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Sample records for pcb-contaminated soils risk

  1. PCB contamination in soils of the Pearl River Delta, South China: levels, sources, and potential risks.

    PubMed

    Zhang, Haibo; Luo, Yongming; Teng, Ying; Wan, Hongfu

    2013-08-01

    Polychlorinated biphenyls (PCBs) contamination in tropical and sub-tropical areas and the associated risks have attracted great concern. A total of 69 samples representing five distinct land types were collected to assess PCB concentrations in the Pearl River Delta (PRD), South China, including spatial distributions in soils of the area, the probable anthropogenic sources, and related potential risks. PCBs concentrations in soils of the PRD ranged from 0.3 to 202 ng g(-1). More severe PCBs contamination was presented in the western part than in the eastern part of the PRD region. The PCBs were dominated by low-chlorinated biphenyls; however, the proportion of higher-chlorinated biphenyls was elevated with the influence of industrial activities. Principal component analysis indicated that PCBs contamination in soils of the PRD region was mainly associated with 1#PCBs, while 2#PCB and e-waste emission in South China also accounted for it partly, especially to the industrial activity severely impacted areas. Toxic equivalent (TEQ) of the dioxin-like PCBs in the soils indicated that higher risk of PCB contamination was presented in the Dongjiang River Valley (55 ng TEQ kg(-1), on average) than in the Xijiang River Valley, and were mostly contributed by the congener of PCB126. PMID:23354616

  2. Remediation of PCB contaminated soils using iron nano-particles.

    PubMed

    Varanasi, Patanjali; Fullana, Andres; Sidhu, Sukh

    2007-01-01

    In this study, iron nano-particles were used to remediate PCB contaminated soil and an attempt was made to maximize PCB destruction in each treatment step. The results show that nano-particles do aid in the dechlorination process and high PCB destruction efficiencies can be achieved. The destruction efficiency during the preliminary treatment (mixing of soil and iron nano-particles in water) can be increased by increasing the water temperature. The maximum thermal destruction (pyrolysis/combustion of soil after preliminary treatment) of soil-bound PCBs occurs at 300 degrees C in air. A minimum total PCB destruction efficiency of 95% can be achieved by this process. The effect of changing treatment parameters such as type of mixing, time of mixing and mixing conditions and application of other catalysts like iron oxide and V(2)O(5)/TiO(2) was also investigated. It was found that at 300 degrees C in air, iron oxide and V(2)O(5)/TiO(2) are also good catalysts for remediating PCB contaminated soils. PMID:16962632

  3. PCB contamination from polysulphide sealants in residential areas-exposure and risk assessment.

    PubMed

    Priha, Eero; Hellman, Sannamari; Sorvari, Jaana

    2005-04-01

    From the late 1950s to the early 1970s elastic polysulphide sealants were used in outdoor seams between concrete blocks in prefabricated buildings. The sealants contained 5-30% polychlorinated biphenyls (PCBs). Due to the weathering of sealants in general and the replacement of seams with new PCB-free materials in the 1990s, PCBs have drifted to the soil adjacent to buildings. The objectives of this study were to survey PCB contamination in the surroundings of former PCB-containing buildings and to evaluate the risks to human health. Samples from soil, and also from blood serum of residents, were collected to obtain data for exposure assessment. The health risk assessment was based on deterministic and probabilistic calculations for cancer and non-cancer risks. Soil ingestion and dermal contact were considered the main routes of exposure and children the most important exposed group. The mean total PCB concentration was 6.83 mg/kg within 2m of the buildings and 0.52 mg/kg within 3-10 m from of the buildings. The deterministic risk assessment with conservative parameters resulted in lifetime cancer risk estimates on the order of 10(-6)-10(-7). The lifetime average daily dose (LADD) for PCBs was less than 10% of the reference dose (RfD) 0.02 microg/kg day, which is based on immunosupression in monkeys. The LADD corresponding to the total site attributable exposure was less than 10% of the estimated average dietary PCB intake in Finland. Children can, however, in worst cases be exposed to daily doses near the level of the RfD. Low cost measures are recommended to reduce possible exposure of children. PMID:15788176

  4. Technical note monitoring native vegetation on a dumpsite of PCB-contaminated soil.

    PubMed

    Pavlíková, Daniela; Macek, Tomas; Macková, Martina; Pavlík, Milan

    2007-01-01

    Composition of native vegetation on a polychlorinated biphenyls (PCB)-contaminated soil dumpsite at Lhenice, South Bohemia (Czech Republic), was determined and species variability in the accumulation of PCBs in plant biomass was investigated. Soil stripping contaminated by PCBs originated at a factory producing electrical transformers that mostly used the commercial PCB mixture Delor 103 and 106. The PCB content of soil in the most contaminated part of the dumpsite reached 153 mg kg(-1) dry soil. Low diversity of plant species was found on the dumpsite. Results showed three grass species, Festuca arundinacea Schreb., Phalaroides arundinacea (L.) Rauschert., and Calamagrostis epigeios (L.) Roth., to be the major components of the vegetation and confirmed their high tolerance toward PCB contamination. The highest content of PCB in plant biomass--813.2 microg kg(-1) dry biomass--was determined in Festuca aboveground biomass. For phytoextraction purposes especially, Festuca can be recommended due to its high biomass yield, but its bioconcentration factor was very low (0.006). Tripleurospermum maritimum (L.) Sch. Bip. and Cirsium arvense (L.) Scop. grew mainly at the margins of the most contaminated part of the dumpsite. The PCB content determined in their aboveground biomass-278.7 and 289.5 microg kg(-1) dry biomass, respectively--was nonsignificantly lower compared to grass species Phalaroides and Calamagrostis. Salix (Salix viminalis L. and Salix caprea L.) was monitored among plant species composition at this site as a representative of woody species. PMID:18246716

  5. Electroremediation of PCB contaminated soil combined with iron nanoparticles: Effect of the soil type.

    PubMed

    Gomes, Helena I; Dias-Ferreira, Celia; Ottosen, Lisbeth M; Ribeiro, Alexandra B

    2015-07-01

    Polychlorinated biphenyls (PCB) are carcinogenic and persistent organic pollutants that accumulate in soils and sediments. Currently, there is no cost-effective and sustainable remediation technology for these contaminants. In this work, a new combination of electrodialytic remediation and zero valent iron particles in a two-compartment cell is tested and compared to a more conventional combination of electrokinetic remediation and nZVI in a three-compartment cell. In the new two-compartment cell, the soil is suspended and stirred simultaneously with the addition of zero valent iron nanoparticles. Remediation experiments are made with two different historically PCB contaminated soils, which differ in both soil composition and contamination source. Soil 1 is a mix of soils with spills of transformer oils, while Soil 2 is a superficial soil from a decommissioned school where PCB were used as windows sealants. Saponin, a natural surfactant, was also tested to increase the PCB desorption from soils and enhance dechlorination. Remediation of Soil 1 (with highest pH, carbonate content, organic matter and PCB concentrations) obtained the maximum 83% and 60% PCB removal with the two-compartment and the three-compartment cell, respectively. The highest removal with Soil 2 were 58% and 45%, in the two-compartment and the three-compartment cell, respectively, in the experiments without direct current. The pH of the soil suspension in the two-compartment treatment appears to be a determining factor for the PCB dechlorination, and this cell allowed a uniform distribution of the nanoparticles in the soil, while there was iron accumulation in the injection reservoir in the three-compartment cell. PMID:25841071

  6. Consumption of PCB-contaminated sport fish and risk of spontaneous fetal death

    SciTech Connect

    Mendola, P.; Buck, G.M.; Vena, J.E.; Zielezny, M.; Sever, L.E.

    1995-05-01

    Spontaneous fetal death has been observed among various mammalian species after exposure to polychlorinated biphenyls (PCBs). Our exposure-based cohort study assessed the relationship between consumption of PCB-contaminated Lake Ontario sport fish and spontaneous fetal death using 1820 multigravid fertile women from the 1990-1991 New York State Angler Cohort Study. Fish consumption data were obtained from food frequency questionnaires and history of spontaneous fetal death from live birth certificates. Analyses were stratified by number of prior pregnancies and controlled for smoking and maternal age. No significant increases in risk for fetal death were observed across four measures of exposure: a lifetime estimate of PCB exposure based on species-specific PCB levels; the number of years of fish consumption; kilograms of sport fish consumed in 1990-1991; and a lifetime estimate of kilograms eaten. A slight risk reduction was seen for women with two prior pregnancies at the highest level of PCB exposure (odds ratio = 0.36; 95% CI, 0.14-0.92) and for women with three or more prior pregnancies with increasing years of fish consumption (odds ratio = 0.97; 95% CI, 0.94-0.99). These findings suggest that consumption of PCB-contaminated sport fish does not increase the risk of spontaneous fetal death. 50 refs., 2 tabs.

  7. Burial, incineration solve Alaskan PCB contamination

    SciTech Connect

    Ives, J.A. ); Young, D.T. )

    1989-10-01

    Polychlorinated biphenyl (PCB) remediation at Alaska's Swanson River has excavated more than 80,000 tons of PCB-contaminated soil and isolated it in bermed and lined stock-piles. In addition, incineration of other PCB-contaminated materials has been carried out safely. This article on the site reviews its history and part of its remediation approaches.

  8. In situ application of activated carbon and biochar to PCB-contaminated soil and the effects of mixing regime.

    PubMed

    Denyes, Mackenzie J; Rutter, Allison; Zeeb, Barbara A

    2013-11-01

    The in situ use of carbon amendments such as activated carbon (AC) and biochar to minimize the bioavailability of organic contaminants is gaining in popularity. In the first in situ experiment conducted at a Canadian PCB-contaminated Brownfield site, GAC and two types of biochar were statistically equal at reducing PCB uptake into plants. PCB concentrations in Cucurbita pepo root tissue were reduced by 74%, 72% and 64%, with the addition of 2.8% GAC, Burt's biochar and BlueLeaf biochar, respectively. A complementary greenhouse study which included a bioaccumulation study of Eisenia fetida (earthworm), found mechanically mixing carbon amendments with PCB-contaminated soil (i.e. 24 h at 30 rpm) resulted in shoot, root and worm PCB concentrations 66%, 59% and 39% lower than in the manually mixed treatments (i.e. with a spade and bucket). Therefore, studies which mechanically mix carbon amendments with contaminated soil may over-estimate the short-term potential to reduce PCB bioavailability. PMID:23933124

  9. Chemical and microbiological characterization of an aged PCB-contaminated soil.

    PubMed

    Stella, T; Covino, S; Burianová, E; Filipová, A; Křesinová, Z; Voříšková, J; Větrovský, T; Baldrian, P; Cajthaml, T

    2015-11-15

    This study was aimed at complex characterization of three soil samples (bulk soil, topsoil and rhizosphere soil) from a site historically contaminated with polychlorinated biphenyls (PCB). The bulk soil was the most highly contaminated, with a PCB concentration of 705.95 mg kg(-1), while the rhizosphere soil was the least contaminated (169.36 mg kg(-1)). PCB degradation intermediates, namely chlorobenzoic acids (CBAs), were detected in all the soil samples, suggesting the occurrence of microbial transformation processes over time. The higher content of organic carbon in the topsoil and rhizosphere soil than in the bulk soil could be linked to the reduced bioaccessibility (bioavailability) of these chlorinated pollutants. However, different proportions of the PCB congener contents and different bioaccessibility of the PCB homologues indicate microbial biotransformation of the compounds. The higher content of organic carbon probably also promoted the growth of microorganisms, as revealed by phospholipid fatty acid (PFLA) quantification. Tag-encoded pyrosequencing analysis showed that the bacterial community structure was significantly similar among the three soils and was predominated by Proteobacteria (44-48%) in all cases. Moreover, analysis at lower taxonomic levels pointed to the presence of genera (Sphingomonas, Bulkholderia, Arthrobacter, Bacillus) including members with reported PCB removal abilities. The fungal community was mostly represented by Basidiomycota and Ascomycota, which accounted for >80% of all the sequences detected in the three soils. Fungal taxa with biodegradation potential (Paxillus, Cryptococcus, Phoma, Mortierella) were also found. These results highlight the potential of the indigenous consortia present at the site as a starting point for PCB bioremediation processes. PMID:26156136

  10. Surfactant-enhanced bioremediation of PAH- and PCB-contaminated soils

    SciTech Connect

    Ghosh, M.M.; Yeom, I.T.; Shi, Z.; Cox, C.D.; Robinson, K.G.

    1995-12-31

    The role of surfactants in the desorption of soil-bound polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) was investigated. The solubilization of individual PAHs in an extract of a weathered, coal tar-contaminated soil containing a mixture of PAHs and other petroleum derivatives was found to be significantly less than that for pure compounds. Batch soil washing with Triton X-100 (a commercial, nonionic alkyl phenol ethoxylate) was found to increase the effective diffusion rate of PAHs from the contaminated soil by four orders of magnitude compared to that obtained by gas purging when the results were analyzed using a radial diffusion model. At concentrations of up to 24 times its critical micelle concentration (CMC), Triton X-100 did not seem to enhance hydrocarbon degradation in the coal tar-contaminated soil; however, the biosurfactant rhamnolipid R1, at a concentration of 50x CMC, increased the rate of mineralization of 4,4{prime}-chlorinated biphenyl mobilized from a laboratory-contaminated soil by more than 60 times.

  11. DESTRUCTION OF PCB-CONTAMINATED SOILS WITH A HIGH-TEMPERATURE FLUID-WALL (HTFW) REACTOR

    EPA Science Inventory

    The objective of this project is to demonstrate the feasibility of a high temperature fluid-wall (HTFW) Reactor to detoxify biorefractory hazardous substances, as well as soils contaminated with hazardous materials, such as PCBs, dioxins, and organophosphates. A typical HTFW Reac...

  12. IN-SITU STABILIZATION/SOLIDIFICATION OF PCB-CONTAMINATED SOIL

    EPA Science Inventory

    An evaluation was performed of the International Waste Technologies (IWT) HWT-20 additive and the Geo-Con, Inc. deep-soil-mixing equipment for an in situ stabilization/solidification process and its applicability as an onsite treatment method for waste site cleanup. emonstration ...

  13. TREATABILITY STUDY REPORT OF GREEN MOUNTAIN LABORATORIES, INC.'S BIOREMEDIATION PROCESS, TREATMENT OF PCB CONTAMINATED SOILS, AT BEEDE WASTE OIL/CASH ENERGY SUPERFUND SITE, PLAISTOW, NEW HAMPSHIRE

    EPA Science Inventory

    In 1998, Green Mountain Laboratories, Inc. (GML) and the USEPA agreed to carry out a Superfund Innovative Technology Evaluation (SITE) project to evaluate the effectiveness of GML's Bioremediation Process for the treatment of PCB contaminated soils at the Beede Waste Oil/Cash Ene...

  14. Thermal dechlorination of heavily PCB-contaminated soils from a sealed site of PCB-containing electrical equipment.

    PubMed

    Gao, Xingbao; Ji, Bingjing; Huang, Qifei

    2016-08-01

    A large amount of soils are contaminated by leakage of polychlorinated biphenyls (PCBs) from sealed-up PCB-containing electrical equipment in China. Thermal dechlorination of soils contaminated with PCBs at a level of 108 mg g(-1) and PCB77 (3,3',4,4'-tetrachlorobiphenyl) as a model isomer in conjunction with calcium oxide was investigated in this study. The PCB dechlorination rate improved with increased temperature and time. The highest dechlorination rate was 85.3 %, and temperature was the main influencing factor. Pentachlorobiphenyl and tetrachlorobiphenyl in soils decreased or disappeared in response to treatment at 350 and 400 °C for 4 h, while monochlorinated biphenyl and biphenyl were detected after the reaction, indicating the presence of a dechlorination/hydrogenation pathway. Discrepancy in chlorine balance was observed after low-temperature thermal dechlorination. The species of dechlorination products were identified as amorphous carbon containing a crystalline graphite plane structure and a carbonyl group-containing polymerized product, demonstrating the existence of a dechlorination/polymerization pathway. The yield of amorphous carbon and high-molecular-weight intermediates increased with heating time. The results showed that the discrepancy in chlorine balance was because of the generation of polymerized products and undetected intermediates. PMID:27126866

  15. PCB contaminated dust on indoor surfaces--health risks and acceptable surface concentrations in residential and occupational settings.

    PubMed

    Kuusisto, Sari; Lindroos, Outi; Rantio, Tiina; Priha, Eero; Tuhkanen, Tuula

    2007-04-01

    Polychlorinated biphenyls (PCBs) have been used in diverse purposes such as indoor paints. Removal of these paints with dust creating techniques, like sandblasting, will result in contamination of building surfaces with PCB-containing dust. Objectives of this study was to analyze the PCB concentrations on surfaces after sandblasting with silica using wipe samples and estimate the resulting health risks and further calculate the risk based acceptable PCB surface concentrations that do not cause incremental lifetime cancer risk higher that 10(-5) or does not cause immunosupression effects in residential use or in occupational settings. Both deterministic and probabilistic approaches were used. The total PCB concentrations on surfaces ranged from 10 to 1100 microg/m(2). Estimated cancer risk was 1.2 x 10(-4) for childhood exposure, 1.3 x 10(-5) for adult residents and 1.5 x 10(-5) for occupational exposure. Probabilistic risk assessment revealed that point estimates were quite reasonable and located between 45th and 79th percentiles on probabilistic distribution of risk. The noncancer risks were calculated as hazard quotients (HQ) which ranged from 3.3 to 35 depending on the exposure scenario. Acceptable surface concentrations based on noncancer effects that are protective for 95% of exposed population were 7 microg/m(2) for residential use, 65 microg/m(2) for residential use if only adults will be exposed and 140 microg/m(2) for occupational use. Preliminary cleanup experiment revealed that when contaminated dust was carefully removed with industrial vacuum cleaner and further washed with terpene containing liquid the surface concentration dropped below the acceptable levels calculated in this study. PMID:17166563

  16. DETERMINATION OF RATES AND EXTENT OF DECHLORINATION IN PCB-CONTAMINATED SEDIMENTS DURING MONITORED NATURAL RECOVERY

    EPA Science Inventory

    This "Sediment Issue" summarizes investigations carried out by the National Risk Management Research Laboratory (NRMRL) of U.S. EPA to evaluate the long-term recovery of polychlorinated biphenyl (PCB)-contaminated sediments via reductive dechlorination. The magnitude, extent, an...

  17. Using SPMDs To Assess Natural Recovery Of PCB-Contaminated Sediments In Lake Hartwell, SC: I. A Field Test Of New In-Situ Deployment Methods

    EPA Science Inventory

    Results from the field testing of some innovative sampling methods developed to evaluate risk management strategies for polychlorinated biphenyl (PCB) contaminated sediments are presented. Semipermeable membrane devices (SPMDs) were combined with novel deployment methods to quan...

  18. Emerging technology report: Bench-scale testing of photolysis, chemical oxidation, and biodegradation of PCB contaminated soils, and photolysis of TCDD contaminated soils. Report for August 1991-June 1994

    SciTech Connect

    Alperin, E.; Root, D.K.

    1994-10-01

    Bench-scale tests were conducted to investigate the feasibility of a two phase detoxification process that would have application to the treatment of soils contaminated with polychlorinated biphenyls (PCBs) abd 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). The first of the process was to degrade the contaminants by using Ultraviolet (UV) radiation facilitated by the addition of a surfactant to mobilize contaminants. Biological degradation, the second step, was then used to further detoxify the soil. Results from UV testing indicated that there was no apparent destruction of the dioxin on the soil. PCB reductions ranged from less than 15% to 69%.

