Arabian peninsula, along with the sensitivity of the emission to the single scattering albedo of dust particles, are related to large scale circulation patterns, in particular to the trade winds during Northern Hemisphere winter and to the Indian monsoon circulation during summer. In the other regions, such relations to the large scale circulation were not found. There, the dependence of dust deflation to radiative forcing by dust particles is probably dominated by physical processes with short time scales. The experiments show that dust radiative forcing can lead to significant changes both in the soil dust cycle and in the climate state. To estimate dust concentration and radiative forcing by dust more accurately, dust size distributions and dust single scattering albedo in the model should be a function of the source region, because dust concentration and climate response to dust radiative forcing are sensitive to dust radiative parameters.

  2. Star dust.

    PubMed

    Ney, E P

    1977-02-11

    Infrared astronomy has shown that certain classes of stars are abundant producers of refractory grains, which condense in their atmospheres and are blown into interstellar space by the radiation pressure of these stars. Metallic silicates of the kind that produce terrestrial planets are injected by the oxygen-rich stars and carbon and its refractories by carbon stars. Much of the interstellar dust may be produced by this mechanism. A number of "infrared stars" are completely surrounded by their own dust, and a few of these exhibit a unique morphology that suggests the formation of a planetary system or a stage in the evolution of a planetary nebula. Certain novae also condense grains, which are blown out in their shells. In our own solar system, comets are found to contain the same silicates that are present elsewhere in the galaxy, suggesting that these constituents were present in the primeval solar nebula. PMID:17732279

  3. Electrodynamics of Martian Dust Disturbances

    NASA Astrophysics Data System (ADS)

    Barth, E. L.; Rafkin, S. C.; Farrell, W.

    2009-12-01

    Recently, it has been suggested that strong electric fields within dust storms may dissociate CO2, leading to a cascade of reactions ending in the production of superoxides, including H2O2, which quickly destroy organics such as methane. The recent microwave detection of a lightning signature on Mars suggests that such strong E-M fields are present there. Triboelectric dust charging physics via the Macroscopic Triboelectric Simulation (MTS) code has been added to the Mars Regional Atmospheric Modeling System (MRAMS) in order to simulate the electrodynamics of dust devils and dust disturbances on Mars. Using the model, we explore how macroscopic electric fields are generated within storms and attempt to quantify the time evolution of the electrodynamical system.

  4. 24 CFR 891.325 - Lead-based paint requirements.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...HOUSING FOR THE ELDERLY PROGRAM AND SECTION 811 SUPPORTIVE...HOUSING FOR PERSONS WITH DISABILITIES PROGRAM) SUPPORTIVE HOUSING...ELDERLY AND PERSONS WITH DISABILITIES Section 811 Supportive...4821-4846), the Residential Lead-Based...

  5. Yinyutang House

    E-print Network

    Hacker, Randi; Boyd, David

    2011-08-21

    furnishings--was shipped here to the Peabody Essex Museum and meticulously reassembled. Even a single chopstick was packed, unpacked and wedged into its original place between a column and a wall. Apparently, a house divided can stand. #boyd #ceas #china...

  6. Possible influence of dust on hurricane genesis

    NASA Astrophysics Data System (ADS)

    Bretl, Sebastian; Reutter, Philipp; Raible, Christoph C.; Ferrachat, Sylvaine; Lohmann, Ulrike

    2014-05-01

    Tropical Cyclones (TCs) belong to the most extreme events in nature. In the past decade, the possible impact of dust on Atlantic hurricanes receives growing interest. As mineral dust is able to absorb incoming solar radiation and therefore warm the surrounding air, the presence of dust can lead to a reduction of sea surface temperature (SST) and an increase in atmospheric stability. Furthermore, resulting baroclinic effects and the dry Saharan easterly jet lead to an enhanced vertical shear of the horizontal winds. SST, stability, moisture and vertical wind shear are known to potentially impact hurricane activity. But how Saharan dust influences these prerequisites for hurricane formation is not yet clear. Some dynamical mechanisms induced by the SAL might even strengthen hurricanes. An adequate framework for investigating the possible impact of dust on hurricanes is comparing high resolution simulations (~0.5°x0.5°, 31 vertical levels) with and without radiatively active dust aerosols. To accomplish this task, we are using the general circulation model ECHAM6 coupled to a modified version of the aerosol model HAM, ECHAM6-HAM-Dust. Instead of the five aerosol species HAM normally contains, the modified version takes only insoluble dust into account, but modifies the scavenging parameters in order to have a similar lifetime of dust as in the full ECHAM6-HAM. All remaining aerosols are prescribed. To evaluate the effects of dust on hurricanes, a TC detection and tracking method is applied on the results. ECHAM6-HAM-Dust was used in two configurations, one with radiatively active dust aerosols and one with dust being not radiatively active. For both set-ups, 10 Monte-Carlo simulations of the year 2005 were performed. A statistical method which identifies controlling parameters of hurricane genesis was applied on North Atlantic developing and non-developing disturbances in all simulations, comparing storms in the two sets of simulations. Hereby, dust can be assigned a more influencing role on TC genesis in the simulations with active dust. Despite dust is seeming to have a negative influence on TC genesis, the relative importance of dust compared to the sea surface temperature (SST) cannot be determined thoroughly. This is largely due to a similar pattern of SST and dust off the west coast of Africa, so that possible effects of dust and SST could hardly be separated.

  7. Endotoxin concentration in poultry houses for laying hens kept in cages or in alternative housing systems.

    PubMed

    Huneau-Salaün, A; Le Bouquin, S; Bex-Capelle, V; Huonnic, D; Balaine, L; Guillam, M-T; Squizani, F; Segala, C; Michel, V

    2011-10-01

    Endotoxins as components of organic dust may have adverse effects on the respiratory health of workers in poultry buildings. The move towards more welfare-friendly housing systems for layers may increase worker exposure to air contaminants due to the use of litter. The endotoxin concentrations in the inhalable fraction of airborne dust (below 100?µm) from cage and alternative system houses (on-floor, free range and aviaries) were compared under both experimental and commercial conditions. The endotoxin concentration was higher in experimental aviaries (median: 565?EU/mł, range: 362-1491?EU/mł) than in cage housing (98?EU/mł (51-470)). In field conditions, the endotoxin concentration in the air of 13 alternative houses was higher (35 to 3156?EU/mł) than in cage system buildings (n?=?8, 78-576?EU/mł). It was correlated to the respirable dust concentration (fraction below 5?µm) and to the temperature inside the hen house but no seasonal variation was observed. The present study emphasises that considerable worker exposure to endotoxins may occur in laying houses, especially in alternative systems. PMID:22029777

  8. Metal Dusting of Heat-Resistant Alloys

    E-print Network

    Al-Meshari, Abdulaziz I

    Metal dusting leads to disintegration of such alloys as iron and nickel-based into a “dust” of particulate metal, metal carbide, carbon, and/or oxide. It occurs in strongly carburising environments at 400-900°C. Literature survey has shown...

  9. Appendix C.1 THE LEAD LABORATORY

    E-print Network

    for quality control. The reportable concentration range for lead in paint or in dust, and the preparation-based paint (>0.5% by weight) and in lead contaminated dust (>1 mg/g) present the potential for contaminatingAppendix C.1 THE LEAD LABORATORY By PATRICK J. PARSONS, Ph.D.1 J. JULIAN CHISOLM, JR., M.D.2

  10. Acceleration of dust particles by vortex ring

    E-print Network

    Ehsan, Zahida; Vranjes, J; Coppins, M; Khan, R; Poedts, S; Allen, J E

    2009-01-01

    It is shown that nonlinear interaction between large amplitude circularly polarized EM wave and dusty plasma leads to a nonstationary ponderomotive force which in turn produces a vortex ring, and magnetic field. Then the ensuing vortex ring in the direction of propagation of the pump wave can accelerate the micron-size dust particles which are initially at rest and eventually form a non relativistic dust jet. This effect is purely nonstationary and unlike linear vortices, dust particles do not rotate here. Specifically, it is pointed out that the vortex ring or closed filament can become potential candidate for the acceleration of dust in tokamak plasmas.

  11. Conformal House

    E-print Network

    Thomas A Ryttov; Francesco Sannino

    2009-06-01

    We investigate the gauge dynamics of nonsupersymmetric SU(N) gauge theories featuring the simultaneous presence of fermionic matter transforming according to two distinct representations of the underlying gauge group. We bound the regions of flavors and colors which can yield a physical infrared fixed point. As a consistency check we recover the previously investigated conformal windows bounds when restricting to a single matter representation. The earlier conformal windows can be imagined to be part now of the new conformal house. We predict the nonperturbative anomalous dimensions at the infrared fixed points. We further investigate the effects of adding mass terms to the condensates on the conformal house chiral dynamics and construct the simplest instanton induced effective Lagrangian terms.