  19. Investigation of potential polychlorinated biphenyl (PCB) contamination on Hanford site arc-loop roads

    SciTech Connect

    Patton, G.W.; Cooper, A.T.; Riley, R.G.; Lefkovitz, L.F.; Gilfoil, T.J.

    1997-09-01

    Two roads on the Hanford Site, which had been treated during past Site operations with oil for dust suppression, were analyzed for potential polychlorinated biphenyl (PCB) contamination. The general locations of these roads are (1) off Washington State Route 240, north of Horn Rapids Dam, and (2) between the 200 East and 200 West areas, south of the 200 Area fire station. Each road had an intact crust of oil/tar on top of the underlying soil surface. A set of control samples were collected at an untreated soil site near the Prosser Barricade air sampling station. Samples were collected of the oil/tar surface crust, the soil immediately beneath the surface crust (0 - 3 cm below the crust), and a deeper soil sample (13 - 23 cm below the surface crust). Samples were collected at two locations on each road. The PCBs were extracted from the samples using a roller technique with methylene chloride, cleaned using column chromatography and high-pressure liquid chromatography, and analyzed by capillary gas chromatography using electron capture detection. The samples were analyzed for PCBs as the following technical mixtures: Aroclor 1242, Aroclor 1248, Aroclor 1254, and Aroclor 1260. All samples at all locations were less than the following detection limits: surface crust (41 ug/kg dry weight) and soil (2.1 ug/kg dry weight). These concentrations are below the U.S. Environmental Protection Agency (EPA) Region IX preliminary remediation goals for PCBs in residential soil (66 ug/kg) and well below the preliminary remediation goal for PCBs in industrial soil (340 ug/kg).

  20. USING SPMDS TO ACCESS MANAGMENT STRATEGIES FOR PCB CONTAMINATED SEDIMENTS

    EPA Science Inventory

    Dredging, in-place treatment, capping and monitored natural recovery, used together or separately are the primary approaches for managing contaminated sediment risks. Understanding how well different approaches work in different environments is critical for choosing an appropria...

  1. USING SPMDS TO ASSESS MANAGEMENT STRATEGIES FOR PCB CONTAMINATED SEDIMENTS.

    EPA Science Inventory

    Abstract: Dredging in-place treatment, capping and monitored natural recovery, used together or separately are the primary approaches for managing contaminated sediment risks. Understanding how well different approaches work in different environments is critical for choosing an...

  2. USING SPMDS TO ACCESS MANAGEMENT STRATEGIES FOR PCB CONTAMINATED SEDIMENTS

    EPA Science Inventory

    Dredging, in-place treatment, capping and monitored natural recovery, used together or separately are the primary approaches for managing contaminated sediment risks. Understanding how well different approaches work in different environments is critical for choosing an appropria...

  3. Reproductive and behavioral abnormalities in tree swallows with high levels of PCB contamination

    SciTech Connect

    McCarty, J.; Secord, A.; Tillitt, D.

    1995-12-31

    Tree Swallows (Tachycineta bicolor) breeding along the Hudson River forage extensively on PCB contaminated insects that emerge from the river. The authors studied the reproductive ecology and behavior of tree swallows breeding at several sites along the Hudson River. These sites vary in the severity of PCB contamination. PCB levels in both eggs and chicks were found to be among the highest ever reported in this species, with concentrations comparable to those found in aquatic organisms in the Hudson River. In 1994 reproductive success at PCB contaminated sites was significantly impaired, relative to other sites in New York. Reduced reproductive success was largely attributed to high levels of nest abandonment during incubation and reduced hatchability of eggs. Growth and development of nestlings was not significantly impaired. Abnormal nest building behavior was also noted in 1994, and this was studied in detail in 1995. Nests from contaminated areas are significantly smaller than those at a nearby reference site and at other sites in New York. The authors suggest that the reduced reproductive outputs at these sites are, in large part, a result of effects on the behavior of incubating females. The population-level implications of these patterns are unknown.

  4. Response of PCB contamination in stream fish to abatement actions at an industrial site

    SciTech Connect

    Southworth, G.R.; Peterson, M.J.; McCarthy, J.F.; Milne, G.

    1995-12-31

    The Paducah Gaseous Diffusion Plant (PGDP) in Paducah, Kentucky, used large quantities of PCBs in equipment associated with the great electric power requirements of isotopic enrichment of uranium. Historic losses of PCBs in the 1950s and 1960s have left a legacy of contamination at the site. A biological monitoring program implemented in 1987 found PCBs in PGDP effluents and in fish downstream from facility discharges. As a consequence, a fish consumption advisory was posted on Little Bayou Creek by the Commonwealth of Kentucky in 1987, and regulatory discharge limits for PCBs at PGDP were reduced. Monitoring at multiple locations in receiving streams indicated that PGDP discharges were more important than in stream sediment contamination as sources of PCBs to fish. Environmental management and compliance staff at PGDP led an effort to reduce PCB discharges and monitor the effects of those actions. The active discharge of uncontaminated process water to historically PCB-contaminated drainage systems was found to mobilize PCBs into KPDES (Clean Water Act) regulated effluents. Efforts to locate PCB sources within the plant, coupled with improvements in management practices and remedial actions, appear to have been successful in reducing PCB discharges from these sources. Actions included emplacing passive monitors in the plant drainage system to identify this as a chronic source, and consolidating and re-routing effluents to minimize flow through PCB-contaminated channels. As a consequence, PCB contamination in fish in small streams receiving plant discharges decreased 75% over from 1992--1995.

  5. Proof of concept for the use of macroinvertebrates as indicators of polychlorinated biphenyls (PCB) contamination in Lake Hartwell.

    PubMed

    Lazorchak, James M; Griffith, Michael B; Mills, Marc; Schubauer-Berigan, Joseph; McCormick, Frank; Brenner, Richard; Zeller, Craig

    2015-06-01

    The US Environmental Protection Agency (USEPA) develops methods and tools for evaluating risk management strategies for sediments contaminated with polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and other legacy pollutants. Monitored natural recovery is a risk management alternative that relies on existing physical, chemical, and biological processes to contain, destroy, and/or reduce the bioavailability or toxicity of in-place contaminants. These naturally occurring processes are monitored to ensure that management and recovery are progressing as expected. One approach frequently used to evaluate the recovery of contaminated sediments and associated biota is the assessment of contaminant tissue levels, or body burden concentrations, in top trophic level fish. In the present study, aquatic invertebrates were examined as an indicator of recent exposure to PCBs. The approach aimed to determine whether invertebrates collected using artificial substrates (i.e., Hester-Dendy samplers) could be used to discriminate among contaminated sites through the analyses of PCBs in whole homogenates of macroinvertebrates. Macroinvertebrates were sorted, preserved, and analyzed for total PCBs (t-PCBs), by summing 107 PCB congeners. Macroinvertebrate body burden concentrations showed similar trends to sediment t-PCB concentrations at the sites sampled. The results indicate that macroinvertebrates can be used to assess sediment contamination among sites that have different PCB contamination levels. PMID:25663426

  6. Effects of PCB contamination on the reproduction of the DAB Limanda limanda L. under laboratory conditions

    NASA Astrophysics Data System (ADS)

    Fonds, Mark; Casal, Elizabeth; Schweizer, Dominik; Boon, Jan P.; Van der Veer, Henk W.

    The effect of PCB contamination on the reproduction of female dab was studied under laboratory conditions. Females were contaminated during gonad maturation by multiple oral administration of capsules containing the technical PCB mixture Clophen A40. PCB contamination resulted in increased levels in the eggs, with concentrations of selected PCB congeners of 35 to 86 μg·g -1 lipid for PCB-exposed fish, 10 μg·g -1 lipid for eggs from fish fed with mussel meat and fish fed with shrimp. A statistically significant dose-effect relationship was found between the PCB content of the eggs and the PCB dose ingested by the fish. For eggs from the PCB-treated fish the mean fertilization rate was 61% and mean hatching 45%, compared to 67% fertilization and 59% hatching for eggs from untreated fish. Rate of development and survival of the eggs and mortality of the larvae after hatching were mainly related to incubation temperature. No statistically significant differences between untreated and PCB-treated fish could be found in egg production, egg quality, fertilization rate, hatching rate and survival of larvae.

  7. An Unrecognized Source of PCB Contamination in Schools and Other Buildings

    PubMed Central

    Herrick, Robert F.; McClean, Michael D.; Meeker, John D.; Baxter, Lisa K.; Weymouth, George A.

    2004-01-01

    An investigation of 24 buildings in the Greater Boston Area revealed that one-third (8 of 24) contained caulking materials with polychlorinated biphenyl (PCB) content exceeding 50 ppm by weight, which is the U.S. Environmental Protection Agency (U.S. EPA) specified limit above which this material is considered to be PCB bulk product waste. These buildings included schools and other public buildings. In a university building where similar levels of PCB were found in caulking material, PCB levels in indoor air ranged from 111 to 393 ng/m3; and in dust taken from the building ventilation system, < 1 ppm to 81 ppm. In this building, the U.S. EPA mandated requirements for the removal and disposal of the PCB bulk product waste as well as for confirmatory sampling to ensure that the interior and exterior of the building were decontaminated. Although U.S. EPA regulations under the Toxic Substances Control Act stipulate procedures by which PCB-contaminated materials must be handled and disposed, the regulations apparently do not require that materials such as caulking be tested to determine its PCB content. This limited investigation strongly suggests that were this testing done, many buildings would be found to contain high levels of PCBs in the building materials and potentially in the building environment. The presence of PCBs in schools is of particular concern given evidence suggesting that PCBs are developmental toxins. PMID:15238275

  8. Risk analysis of PCB exposure via the soil-food crop pathway, and alternatives for remediation at Serpukhov, Russian Federation

    SciTech Connect

    Tsongas, T.; Orlinskii, D.; Priputina, I.; Pleskachevskaya, G.; Fetishchev, A.; Hinman, G.; Butcher, W.

    2000-02-01

    A risk assessment was conducted to determine the likelihood of certain health risks resulting from exposure to soils and food crops contaminated with polychlorinated biphenyl (PCBs). PCBs have contaminated soils, river sediments, and air in the past as a result of industrial activities at a capacitor plant located in the City of Serpukhov, Russian Federation. This risk assessment and suggestions for remediation are designed to aid in decision-making efforts by a joint Russian-American research team developing a community, national, and international response to industrial contamination. Bobovnikova et al. have reported that PCBs are elevated in soils and sediments, breast milk, and locally grown foods in the Serpukhov area. Data from these and other investigators have been used in this risk assessment to calculate a potential cancer risk resulting from exposure to PCBs. Their assessment indicates that members of the local population may be at increased risk of cancer, and possibly other adverse health effects, as a result of PCB contamination of their environment. Because previously unassessed environmental contamination is a common problem in the former Soviet Republics, as well as many other areas of the world, the authors believe this type of evaluation, using known methods, can serve as a model for assessment efforts in other parts of the globe and result in remediative efforts in regions constrained by faltering economies.

  9. Engineering Issue: Technology Alternatives for the Remediation of PCB Contaminated Soils and Sediments

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) Engineering Issue papers are a series of documents that summarize the available information on specific contaminates, selected treatment and site remediation technologies, and related issues. This Engineering Issue paper is intended...

  10. PCB dechlorination in anaerobic soil slurry reactors

    SciTech Connect

    Klasson, K.T.; Evans, B.S.

    1993-11-29

    Many industrial locations, including the US Department of Energy`s, have identified needs for treatment of polychlorinated biphenyl (PCB) wastes and remediation of PCB-contaminated sites. Biodegradation of PCBs is a potentially effective technology for the treatment of PCB-contaminated soils and sludges, including mixed wastes; however, a practical remediation technology has not yet been demonstrated. In laboratory experiments, soil slurry bioreactors inoculated with microorganisms extracted from PCB-contaminated sediments from the Hudson River have been used to obtain anaerobic dechlorination of PCBS. The onset of dechlorination activity can be accelerated by addition of nutritional amendments and inducers. After 15 weeks of incubation with PCB-contaminated soil and nutrient solution, dechlorination has been observed under several working conditions. The best results show that the average chlorine content steadily dropped from 4.3 to 3.5 chlorines per biphenyl over a 15-week period.

  11. Laboratory Study of Polychlorinated Biphenyl (PCB) Contamination and Mitigation in Buildings -- Part 4. Evaluation of the Activated Metal Treatment System (AMTS) for On-site Destruction of PCBs

    EPA Science Inventory

    This is the fourth, also the last, report of the report series entitled “Laboratory Study of Polychlorinated Biphenyl (PCB) Contamination and Mitigation in Buildings.” This report evaluates the performance of an on-site PCB destruction method, known as the AMTS method, developed ...

  12. Determinants of polychlorinated biphenyls (PCBs) in the sera of mothers and children from Michigan farms with PCB-contaminated silos

    SciTech Connect

    Schantz, S.L.; Jacobson, J.L.; Jacobson, S.W.; Humphrey, H.E.B.; Welch, R.; Gasior, D.

    1994-11-01

    Blood samples were collected from 28 mothers and from 38 school-aged children from Michigan farms on which there were polychlorinated biphenyl (PCB)-contaminated silos. The samples were analyzed for PCBs and other contaminants, including polybrominated biphenyls (PBBs) and dichlorodiphenyl trichloroethane (p,p{prime}-DDT + p,p{prime}-DDE) via packed column gas chromatography. The PCBs were quantified, using the Webb-McCall method, with Aroclors 1016 and 1260 used as reference standards. Approximately 42% of the children had serum PCB levels above the detection limit of 3.0 ng/ml. The values ranged from 3.1 to 23.3 ng/ml, with a mean of 6.8 ng/ml. In contrast, PCBs were detected in 86% of the mothers. The mean serum concentration was somewhat higher for the mothers (9.6 ng/ml), but the range was similar to that found for the children. PBBs were not detected in any of the children, but were present in trace amounts in 25% of the mothers. Conversely, DDT was present in 66% of the children and 93% of the mothers. As with PCBs, DDT concentrations were somewhat higher in the mothers. DDE accounted for 89% of the total DDT in serum. Various potential sources of exposure were evaluated as possible determinants of serum PCB levels, using hierarchical multiple regression. Years of residence on a silo farm and consumption of PCB-contaminated Great Lakes fish both accounted for significant portions of the variance in maternal serum PCB levels. Exposure via breast-feeding explained a large and highly significant proportion of the variance in the children`s serum PCB concentrations, suggesting that breast milk was the primary source of PCB exposure for these children. Years of residence on a silo farm also explained a significant proportion of the variance in children`s serum PCBs. 29 refs., 1 fig., 5 tabs.

  13. CHOL-N-SOIL PCB TEST KIT, DEXSIL CORP. - INNOVATIVE TECHNOLOGY Evaluation REPORT

    EPA Science Inventory

    This innovative technology evaluation report (ITER) presents the evaluation of two field screening technologies for determining polychlorinated biphenyl (PCB) contamination in soil. The demonstration was conducted by PRC Environmental Management, Inc. (PRC), under contract to the...

  14. DEVELOPING TOOLS FOR MONITORED NATURAL RECOVERY OF PCB-CONTAMINATED SEDIMENTS AT LAKE HARTWELL, SC

    EPA Science Inventory

    Contaminated sediments pose a risk to human health and the environment . The management of this risk is currently limited practically to three technologies: dredging, capping, and natural recovery. Monitored natural recovery relies on the natural burial and removal mechanisms to...

  15. Effects of activated carbon ageing in three PCB contaminated sediments: Sorption efficiency and secondary effects on Lumbriculus variegatus.

    PubMed

    Nybom, Inna; Waissi-Leinonen, Greta; Mäenpää, Kimmo; Leppänen, Matti T; Kukkonen, Jussi V K; Werner, David; Akkanen, Jarkko

    2015-11-15

    The sorption efficiency and possible secondary effects of activated carbon (AC) (ø 63-200 μm) was studied with Lumbriculus variegatus in three PCB contaminated sediments applying long AC-sediment contact time (3 years). AC amendment efficiently reduced PCB bioavailability as determined with both, L. variegatus bioaccumulation test and passive samplers. However, dose related secondary effects of AC on egestion rate and biomass were observed (applied doses 0.25% and 2.5% sediment dry weight). The sorption capacity and secondary effects remained similar when the experiments were repeated after three years of AC-sediment contact time. Further, transmission electron microscopy (TEM) samples revealed morphological changes in the L. variegatus gut wall microvilli layer. Sediment properties affected both sorption efficiency and secondary effects, but 2.5% AC addition had significant effects regardless of the sediment. In, conclusion, AC is an efficient and stable sorbent to decrease the bioavailability of PCBs. However, sediment dwelling organisms, such as Oligochaete worms in this study, may be sensitive to the carbon amendments. The secondary effects and possible morphological changes in benthic organisms should not be overlooked as in many cases they form the basis of the aquatic food webs. PMID:26364225

  16. TOOLS FOR ASSESSING MONITORED NATURAL RECOVERY OF PCB-CONTAMINATED SEDIMENTS

    EPA Science Inventory

    Management of contaminated sediments poses many challenges due to varied contaminants and volumes of sediments to manage. dredging, capping, and monitored natural recovery (MNR) are the primary approaches at this time for managing contaminated sediment risks. Understanding how we...

  17. Toxic potencies of lipophilic extracts from sediments and settling particulate matter (SPM) collected in a PCB-contaminated river system

    SciTech Connect

    Engwall, M.; Brunstroem, B.; Broman, D.; Ishaq, R.; Naef, C.; Zebuehr, Y.

    1996-02-01

    Sediments and settling particulate matter (SPM) were sampled in a PCB-contaminated lake, Lake Jaernsjoen, and in lakes located up- and downstream from Lake Jaernsjoen. The 7-ethoxyresorufin O-deethylase (EROD)-inducing potencies of lipophilic extracts from sediment and SPM were investigated in organ cultures of chicken embryo livers (denoted in vitro chicken embryo liver bioassay). The extract from sediments collected in Lake Jaernsjoen had the greatest EROD-inducing potency of the extracts studied, and it also contained the highest concentrations of PCBs, PAHs, and polychlorinated dibenzodioxins/furans (PCDDs/Fs). The non-ortho-chlorinated PCBs in the extracts were probably major contributors to the EROD induction noted. The EROD-inducing potency of sediment extract from the lake downstream Lake Jaernsjoen was higher than that of extract from the upstream lake. This indicates that EROD-inducing substances were transported from Lake Jaernsjoen sediment to the lake downstream. The extracts from Lake Jaernsjoen sediment and SPM were separated into three fractions containing aliphatic/monoaromatic, diaromatic, and polyaromatic compounds, respectively, which were tested in the in vitro chicken embryo liver bioassay. In all extracts, the aliphatic/monoaromatic fractions were low in EROD-inducing potency, while the polyaromatic fractions from SPM were more potent than their corresponding diaromatic fractions, indicating that they contained high concentrations of aromatic hydrocarbon (Ah) receptor ligands. Only a small part of the EROD induction caused by the polyaromatic fractions could be attributed to the 15 analyzed PAHs in the samples. The EROD-inducing potencies of the diaromatic fractions correlated quite well with their concentrations of PCDDs/Fs and PCBs. The in vitro chicken embryo liver bioassay detected low concentrations of EROD inducers in the extracts and therefore proved useful for estimating the contents of Ah receptor ligands in environmental shapes.

  18. Application of the base catalyzed decomposition process to treatment of PCB-contaminated insulation and other materials associated with US Navy vessels. Final report

    SciTech Connect

    Schmidt, A.J.; Zacher, A.H.; Gano, S.R.