  12. Smart Houses

    NASA Technical Reports Server (NTRS)

    1987-01-01

    GWS takes plans for a new home and subjects them to intensive computerized analysis that does 10,000 calculations relative to expected heat loss and heat gain, then provides specifications designed specifically for each structure as to heating, cooling, ventilation and insulation. As construction progresses, GWS inspects the work of the electrical, plumbing and insulation contractors and installs its own Smart House Radiant Barrier. On completion of the home, GWS technicians use a machine that creates a vacuum in the house and enables computer calculation of the air exchanged, a measure of energy efficiency. Key factor is the radiant barrier, borrowed from the Apollo program. This is an adaptation of a highly effective aluminized heat shield as a radiation barrier holding in or keeping out heat, cold air and water vapor.

  13. Lead Poisoning in Children.

    ERIC Educational Resources Information Center

    Lin-Fu, Jane S.

    This publication is a guide to help social and health workers plan a preventive campaign against lead poisoning, a cause of mental retardation other neurological handicaps, and death among children. The main victims are 1- to 6-year-olds living in areas where deteriorating housing prevails. Among the causes of lead poisoning are: ingestion of…

  14. Freedom House

    NSDL National Science Digital Library

    Founded in 1941, Freedom House was organized by prominent Americans who were concerned with mounting threats to peace and democracy. Today, as in previous decades, their mission includes promoting "the growth of freedom by encouraging U.S. policymakers, international institutions, and the governments of established democracies to adopt policies that advance human rights and democracy around the world." First-time visitors may wish to begin by looking to the right-hand side of the homepage to the "Around the World" section. Here visitors can learn about the work that the Freedom House organization is doing in other parts of the world, and more importantly, they can read their in-house reports on democratic movements in different countries. Moving along, the left-hand side of the page includes links to their other publications, which include the "Nations In Transit" series. This particular series takes a long view on political reform in the former Communist states of Europe and Eurasia. To really get a full appreciation of the site's contents and scope requires several visits, but it should have no problem holding the attention of public policy types and scholars.

  15. Metal dusting of nickel-containing alloys

    SciTech Connect

    Baker, B.A.; Smith, G.D. [Inco Alloys International, Inc., Huntington, WV (United States)

    1998-12-31

    Metal dusting is a catastrophic form of carburization which leads to pitting and grooves as the affected metal disintegrates into a mixture of powdery carbon, metallic particles, and possibly oxides and carbides. This high temperature carburization mode is not yet well understood and while relatively infrequent, can be economically disastrous when it does occur in large and complex chemical and petrochemical process streams. References in the literature show that all classes of heat resistant alloys are prone to metal dusting, given the necessary and specific environmental conditions. These same references describe the environments that plague nickel-containing alloys and are used as the basis for postulation on the probable corrosion mechanisms responsible for metal dusting. Using alloy 800 and other nickel-containing alloys and metal dusting atmospheres, an effort is made to examine the steps in the metal dusting process and the temperature ranges over which metal dusting occurs.

  16. Dust agglomeration

    NASA Technical Reports Server (NTRS)

    2000-01-01

    John Marshall, an investigator at Ames Research Center and a principal investigator in the microgravity fluid physics program, is studying the adhesion and cohesion of particles in order to shed light on how granular systems behave. These systems include everything from giant dust clouds that form planets to tiny compressed pellets, such as the ones you swallow as tablets. This knowledge should help us control the grains, dust, and powders that we encounter or use on a daily basis. Marshall investigated electrostatic charge in microgravity on the first and second U.S. Microgravity Laboratory shuttle missions to see how grains aggregate, or stick together. With gravity's effects eliminated on orbit, Marshall found that the grains of sand that behaved ever so freely on Earth now behaved like flour. They would just glom together in clumps and were quite difficult to disperse. That led to an understanding of the prevalence of the electrostatic forces. The granules wanted to aggregate as little chains, like little hairs, and stack end to end. Some of the chains had 20 or 30 grains. This phenomenon indicated that another force, what Marshall believes to be an electrostatic dipole, was at work.(The diagram on the right emphasizes the aggregating particles in the photo on the left, taken during the USML-2 mission in 1995.)

  17. In-situ dust measurements by a lunar lander

    NASA Astrophysics Data System (ADS)

    Srama, Ralf; Sternovsky, Zoltan; Horanyi, Mihaly; Gruen, Eberhard; Krueger, Harald; Laufer, Rene; Roeser, Hans-Peter; Postberg, Frank; Kempf, Sascha; Moragas-Klostermeyer, Georg; Mocker, Anna; Fiege, Katherina; Li, Yanwei

    2012-07-01

    Charged dust grains on the lunar surface impact our future exploration of the moon. Serious problems for exploration activities were revealed by the Apollo missions. Dust shows strong adhesion to equipment and clothes and makes breathing difficult within a spacecraft. The micron- and submicron sized grains are embedded in the lunar plasma environment and their physical properties determine their dynamics. The solar wind, UV light and shadows lead to temporal effects in plasma densities and dust grain charging states. The dust populations relevant for the processes on the surface are: interplanetary and interstellar dust, levitated dust and, especially, dust ejecta generated by primary impacts on the surface. A dust instrument on the surface shall distinguish the three populations and characterize their charging state, size, speed and directionality distribution. Dust measurements shall be performed in conjunction with surface plasma and surface electric field characterizations.

  18. Analytical evaluation of the Tsytovich-Angelis dust-dust collision functions arising from the kinetic theory of dusty plasmas

    SciTech Connect

    Mamedov, B. A. [Department of Physics, Faculty of Arts and Sciences, Gaziosmanpasa University, Tokat 60100 (Turkey)

    2010-11-15

    An efficient analytical calculation approach is presented for the Tsytovich-Angelis dust-dust collision functions consisting of the kinetic theory of dusty plasmas. This method is based on the use of binomial expansion theorem for the analytical representation of the dust-dust collision functions. The analytical calculation offers the advantage that leads to a mathematical expression, which allows the direct calculation of the dust-dust collision functions. The proposed algorithm is implemented numerically using a computer program, and its convergence properties are investigated.

  19. Dust Measurements in Tokamaks

    SciTech Connect

    Rudakov, D; Yu, J; Boedo, J; Hollmann, E; Krasheninnikov, S; Moyer, R; Muller, S; Yu, A; Rosenberg, M; Smirnov, R; West, W; Boivin, R; Bray, B; Brooks, N; Hyatt, A; Wong, C; Fenstermacher, M; Groth, M; Lasnier, C; McLean, A; Stangeby, P; Ratynskaia, S; Roquemore, A; Skinner, C; Solomon, W M

    2008-04-23

    Dust production and accumulation impose safety and operational concerns for ITER. Diagnostics to monitor dust levels in the plasma as well as in-vessel dust inventory are currently being tested in a few tokamaks. Dust accumulation in ITER is likely to occur in hidden areas, e.g. between tiles and under divertor baffles. A novel electrostatic dust detector for monitoring dust in these regions has been developed and tested at PPPL. In DIII-D tokamak dust diagnostics include Mie scattering from Nd:YAG lasers, visible imaging, and spectroscopy. Laser scattering resolves size of particles between 0.16-1.6 {micro}m in diameter; the total dust content in the edge plasmas and trends in the dust production rates within this size range have been established. Individual dust particles are observed by visible imaging using fast-framing cameras, detecting dust particles of a few microns in diameter and larger. Dust velocities and trajectories can be determined in 2D with a single camera or 3D using multiple cameras, but determination of particle size is problematic. In order to calibrate diagnostics and benchmark dust dynamics modeling, pre-characterized carbon dust has been injected into the lower divertor of DIII-D. Injected dust is seen by cameras, and spectroscopic diagnostics observe an increase of carbon atomic, C2 dimer, and thermal continuum emissions from the injected dust. The latter observation can be used in the design of novel dust survey diagnostics.

  20. 1. EXTERIOR VIEW OF NEW FAN HOUSE AND HILLMAN FAN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. EXTERIOR VIEW OF NEW FAN HOUSE AND HILLMAN FAN HOUSE LOOKING NORTHWEST The building on the left, the New Fan House, houses a Corliss steam engine which powered a Buffalo Forge Company single inlet Duplex Conoidal centrifugal exhausted fan through a metal updraft chimney. Part of the brick airway leading to the Baltimore shaft is visible to its right rear. The Hillman Fan House, on the right, houses the 1883 double inlet Guibal fan. The south entry, the curve of the fan housing, and brick updraft chimney are visible in this view. - Dorrance Colliery Fan Complex, South side of Susquehanna River at Route 115 & Riechard Street, Wilkes-Barre, Luzerne County, PA

  1. Martian Dust Simulator

    NASA Technical Reports Server (NTRS)