    1996-09-01

    The BCD process was applied to dechlorination of two types of PCB-contaminated materials generated from Navy vessel decommissioning activities at Puget Sound Naval Shipyard: insulation of wool felt impregnated with PCB, and PCB-containing paint chips/debris from removal of paint from metal surfaces. The BCD process is a two-stage, low-temperature chemical dehalogenation process. In Stage 1, the materials are mixed with sodium bicarbonate and heated to 350 C. The volatilized halogenated contaminants (eg, PCBs, dioxins, furans), which are collected in a small volume of particulates and granular activated carbon, are decomposed by the liquid-phase reaction (Stage 2) in a stirred-tank reactor, using a high-boiling-point hydrocarbon oil as the reaction medium, with addition of a hydrogen donor, a base (NaOH), and a catalyst. The tests showed that treating wool felt insulation and paint chip wastes with Stage 2 on a large scale is feasible, but compared with current disposal costs for PCB-contaminated materials, using Stage 2 would not be economical at this time. For paint chips generated from shot/sand blasting, the solid-phase BCD process (Stage 1) should be considered, if paint removal activities are accelerated in the future.

  19. Soil-ecological risks for soil degradation estimation

    NASA Astrophysics Data System (ADS)

    Trifonova, Tatiana; Shirkin, Leonid; Kust, German; Andreeva, Olga

    2016-04-01

    Soil degradation includes the processes of soil properties and quality worsening, primarily from the point of view of their productivity and decrease of ecosystem services quality. Complete soil cover destruction and/or functioning termination of soil forms of organic life are considered as extreme stages of soil degradation, and for the fragile ecosystems they are normally considered in the network of their desertification, land degradation and droughts /DLDD/ concept. Block-model of ecotoxic effects, generating soil and ecosystem degradation, has been developed as a result of the long-term field and laboratory research of sod-podzol soils, contaminated with waste, containing heavy metals. The model highlights soil degradation mechanisms, caused by direct and indirect impact of ecotoxicants on "phytocenosis- soil" system and their combination, frequently causing synergistic effect. The sequence of occurring changes here can be formalized as a theory of change (succession of interrelated events). Several stages are distinguished here - from heavy metals leaching (releasing) in waste and their migration downward the soil profile to phytoproductivity decrease and certain phytocenosis composition changes. Phytoproductivity decrease leads to the reduction of cellulose content introduced into the soil. The described feedback mechanism acts as a factor of sod-podzolic soil self-purification and stability. It has been shown, that using phytomass productivity index, integrally reflecting the worsening of soil properties complex, it is possible to solve the problems dealing with the dose-reflecting reactions creation and determination of critical levels of load for phytocenosis and corresponding soil-ecological risks. Soil-ecological risk in "phytocenosis- soil" system means probable negative changes and the loss of some ecosystem functions during the transformation process of dead organic substance energy for the new biomass composition. Soil-ecological risks estimation is

  20. REMEDIATION OF PCB IN CONTAMINATED SOIL

    EPA Science Inventory

    A pilot-scale study will be conducted to evaluate the bioremedial techniques of natural attenuation, sequenced anaerobic/aerobic treatment, and addition of a commercially available microbial amendment product for use in treating PCB contaminated soils at Air Force Base sites. Th...

  1. Sequential anaerobic-aerobic degradation of indigenous PCBs in a contaminated soil matrix

    SciTech Connect

    Klasson, K.T.; Reeves, M.E.; Evans, B.S.; Dudley, C.A.

    1994-12-31

    Many industrial locations, including the US Department of Energy`s, have identified needs for treatment of polychlorinated biphenyl (PCB) wastes and remediation of PCB-contaminated sites. Biodegradation of PCBs is a potentially effective technology for the treatment of PCB-contaminated soils and sludges; however, a practicable remediation technology has not yet been demonstrated. A biological treatment technology is likely to consist of an anaerobic fermentation step in which PCB dechlorination takes place producing PCBs with fewer chlorines. These products are then more susceptible to aerobic mineralization. In laboratory experiments, soil slurry bioreactors inoculated with microorganisms extracted from PCB-contaminated sediments from the Hudson River and Woods Pond have been used to obtain anaerobic dechlorination of PCBs in soil slurry reactors. The anaerobic dechlorination was followed by qualitative estimation of the effect of aerobic fermentation of the dechlorination products based on literature data. The sequential anaerobic-(simulated) aerobic treatment constituted an improvement compared anaerobic treatment alone.

  2. A PHYSICAL, CHEMICAL, AND BIOLOGICAL ASSESSMENT OF MONITORED NATURAL RECOVERY OF PCB-CONTAMINATED SEDIMENTS IN LAKE HARTWELL, CLEMSON, NC

    EPA Science Inventory

    Management of contaminated sediments poses significant challenges due to varied contaminants and volumes of sediments to manage. Dredging, capping, and monitored natural recovery (MNR) are the primary approaches for managing the contaminated sediment risks. Understanding how eff...

  3. PHYSICAL, CHEMICAL AND BIOLOGICAL TOOLS FOR EVALUATING, MONITORED NATURAL RECOVERY OF PCB CONTAMINATED SEDIMENTS IN LAKE HARTWELL, CLEMSON, SC

    EPA Science Inventory

    Management of contaminated sediments poses significant challenges due to varied contaminants and volumes of sediments to
    manage. Dredging, capping, and monitored natural recovery (MNR) are the primary approaches for managing the contaminated sediment risks.
    Understanding ho...

  4. Extinction risk of soil biota.

    PubMed

    Veresoglou, Stavros D; Halley, John M; Rillig, Matthias C

    2015-01-01

    No species lives on earth forever. Knowing when and why species go extinct is crucial for a complete understanding of the consequences of anthropogenic activity, and its impact on ecosystem functioning. Even though soil biota play a key role in maintaining the functioning of ecosystems, the vast majority of existing studies focus on aboveground organisms. Many questions about the fate of belowground organisms remain open, so the combined effort of theorists and applied ecologists is needed in the ongoing development of soil extinction ecology. PMID:26593272

  5. Extinction risk of soil biota

    PubMed Central

    Veresoglou, Stavros D.; Halley, John M.; Rillig, Matthias C.

    2015-01-01

    No species lives on earth forever. Knowing when and why species go extinct is crucial for a complete understanding of the consequences of anthropogenic activity, and its impact on ecosystem functioning. Even though soil biota play a key role in maintaining the functioning of ecosystems, the vast majority of existing studies focus on aboveground organisms. Many questions about the fate of belowground organisms remain open, so the combined effort of theorists and applied ecologists is needed in the ongoing development of soil extinction ecology. PMID:26593272

  6. EMERGING TECHNOLOGY REPORT: BENCH-SCALE TESTING OF PHOTOLYSIS, CHEMICAL OXIDATION AND BIODEGRADATION OF PCB CONTAMINATED SOILS AND PHOTOLYSIS OF TCDD CONTAMINATED SOILS

    EPA Science Inventory

    This report presents the results of bench-scale testing on degradation of 2,3,7,8-TCDD using W photolysis, and PCB degradation using UV photolysis, chemical oxidation and biological treatment. Bench-scale tests were conducted to investigate the feasibility of a two-phase detoxifi...

  7. Ecological risk assessment of contaminated soil.

    PubMed

    Jensen, John; Pedersen, Marianne Bruus

    2006-01-01

    This review has described three cases of ecological risk assessment. The cases include two heavy metals (Cu and Zn) and an anthropogenic organic chemical (DDT). It concludes that there are at least two major constraints hampering the use of laboratory tests to predict effects under natural field conditions. One key issue is bioavailability, and another is suboptimal conditions or multiple stresses in the field such as climatic stress (drought, frost), predators, competition, or food shortage. On the basis of the presented case studies, it was possible to answer three essential questions often raised in connection to ecological risk assessment of contaminated sites. 1. To what extend does soil screening level (SSL) estimate the risk? The SSL are generally derived at levels corresponding to the lowest observed effect levels in laboratory studies, which often is close to the background levels found in many soils. In the cases of zinc and especially DDT, the SSL seemed quite conservative, whereas for copper they resemble the level at which changes in the community structure of soil microarthropods and the plant community have been observed at contaminated sites. The SSL correspond as a whole relatively well with concentrations where no effects or only minor effects were observed in controlled field studies. However, large variation in field surveys can often make it difficult to conclude to what extent the SSL corresponded to no-effect levels in the field. 2. Do bioassays represent a more realistic risk estimate? Here, there is no firm conclusion. The zinc study in UK showed a better relationship between the outcome of ex situ bioassays and field observations than the SSL. The latter overestimated the risk compared to field observations. However, this would be species dependent, as the sensitivity to metals may vary considerably between recognized test species, even within the same group of organisms, such as Folsomia candida and Folsomia fimetaria or Eisenia fetida

  8. Estimated soil ingestion rates for use in risk assessment

    SciTech Connect

    LaGoy, P.K.

    1987-09-01

    Assessing the risks to human health posed by contaminants present in soil requires an estimate of likely soil ingestion rates. In the past, direct measurements of soil ingestion were not available and risk assessors were forced to estimate soil ingestion rates based on observations of mouthing behavior and measurements of soil on hands. Recently, empirical data on soil ingestion rates have become available from two sources. Although preliminary, these data can be used to derive better estimates of soil ingestion rates for use in risk assessments. Estimates of average soil ingestion rates derived in this paper range from 25 to 100 mg/day, depending on the age of the individual at risk. Maximum soil ingestion rates that are unlikely to underestimate exposure range from 100 to 500 mg. A value of 5000 mg/day is considered a reasonable estimate of a maximum single-day exposure for a child with habitual pica. 12 references.

  9. The use of biochar to reduce soil PCB bioavailability to Cucurbita pepo and Eisenia fetida.

    PubMed

    Denyes, Mackenzie J; Langlois, Valérie S; Rutter, Allison; Zeeb, Barbara A

    2012-10-15

    Biochar is a carbon rich by-product produced from the thermal decomposition of organic matter under low oxygen concentrations. Currently many researchers are studying the ability of biochar to improve soil quality and function in agricultural soils while sustainably sequestering carbon. This paper focuses on a novel but complimentary application of biochar - the reduced bioavailability and phytoavailability of organic contaminants in soil, specifically polychlorinated biphenyls (PCBs). In this greenhouse experiment, the addition of 2.8% (by weight) biochar to soil contaminated with 136 and 3.1 μg/g PCBs, reduced PCB root concentration in the known phytoextractor Cucurbita pepo ssp. pepo by 77% and 58%, respectively. At 11.1% biochar, even greater reductions of 89% and 83% were recorded, while shoot reductions of 22% and 54% were observed. PCB concentrations in Eisenia fetida tissue were reduced by 52% and 88% at 2.8% and 11.1% biochar, respectively. In addition, biochar amended to industrial PCB-contaminated soil increased both aboveground plant biomass, and worm survival rates. Thus, biochar has significant potential to serve as a mechanism to decrease the bioavailability of organic contaminants (e.g. PCBs) in soil, reducing the risk these chemicals pose to environmental and human health, and at the same time improve soil quality and decrease CO(2) emissions. PMID:22922132

  10. [Homologues Levels and Distribution Pattern of Polychlorinated Biphenyls in Typical Capacitor Contaminated Soil].

    PubMed

    Liu, Jie; Li, Xiao-dong; Zhao, Zhong-hua; Qi, Zhi-fu; Chen, Tong; Yan, Jian-hua

    2015-09-01

    The homologues levels, distribution characteristics and TEQ of 209 PCBs in soil collected around 3 storage sites of PCB-containing wastes were investigated. The PCBs contents and environmental risk were evaluated to provide a scientific basis for site remediation of PCBs contaminated soil. Totally 12 soil samples were collected from 3 PCB-contaminated sites. The analysis results showed that the PCB-concentration in Soil A was 1 705. 0 µg.g-1 ± 424. 3 µg.g-1 (n =4), higher than Soil B (233. 0 µg.g-1 ± 80. 0, n = 4) and Soil C (225. 7 µg.g-1 ± 90. 2 µg.g-1, n = 4), indicating the soil was heavily polluted by PCBs. Trichlorobiphenyl and Tetrachlorobiphenyl dominated the homologues of PCBs. The mass fraction of chlorine in Soil A, Soil B and Soil C was 43. 7% 1. 0%, 45.5% ± 0. 5% and 44.9% ± 0.3%, respectively, which was similar as Aroclor1242 and l#PCB insulating oil. There was an obvious linear correlation between indicator PCBs and total PCBs (R2 = 0. 998), so indicator PCBs can be used to estimate the level of total PCBs. PCB77, PCB105, PCB118 were predominant in doxin-like PCBs, accounting for 89. 5% ± 4. 0% in total. The TEQ levels of the soil samples (in WHO-TEQ) were 3. 56-63. 55 ng.g-1, which demonstrated a high environmental risk in the area. PCB28/31, PCB33/20, PCB66/80, PCB70, PCB32 and PCB18 were the main PCBs isomers. Compared with other results, the local soil was heavily contaminated by PCBs and the surroundings were under a relatively high risk of environmental contamination. PMID:26717710

  11. AN IMPROVED UNDERSTANDING OF SOIL CD RISK TO HUMANS AND LOW COST METHODS TO PHYTOEXTRACT CD FROM CONTAMINATED SOILS TO PREVENT SOIL CD RISKS

    EPA Science Inventory

    We have described a new paradigm for human risk from soil Cd that reflects many years of agronomic, nutritional and toxicological research. This new model for soil Cd risk reflects the ability of rice to accumulate soil Cd in grain while excluding Fe, Zn and Ca even though the s...

  12. Comprehensive methodology for ecological risk assessment of contaminated soils

    SciTech Connect

    Kuperman, R.G.

    1994-12-31

    Development of a comprehensive methodology for ecological risk assessment and monitoring of contaminated soils is essential to assess the impacts of environmental contaminants on soil community and biologically-mediated processes in soil. The proposed four-step plan involves (1) a thorough survey of the soil community to establish biodiversity and a base-line community structure, (2) toxicity trials on indicator species and whole soil invertebrate communities, (3) laboratory and field tests on indicator processes and (4) the use of statistical and simulation models to ascertain changes in the soil ecosystems. This methodology was used in portions of the US Army`s Aberdeen Proving Ground, Maryland as part of an ecological risk assessment. Previous soil analyses showed extensive surface soil contamination with metals, nitrate and PCBs. Preliminary results from field surveys of soil invertebrate communities showed significant reductions in total abundance of animals, reductions in the abundance of several taxonomic and functional groups of soil invertebrates, and changes in the activity of epigeic arthropods in contaminated areas when compared with the local ``background`` area. Laboratory tests also demonstrated that microbial activity and success of egg hatching of ground beetle Harpalus pensylvanicus were reduced in contaminated soils. These results suggest that impacts to soil ecosystems should be explicitly considered in ecological risk assessment. The proposed comprehensive methodology appears to offer an efficient and potentially cost saving tool for remedial investigations of contaminated sites.

  13. CORRELATING METAL SPECIATION IN SOILS TO RISK

    EPA Science Inventory

    Understanding bioavailability of metals from exposure to contaminated soils is a challenging aspect of environmental research. This presentation will examine three areas of research with respect to metal speciation in soils as it relates to bioavailability: 1) Pb immobilization a...

  14. Reductive microbial dechlorination of indigenous polychlorinated biphenyls in soil using a sediment-free inoculum.

    PubMed

    Klasson, K T; Barton, J W; Evans, B S; Reeves, M E

    1996-01-01

    In laboratory experiments, unagitated soil slurry bioreactors inoculated with micro-organisms extracted from polychlorinated biphenyl-contaminated (PCBs) sediments from the Hudson River were used to anaerobically dechlorinate PCBs. The onset of dechlorination activity was accelerated by the addition of certain organic acids (pyruvate and maleate) and single congeners (2,3,6-trichlorobiphenyl). Dechlorination was observed under several working conditions after 19 weeks of incubation with PCB-contaminated soil and nutrient solution. Best results showed a drop in average chlorine content from 4.3 to 3.6 chlorines per biphenyl due to a loss of m-chlorines. Soil used for these experiments was obtained from a PCB-contaminated (weathered Aroclor 1248) site at an electric power substation. Dechlorination was observed with no sediment particles or other matrix being added. PMID:8652118

  15. Reductive microbial dechlorination of indigenous polychlorinated biphenyls in soil using a sediment-free inoculum

    SciTech Connect

    Klasson, K.T.; Barton, J.W.; Evans, B.S.; Reeves, M.E.

    1996-05-01

    In laboratory experiments, unagitated soil slurry bioreactors inoculated with microorganisms extracted from polychlorinated biphenyl-contaminated (PCBs) sediments from the Hudson River were used to anaerobically dechlorinate PCBs. The onset of dechlorination activity was accelerated by the addition of certain organic acids (pyruvate and maleate) and single congeners (2,3,6-trichlorobiphenyl). Dechlorination was observed under several working conditions after 19 weeks of incubation with PCB-contaminated soil and nutrient solution. Best results showed a drop in average chlorine content from 4.3 to 3.6 chlorines per biphenyl due to a loss of m-chlorines. Soil used for these experiments was obtained from a PCB-contaminated (weathered Aroclor 1248) site at an electric power substation. Dechlorination was observed with no sediment particles or other matrix being added. 17 refs., 6 figs., 1 tab.

  16. Dechlorination of polychlorinated biphenyl-contaminated soil via anaerobic composting with pig manure.

    PubMed

    Zhang, Chi; Du, Yao; Tao, Xiao-Qing; Zhang, Kun; Shen, Dong-Sheng; Long, Yu-Yang

    2013-10-15

    Anaerobic dechlorination is an effective degradation pathway of higher chlorinated polychlorinated biphenyls (PCBs). The efficiency of anaerobic composting remediation of PCB-contaminated soil using pig manure was determined. The results show that the dechlorination of PCB-contaminated soil via anaerobic composting with pig manure is feasible. PCB concentration is the most critical factor. Elevated PCB concentrations can inhibit dechlorination but does not disrupt the anaerobic fermentation process. At 1 mg kg(-1) PCBs, the degradation rate of five or more chlorinated biphenyls is 43.8%. The highest dechlorination performance in this experiment was obtained when the soil-to-organic waste ratio, carbon-to-nitrogen ratio, moisture content, and PCB concentration were 2:3, 20, 60%, and 1 mg kg(-1), respectively. PMID:23910395

  17. Combined effect of microwave and activated carbon on the remediation of polychlorinated biphenyl-contaminated soil.

    PubMed

    Liu, Xitao; Yu, Gang

    2006-04-01

    The application of microwave and activated carbon for the treatment of polychlorinated biphenyl (PCB) contaminated soil was explored in this study with a model compound of 2,4,5-trichlorobiphenyl (PCB29). PCB-contaminated soil was treated in a quartz reactor by microwave irradiation at 2450MHz with the addition of granular activated carbon (GAC). In this procedure, GAC acted as microwave absorbent for reaching high temperature and reductant for dechlorination. A sheltered type-K thermocouple was applied to record the temperature rising courses. It was shown that the addition of GAC could effectively promote the temperature rising courses. The determination of PCB residues in soil by gas chromatography (GC) revealed that rates of PCB removal were highly dependent on microwave power, soil moisture content, and the amount of GAC added. GC with mass spectrum (MS) detector and ion chromatography were employed for the analysis of degradation intermediates and chlorine ions, respectively. It was suggested that microwave irradiation with the assistance of activated carbon might be a potential technology for the remediation of PCB-contaminated soil. PMID:16213557

  18. Urban Community Gardeners' Knowledge and Perceptions of Soil Contaminant Risks

    PubMed Central

    Kim, Brent F.; Poulsen, Melissa N.; Margulies, Jared D.; Dix, Katie L.; Palmer, Anne M.; Nachman, Keeve E.