    Zuray, Monica; Houston, Karrie; Lorentson, Chris

    2008-01-01

    The Martian Dust Simulator (MDS) was designed to investigate the contamination effects of Martian soil and rock on the performance and function of flight-like microvalves and flight-like filters located within the Sample Analysis at Mars (SAM) instrument suite. The SAM instrument suite, which houses over fifty percent of the science payload, is located on-board the Mars exploration rover. The mission objective of the Mars Science Laboratory Rover is to determine the past, present, and future habitability of Mars. It will serve as a robot geologist, traveling the Mars surface for a period of one Martian year (equivalent to two earth years). The microvalves were designed as a conduit to control the flow of Martian gas to the science instruments. If exposed to particle sizes greater than half a micron, both the science instruments and science equipment, including forty-seven microvalves, could experience performance degradation. As a result, filters were used at various gas inlets to protect flight hardware from particulate degradation. Additionally, the filters serve as the only interface between the Martian environment and the mechanisms within SAM. The MDS operates at 7 Torr (0.135 psi) with a gas flow rate of 0 to 20 m/s. Iron (III) Oxide was the only dust particle specimen used, although several others were initially considered (i.e. JSC-Mars-1, Corundum Powder (Al2O3), Hydrated Sulfate, and Belville (Basalt)). The overarching goal of the MDS is to demonstrate that the Mars exploration program is adequately designed and prepared for the Martian mission environment.

  2. Validation of a 20-year forecast of US childhood lead poisoning: Updated prospects for 2010

    Microsoft Academic Search

    David E.. Jacobs; Rick Nevin

    2006-01-01

    We forecast childhood lead poisoning and residential lead paint hazard prevalence for 1990–2010, based on a previously unvalidated model that combines national blood lead data with three different housing data sets. The housing data sets, which describe trends in housing demolition, rehabilitation, window replacement, and lead paint, are the American Housing Survey, the Residential Energy Consumption Survey, and the National

  3. Assessing the human health risk for aluminium, zinc and lead in outdoor dusts collected in recreational sites used by children at an industrial area in the western part of the Bassin Minier de Provence, France

    NASA Astrophysics Data System (ADS)

    Reis, A. P.; Patinha, C.; Noack, Y.; Robert, S.; Dias, A. C.; Ferreira da Silva, E.

    2014-11-01

    The Western part of the “Bassin Minier de Provence”, a former coal mining area, is still occupied by old polluting industries such as a coal-fired power plant and an alumina factory. In 2011 a preliminary outdoor dust survey was carried out in the area as the first step to an exposure and health risk assessment study. Dust samples were taken at 19 sites distributed across the study area, depending on the location of recreational areas used by children to play outdoors. Pseudo-total concentrations of Al, Zn and Pb were determined by ICP-MS and bioaccessible concentrations were estimated using the Unified BARGE Method. Exposure was calculated according to a scenario evaluation approach for dust ingestion and dermal contact routes. Estimation of health risk for exposure to Al, Zn and Pb in outdoor dust was based on the summation of individual risks for the oral and dermal routes. Results show that Al occurs in very high concentrations but mainly innon-bioaccessible forms, especially near the alumina plant. Zinc and Pb occur in low-average levels but mainly in bioaccessible forms. The estimated potential risk decreases according to Pb ? Al > Zn and is lower for the ingestion route. The preliminary results presented in this study indicate that, for Al and Zn, the outdoor dusts of the BMP represent an acceptable risk to children's health. However, the estimated hazard quotients suggest that there is some health risk associated to environmental Pb.