    2014-01-01

    Although urban community gardening can offer health, social, environmental, and economic benefits, these benefits must be weighed against the potential health risks stemming from exposure to contaminants such as heavy metals and organic chemicals that may be present in urban soils. Individuals who garden at or eat food grown in contaminated urban garden sites may be at risk of exposure to such contaminants. Gardeners may be unaware of these risks and how to manage them. We used a mixed quantitative/qualitative research approach to characterize urban community gardeners' knowledge and perceptions of risks related to soil contaminant exposure. We conducted surveys with 70 gardeners from 15 community gardens in Baltimore, Maryland, and semi-structured interviews with 18 key informants knowledgeable about community gardening and soil contamination in Baltimore. We identified a range of factors, challenges, and needs related to Baltimore community gardeners' perceptions of risk related to soil contamination, including low levels of concern and inconsistent levels of knowledge about heavy metal and organic chemical contaminants, barriers to investigating a garden site's history and conducting soil tests, limited knowledge of best practices for reducing exposure, and a need for clear and concise information on how best to prevent and manage soil contamination. Key informants discussed various strategies for developing and disseminating educational materials to gardeners. For some challenges, such as barriers to conducting site history and soil tests, some informants recommended city-wide interventions that bypass the need for gardener knowledge altogether. PMID:24516570

  19. Urban community gardeners' knowledge and perceptions of soil contaminant risks.

    PubMed

    Kim, Brent F; Poulsen, Melissa N; Margulies, Jared D; Dix, Katie L; Palmer, Anne M; Nachman, Keeve E

    2014-01-01

    Although urban community gardening can offer health, social, environmental, and economic benefits, these benefits must be weighed against the potential health risks stemming from exposure to contaminants such as heavy metals and organic chemicals that may be present in urban soils. Individuals who garden at or eat food grown in contaminated urban garden sites may be at risk of exposure to such contaminants. Gardeners may be unaware of these risks and how to manage them. We used a mixed quantitative/qualitative research approach to characterize urban community gardeners' knowledge and perceptions of risks related to soil contaminant exposure. We conducted surveys with 70 gardeners from 15 community gardens in Baltimore, Maryland, and semi-structured interviews with 18 key informants knowledgeable about community gardening and soil contamination in Baltimore. We identified a range of factors, challenges, and needs related to Baltimore community gardeners' perceptions of risk related to soil contamination, including low levels of concern and inconsistent levels of knowledge about heavy metal and organic chemical contaminants, barriers to investigating a garden site's history and conducting soil tests, limited knowledge of best practices for reducing exposure, and a need for clear and concise information on how best to prevent and manage soil contamination. Key informants discussed various strategies for developing and disseminating educational materials to gardeners. For some challenges, such as barriers to conducting site history and soil tests, some informants recommended city-wide interventions that bypass the need for gardener knowledge altogether. PMID:24516570

  20. LONG-TERM RECOVERY OF PCB-CONTAMINATED SURFACE SEDIMENTS AT THE SANGAMO-WESTON/TWELVEMILE CREEK/LAKE HARTWELL SUPERFUND SITE

    EPA Science Inventory

    Natural recovery of contaminated sediments relies on burial of contaminated sediments with increasingly clean sediments over time (i.e., natural capping). Natural capping reduces the risk of resuspension of contaminated surface sediments, and it reduces the potential for contamin...

  1. A MULTI-ORD LAB AND REGIONAL ASSESSMENT OF MONITORED NATURAL RECOVERY OF PCB-CONTAMINATED SEDIMENTS IN LAKE HARTWELL, CLEMSON, SC

    EPA Science Inventory

    Management of contaminated sediments poses many challenges due to varied contaminants and volumes of sediments to manage. Dredging, capping, and monitored natural recovery (MNR) are the primary approaches for managing the contaminated sediment risks. Understanding how well the ...

  2. Risk assessment of soil compaction in Walloon Region (Belgium)

    NASA Astrophysics Data System (ADS)

    Charlotte, Rosiere; Marie-France, Destain; Jean-Claude, Verbrugge

    2010-05-01

    The proposed Soil Framework Directive COM(2006)232 requires Member States to identify areas at risk of erosion, decline in organic matter, salinisation, compaction, sealing and landslides, as well as to set up an inventory of contaminated sites. The present project aims to identify the susceptibility to compaction of soils of the Walloon Region (Belgium) and to recommend good farming practices avoiding soil compaction as far as possible. Within this scope, the concept of precompression stress (Pc) (Horn and Fleige, 2003) was used. Pc is defined as the maximum major principal stress that a soil horizon can withstand against any applied external vertical stress. If applied stress is higher than Pc, the soil enters in a plastic state, not easily reversible. For a given soil, the intensity of soil compaction is mainly due to the applied load which depends on vehicle characteristics (axle load, tyre dimensions, tyre inflation pressure, and vehicle velocity). To determine soil precompression stress, pedotransfert functions of Lebert and Horn (1991) defined at two water suctions (pF 1.8 and 2.5) were used. Parameters required by these functions were found within several databases (Aardewerk and Digital Map of Walloon Soils) and literature. The validation of Pc was performed by measuring stress-strain relationships using automatic oedometers. Stresses of 15.6, 31, 3, 62.5, 125, 250, 500 and 1000 kPa were applied for 10 min each. In this study, the compaction due to beet harvesters was considered because the axle load can exceed 10 tons and these machines are often used during wet conditions. The compaction at two depth levels was considered: 30 and 50 cm. Compaction of topsoil was not taken into account because, under conventional tillage, the plough depth is lower than 25 cm. Before and after the passage of the machines, following measurements were performed: granulometry, density, soil moisture, pF curve, Atterberg limits, ... The software Soilflex (Keller et al., 2007

  3. An improved understanding of soil Cd risk to humans and low cost methods to phytoextract Cd from contaminated soils to prevent soil Cd risks.

    PubMed

    Chaney, Rufus L; Reeves, Philip G; Ryan, James A; Simmons, Robert W; Welch, Ross M; Angle, J Scott

    2004-10-01

    We believe greater consideration should be given the agronomic and nutritional/bioavailability factors that influence risk from Cd-contaminated soils. We have argued that the ability of rice to accumulate soil Cd in grain while excluding Fe, Zn and Ca (even though the soil contains 100-times more Zn than Cd) was important in adverse effects of soil Cd is farm families in Asia. Further, polished rice grain is deficient in Fe, Zn and Ca for humans, which promotes Cd absorption into duodenal cells. New kinetic studies clarified that dietary Cd is absorbed into duodenum enterocytes; 109Cd from a single meal remained in the duodenum for up to 16 days; part of the turnover pool 109Cd moved to the liver and kidneys by the end of the 64-day 'chase' period. Thus malnutrition induced by subsistence rice diets caused a higher absorption of dietary Cd and much higher potential risk from soil Cd than other crops. Because rice-induced Fe-Zn-Ca-malnutrition is so important in soil Cd risk, it seems evident that providing nutritional supplements to populations of exposed subsistence rice farmers could protect them against soil Cd during a period of soil remediation. In the long term, high Cd rice soils need to be remediated. Remediation by removal and replacement of contaminated soil is very expensive (on the order of $3 million/ha); while phytoextraction using the high Cd accumulating ecotypes of the Zn-Cd hyperaccumulator, Thlaspi caerulescens, should provide low cost soil Cd remediation. PMID:15688862

  4. Long-Term Recovery of PCB-Contaminated Surface Sediments at the Sangamo-Weston / Twelvemile Creek / Lake Hartwell Superfund Site

    SciTech Connect

    Brenner, Richard C.; Magar, Victor S.; Ickes, Jennifer A.; Foote, Eric A.; Abbott, James E.; Bingler, Linda S.; Crecelius, Eric A.

    2004-03-10

    Natural recovery of contaminated sediments relies on burial of contaminated sediments with increasingly clean sediments over time (i.e., natural capping). Natural capping reduces the risk of resuspension of contaminated surface sediments, and it reduces the potential for contaminant transport into the food chain by limiting bioturbation of contaminated surface or near-surface sediments. This study evaluated the natural recovery of surface sediments contaminated with polychlorinated biphenyls (PCBs) at the Sangamo-Weston/Twelvemile Creek/Lake Hartwell Superfund Site (Lake Hartwell), Pickens County, SC. The primary focus was on sediment recovery resulting from natural capping processes. Total PCB (t-PCB), lead-210 (210Pb), and cesium-137 (137Cs) sediment core profiles were used to establish vertical t-PCB concentration profiles, age date sediments, and determine surface sedimentation and surface sediment recovery rates in 18 cores collected along 10 transects. Four upgradient transects in the headwaters of Lake Hartwell were impacted by historical sediment releases from three upgradient sediment impoundments. These transects were characterized by silt/ clay and sand layering. The highest PCB concentrations were associated with silt/clay layers (1.8-3.5% total organic carbon (TOC)), while sand layers (0.05-0.32% TOC) contained much lower PCB concentrations. The historical sediment releases resulted in substantial burial of PCBcontaminated sediment in the vicinity of these four cores; each core contained less than 1 mg/kg t-PCBs in the surface sand layers. Cores collected from six downgradient Lake Hartwell transects consisted primarily of silt and clay (0.91-5.1% TOC) and were less noticeably impacted by the release of sand from the impoundments. Vertical t-PCB concentration profiles in these cores began with relatively low PCB concentrations at the sediment-water interface and increased in concentration with depth until maximum PCB concentrations were measured at _30

  5. RISK ASSESSMENT OF DIOXINS ON SOIL INHABITANTS IN JAPAN - VERIFICATION AND PROPOSAL -

    NASA Astrophysics Data System (ADS)

    Hase, Emiko; Kitano, Masaru; Kawabe, Yoshishige; Komai, Takeshi

    Soil environmental assessment is a great importance for the protection of soil biodiversity. Environmental risk of dioxins on earthworm and soil microorganism was evaluated to propose a new soil risk assessment standard. The proposed approach in this study may be a useful tool for precautionary approach and management for soil and ground water contamination in Japan. The procedure consists of exposure assessment, effects assessment and risk evaluation. In the exposure assessment, Predicted Environmental Concentration (PEC) for soil, hereby PECsoil, was calculated. In the effects assessment, Predicted non-Effects Concentration (PNEC) for soil invertebrate and microorganisms, hereby PNECsoil and PNECsoilmicroorg, were calculated. Risk Characterization Ratio (RCR; ratio of PECsoil and PNECsoil, and PEC soil and PNECsoilmicroorg.) for dioxins were applied to quantify the level of risk. Under the assumption that RCR is 1, the risk-based soil concentration limits (allowance levels) were calculated to be up to 885 pg-TEQ/g for earthworm and to be 998,000 pg-TEQ/g soil for soil microorganism. This means that the risk level to representative soil invertebrates and microorganisms could be tolerable when the soil concentration was below these values. We propose this risk assessment method as one of measures to investigate, estimate and evaluate the soil biodiversity so that proper risk management measures are conducted and then biodiversity is preserved forever.

  6. Estimating the Pollution Risk of Cadmium in Soil Using a Composite Soil Environmental Quality Standard

    PubMed Central

    Huang, Biao; Zhao, Yongcun

    2014-01-01

    Estimating standard-exceeding probabilities of toxic metals in soil is crucial for environmental evaluation. Because soil pH and land use types have strong effects on the bioavailability of trace metals in soil, they were taken into account by some environmental protection agencies in making composite soil environmental quality standards (SEQSs) that contain multiple metal thresholds under different pH and land use conditions. This study proposed a method for estimating the standard-exceeding probability map of soil cadmium using a composite SEQS. The spatial variability and uncertainty of soil pH and site-specific land use type were incorporated through simulated realizations by sequential Gaussian simulation. A case study was conducted using a sample data set from a 150 km2 area in Wuhan City and the composite SEQS for cadmium, recently set by the State Environmental Protection Administration of China. The method may be useful for evaluating the pollution risks of trace metals in soil with composite SEQSs. PMID:24672364

  7. Ecotoxicological risk assessment of trace metals in humid subtropical soil.

    PubMed

    Adhikari, Gopi; Bhattacharyya, Krishna G

    2015-11-01

    In this work, several physicochemical properties of sub-tropical soil (up to 20 cm depth) like water holding capacity, organic carbon content, cation exchange capacity, texture, pH, and electrical conductivity were determined along with the trace metals, Co, Cr, Cu, Mn, Ni, Pb and Zn, in order to evaluate inter-relations among the trace metals and the soil properties. The contribution of the trace metals to ecotoxicological risk was assessed using various tools. Cr, Cu, Mn and Zn contents were found to be lower than the world average, but Co, Ni, and Pb had higher contents. The trace metal concentrations were utilized to obtain the pollution index and the potential ecotoxicological aspects. The trace metals were shown to have come from similar origin and their retention in the soil was contributed by properties like organic carbon, cation exchange capacity, clay content and water holding capacity of the soil. The pollution index showed that the trace metals had the sequence of Pb (considerably polluted) > Co, Ni (moderately polluted) > Cr, Cu, Mn and Zn (unpolluted). The composite ecological risk index was the highest in agricultural land with irrigation and fertilizer use, and was the lowest in the forest land. PMID:26254205

  8. A new model for polluted soil risk assessment

    NASA Astrophysics Data System (ADS)

    Andretta, M.; Serra, R.; Villani, M.

    2006-08-01

    In this paper, we discuss the most important theoretical aspects of polluted soil Risk Assessment Methodologies, which have been developed in order to evaluate the risk, for the exposed people, connected with the residual contaminant concentration in polluted soil, and we make a short presentation of the major different kinds of risk assessment methodologies. We also underline the relevant role played, in this kind of analysis, by the pollutant transport models. We also describe a new and innovative model, based on the general framework of the so-called Cellular Automata (CA), initially developed in the UE-Esprit Project COLOMBO for the simulation of bioremediation processes. These kinds of models, for their intrinsic "finite and discrete" characteristics, seem to be very well suited for a detailed analysis of the shape of the pollutant sources, the contaminant fates and the evaluation of target in the risk assessment evaluation. In particular, we will describe the future research activities we are going to develop in the area of a strict integration between pollutant fate and transport models and Risk Analysis Methodologies.

  9. Risk assessment of soils identified on firefighter turnout gear.

    PubMed

    Easter, Elizabeth; Lander, Deborah; Huston, Tabitha

    2016-09-01

    The purpose of this research was to identify the composition of soils on firefighter turnout gear and to determine the dermal exposure risks associated with the soils. Nine used Nomex hoods from the Philadelphia fire department were analyzed for the presence of trace metals and seven sets of used turnout gear were analyzed for semi-volatile organics. Turnout gear samples were removed from areas of the gear known to have high levels of dermal absorption including the collar, armpit, wrist, and crotch areas, from either the outer shell or thermal liner layers. The following compounds were detected: polycyclic aromatic hydrocarbons (PAHs), phthalate plasticizers, and polybrominated diphenyl ether flame retardants (PBDEs). A screening risk assessment was conducted by converting the measured concentrations to an estimated dermally absorbed dose based on estimates for the permeation coefficient (Kp) and an assumed firefighting exposure scenario. Benzo(a) pyrene had the highest dermal exposure risk based on carcinogenic effects and PBDE-99 had the highest dermal exposure risk based on non-carcinogenic effects. For the metals, arsenic had the highest dermal exposure risk for the use hoods. PMID:27027971

  10. A new model for polluted soil risk assessment

    NASA Astrophysics Data System (ADS)

    Andretta, M.; Villani, M.; Serra, R.

    2003-04-01

    In the last years, the problem of the evaluation of the risk related to soil pollution has became more and more important, all over the world. The increasing number of polluted soils in all the industrialised counties has required the formalisation of well defined methodologies for defining the technical and economical limits of soil remediation. Mainly, these limits are defined in terms of general threshold values that, in some cases, can not be reached even with the so called Best Available Technology (B.A.T.) due for example to the characteristics of the pollutants or of the affected soil, or on the extremely high cost or duration of the remedial intervention. For these reasons, both in the North American Countries and in the European ones, many alternative methodologies based on systematic and scientifically well founded approaches have been developed, in order to determine the real effects of the pollution on the receptor targets. Typically, these methodologies are organised into different levels of detail, the so called "TIERS". Tier 1 is based on a conservative estimation of the risk for the targets, that comes from very general and "worst case" general situations. Tier 2 is based on a more detailed and site specific estimation of the hazard, evaluated by the use of semi-empirical, analytical formulas for the source characterisation, the transport of the pollutant, the target exposition evaluation. Tier 3 is the more detailed and site specific level of application of the risk assessment methodologies and requires the use of numerical methods with many detailed information on the site and on the receptors (e.g.: chemical/physical parameters of the pollutants, hydro-geological data, exposition data, etc.) In this paper, we describe the most important theoretical aspects of the polluted soil risk assessment methodologies and the relevant role played, in this kind of analysis, by the pollutant transport models. In particular, we describe a new and innovative

  11. Risk of antibiotic resistance from metal contaminated soils

    NASA Astrophysics Data System (ADS)

    Knapp, Charles

    2013-04-01

    It is known that contaminated soils can lead to increased incidence of illness and disease, but it may also prevent our ability to fight disease. Many antibiotic resistant genes (ARG) acquired by bacteria originate from the environment. It is important to understand factors that influence levels of ARG in the environment, which could affect us clinically and agriculturally. The presence of elevated metal content in soils often promotes antibiotic resistance in exposed microorganisms. Using qPCR, the abundances of ARG to compare levels with geochemical conditions in randomly selected soils from several countries. Many ARG positively correlated with soil metal content, especially copper, chromium, nickel, lead, and iron. Results suggest that geochemical metal conditions influence the potential for antibiotic resistance in soil, which might be used to estimate baseline gene presence on various landscape scales and may translate to epidemiological risk of antibiotic-resistance transmission from the environment. This suggests that we may have to reconsider tolerances of metal pollution in the environment.

  12. Assessing the pollution risk of soil Chromium based on loading capacity of paddy soil at a regional scale

    PubMed Central

    Qu, Mingkai; Li, Weidong; Zhang, Chuanrong; Huang, Biao; Zhao, Yongcun

    2015-01-01

    The accumulation of a trace metal in rice grain is not only affected by the total concentration of the soil trace metal, but also by crop variety and related soil properties, such as soil pH, soil organic matter (SOM) and so on. However, these factors were seldom considered in previous studies on mapping the pollution risk of trace metals in paddy soil at a regional scale. In this study, the spatial nonstationary relationships between rice-Cr and a set of perceived soil properties (soil-Cr, soil pH and SOM) were explored using geographically weighted regression; and the relationships were then used for calculating the critical threshold (CT) of soil-Cr concentration that may ensure the concentration of rice-Cr being below the permissible limit. The concept of “loading capacity” (LC) for Cr in paddy soil was then defined as the difference between the CT and the real concentration of Cr in paddy soil, so as to map the pollution risk of soil-Cr to rice grain and assess the risk areas in Jiaxing city, China. Compared with the information of the concentration of the total soil-Cr, such results are more valuable for spatial decision making in reducing the accumulation of rice-Cr at a regional scale. PMID:26675587

  13. Assessing the pollution risk of soil Chromium based on loading capacity of paddy soil at a regional scale

    NASA Astrophysics Data System (ADS)

    Qu, Mingkai; Li, Weidong; Zhang, Chuanrong; Huang, Biao; Zhao, Yongcun

    2015-12-01

    The accumulation of a trace metal in rice grain is not only affected by the total concentration of the soil trace metal, but also by crop variety and related soil properties, such as soil pH, soil organic matter (SOM) and so on. However, these factors were seldom considered in previous studies on mapping the pollution risk of trace metals in paddy soil at a regional scale. In this study, the spatial nonstationary relationships between rice-Cr and a set of perceived soil properties (soil-Cr, soil pH and SOM) were explored using geographically weighted regression; and the relationships were then used for calculating the critical threshold (CT) of soil-Cr concentration that may ensure the concentration of rice-Cr being below the permissible limit. The concept of “loading capacity” (LC) for Cr in paddy soil was then defined as the difference between the CT and the real concentration of Cr in paddy soil, so as to map the pollution risk of soil-Cr to rice grain and assess the risk areas in Jiaxing city, China. Compared with the information of the concentration of the total soil-Cr, such results are more valuable for spatial decision making in reducing the accumulation of rice-Cr at a regional scale.

  14. Percutaneous absorption of PCBs from soil: In vivo rhesus monkey, in vitro human skin, and binding to powdered human stratum corneum

    SciTech Connect

    Wester, R.C.; Maibach, H.I.; Sedik, L.; Melendres, J.; Wade, M. )

    1993-07-01

    Polychlorinated biphenyls (PCBs) are ubiquitous and persistent environmental pollutants. The major resident site for these PCBs is the soil, and human skin is frequently in contact with soil. Our objective was to determine the percutaneous absorption of the PCBs Aroclor 1242 and Aroclor 1254 from soil. PCB-contaminated soil was prepared at levels of 44 ppm Aroclor 1242 and 23 ppm Aroclor 1254. PCB concentrations on skin were 1.75 micrograms/cm2 for Aroclor 1242 and 0.91 microgram/cm2 for Aroclor 1254. In vivo percutaneous absorption in the rhesus monkey was determined by urinary and fecal [14C]-PCB excretion for a 5-wk period following topical dosing. Absorption of Aroclor 1242 was determined in vitro with human skin for comparative purposes. In vivo in the rhesus monkey the percutaneous absorption of Aroclor 1242 was 13.8 +/- 2.7 (SD)% of the dose and the absorption of Aroclor 1254 was 14.1 +/- 1.0%. These absorption amounts are similar to the absorption of Aroclor 1242 and 1254 from other vehicles (mineral oil, trichlorobenzene, acetone). With in vitro percutaneous absorption through human skin, most of the Aroclor 1242 and Aroclor 1254 resided in the skin and the amounts were dependent upon dosing vehicle (water > mineral oil > soil). Both PCBs readily partitioned from water into soil and human powdered stratum corneum. By difference the partitioning favored both PCBs going from soil into stratum corneum. These data emphasize the role of soil in percutaneous absorption and provide information for appropriate risk assessment.

  15. Assessing the bioavailability and risk from metal contaminated soils and dusts#

    EPA Science Inventory

    Exposure to contaminated soil and dust is an important pathway in human and ecological risk assessment and often is the "risk-driver" for metal contaminated soil. Site-specific soil physical and chemical characteristics, as well as biological factors, determine the bioavailabilit...

  16. IMPROVED RISK ASSESSMENT AND REMEDIATION OF SOIL METALS BASED ON BIOAVAILABILITY MEASUREMENTS

    EPA Science Inventory

    Heavy metals in soils can comprise risk through plant uptake or soil ingestion. Recent research results and progress in understandings of risks and methods for soil metal remediation will be presented. Beneficial use of composts/bosolids plus limestone to remediate metal killed e...

  17. Risk-based ecological soil quality criteria for the characterization of contaminated soils. Combination of chemical and biological tools.

    PubMed

    Fernández, María Dolores; Vega, María Milagrosa; Tarazona, José Vicente

    2006-08-01

    This paper describes the development of soil quality criteria for the characterization of soils focused on the potential risk to the ecosystem. The approach combines both Generic Soil Quality standards (GSQs) for individual chemicals and direct ecotoxicity assays on soil samples taken from the site. Criteria establish three main risk levels with their corresponding trigger values. The trigger values to determine high risk or "polluted" soils are exclusively based on direct toxicity assessments. The trigger values for the other categories are established by a combination of the application of GSQs and the results of bioassays. Low-risk is assumed when no toxicity is observed and GSQs based on precautionary ecotoxicity thresholds are not exceeded; high-risk must be considered if acute toxicity above the proposed trigger value is observed in soil or leachate samples. In between these levels, the risk cannot be elucidated and a site-specific assessment is required. The GSQs take into account the current or future land use, thus defining three categories: industrial soils, urban/residential soils and natural/agricultural/forest soils, each of them with different ecological requirements. The GSQ values are established following an inverse risk assessment methodology, integrating ecotoxicity and exposure models and setting the soil levels associated to pre-established criteria for the assumption of low risk. The proposed methodology covers all relevant ecological receptors and processes, soil organisms, potential contamination of ground and surface waters, and exposure of terrestrial vertebrates due to bioaccumulation and biomagnification. Exposure routes and protection criteria are defined in each protection goal. The relevance of each receptor and route is established according to the land use. PMID:16574196

  18. Consideration of soil properties in assessment of human health risk from exposure to arsenic-enriched soils.

    PubMed

    Datta, Rupali; Sarkar, Dibyendu

    2005-01-01

    Encroachment of residential development on agricultural lands in the United States where arsenical pesticides were extensively used prior to the 1990s has increased the potential for human exposure to arsenic (As), a group A carcinogen. Soil ingestion by children is a critical issue in assessing health risks from exposure to As-enriched soils. In the absence of a universal "soil model" on As bioavailability, many baseline risk assessment studies use the assumption that all (100%) As present in soil is bioavailable. However, As exists in many geochemical forms as dictated by soil chemical properties. Because As bioavailability is a function of soil speciation, using total soil arsenic values potentially overestimates human health risk, thereby increasing site cleanup expenses. A laboratory incubation study was conducted to estimate in vitro As bioavailability as a function of soil properties in four chemically variant soil types contaminated with sodium arsenite pesticide. Results demonstrate that As speciation in certain soils translates to significant lowering of As bioavailability and hence potential cancer risk. PMID:16637147

  19. Assessing the bioavailability and risk from metal-contaminated soils and dusts

    EPA Science Inventory

    Exposure to contaminated soil and dust is an important pathway in human health risk assessment. Physical and chemical characteristics, as well as biological factors, determine the bioaccessibility/bioavailability of soil and dust contaminants. Within a single sample, contaminat...

  20. Potential change in soil erosion trend and risk during 2010-2039 in central Oklahoma, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The potential for global climate changes to increase risk of soil erosion is clear, but quantitative analysis of this risk is limited due to high spatial and temporal variability in projected climate change scenarios. For accurate prediction of soil erosion risk under climate change, climate chang...

  1. The occurrence, sources and spatial characteristics of soil salt and assessment of soil salinization risk in Yanqi basin, northwest China.

    PubMed

    Zhaoyong, Zhang; Abuduwaili, Jilili; Yimit, Hamid

    2014-01-01

    In order to evaluate the soil salinization risk of the oases in arid land of northwest China, we chose a typical oasis-the Yanqi basin as the research area. Then, we collected soil samples from the area and made comprehensive assessment for soil salinization risk in this area. The result showed that: (1) In all soil samples, high variation was found for the amount of Ca2+ and K+, while the other soil salt properties had moderate levels of variation. (2) The land use types and the soil parent material had a significant influence on the amount of salt ions within the soil. (3) Principle component (PC) analysis determined that all the salt ion values, potential of hydrogen (pHs) and ECs fell into four PCs. Among them, PC1 (C1-, Na+, SO4(2-), EC, and pH) and PC2 (Ca2+, K+, Mg2+and total amount of salts) are considered to be mainly influenced by artificial sources, while PC3 and PC4 (CO3(-) and HCO3(2-)) are mainly influenced by natural sources. (4) From a geo-statistical point of view, it was ascertained that the pH and soil salt ions, such as Ca2+, Mg2+ and HCO3(-), had a strong spatial dependency. Meanwhile, Na+ and Cl- had only a weak spatial dependency in the soil. (5) Soil salinization indicators suggested that the entire area had a low risk of soil salinization, where the risk was mainly due to anthropogenic activities and climate variation. This study can be considered an early warning of soil salinization and alkalization in the Yanqi basin. It can also provide a reference for environmental protection policies and rational utilization of land resources in the arid region of Xinjiang, northwest China, as well as for other oases of arid regions in the world. PMID:25211240

  2. The Occurrence, Sources and Spatial Characteristics of Soil Salt and Assessment of Soil Salinization Risk in Yanqi Basin, Northwest China

    PubMed Central

    Zhaoyong, Zhang; Abuduwaili, Jilili; Yimit, Hamid

    2014-01-01

    In order to evaluate the soil salinization risk of the oases in arid land of northwest China, we chose a typical oasis-the Yanqi basin as the research area. Then, we collected soil samples from the area and made comprehensive assessment for soil salinization risk in this area. The result showed that: (1) In all soil samples, high variation was found for the amount of Ca2+ and K+, while the other soil salt properties had moderate levels of variation. (2) The land use types and the soil parent material had a significant influence on the amount of salt ions within the soil. (3) Principle component (PC) analysis determined that all the salt ion values, potential of hydrogen (pHs) and ECs fell into four PCs. Among them, PC1 (C1-, Na+, SO42-, EC, and pH) and PC2 (Ca2+, K+, Mg2+and total amount of salts) are considered to be mainly influenced by artificial sources, while PC3 and PC4 (CO3- and HCO32-) are mainly influenced by natural sources. (4) From a geo-statistical point of view, it was ascertained that the pH and soil salt ions, such as Ca2+, Mg2+ and HCO3-, had a strong spatial dependency. Meanwhile, Na+ and Cl- had only a weak spatial dependency in the soil. (5) Soil salinization indicators suggested that the entire area had a low risk of soil salinization, where the risk was mainly due to anthropogenic activities and climate variation. This study can be considered an early warning of soil salinization and alkalization in the Yanqi basin. It can also provide a reference for environmental protection policies and rational utilization of land resources in the arid region of Xinjiang, northwest China, as well as for other oases of arid regions in the world. PMID:25211240

  3. Characterization and solubility measurements of uranium-contaminated soils to support risk assessment

    SciTech Connect

    Elless, M.P.; Armstrong, A.Q.; Lee, S.Y.

    1997-05-01

    Remediation of uranium-contaminated soils is considered a high priority by the US Department of Energy because these soils, if left untreated, represent a hazard to the environment and human health. Because the risk to human health is a function of the solubility of uranium in the soils, the objectives of this work are to measure the uranium solubility of two contaminated soils, before and after remedial treatment, and determine the health risk associated with these soils. Two carbonate-rich, uranium-contaminated soils from the US Department of Energy Fernald Environmental Management Project facility near Cincinnati, Ohio, as well as two nearby background soils were characterized and their uranium solubility measured in a 75-d solubility experiment using acid rain, groundwater, lung serum, and stomach acid simulants. Results show that the soluble uranium levels of each soil by each simulant are greatly influenced by their contamination source term. Risk calculations and biokinetic modeling based on the solubility data show that the risks from the soil ingestion and groundwater ingestion pathways are the predominant contributors to the total carcinogenic risk, whereas the risk from the soil inhalation pathway is the smallest contributor to this risk. However, kidney toxicity was the greater health concern of the Fernald Environmental Management Project soils, primarily from undiluted ingestion of the groundwater solution following contact with the contaminated soils. Sensitivity analyses indicate that uranium solubility is a key parameter in defining kidney toxicity; therefore, without proper consideration of the solubility of radionuclides/metals in untreated and treated soils, important factors may be overlooked which may result in soil cleanup goals or limits which are not protective of human health and the environment.

  4. Soil Survey Grain Productivity and Productivity Risk Assessment with Yield Map Data

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yield monitors and computational tools have improved our capability to assess the impact of soil-landscape and climate variability on grain yield and yield risk. The objective of our study is to generate productivity information for use in soil survey applications and to calibrate a soil productivit...

  5. Organic amendments for risk mitigation of organochlorine pesticide residues in old orchard soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Performance of compost and biochar amendments for in situ risk mitigation of aged DDT, DDE and dieldrin residues in an old orchard soil was examined. The change in bioavailability of pesticide residues relative to an unamended control soil was assessed using Lumbricus terrestris in 4-L soil microcos...

  6. SOIL AND NUTRIENT EROSION RISK IN ORGANIC AND CONVENTIONAL CROPPING SYSTEMS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Organic farming, which is growing in popularity, has been proposed as a sustainable alternative to conventional farming practices. However, it is not known how organic farming systems affect soil erosion risk and sediment-bound nutrient transport. Our objectives were to compare soil erosion risk and...

  7. PROVIDING SOLUTIONS FOR A BETTER TOMORROW: REDUCING THE RISKS ASSOCIATED WITH LEAD IN SOIL; URL:

    EPA Science Inventory

    This brief publication describes, in general language, the health risks associated with exposure to soil and dust contaminated with lead as well as an innovative method to immobilize lead contaminants in the soil (and thereby reduce the risk of exposure) at Superfund sites. Also ...

  8. Toxicity and bioaccumulation of soil PCBs in crickets: Comparison of laboratory and field studies

    SciTech Connect

    Paine, J.M.; McKee, M.J.; Ryan, M.E. . Cooperative Wildlife Research Lab. and Dept. of Zoology)

    1993-11-01

    Laboratory and field studies were used to investigate toxicity and bioaccumulation of PCBs in crickets exposed to contaminated soil. A 14-d laboratory soil bioassay with the house cricket (Acheta domesticus) yielded an LC50 of 1,200 ppm Aroclor 1254. Mean whole-body concentrations of Aroclor 1254 in exposed crickets were 11, 48, 92, 149, and 144 ppm for soil test concentrations of 100, 250, 500, 1,000, and 2,000 ppm, respectively. A whole-body concentration of about 150 ppm appears to be a threshold concentration above which acute mortality will be observed. House crickets placed in cages on a PCB-contaminated landfill accumulated 1.6 and 0.9 ppm of PCBs after 3 and 7 d of exposure, respectively. Although this represents a rapid uptake of PCBs, whole-body concentrations remained considerably below levels expected to cause acute mortality. Abundance of another species, the field cricket (Gryllus pennsylvanicus), was investigated using pitfall traps placed at the PCB-contaminated landfill and a reference site. No adverse effect on abundance was observed at the contaminated site, nor was pitfall trap success correlated to soil PCB concentration. These data indicate that PCBs in soil can rapidly move into epigeic fauna but that the likelihood of acquiring sufficient body burdens to cause acute mortality is low.

  9. Metals in residential soils and cumulative risk assessment in Yaqui and Mayo agricultural valleys, northern Mexico.

    PubMed

    Meza-Montenegro, Maria M; Gandolfi, A Jay; Santana-Alcántar, María Ernestina; Klimecki, Walter T; Aguilar-Apodaca, María Guadalupe; Del Río-Salas, Rafael; De la O-Villanueva, Margarita; Gómez-Alvarez, Agustín; Mendivil-Quijada, Héctor; Valencia, Martín; Meza-Figueroa, Diana

    2012-09-01

    This investigation examines the extent of soil metal pollution associated with the Green Revolution, relative to agricultural activities and associated risks to health in the most important agricultural region of Mexico. Metal contents in bulk soil samples are commonly used to assess contamination, and metal accumulations in soils are usually assumed to increase with decreasing particle size. This study profiled the spatial distribution of metals (Ni, Cr, Pb, Cu, Fe, Cd, V, Hg, Co, P, Se, and Mn) in bulk soil and fine-grained fractions (soil-derived dust) from 22 towns and cities. The contamination of soil was assessed through the use of a geoaccumulation index (Igeo) and pollution index (PI). The results of this study indicated that a number of towns and cities are moderately to highly polluted by soil containing Be, Co, Hg, P, S, V, Zn, Se, Cr, and Pb in both size fractions (coarse and fine). Hazard index in fine fraction (HI(children)=2.1) shows that risk assessment based on Co, Mn, V, and Ni spatially related to power plants, have the potential to pose health risks to local residents, especially children. This study shows that risk assessment based on metal content in bulk soil could be overestimated when compared to fine-grained fraction. Our results provide important information that could be valuable in establishing risk assessment associated with residential soils within agricultural areas, where children can ingest and inhale dust. PMID:22820616

  10. Spatial pattern of heavy metals accumulation risk in urban soils of Beijing and its influencing factors.

    PubMed

    Liu, Rui; Wang, Meie; Chen, Weiping; Peng, Chi

    2016-03-01

    Accumulations of heavy metals in urban soils are highly spatial heterogeneity and affected by multiple factors including soil properties, land use and pattern, population and climatic conditions. We studied accumulation risks of Cd, Cu, Pb and Zn in unban soils of Beijing and their influencing based on the regression tree analysis and a GIS-based overlay model. Result shows that Zinc causes the most extensive soil pollution and Cu result in the most acute soil pollution. The soil's organic carbon content and CEC and population growth are the most significant factors affecting heavy metal accumulation. Other influence factors in land use pattern, urban landscape, and wind speed also contributed, but less pronounced. The soils in areas with higher degree of urbanization and surrounded by intense vehicular traffics have higher accumulation risk of Cd, Cu, Pb, and Zn. PMID:26716731

  11. Improvement of erosion risk modelling using soil information derived from aerial Vis-NIR imagery

    NASA Astrophysics Data System (ADS)

    Ciampalini, Rossano; Raclot, Damien; Le Bissonnais, Yves

    2016-04-01

    The aim of this research is to test the benefit of the hyperspectral imagery in soil surface properties characterisation for soil erosion modelling purposes. The research area is the Lebna catchment located in the in the north of Tunisia (Cap Bon Region). Soil erosion is evaluated with the use of two different soil erosion models: PESERA (Pan-European Soil Erosion Risk Assessment already used for the soil erosion risk mapping for the European Union, Kirkby et al., 2008) and Mesales (Regional Modelling of Soil Erosion Risk developed by Le Bissonnais et al., 1998, 2002); for that, different sources for soil properties and derived parameters such as soil erodibility map and soil crusting map have been evaluated with use of four different supports: 1) IAO soil map (IAO, 2000), 2) Carte Agricole - CA - (Ministry of Agriculture, Tunisia), 3) Hyperspectral VIS-NIR map - HY - (Gomez et al., 2012; Ciampalini t al., 2012), and, 3) a here developed Hybrid map - CY - integrating information from Hyperspectral VIS-NIR and pedological maps. Results show that the data source has a high influence on the estimation of the parameters for both the models with a more evident sensitivity for Pesera. With regard to the classical pedological data, the VIS-NIR data clearly ameliorates the spatialization of the texture, then, the spatial detail of the results. Differences in the output using different maps are more important in Pesera model than in Mesales showing no-change ranges of about 15 to 41% and 53 to 67%, respectively.