  4. Concentrations of lead and mercury in multimedia samples from homes near the former Clark Air Base, Philippines.

    PubMed

    Riederer, Anne M; Shine, James P; Danan, Lieza M; Ford, Timothy E

    2005-04-01

    We measured lead and mercury in samples collected from 31 homes in communities near the former Clark Air Base, Philippines during May and October 2002. Sample media included water used for drinking and cooking, house dust and entryway soil. Composite samples of 15 food items purchased at local markets were also collected. Samples were analyzed for total lead (Pb) and total mercury (Hg) to evaluate the relative importance of each media to residential exposure concentrations in the community adjacent to Clark (Community A) versus a control community 5 km away (Community B). In general, we measured low (e.g. background) to undetectable levels of the target analytes in all media sampled with two important exceptions. First, the Hg concentrations we measured in canned mackerel composites, which were within the range reported for mackerel from other locations worldwide, may pose a risk to pregnant women who are frequent consumers (e.g. one or more cans per day). Second, we measured Pb above the USEPA residential screening concentration (400 mug/g) in dust and soil from two homes, illustrating the need for periodic residential lead monitoring in these and other communities in the Philippines. We found no significant difference between Communities A and B with respect to Pb and Hg concentrations in water or food, although we were not able to detect very low levels of Pb in most of the foods we sampled because of trace Pb contamination added during sample homogenization. Although the Pb levels we measured in dust and soil from Community A homes were higher on average than Community B homes, the levels in both communities were low (e.g. background) thus we did not investigate the difference further. To our knowledge, these are the first reported measurements of Pb in house dust in the Philippines. The concentrations of Pb we measured in house dust were significantly higher than those in entryway soil from both communities, adding empirical support to the assertion that yard soil should not be considered a proxy for house dust in exposure studies in the Philippines or elsewhere. PMID:15833241

  5. Inactivation of dust mites, dust mite allergen, and mold from carpet.

    PubMed

    Ong, Kee-Hean; Lewis, Roger D; Dixit, Anupma; MacDonald, Maureen; Yang, Mingan; Qian, Zhengmin

    2014-01-01

    Carpet is known to be a reservoir for biological contaminants, such as dust mites, dust mite allergen, and mold, if it is not kept clean. The accumulation of these contaminants in carpet might trigger allergies or asthma symptoms in both children and adults. The purpose of this study is to compare methods for removal of dust mites, dust mite allergens, and mold from carpet. Carpets were artificially worn to simulate 1 to 2 years of wear in a four-person household. The worn carpets were inoculated together with a common indoor mold (Cladosporium species) and house dust mites and incubated for 6 weeks to allow time for dust mite growth on the carpet. The carpets were randomly assigned to one of the four treatment groups. Available treatment regimens for controlling carpet contaminants were evaluated through a literature review and experimentation. Four moderately low-hazard, nondestructive methods were selected as treatments: vacuuming, steam-vapor, Neem oil (a natural tree extract), and benzalkonium chloride (a quaternary ammonium compound). Steam vapor treatment demonstrated the greatest dust mite population reduction (p < 0.05) when compared to other methods. The two physical methods, steam vapor and vacuuming, have no statistically significant efficacy in inactivating dust mite allergens (p = 0.084), but have higher efficacy when compared to the chemical method on dust mite allergens (p = 0.002). There is no statistically significant difference in the efficacy for reducing mold in carpet (p > 0.05) for both physical and chemical methods. The steam-vapor treatment effectively killed dust mites and denatured dust mite allergen in the laboratory environment. PMID:24467247

  6. Dust feed mechanism

    DOEpatents

    Milliman, Edward M. (Benton City, WA)

    1984-01-01

    The invention is a dust feed device for delivery of a uniform supply of dust for long periods of time to an aerosolizing means for production of a dust suspension. The device utilizes at least two tandem containers having spiral brushes within the containers which transport the dust from a supply to the aerosolizer means.

  7. Properties of Dust

    NSDL National Science Digital Library

    The University of Texas McDonald Observatory

    2004-01-01

    In this activity, learners carry out a scientific investigation of dust in their classroom. Learners produce an analysis on graph paper of the dust they collect over the course of a few days. Then, learners extend their experience to examining the properties of dust in space and the Spitzer Space Telescope, which astronomers use to investigate interstellar dust.

  8. Happy Birthday White House!

    ERIC Educational Resources Information Center

    Dillon, Doris; And Others

    1992-01-01

    An integrated elementary teaching package offers interesting facts about presidents and the White House. Cross-curricular activities focus on architecture, presidential birthplaces, portraits, communications, science, technology, touring the White House, children in the White House, a day in the life of the White House, and a White House birthday…

  9. Metal concentrations and distribution in the household, stairs and entryway dust of some Egyptian homes

    NASA Astrophysics Data System (ADS)