  12. Accumulation and risks of polycyclic aromatic hydrocarbons and trace metals in tropical urban soils.

    PubMed

    Khillare, P S; Hasan, Amreen; Sarkar, Sayantan

    2014-05-01

    The study deals with the combined contribution of polycyclic aromatic hydrocarbons (PAHs) and metals to health risk in Delhi soils. Surface soils (0-5 cm) collected from three different land-use regions (industrial, flood-plain and a reference site) in Delhi, India over a period of 1 year were characterized with respect to 16 US Environmental Protection Agency priority PAHs and five trace metals (Zn, Fe, Ni, Cr and Cd). Mean annual ∑16PAH concentrations at the industrial and flood-plain sites (10,893.2 ± 2826.4 and 3075.4 ± 948.7 μg/kg, respectively) were ~15 and ~4 times, respectively, higher than reference levels. Significant spatial and seasonal variations were observed for PAHs. Toxicity potentials of industrial and flood-plain soils were ~88 and ~8 times higher than reference levels. Trace metal concentrations in soils also showed marked dependencies on nearness to sources and seasonal effects. Correlation analysis, PAH diagnostic ratios and principal component analysis (PCA) led to the identification of sources such as coal and wood combustion, vehicular and industrial emissions, and atmospheric transport. Metal enrichment in soil and the degree of soil contamination were investigated using enrichment factors and index of geoaccumulation, respectively. Health risk assessment (incremental lifetime cancer risk and hazard index) showed that floodplain soils have potential high risk due to PAHs while industrial soils have potential risks due to both PAHs and Cr. PMID:24374784

  13. Method for Assessing the Integrated Risk of Soil Pollution in Industrial and Mining Gathering Areas

    PubMed Central

    Guan, Yang; Shao, Chaofeng; Gu, Qingbao; Ju, Meiting; Zhang, Qian

    2015-01-01

    Industrial and mining activities are recognized as major sources of soil pollution. This study proposes an index system for evaluating the inherent risk level of polluting factories and introduces an integrated risk assessment method based on human health risk. As a case study, the health risk, polluting factories and integrated risks were analyzed in a typical industrial and mining gathering area in China, namely, Binhai New Area. The spatial distribution of the risk level was determined using a Geographic Information System. The results confirmed the following: (1) Human health risk in the study area is moderate to extreme, with heavy metals posing the greatest threat; (2) Polluting factories pose a moderate to extreme inherent risk in the study area. Such factories are concentrated in industrial and urban areas, but are irregularly distributed and also occupy agricultural land, showing a lack of proper planning and management; (3) The integrated risks of soil are moderate to high in the study area. PMID:26580644

  14. Method for Assessing the Integrated Risk of Soil Pollution in Industrial and Mining Gathering Areas.

    PubMed

    Guan, Yang; Shao, Chaofeng; Gu, Qingbao; Ju, Meiting; Zhang, Qian

    2015-11-01

    Industrial and mining activities are recognized as major sources of soil pollution. This study proposes an index system for evaluating the inherent risk level of polluting factories and introduces an integrated risk assessment method based on human health risk. As a case study, the health risk, polluting factories and integrated risks were analyzed in a typical industrial and mining gathering area in China, namely, Binhai New Area. The spatial distribution of the risk level was determined using a Geographic Information System. The results confirmed the following: (1) Human health risk in the study area is moderate to extreme, with heavy metals posing the greatest threat; (2) Polluting factories pose a moderate to extreme inherent risk in the study area. Such factories are concentrated in industrial and urban areas, but are irregularly distributed and also occupy agricultural land, showing a lack of proper planning and management; (3) The integrated risks of soil are moderate to high in the study area. PMID:26580644

  15. Ecological Risk of Heavy Metals and a Metalloid in Agricultural Soils in Tarkwa, Ghana

    PubMed Central

    Bortey-Sam, Nesta; Nakayama, Shouta M. M.; Akoto, Osei; Ikenaka, Yoshinori; Baidoo, Elvis; Mizukawa, Hazuki; Ishizuka, Mayumi

    2015-01-01

    Heavy metals and a metalloid in agricultural soils in 19 communities in Tarkwa were analyzed to assess the potential ecological risk. A total of 147 soil samples were collected in June, 2012 and analyzed for As, Cd, Co, Cr, Cu, Hg, Ni, Pb and Zn. Mean concentrations (mg/kg dw) of heavy metals in the communities decreased in order of Zn (39) ˃ Cr (21) ˃ Pb (7.2) ˃ Cu (6.2) ˃ As (4.4) ˃ Ni (3.7) ˃ Co (1.8) ˃ Hg (0.32) ˃ Cd (0.050). Correlations among heavy metals and soil properties indicated that soil organic matter could have substantial influence on the total contents of these metals in soil. From the results, integrated pollution (Cdeg) in some communities such as, Wangarakrom (11), Badukrom (13) and T–Tamso (17) indicated high pollution with toxic metals, especially from As and Hg. Potential ecological risk (RI) indices indicated low (Mile 7) to high risks (Wangarakrom; Badukrom) of metals. Based on pollution coefficient (Cif), Cdeg, monomial ecological risk (Eir) and RI, the investigated soils fall within low to high contamination and risk of heavy metals to the ecological system especially plants, soil invertebrates and/or mammalian wildlife. This represented moderate potential ecological risk in the study area, and mining activities have played a significant role. PMID:26378563

  16. Assessment of arsenic (As) occurrence in arable soil and its related health risk in China.

    PubMed

    Zhang, Xiuying; Zhong, Taiyang; Chen, Dongmei; Cheng, Min; Liu, Lei; Zhang, Xiaomin; Li, Xinhui

    2016-06-01

    Arsenic (As) is a major global environmental pollutant due to its high toxicity on human and animal health. This study collected 427 relevant papers to study As concentrations in Chinese arable soil and evaluate the health risk of exposure to As for humans. Results showed that the average of As concentration was 9.46 mg/kg in Chinese arable soil. Soil As concentrations in Hunan Province and Guangxi Zhuang Autonomous Region posed high carcinogenic and non-cancer risks on human health through diet, Yunnan, Guizhou, Guangdong, and Xinjiang provinces had relative high health risks, while As concentrations in the other provinces posed low health risks on humans. The physical factors controlled the spatial pattern of health risk on a provincial scale, but the As-related human activities introduced high health risk on people, particularly the agricultural activities such as sewage irrigation and fertilizer application should be given more attention due to its large area. PMID:26209282

  17. Risk perception of heavy metal soil contamination and attitudes toward decontamination strategies.

    PubMed

    Weber, O; Scholz, R W; Bühlmann, R; Grasmück, D

    2001-10-01

    Contaminated soils are a common environmental risk all over the world. One major source of risk is heavy metal soil contamination caused by industrial emissions. This quasiexperimental study investigated the perception of these risks by exposed and nonexposed people, their attitudes toward bioremediation methods using hyperaccumulating plants, and the influence of long-term aspects of sustainability on the acceptance of bioremediation methods. Major findings were that people living in a contaminated area perceived the risk of the heavy metal soil contamination as higher than the general risk of contamination. Second, a factor analysis showed that the factors dread, control, and catastrophic potential were relevant for the perception and valuation of low-dose environmental risks such as the contamination of the investigated area. In addition, a cluster analysis showed that the risk of heavy metal soil contamination was perceived as similar to that of oil contamination, ozone layer, preservatives and genetic technology. It was perceived indifferently with regard to dread. The uncontrollability of heavy metal soil contamination was estimated as medium, and its catastrophic potential as low. Third, exposed and nonexposed participants preferred bioremediation methods to classical methods (e.g., excavation and chemical treatment of the soil), because they perceived the environmental and esthetical performance of the bioremediation as important criteria. Sustainability or precautionary issues, such as the prevention of harm for future generations, were highly correlated with the acceptance of the use of bioremediation methods in people's residential areas. PMID:11798130

  18. Children's exposure to mercury-contaminated soils: exposure assessment and risk characterization.

    PubMed

    Guney, Mert; Welfringer, Bruno; de Repentigny, Carl; Zagury, Gerald J

    2013-08-01

    Exposure to mercury (Hg)-contaminated soils may pose a health risk to children by way of oral, dermal, and inhalatory pathways. However, risk characterization studies, including contaminant bioaccessibility with child-specific exposure parameters and scenarios, are lacking. The objectives of this study were (1) to assess children's Hg exposure using characterization and oral bioaccessibility data from Hg-contaminated soils characterized in previous studies (n = 8); and (2) to characterize probabilistic risk in terms of hazard index (HI) considering ingestion, dermal, and inhalation pathways. Total Hg concentrations in soils ranged from 2.61 to 1.15 × 10(4) mg kg(-1). For moderately contaminated soils (S1-S5: Hg ≤ 12.15 mg kg(-1)), low oral bioaccessibility values (1.5-7.5 %) lead to HI < 1 in all scenarios. However, exposure to highly contaminated soils (S6-S8) may pose serious risks to children under normal exposure (HI 0.89-66.5) and soil-pica behaviour scenarios (HI up to 131). All three pathways significantly contributed to the risk. Using total Hg concentrations in calculations (assuming 100 % bioavailability) instead of considering Hg bioavailability leads to risk overestimation. Further research on oral, inhalatory, and dermal bioavailability of Hg, as well as child play behaviour, is recommended to obtain more accurate risk estimates. PMID:23546335

  19. An empirical approach to estimate soil erosion risk in Spain.

    PubMed

    Martín-Fernández, Luis; Martínez-Núñez, Margarita

    2011-08-01

    Soil erosion is one of the most important factors in land degradation and influences desertification worldwide. In 2001, the Spanish Ministry of the Environment launched the 'National Inventory of Soil Erosion (INES) 2002-2012' to study the process of soil erosion in Spain. The aim of the current article is to assess the usefulness of this National Inventory as an instrument of control, measurement and monitoring of soil erosion in Spain. The methodology and main features of this National Inventory are described in detail. The results achieved as of the end of May 2010 are presented, together with an explanation of the utility of the Inventory as a tool for planning forest hydrologic restoration, soil protection, erosion control, and protection against desertification. Finally, the authors make a comparative analysis of similar initiatives for assessing soil erosion in other countries at the national and European levels. PMID:21621247

  20. A review of soil cadmium contamination in China including a health risk assessment.

    PubMed

    Wang, Lin; Cui, Xiangfen; Cheng, Hongguang; Chen, Fei; Wang, Jiantong; Zhao, Xinyi; Lin, Chunye; Pu, Xiao

    2015-11-01

    Cadmium (Cd) is one of the most serious soil contaminants in China, and it poses an increasing risk to human health as large amounts of Cd are emitted into the environment. However, knowledge about soil Cd concentrations and the human health risks of these concentrations at a national scale is limited. In this study, we conducted a review of 190 articles about soil Cd concentrations during 2001 to 2010. The study involved 146 cities in China, and we quantified the risks to human health according to different regions. The results showed that elevated Cd levels were present compared to the background value of soil in 1990, and the soil Cd concentrations in the Guangxi province exceeded even the class III Soil Environmental Quality standard, which is the limit for the normal growth of plants. The Chinese soil Cd concentrations ranged from 0.003 mg kg(-1) to 9.57 mg kg(-1). The soil Cd concentrations had the following trend: northwest > southwest > south central > east > northeast > north. The sources of soil Cd are mainly from smelting, mining, waste disposal, fertilizer and pesticide application, and vehicle exhaust, etc. but differentiated in various regions. The soil Cd contamination in urban areas was more serious than contamination in the agricultural areas. Currently, there is no significant non-carcinogenic risk in any of the provinces. Regarding the different exposure pathways, the dermal pathway is the primary source of soil Cd exposure, and the risk associated with this pathway is generally hundreds of times higher than the risk for an ingestion pathway. For most of the provinces, the health risk to the urban population was higher than the risk to the rural population. For each population, the carcinogenic risk was less than 10(-6) in most of the provinces, except for the urban population in the Hunan province. If the other exposure pathways are fully considered, then the people in these areas may have a higher carcinogenic risk. This

  1. Risk assessment applications for determining cleanup limits for uranium in treated and untreated soils

    SciTech Connect

    Armstrong, A.Q.; Layton, D.W.; Rutz, E.E.

    1994-06-01

    Uranium-contaminated soils are present at various locations across the US where uranium was processed for nuclear fuels or atomic weapons. Important issues relative to such contamination include the assessment of potential health risks associated with human exposures to the residual uranium and the determination of safe levels of uranium in soils that have been treated by a given technology. This paper discusses various risk assessment considerations that must be dealt with when developing cleanup limits for uranium in treated and untreated soils. Key issues addressed include alternative land use scenarios, potential exposure pathways, characterization of the bioavailability of uranium compounds in food and water, a brief overview of health risks associated with uranium and its daughter products as well as a summary of considerations for development of risk-based cleanup limits for uranium in soils.

  2. [Microbiologic/hygienic evaluation of the risk potential of bacteria from soil and water sources in combination with biotechnologic risks of soil restoration].

    PubMed

    Dott, W; Kämpfer, P

    1997-08-01

    Biological cleanup-processes removing contaminations from soil and ground-water can be carried out "ex-situ" or "in situ". The pollutants are mineralized (totally or partly) by microorganisms. The successful application of bioremediation techniques often leads to an increase of aerobic and facultatively anaerobic bacteria in soil and/or groundwater, a fact that triggered discussions about a potential biological risk originating from these microorganisms. In this study the identification results of 10,200 microorganisms isolated from 109 ground-water- and 152 soil-samples of different sites contaminated with mineral oil or chlorinated aromatics are evaluated with respect to a possible biological risks originating from these microorganisms. According to their biological risk potential, 19.2% (1958) of the isolated organisms can be grouped into risk-groups II, that means they they are able o cause human disease but it is unlikely that they are spread to the community and there is effective prophylaxis or treatment available. The majority of isolates (81.8%) are grouped into risk group I, meaning that it is very unlikely that they cause a human disease. All these microorganisms are either adsorbed to the soil-matrix or within a closed system of a water-treatment-plant, so that the risk of infection is very unlikely for healthy individuals (regarding possible pathways of infection). The risk potential in waste-water-treatment-plants is regarded to be significantly higher than in biological soil-cleanup processes, because of the specific origin of the bacteria and the possible formation of aerosols. PMID:9636987

  3. A framework for risk assessment on soil erosion by water using an integrated and systematic approach

    NASA Astrophysics Data System (ADS)

    Wu, Qiang; Wang, Mingyu

    2007-04-01

    SummaryA new approach for establishment of an analytical risk assessment model to evaluate the risk index for soil erosion by water is proposed, in which the remote sensing, GIS, the analytical hierarchy process (AHP), and modeling techniques are integrated through investigation of soil erosion by water in a joining area that partially covers the Shanxi province, Shaanxi province, and Inner Mongolia Autonomous Region of China. Based on field survey and information analyses, pertinent factors for soil erosion by water in this region are assessed and nine dominating factors are identified. The considered dominating factors include the soil type, rainstorm intensity, landform accounting for physiognomy type, ravine density, and land slope, vegetation coverage, mining area, level of water and soil conservation, and type of land uses. The GIS thematic layers of degrees of risk on soil erosion for those dominating factors are constructed. The weight of each thematic layer is determined through the AHP technique. This model is then applied in predicting development of soil erosion at a typical scenario for this study area. A brief discussion on construction and application of this model is presented. It is demonstrated that the presented methodology is practicable for establishing a risk assessment mode for soil erosion by water for an area of interest where pertinent information such as remote sensing data is available. A flowchart presenting a general procedure for implementation of the proposed approach is also included.

  4. Sorption indices to estimate risk of soil phosphorus loss in the Rathbun Lake Watershed, Iowa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To rank and better understand the risk of P loss from potentially erodible soil materials in the Mollisol-dominated watershed of Rathbun Lake in southern Iowa, we sampled seven representative soil materials at four floodplain sites. We compared the samples by using a variety of characteristics and i...

  5. Assessing soil erosion risk using RUSLE through a GIS open source desktop and web application.

    PubMed

    Duarte, L; Teodoro, A C; Gonçalves, J A; Soares, D; Cunha, M

    2016-06-01

    Soil erosion is a serious environmental problem. An estimation of the expected soil loss by water-caused erosion can be calculated considering the Revised Universal Soil Loss Equation (RUSLE). Geographical Information Systems (GIS) provide different tools to create categorical maps of soil erosion risk which help to study the risk assessment of soil loss. The objective of this study was to develop a GIS open source application (in QGIS), using the RUSLE methodology for estimating erosion rate at the watershed scale (desktop application) and provide the same application via web access (web application). The applications developed allow one to generate all the maps necessary to evaluate the soil erosion risk. Several libraries and algorithms from SEXTANTE were used to develop these applications. These applications were tested in Montalegre municipality (Portugal). The maps involved in RUSLE method-soil erosivity factor, soil erodibility factor, topographic factor, cover management factor, and support practices-were created. The estimated mean value of the soil loss obtained was 220 ton km(-2) year(-1) ranged from 0.27 to 1283 ton km(-2) year(-1). The results indicated that most of the study area (80 %) is characterized by very low soil erosion level (<321 ton km(-2) year(-1)) and in 4 % of the studied area the soil erosion was higher than 962 ton km(-2) year(-1). It was also concluded that areas with high slope values and bare soil are related with high level of erosion and the higher the P and C values, the higher the soil erosion percentage. The RUSLE web and the desktop application are freely available. PMID:27184749

  6. Identification of vulnerable areas to soil erosion risk in India using GIS methods

    NASA Astrophysics Data System (ADS)

    Biswas, H.; Raizada, A.; Mandal, D.; Kumar, S.; Srinivas, S.; Mishra, P. K.

    2015-06-01

    This paper attempts to provide information for policy makers and soil conservation planners in the form of district-wise soil erosion risk (SER) maps prepared for the state of Telengana, India. The SER values for each district were computed by extracting the information on grid-wise soil erosion and soil loss tolerance limit values existing on the country-scale in a GIS environment. The objectives of the study were to (i) identify the areas of the state with high erosion risk, and (ii) identify areas with urgent needs of conservation measures. The results reveal that around 69% of the state has negligible risk of soil erosion above the tolerance limits, and does not call for immediate soil conservation measures. The remaining area (2.17M ha) requires conservation planning. Four districts, viz. Adilabad, Warangal, Khammam and Karimnagar are the most risk prone with more than one-fourth of their total geographical areas showing net positive SER values. In order to obtain a clearer picture and categorize the districts based on their extent of vulnerability, the Weighted Erosion Risk values were computed. Adilabad, Warangal and Khammam were identified as the worst-affected districts in terms of soil erosion and therefore need immediate attention for natural resource conservation.

  7. Identification of areas vulnerable to soil erosion risk in India using GIS methods

    NASA Astrophysics Data System (ADS)

    Biswas, H.; Raizada, A.; Mandal, D.; Kumar, S.; Srinivas, S.; Mishra, P. K.

    2015-11-01

    This paper attempts to provide information for policymakers and soil conservation planners in the form of district-wise soil erosion risk (SER) maps prepared for the state of Telangana, India. The SER values for each district were computed by extracting the information on grid-wise soil erosion and soil loss tolerance limit values existing on the country-scale in a GIS environment. The objectives of the study were to (i) identify the areas of the state with a high erosion risk, and (ii) identify areas with an urgent need of conservation measures. The results reveal that around 69 % of the state has a negligible risk of soil erosion above the tolerance limits, and does not call for immediate soil conservation measures. The remaining area (2.17 M ha) requires conservation planning. Four districts, viz. Adilabad, Warangal, Khammam, and Karimnagar are the most risk-prone with more than one-quarter of their total geographical areas showing net positive SER values. In order to obtain a clearer picture and categorize the districts based on their extent of vulnerability, weighted erosion risk values were computed. Adilabad, Warangal, and Khammam were identified as the worst-affected districts in terms of soil erosion, and therefore are in need of immediate attention of natural resource conservation.

  8. The risk implications of approaches to setting soil remediation goals at hazardous waste contaminated sites

    SciTech Connect

    Labieniec, P.A.

    1994-08-01

    An integrated exposure and carcinogenic risk assessment model for organic contamination in soil, SoilRisk, was developed and used for evaluating the risk implications of both site-specific and uniform-concentration approaches to setting soil remediation goals at hazardous-waste-contaminated sites. SoilRisk was applied to evaluate the uncertainty in the risk estimate due to uncertainty in site conditions at a representative site. It was also used to evaluate the variability in risk across a region of sites that can occur due to differences in site characteristics that affect contaminant transport and fate when a uniform concentration approach is used. In evaluating regional variability, Ross County, Ohio and the State of Ohio were used as examples. All analyses performed considered four contaminants (benzene, trichloroethylene (TCE), chlordane, and benzo[a]pyrene (BAP)) and four exposure scenarios (commercial, recreational and on- and offsite residential). Regardless of whether uncertainty in risk at a single site or variability in risk across sites was evaluated, the exposure scenario specified and the properties of the target contaminant had more influence than variance in site parameters on the resulting variance and magnitude of the risk estimate. In general, variance in risk was found to be greater for the relatively less degradable and more mobile of the chemicals studied (TCE and chlordane) than for benzene which is highly degradable and BAP which is very immobile in the subsurface.

  9. Toxicity assessment through multiple endpoint bioassays in soils posing environmental risk according to regulatory screening values.

    PubMed

    Rodriguez-Ruiz, A; Asensio, V; Zaldibar, B; Soto, M; Marigómez, I

    2014-01-01

    Toxicity profiles of two soils (a brownfield in Legazpi and an abandoned iron mine in Zugaztieta; Basque Country) contaminated with several metals (As, Zn, Pb and Cu in Legazpi; Zn, Pb, Cd and Cu in Zugaztieta) and petroleum hydrocarbons (in Legazpi) were determined using a multi-endpoint bioassay approach. Investigated soils exceeded screening values (SVs) of regulatory policies in force (Basque Country; Europe). Acute and chronic toxicity bioassays were conducted with a selected set of test species (Vibrio fischeri, Dictyostelium discoideum, Lactuca sativa, Raphanus sativus and Eisenia fetida) in combination with chemical analysis of soils and elutriates, as well as with bioaccumulation studies in earthworms. The sensitivity of the test species and the toxicity endpoints varied depending on the soil. It was concluded that whilst Zugaztieta soil showed very little or no toxicity, Legazpi soil was toxic according to almost all the toxicity tests (solid phase Microtox, D. discoideum inhibition of fruiting body formation and developmental cycle solid phase assays, lettuce seed germination and root elongation test, earthworm acute toxicity and reproduction tests, D. discoideum cell viability and replication elutriate assays). Thus, albeit both soils had similar SVs, their ecotoxicological risk, and therefore the need for intervening, was different for each soil as unveiled after toxicity profiling based on multiple endpoint bioassays. Such a toxicity profiling approach is suitable to be applied for scenario-targeted soil risk assessment in those cases where applicable national/regional soil legislation based on SVs demands further toxicity assessment. PMID:24819436

  10. Accumulation, Allocation, and Risk Assessment of Polycyclic Aromatic Hydrocarbons (PAHs) in Soil-Brassica chinensis System

    PubMed Central

    Zhang, Juan; Fan, Shukai; Du, Xiaoming; Yang, Juncheng; Wang, Wenyan; Hou, Hong

    2015-01-01

    Farmland soil and leafy vegetables accumulate more polycyclic aromatic hydrocarbons (PAHs) in suburban sites. In this study, 13 sampling areas were selected from vegetable fields in the outskirts of Xi’an, the largest city in northwestern China. The similarity of PAH composition in soil and vegetation was investigated through principal components analysis and redundancy analysis (RDA), rather than discrimination of PAH congeners from various sources. The toxic equivalent quantity of PAHs in soil ranged from 7 to 202 μg/kg d.w., with an average of 41 μg/kg d.w., which exceeded the agricultural/horticultural soil acceptance criteria for New Zealand. However, the cancer risk level posed by combined direct ingestion, dermal contact, inhalation of soil particles, and inhalation of surface soil vapor met the rigorous international criteria (1×10−6). The concentration of total PAHs was (1052±73) μg/kg d.w. in vegetation (mean±standard error). The cancer risks posed by ingestion of vegetation ranged from 2×10−5 to 2×10−4 with an average of 1.66×10−4, which was higher than international excess lifetime risk limits for carcinogens (1×10−4). The geochemical indices indicated that the PAHs in soil and vegetables were mainly from vehicle and crude oil combustion. Both the total PAHs in vegetation and bioconcentration factor for total PAHs (the ratio of total PAHs in vegetation to total PAHs in soil) increased with increasing pH as well as decreasing sand in soil. The total variation in distribution of PAHs in vegetation explained by those in soil reached 98% in RDA, which was statistically significant based on Monte Carlo permutation. Common pollution source and notable effects of soil contamination on vegetation would result in highly similar distribution of PAHs in soil and vegetation. PMID:25679782

  11. Pesticides in persimmons, jujubes and soil from China: Residue levels, risk assessment and relationship between fruits and soils.

    PubMed

    Liu, Yihua; Li, Shiliang; Ni, Zhanglin; Qu, Minghua; Zhong, Donglian; Ye, Caifen; Tang, Fubin

    2016-01-15

    Extreme and uncontrolled usage of pesticides produces a number of problems for vegetation and human health. In this study, the existence of organophosphates (OPs), organochlorines (OCs), pyrethroids (PYs) and fungicides (FUs) were investigated in persimmons/jujubes and their planted soils, which were collected from China. One OP (dimethoate), three OCs (DDT, quintozene and aldrin), six PYs (bifenthrin, fenpropathrin, cyhalothrin, cypermethrin, fenvalerate and deltamethrin) and two FUs (triadimefon and buprofezin) were found in 36.4% of persimmons and 70.8% of jujubes, with concentrations from 1.0 μg/kg to 2945.0 μg/kg. The most frequently detected pesticides in the two fruits were fenpropathrin in persimmons and cypermethrin in jujubes, with the detection frequencies of 30.0% and 22.7%, respectively. The residues of 4.5% (persimmon) and 25.0% (jujube) of samples were higher than the maximum residue limits (MRLs) of China. Compared with the fruits, more types of pesticides and higher residues were observed in their planted soils. The most frequently detected pesticides were HCH in persimmon soil and DDT in jujube soil, with the detection frequencies of 10.9% and 12.7%, respectively. For the tested samples, 39.1% of fruit samples and 63.0% of soil samples with multiple residues (containing more than two pesticides) were noted, even up to 8 residues in fruits and 14 residues in soils. Except for cyhalothrin, the other short-term risks for the tested pesticides in the fruits were below 10%, and the highest long-term risk was 14.13% for aldrin and dieldrin. There was no significant health risk for consumers via consumption of the two fruits. PMID:26544891

  12. Risk assessment of urban soils contamination: The particular case of polycyclic aromatic hydrocarbons.

    PubMed

    Cachada, A; da Silva, E Ferreira; Duarte, A C; Pereira, R

    2016-05-01

    The assessment of soil quality and characterization of potential risks to the environment and human health can be a very difficult task due to the heterogeneity and complexity of the matrix, the poor understanding about the fate of contaminants in the soil matrix, scarcity of toxicological/ecotoxicological data and variability of guidelines. In urban soils these difficulties are enhanced by the patchy nature of urban areas and the presence of complex mixtures of organic and inorganic contaminants resulting from diffuse pollution caused by urban activities (e.g. traffic, industrial activity, and burning of carbon sources for heating). Yet, several tools are available which may help to assess the risks of soil contamination in a simpler, cost effective and reliable way. Within these tools, a tiered risk assessment (RA) approach, first based on a chemical screening in combination with geostatistical tools, may be very useful in urban areas. However, there is still much to improve and a long way to go in order to obtain a reliable RA, especially in the case of hydrophobic organic compounds such as polycyclic aromatic hydrocarbons (PAHs). This paper aims at proposing a RA framework to assess the environmental and human health risks of PAHs present in urban soils, based on existing models. In addition, a review on ecotoxicological, toxicological, and exposure assessment data was made, as well as of the existing soil quality guidelines for PAHs that can be used in the RA process. PMID:26878639

  13. Leaching risk of N-nitrosodimethylamine (NDMA) in soil receiving reclaimed wastewater.

    PubMed

    Haruta, Shinsuke; Chen, Weiping; Gan, Jay; Simůnek, Jirka; Chang, Andrew C; Wu, Laosheng

    2008-03-01

    N-nitrosodimethylamine (NDMA) is a potential carcinogen frequently found in treated wastewater as a byproduct of chlorination. The potential for NDMA to contaminate the groundwater is a significant concern. A solute fate and transport model, Hydrus-1D, was used to evaluate the leaching potential of NDMA under different irrigation practices and soil properties. The results indicate that the risk of NDMA to reach the ground water is slim, when the reclaimed wastewater is applied under the customary conditions for landscape irrigation. The NDMA disappears in the reclaimed wastewater receiving soils rapidly through the microbial degradation and the volatilization processes. The factors that enhance the leaching risk are the soil hydraulic conductivity, the NDMA adsorption constants, and the irrigation intensity. When the hydraulic conductivity of soil is high, the NDMA adsorption constant of soil is low and/or the irrigation intensity is high, the NDMA leaching risk may dramatically increase. To reduce the NDMA leaching risk, it is imperative that the fields be irrigated at the proper volume and frequency and attention be paid to fields with soils having high-hydraulic conductivities and/or low-NDMA adsorption constants. PMID:18067959

  14. Soil Cd availability to Indian mustard and environmental risk following EDTA addition to Cd-contaminated soil.

    PubMed

    Jiang, X J; Luo, Y M; Zhao, Q G; Baker, A J M; Christie, P; Wong, M H

    2003-02-01

    A pot experiment was conducted to investigate the influence of EDTA on the extractability of Cd in the soil and uptake of Cd by Indian mustard (Brassica juncea). Twenty levels of soil Cd concentration ranging from 10 to 200 mg kg(-1) were produced by spiking aliquots of a clay loam paddy soil with Cd(NO3)2. One week before the plants were harvested EDTA was applied to pots in which the soil had been spiked with 20, 40, 60...200 mg Cd kg(-1). The EDTA was added at the rate calculated to complex with all of the Cd added at the 200 mg kg(-1) level. Control pots spiked with 10, 30, 50... 190 mg Cd kg(-1) received no EDTA. The plants were harvested after 42 days' growth. Soil water- and NH4NO3-extractable Cd fractions increased rapidly following EDTA application. Root Cd concentrations decreased after EDTA application, but shoot concentrations increased when the soil Cd levels were >130 mg kg(-1) and Cd toxicity symptoms were observed. The increases in soil solution Cd induced by EDTA did not increase plant total Cd uptake but appeared to stimulate the translocation of the metal from roots to shoots when the plants appeared to be under Cd toxicity stress. The results are discussed in relation to the possible mechanisms by which EDTA may change the solubility and bioavailability of Cd in the soil and the potential for plant uptake and environmental risk due to leaching losses to groundwater. PMID:12688496

  15. [Soil salinity in greenland irrigated with reclaimed water and risk assessment].

    PubMed

    Pan, Neng; Chen, Wei-Ping; Jiao, Wen-Tao; Zhao, Zhong-Ming; Hou, Zhen-An

    2012-12-01

    Compared to drinking water or groundwater, reclaimed water contains more salts. Therefore, the effects of application of reclaimed water on the soil salinity have received great attentions. To evaluate the potential risks posed by long-term reclaimed water irrigation, we collected surface soil samples from urban green lands and suburban farmlands of Beijing represented different irrigation durations. The electrical conductivity (EC) and sodium adsorption ratio (SAR) in soils were measured subsequently. Both EC1:5 and SAR1.5 from the green land and farmland soils irrigated with reclaimed water were significantly higher than those of control treatments (drinking water or groundwater irrigation). The EC1:5 values increased by 12.4% and 84.2% than control treatments in the greenland and farmland, respectively. The SAR1:5 values increased by 64.5% and 145.8% than control treatments, respectively. No significant differences of both EC1:5 and SAR1:5 were found between of 0-10 cm and 10-20 cm soil layer. A slight decrease of soil porosity was observed. The field investigation suggested there was a high potential of soil salinization under long-term reclaimed water irrigation. Proper management practices should be implemented to minimize the soil salinity accumulation risk when using reclaimed water for irrigation in Beijing. PMID:23379127

  16. Mapping regional soil water erosion risk in the Brittany-Loire basin for water management agency

    NASA Astrophysics Data System (ADS)

    Degan, Francesca; Cerdan, Olivier; Salvador-Blanes, Sébastien; Gautier, Jean-Noël

    2014-05-01

    Soil water erosion is one of the main degradation processes that affect soils through the removal of soil particles from the surface. The impacts for environment and agricultural areas are diverse, such as water pollution, crop yield depression, organic matter loss and reduction in water storage capacity. There is therefore a strong need to produce maps at the regional scale to help environmental policy makers and soil and water management bodies to mitigate the effect of water and soil pollution. Our approach aims to model and map soil erosion risk at regional scale (155 000 km²) and high spatial resolution (50 m) in the Brittany - Loire basin. The factors responsible for soil erosion are different according to the spatial and time scales considered. The regional scale entails challenges about homogeneous data sets availability, spatial resolution of results, various erosion processes and agricultural practices. We chose to improve the MESALES model (Le Bissonnais et al., 2002) to map soil erosion risk, because it was developed specifically for water erosion in agricultural fields in temperate areas. The MESALES model consists in a decision tree which gives for each combination of factors the corresponding class of soil erosion risk. Four factors that determine soil erosion risk are considered: soils, land cover, climate and topography. The first main improvement of the model consists in using newly available datasets that are more accurate than the initial ones. The datasets used cover all the study area homogeneously. Soil dataset has a 1/1 000 000 scale and attributes such as texture, soil type, rock fragment and parent material are used. The climate dataset has a spatial resolution of 8 km and a temporal resolution of mm/day for 12 years. Elevation dataset has a spatial resolution of 50 m. Three different land cover datasets are used where the finest spatial resolution is 50 m over three years. Using these datasets, four erosion factors are characterized and

  17. Risk of classic Kaposi sarcoma with residential exposure to volcanic and related soils in Sicily

    PubMed Central

    Pelser, Colleen; Dazzi, Carmelo; Graubard, Barry I.; Lauria, Carmela; Vitale, Francesco; Goedert, James J.

    2009-01-01

    Purpose Before AIDS, endemic (African) Kaposi sarcoma (KS) was noted to occur in volcanic areas and was postulated to result from dirt chronically embedded in the skin of the lower extremities. The primary cause of all KS types is KS-associated herpesvirus (KSHV) infection, but co-factors contribute to the neoplasia. We investigated whether residential exposure volcanic or related soils was associated with the risk of classic Kaposi sarcoma (cKS) in Sicily. Methods Risk of incident cKS (n=141) compared to population-based KSHV seropositive controls (n=123) was estimated for residential exposure to four types of soil, categorized with maps from the European Soil Database and direct surveying. Questionnaire data provided covariates. Results Residents in communities high in luvisols were approximately 2.7-times more likely to have cKS than those in communities with no luvisols. Risk was not specific for cKS on the limbs, but it was elevated approximately 4–5-fold with frequent bathing or tap water drinking in high luvisols communities. Risk was unrelated to communities high in andosols, tephra, or clay soils. Conclusions Iron and alumino-silicate clay, major components of luvisols, may increase cKS risk, but formal investigation and consideration of other soil types and exposures are needed. PMID:19576540

  18. Thermal desorption of PCBs from contaminated soil using nano zerovalent iron.

    PubMed

    Liu, Jie; Chen, Tong; Qi, Zhifu; Yan, Jianhua; Buekens, Alfons; Li, Xiaodong

    2014-11-01

    In this study, thermal desorption was combined with the addition of nano zerovalent iron (nZVI) to remediate polychlorinated biphenyl (PCB)-contaminated soil collected from a storage point for PCB-contaminated capacitors and transformers. The thermal desorption test conditions were varied from 300 to 600 °C, both with blank soil and with 100 mg of nZVI added. Next, the effect of the amount of nZVI added (0, 20, 40, 100, 200 mg) was investigated by thermal treatment at 400 °C. The test results show that thermal desorption eliminates most of the PCB load and that the presence of nZVI clearly enhances thermal desorption. After thermal treatment at 400 °C, a removal efficiency of 94.2 % was reached, with the use of 200 mg of nZVI. At 600 °C, the PCB removal efficiency after 1 h attained 98.35 % with 100 mg of nZVI and 97.40 % without nZVI. The presence of nZVI effectively decreased both the sum and the WHO-TEQ value of the 12 dl-PCBs. PMID:24965010

  19. Risk Analysis of Metals in Soil from a Restored Coal Mining Area.

    PubMed

    Niu, Siping; Gao, Liangmin; Zhao, Junjie

    2015-08-01

    This study was conducted to evaluate ecological impacts of metals in soil from the restored Panyi coal mining area of China. Zn, Cr, Ni, Pb and Cd had significantly accumulated in the studied soil compared with regional background values (p<0.05). Geo-accumulation indices indicate that the soil was at low risk for Cu, Zn, Ni and Pb contamination, while a low to moderate risk for Cr and Cd contamination existed. The ecological impact of all the selected metals was identified by ecological soil screening levels, apart from Cr, the impact of which was determined based on Dutch Target and Intervention Values. Results suggest that plants may be significantly affected by Ni, the avian population by Zn, Pb and Cd, while mammals are possibly influenced by Cd. PMID:26067704

  20. Heavy metals in agricultural soils and crops and their health risks in Swat District, northern Pakistan.

    PubMed

    Khan, Kifayatullah; Lu, Yonglong; Khan, Hizbullah; Ishtiaq, Muhammad; Khan, Sardar; Waqas, Muhammad; Wei, Luo; Wang, Tieyu

    2013-08-01

    This study assessed the concentrations of heavy metals such as cadmium (Cd), chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni) and zinc (Zn) in agricultural soils and crops (fruits, grains and vegetable) and their possible human health risk in Swat District, northern Pakistan. Cd concentration was found higher than the limit (0.05 mg/kg) set by world health organization in 95% fruit and 100% vegetable samples. Moreover, the concentrations of Cr, Cu, Mn, Ni and Zn in the soils were shown significant correlations with those in the crops. The metal transfer factor (MTF) was found highest for Cd followed by Cr>Ni>Zn>Cu>Mn, while the health risk assessment revealed that there was no health risk for most of the heavy metals except Cd, which showed a high level of health risk index (HRI⩾10E-1) that would pose a potential health risk to the consumers. PMID:23721688

  1. Solubility and Leaching Risks of Organic Carbon in Paddy Soils as Affected by Irrigation Managements

    PubMed Central

    Yang, Shihong; Wei, Qi; Gao, Xiaoli

    2013-01-01

    Influence of nonflooding controlled irrigation (NFI) on solubility and leaching risk of soil organic carbon (SOC) were investigated. Compared with flooding irrigation (FI) paddies, soil water extractable organic carbon (WEOC) and dissolved organic carbon (DOC) in NFI paddies increased in surface soil but decreased in deep soil. The DOC leaching loss in NFI field was 63.3 kg C ha−1, reduced by 46.4% than in the FI fields. It indicated that multi-wet-dry cycles in NFI paddies enhanced the decomposition of SOC in surface soils, and less carbon moved downward to deep soils due to less percolation. That also led to lower SOC in surface soils in NFI paddies than in FI paddies, which implied that more carbon was released into the atmosphere from the surface soil in NFI paddies. Change of solubility of SOC in NFI paddies might lead to potential change in soil fertility and sustainability, greenhouse gas emission, and bioavailability of trace metals or organic pollutants. PMID:23935423