    Hassan, Salwa Kamal Mohamed

    2012-07-01

    Household, stairs and entryway dust samples were collected from 16 houses distributed across Greater Cairo by using vacuum cleaner and sweeping methods during summer season of 2009. Lead (Pb), nickel (Ni), cadmium (Cd), aluminum (Al), iron (Fe), zinc (Zn), cobalt (Co), chromium (Cr) and copper (Cu) were measured in different dust particle sizes: <38 ?m, >38-45 ?m and >45-63 ?m. The highest average concentrations of Pb, Ni, Cd, Co, Cu, and Cr in different particle sizes were found in entryway followed by household and stairs. Al, Fe and Zn concentrations followed the pattern of entryway > stairs > household. Pb, Ni, Cd, Zn, Co and Cr were found in significantly (p < 0.01) higher concentrations in dust of the small particle size (<38 ?m), whereas Al, Fe and Cu were detected in significantly (p < 0.01) higher concentrations in dust of the large particle size (>45-63 ?m). The average concentrations of the individual metals in dust of the small particle size (<38 ?m) were 268, 196.4 and 254.49 ?g gm-1 for Pb, 49.6, 43.5 and 46.66 ?g gm-1 for Ni, 2.86, 2.15 and 2.71 ?g gm-1 for Cd, 4340, 3796 and 2602 ?g gm-1 for Al, 2860, 2200 and 2004 ?g gm-1 for Fe, 209.25, 152.3 and 103.26 ?g gm-1 for Zn, 4.1, 2.88 and 1.96 ?g gm-1 for Co, 85.99, 74.06 and 83.17 ?g gm-1 for Cr and 168.2, 156.5 and 122.02 ?g gm-1 for Cu in entryway, stairs and household, respectively. The mean concentrations of Cu and Pb in the entryway, stairs and household dust exceeded the maximum permissible limit 100 ?g gm-1 for Cu and Pb in soil. The highest concentrations of Pb, Cd, Co and Ni were found in urban areas, Al and Fe in the residential areas, and Cu, Zn and Cr in the residential near to industrial area. Significant positive correlation (p < 0.001) were found between the metal concentrations in household and entryway dust, indicating that the metals in household dust may be derived from outdoor sources in addition to dust generated within the house itself. The contribution of anthropogenic sources, especially traffic emission, to metal levels in household, entryway and stairs dust was reflected by the high values of enrichment factors for Pb, Cd, Zn and Cu and Ni and Cr in fine dust particle compared to the average crustal composition. Insignificant positive correlation coefficients were found between the concentrations of Pb and other metals in household dust. However, the correlation coefficients between the concentrations of Cd, Ni, Cr, Cu, Zn and Fe were statistically significant.

  10. ENVIRONMENTAL DETERMINANTS OF LEAD BURDENS IN CHILDREN

    EPA Science Inventory

    Lead burdens in children were studied in relation to exposure to lead from soil and from automobile traffic in Charleston, SC. Preschool aged black children exposed to a variety of soil leads and traffic volumes were recruited in a house-to-house survey. Data regarding soil, traf...

  11. Dust Avalanches

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Crater wall dust avalanches in southern Arabia Terra.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

    Image information: VIS instrument. Latitude 10.3, Longitude 24.5 East (335.5 West). 19 meter/pixel resolution.

  12. Factors associated with elevated blood lead concentrations in children in Karachi, Pakistan.

    PubMed Central

    Rahbar, Mohammad Hossein; White, Franklin; Agboatwalla, Mubina; Hozhabri, Siroos; Luby, Stephen

    2002-01-01

    OBJECTIVES: To confirm whether blood lead concentrations in Karachi were as high as reported in 1989 and to identify which types of exposure to lead contribute most to elevated blood lead concentrations in children in Karachi. METHODS: A total of 430 children aged 36-60 months were selected through a geographically stratified design from the city centre, two suburbs, a rural community and an island situated within the harbour at Karachi. Blood samples were collected from children and a pretested questionnaire was administered to assess the effect of various types of exposure. Cooked food, drinking-water and house dust samples were collected from households. FINDINGS: About 80% of children had blood lead concentrations 10 g/dl, with an overall mean of 15.6 g/dl. At the 5% level of significance, houses nearer to the main intersection in the city centre, application of surma to children's eyes, father's exposure to lead at workplace, parents' illiteracy and child's habit of hand- to-mouth activity were among variables associated with elevated lead concentrations in blood. CONCLUSION: These findings are of public health concern, as most children in Karachi are likely to suffer some degree of intellectual impairment as a result of environmental lead exposure. We believe that there is enough evidence of the continuing problem of lead in petrol to prompt the petroleum industry to take action. The evidence also shows the need for appropriate interventions in reducing the burden due to other factors associated with this toxic element. PMID:12471396

  13. Introduction to Indoor Air Quality: Lead (Pb)

    MedlinePLUS

    ... Tobacco Smoke Stoves, Heaters, Fireplaces, and Chimneys Volatile Organic Compounds (VOCs) Read "Care for Your Air: A ... are exposed to lead: through air, drinking water, food, contaminated soil, deteriorating paint, and dust. Airborne lead ...

  14. Renovate Right: Important Lead Hazard Information for Families, Child Care Providers and Schools

    ERIC Educational Resources Information Center

    US Environmental Protection Agency, 2008

    2008-01-01

    Lead can affect children's brains and developing nervous systems, causing reduced IQ, learning disabilities, and behavioral problems. Lead is also harmful to adults. Lead in dust is the most common way people are exposed to lead. People can also get lead in their bodies from lead in soil or paint chips. Lead dust is often invisible. Lead-based…

  15. White House

    MedlinePLUS

    ... Issues Economy Education Foreign Policy Health Care Immigration Climate Change Energy and Environment More Civil Rights Defense Disabilities ... a better immigration system. A Plan to Fight Climate Change We have a moral obligation to lead the ...

  16. Dust and Ocean Plants

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Adding iron to the diet of marine plant life has been shown in shipboard experiments to boost the amount of carbon-absorbing phytoplankton in certain parts of the world's oceans. A new study promises to give scientists their first global picture of the extent of these unique 'iron-limited' ocean regions, an important step in understanding how the ocean's biology controls the flow of carbon between the atmosphere and the ocean. The new study by researchers at NASA's Goddard Space Flight Center and the Department of Energy's Oak Ridge National Laboratory was presented at the American Geophysical Union's annual meeting in San Francisco on Friday, Dec. 15, 2000. Oceanic phytoplankton remove nearly as much carbon from the atmosphere each year as all land-based plants. Identifying the location and size of nutrient-limited areas in the open ocean has challenged oceanographers for nearly a century. The study pinpointed iron-limited regions by seeing which phytoplankton-rich areas of the world's oceans were also areas that received iron from wind-blown dust. In this map, areas with high levels of chlorophyll from phytoplankton and high levels of dust deposition (high correlation coefficients) are indicated in dark brown. Dust deposition was calculated by a 3-year modelled climatology for the years 1996-1998. The chlorophyll measurements are from 1998 observations from the SeaWiFS (Sea-viewing Wide Field-of-view Sensor) instrument on the OrbView-2 satellite. 'Global, satellite-based analyses such as this gives us insight into where iron deposition may be limiting ocean biological activity,' says lead author David Erickson of Oak Ridge National Laboratory's Computer Science and Mathematics Division. 'With this information we will be able to infer how the ocean productivity/iron deposition relationship might shift in response to climate change.' Map Source: David Erickson, Oak Ridge National Laboratory's Computer Science and Mathematics Division

  17. Dust Distribution during Reionization

    E-print Network

    Erik Elfgren; Francois-Xavier Désert; Bruno Guiderdoni

    2007-10-22

    The dust produced by the first generation of stars will be a foreground to cosmic microwave background. In order to evaluate the effect of this early dust, we calculate the power spectrum of the dust emission anisotropies and compare it with the sensitivity limit of the Planck satellite. The spatial distribution of the dust is estimated through the distribution of dark matter. At small angular scales ($\\ell \\gtrsim 1000$) the dust signal is found to be noticeable with the Planck detector for certain values of dust lifetime and production rates. The dust signal is also compared to sensitivities of other instruments. The early dust emission anisotropies are finally compared to those of local dust and they are found to be similar in magnitude at mm wavelengths.

  18. Know the Facts Lead poisoning is caused by swallowing or

    E-print Network

    and speech · Make it hard to pay attention and learn FACT Most children get lead poisoning from paint. Sometimes lead comes from things other than paint in your home, such as: · Candy, toys, glazed pottery and tap water 2. Keep children away from lead paint and dust. · Use wet paper towels to clean up lead dust

  19. Dust from AGB stars

    E-print Network

    Anja C. Andersen

    2007-02-22

    Dust is formed in the expanding atmosphere during late stages of stellar evolution. Dust influences the dynamics and thermodynamics of the stellar atmosphere by its opacity. The dust opacity depends both on the optical properties of the grain material as well as on the amount of dust present. A rich source of information on some mineral phases of dust in AGB stars comes from the study of presolar grains from meteorites. This paper presents a short overview of presolar grains studies and describes how the optical properties of dust grains are obtained in the laboratory.

  20. Contextual view to northwest of Burton Park Club House and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Contextual view to northwest of Burton Park Club House and Amphitheater. Steps lead up from wings of stage area to club house grade level (135mm lens). - Burton Park, Club House & Amphitheater, Adjacent ot south end of Chestnut Avenue, San Carlos, San Mateo County, CA