  2. Contamination features and health risk of soil heavy metals in China.

    PubMed

    Chen, Haiyang; Teng, Yanguo; Lu, Sijin; Wang, Yeyao; Wang, Jinsheng

    2015-04-15

    China faces a big challenge of environmental deterioration amid its rapid economic development. To comprehensively identify the contamination characteristics of heavy metals in Chinese soils on a national scale, data set of the first national soil pollution survey was employed to evaluate the pollution levels using several pollution indicators (pollution index, geoaccumulation index and enrichment factor) and to quantify their exposure risks posed to human health with the risk assessment model recommended by the US Environmental Protection Agency. The results showed that, due to the drastically increased industrial operations and fast urban expansion, Chinese soils were contaminated by heavy metals in varying degrees. As a whole, the exposure risk levels of soil metals in China were tolerable or close to acceptable. Comparatively speaking, children and adult females were the relatively vulnerable populations for the non-carcinogenic and carcinogenic risks, respectively. Cadmium and mercury have been identified as the priority control metals due to their higher concentrations in soils or higher health risks posed to the public, as well as, arsenic, lead, chromium and nickel. Spatial distribution pattern analysis implied that the soil metal pollutions in southern provinces of China were relatively higher than that in other provinces, which would be related to the higher geochemical background in southwest regions and the increasing human activities in southeast areas. Meanwhile, it should be noticed that Beijing, the capital of China, also has been labeled as the priority control province for its higher mercury concentration. These results will provide basic information for the improvement of soil environment management and heavy metal pollution prevention and control in China. PMID:25617996

  3. Ecotoxicological risk of polycyclic aromatic hydrocarbons (PAHs) in urban soil of Isfahan metropolis, Iran.

    PubMed

    Moore, F; Akhbarizadeh, R; Keshavarzi, B; Khabazi, S; Lahijanzadeh, A; Kermani, M

    2015-04-01

    Concentration, distribution, probable sources, and health risks of 16 polycyclic aromatic hydrocarbons (PAHs) were investigated in 52 soil samples collected within a radius 50 km from Isfahan metropolis center. Total concentration of PAHs ranged from 57.70 to 11,730.08 μg/kg averaging 2,000.56 μg/kg. Spatial PAH profiles were site-specific and higher concentration of PAHs was observed in the vicinity of industrial zones within Isfahan metropolis. The molecular indices, ring classes, and principal component analysis indicated that the sources of PAHs were both geogenic and pyrogenic. The incremental lifetime cancer risks of exposure to soil PAHs for adults and children living in the study area were 2.3×10(-2) and 2.2×10(-3), respectively. The results suggest that current PAHs levels in Isfahan metropolis soil are highly carcinogenic and may hold a serious health risk for local resident. PMID:25805371

  4. Mapping of monthly soil erosion risk of mainland Mauritius and its aggregation with delineated basins

    NASA Astrophysics Data System (ADS)

    Nigel, Rody; Rughooputh, Soonil

    2010-01-01

    This paper reports the mapping of monthly soil erosion risk on Mauritius which was carried out using GIS, decision rules and readily available data namely, monthly rainfall depth, soil types, slope and land cover. Slope and soil were first combined to produce soil erosion susceptibility followed by land cover to produce erosion sensitivity, and then rainfall to produce erosion risk. The high erosion areas of the Island have been extracted from the soil erosion risk maps, whereby these areas can face land degradation problems and can be responsible for sediment discharge into wetlands located at the outlet of drainage basins. As such, drainage basins have been delineated using automatic catchment delineation tools and their percentage of high erosion areas computed. Basins with the greatest percentage of high erosion areas and particularly those that directly have a wetland at the outlet can be given priority for soil and water conservation efforts. The mapping reported in this paper can be adapted to other countries which need an erosion assessment for the identification of high erosion areas and priority action areas.

  5. Occurrence, composition and risk assessment of antibiotics in soils from Kenya, Africa.

    PubMed

    Yang, Yuyi; Owino, Anita Awino; Gao, Yan; Yan, Xue; Xu, Chen; Wang, Jun

    2016-08-01

    Antibiotics can accumulate in soils via different ways, which may pose serious threat to ecological environment of soil and quality of agricultural products. In this study, the occurrence of 12 antibiotics including four sulfonamides (SAs), four tetracyclines (TETs) and four fluoroquinolones (FQs) was investigated in soils from four sampling sites of Kenya (Mai Mahiu, Narok, Mount Suswa Conservancy, and Juja), Africa. The soils in suburban area of Narok had the highest average concentrations of total 12 antibiotics with an average value of 43.64 μg kg(-1) dw (dry weight), followed by Mai Mahiu (26.70 μg kg(-1) dw), Juja (24.41 μg kg(-1) dw) and Mount Suswa Conservancy (12.21 μg kg(-1) dw). Sulfamethoxazole, sulfamethazine, oxytetracycline, and enrofloxacin were identified as the main antibiotics polluted in soils. Total organic carbon may influence the distribution of SAs in Narok and FQs in Juja. Ecological risk analysis based on the risk quotient showed that SAs detected in soils have higher risk compared to TETs and FQs. PMID:27189612

  6. Organic amendments for risk mitigation of organochlorine pesticide residues in old orchard soils

    USGS Publications Warehouse

    Centofantia, Tiziana; McConnell, Laura L.; Chaney, Rufus L.; Beyer, W. Nelson; Andradea, Natasha A.; Hapeman, Cathleen J.; Torrents, Alba; Nguyen, Anh; Anderson, Marya O.; Novak, J. M.; Jackson, Dana

    2015-01-01

    Performance of compost and biochar amendments for in situ risk mitigation of aged DDT, DDE and dieldrin residues in an old orchard soil was examined. The change in bioavailability of pesticide residues to Lumbricus terrestris L. relative to the unamended control soil was assessed using 4-L soil microcosms with and without plant cover in a 48-day experiment. The use of aged dairy manure compost and biosolids compost was found to be effective, especially in the planted treatments, at lowering the bioavailability factor (BAF) by 18–39%; however, BAF results for DDT in the unplanted soil treatments were unaffected or increased. The pine chip biochar utilized in this experiment was ineffective at lower the BAF of pesticides in the soil. The US EPA Soil Screening Level approach was used with our measured values. Addition of 10% of the aged dairy manure compost reduced the average hazard quotient values to below 1.0 for DDT + DDE and dieldrin. Results indicate this sustainable approach is appropriate to minimize risks to wildlife in areas of marginal organochlorine pesticide contamination. Application of this remediation approach has potential for use internationally in areas where historical pesticide contamination of soils remains a threat to wildlife populations.

  7. Organic amendments for risk mitigation of organochlorine pesticide residues in old orchard soils.

    PubMed

    Centofanti, Tiziana; McConnell, Laura L; Chaney, Rufus L; Beyer, W Nelson; Andrade, Natasha A; Hapeman, Cathleen J; Torrents, Alba; Nguyen, Anh; Anderson, Marya O; Novak, Jeffrey M; Jackson, Dana

    2016-03-01

    Performance of compost and biochar amendments for in situ risk mitigation of aged DDT, DDE and dieldrin residues in an old orchard soil was examined. The change in bioavailability of pesticide residues to Lumbricus terrestris L. relative to the unamended control soil was assessed using 4-L soil microcosms with and without plant cover in a 48-day experiment. The use of aged dairy manure compost and biosolids compost was found to be effective, especially in the planted treatments, at lowering the bioavailability factor (BAF) by 18-39%; however, BAF results for DDT in the unplanted soil treatments were unaffected or increased. The pine chip biochar utilized in this experiment was ineffective at lower the BAF of pesticides in the soil. The US EPA Soil Screening Level approach was used with our measured values. Addition of 10% of the aged dairy manure compost reduced the average hazard quotient values to below 1.0 for DDT + DDE and dieldrin. Results indicate this sustainable approach is appropriate to minimize risks to wildlife in areas of marginal organochlorine pesticide contamination. Application of this remediation approach has potential for use internationally in areas where historical pesticide contamination of soils remains a threat to wildlife populations. PMID:26716732

  8. Soil gas radon assessment and development of a radon risk map in Bolsena, Central Italy.

    PubMed

    Cinelli, G; Tositti, L; Capaccioni, B; Brattich, E; Mostacci, D

    2015-04-01

    Vulsini Volcanic district in Northern Latium (Central Italy) is characterized by high natural radiation background resulting from the high concentrations of uranium, thorium and potassium in the volcanic products. In order to estimate the radon radiation risk, a series of soil gas radon measurements were carried out in Bolsena, the principal urban settlement in this area NE of Rome. Soil gas radon concentration ranges between 7 and 176 kBq/m(3) indicating a large degree of variability in the NORM content and behavior of the parent soil material related in particular to the occurrence of two different lithologies. Soil gas radon mapping confirmed the existence of two different areas: one along the shoreline of the Bolsena lake, characterized by low soil radon level, due to a prevailing alluvial lithology; another close to the Bolsena village with high soil radon level due to the presence of the high radioactive volcanic rocks of the Vulsini volcanic district. Radon risk assessment, based on soil gas radon and permeability data, results in a map where the alluvial area is characterized by a probability to be an area with high Radon Index lower than 20 %, while probabilities higher than 30 % and also above 50 % are found close to the Bolsena village. PMID:25239677

  9. The Integrated Soil Erosion Risk Management Model of Central Java, Indonesia

    NASA Astrophysics Data System (ADS)

    Setiawan, M. A.; Stoetter, J.; Sartohadi, J.; Christanto, N.

    2009-04-01

    Many types of soil erosion modeling have been developed worldwide; each of models has its own advantage and assumption based on the originated area. Ironically, in the tropical countries where the rainfall intensity is higher than other area, the soil erosion problem gain less attention. As in Indonesia, due the inadequate supporting data and method to dealing with, the soil erosion management appears to be least prior in the policy decision. Hence, there is increasing necessity towards the initiation and integration of risk management model in the soil erosion, to prevent further land degradation problem in Indonesia. The main research objective is to generate a model which can analyze the dynamic system of soil erosion problem. This model will comprehensively consider four main aspects within the dynamic system analysis, i.e.: soil erosion rate modeling, the tolerable soil erosion rate, total soil erosion cost, and soil erosion management measures. The generating model will involve some sub-software i.e. the PC Raster to maintain the soil erosion modeling, Powersim Constructor Ver. 2.5 as the tool to analyze the dynamic system and Python Ver. 2.6.1 to build the main Graphical User Interface model. The first step addressed in this research is figuring the most appropriate soil erosion model to be applied in Indonesia based on landscape, climate, and data availability condition. This appropriate model must have the simplicity aspect in input data but still deal with the process based analysis. By using the soil erosion model result, the total soil erosion cost will be calculated both on-site and off-site effect. The total soil erosion cost will be stated in Rupiah (Indonesian currency) and Dollar. That total result is then used as one of input parameters for the tolerable soil erosion rate. Subsequently, the tolerable soil erosion rate decides whether the soil erosion rate has exceeded the allowed value or not. If the soil erosion rate has bigger value than the

  10. Removal, redistribution, and potential risks of soil Cd, Pb, and Zn after washing with various extractants.

    PubMed

    Chen, Chunle; Chen, Yanhui; Xie, Tuanhui; Wang, Ming Kuang; Wang, Guo

    2015-11-01

    The effectiveness of four different washing extractants--HCl, FeCl3, citric acid, and EDTA--in removing Cd, Pb, and Zn from polluted soil was studied. The removal of these metals, their redistribution between fractions, and the potential risks posed by them, in soils washed with the tested extractants, were examined. Although all the rounds of washing removed Cd, Pb, and Zn from soil, the first round removed more metals than subsequent rounds. Each of the four extractants had different effects on the removal of the metals. At the end of the first round of washing, HCl, EDTA, and FeCl3 were the most effective in removing Zn, Pb, and Cd, respectively. Both the single round and five successive rounds of washing with various extractants resulted in significant increases in Pb in the exchangeable/acid extractable fraction. Washing with HCl, EDTA, and FeCl3 significantly reduced potential risks (calculated as the Potential Risk Index, PRI) posed by Cd in washed soil. The first round of washing, using all extractants, increased the risks posed by Pb and Zn. However, five successive rounds of washing with FeCl3 and EDTA reduced the risk posed by Pb, and washing with citric acid and FeCl3 increased the risks posed by Zn. EDTA and HCl were better for reducing Zn risks, and successive washing with EDTA and FeCl3 were more effective in reducing Pb risks than the other extractants. Finally, five successive rounds of washing, with all the extractants, effectively reduced the potential risks posed by Cd. Among the four reagents, EDTA was advised to be the alternative of the washing reagent by significantly reducing the PRI values of Cd, Pb, and Zn. PMID:26104899

  11. Physical/chemical treatment of mixed waste soils

    SciTech Connect

    Morris, M.I. ); Alperin, E.S.; Fox, R.D. )

    1991-01-01

    This report discusses the results and findings of the demonstration testing of a physical/chemical treatment technology for mixed wastes. The principal objective of the tests was to demonstrate the capability of the low temperature thermal separation (LTTS) technology for rendering PCB-contaminated mixed waste soils as nonhazardous and acceptable for low level radioactive waste disposal. The demonstration testing of this technology was a jointly-conducted project by the US Department of Energy (DOE), the Martin Marietta Energy Systems (Energy Systems) Waste Management Technology Center at the Oak Ridge National Laboratory, and IT Corporation. This pilot-scale demonstration program testing of IT's thermal separator technology in Oak Ridge was conducted as part of the DOE Model Program. This program has private industry, regulators, and universities helping to solve DOE waste management problems. Information gained from the DOE Model is shared with the participating organizations, other federal agencies, and regulatory agencies. The following represent the most significant findings from these demonstration tests: Thermal separation effectively separated PCB contamination from a mixed waste to enable the treated soil to be managed as low level radioactive waste. At the same operating conditions, mercury contamination of 0.8 ppM was reduced to less than 0.1 ppM. The majority of uranium and technetium in the waste feeds oil remained in the treated soil. Radionuclide concentration in cyclone solids is due to carry-over of entrained particles in the exit gas and not due to volatilization/condensation. Thermal separation also effectively treated all identified semi-volatile contaminants in the waste soil to below detection limits with the exception of di-n-butylphthalate in one of the two runs. 4 refs., 1 fig., 6 tabs.

  12. Atmospheric deposition of mercury in Atlantic Forest and ecological risk to soil fauna

    NASA Astrophysics Data System (ADS)

    Cristhy Buch, Andressa; Cabral Teixeira, Daniel; Fernandes Correia, Maria Elizabeth; Vieira Silva-Filho, Emmanoel

    2014-05-01

    The increasing levels of mercury (Hg) found in the atmosphere nowadays has a great contribution from anthropogenic sources and has been a great concern in the past two decades in industrialized countries. Brazil is the seventh country with the highest rate of mercury in the atmosphere. Certainly, the petroleum refineries have significant contribution, seen that 100 million m3 of crude oil are annually processed. These refineries contribute with low generation of solid waste; however, a large fraction of Hg can be emitted to the atmosphere. There are sixteen refineries in Brazil, three of them located in the state of Rio de Janeiro. The Hg is a toxic and hazardous trace element, naturally found in the earth crust. The major input of Hg to ecosystems is through atmospheric deposition (wet and dry), being transported in the atmosphere over large distances. The forest biomes are of great importance in the atmosphere/soil cycling of elemental Hg through foliar uptake and subsequent transfer to the soil through litterfall, which play an important role as Hg sink. The Atlantic Forest of Brazil is the greater contributor of fauna and flora biodiversity in the world and, according to recent studies, this biome has the highest concentrations of mercury in litter in the world, as well as in China, at Subtropical Forest. Ecotoxicological assessments can predict the potential ecological risk of Hg toxicity in the soil can lead to impact the soil fauna and indirectly other trophic levels of the food chain within one or more ecosystems. This study aims to determine mercury levels that represent risks to diversity and functioning of soil fauna in tropical forest soils. The study is conducted in two forest areas inserted into conservation units of Rio de Janeiro state. One area is located next to an important petroleum refinery in activity since fifty-two years ago, whereas the other one is located next to other refinery under construction (beginning activities in 2015), which will

  13. Effects of soil phosphorus status on environmental risk assessment of glyphosate and glufosinate-ammonium.

    PubMed

    Laitinen, Pirkko; Siimes, Katri; Rämö, Sari; Jauhiainen, Lauri; Eronen, Liisa; Oinonen, Seija; Hartikainen, Helinä

    2008-01-01

    The increased use of herbicides poses a risk to the aquatic environment. Easy and economical methods are needed to identify the fields where specific environment protection measures are needed. Phosphorus (P) and organophosphorus herbicides compete for the same adsorption sites in soil. In this study the relationship between P obtained in routine Finnish agronomic tests (acid ammonium acetate [P(AC)]) and adsorption of glyphosate and glufosinate-ammonium was investigated to determine whether P(AC) values could be used in the risk assessment. The adsorption of glyphosate ((N-(phosphonomethyl)glycine) and glufosinate-ammonium (2-amino-4-(hydroxymethylphosphinyl)butanoic acid) was studied in a clay and a sandy loam soil enriched with increasing amounts of P added as potassium dihydrogen phosphate. Desorption was also determined for some P-enriched soil samples. The adsorption of both herbicides diminished with increasing P(AC) value. The correlations between Freundlich adsorption coefficients obtained in the adsorption tests and P(AC) were nonlinear but significant (r > 0.98) in both soils. The exponential models of the relationship between soil P(AC) values and glyphosate adsorption were found to fit well to an independent Finnish soil data set (P < 0.1 for glyphosate and P < 0.01 for glufosinate-ammonium). The desorption results showed that glufosinate-ammonium sorption is not inversely related to soil P status, and the high correlation coefficients obtained in the test of the model were thus artifacts caused by an abnormal concentration of exchangeable potassium in soil. The solved equations are a useful tool in assessing the leaching risks of glyphosate, but their use for glufosinate-ammonium is questionable. PMID:18453404

  14. Soil erosion in the Alps (spatial analysis of causes and risk assessment)

    NASA Astrophysics Data System (ADS)

    Meusburger, Katrin; Alewell, Christine

    2010-05-01

    Increasing numbers of tourists, changes in farming/cultivation techniques and global warming are expected to intensity soil erosion in the Alps. Therefore, the knowledge of the relations between triggering factors (e.g. hydrology and snow cover, stability of vegetation cover, landuse intensity etc.) and soil erosion in mountain regions will be of crucial importance in the near future. The aim of this project is the identification of causes of soil erosion in alpine environments as well as the mapping of risk areas rather than an exact quantification of sediment rates. The methods to determine erosion risk are developed within a subcatchment (30 km2) of the Furkareuss (Urseren valley, 1400-2500 m a.s.l.) in the Swiss Alps and are to be validated by upscaling to the whole catchment (80 km2). Soil erosion is linked to runoff processes. In contrast to flat regions,subsurface flow has to be considered in addition to overland flow. The latter may initiate soil slips. The valley slopes of the investigated area are affected by both water surface erosion and soil slips. Preliminary soil surveys and erosion mapping were conducted. To delineate risk zones, the various soil types found were grouped into soilscapes according to parameters with relevance for soil stability. It could be shown that soil slips occurred predominantly in the zone of hydromorphic soils, which also verified the linkage between subsurface flow and soil slips. However, a comparison between hillslopes most affected by erosion and undisturbed slopesindicated that they also differed in geology, vegetation and landuse. The weight of these triggering factors will be evaluated by spatial statistical analysis. To assess whether erosion actually increased during the last decades or whether we observe a natural equilibrium-process of degradation and regeneration, sequences of aerial photographs for seven different years starting in 1959 and recent field mapping were analysed and compared. Special attention is

  15. Human health and ecological risk assessment of soil-borne arsenic and lead: A site-specific risk assessment

    SciTech Connect

    Roy, M.; Epp, G.A.; Beukema, P.; Nieboer, E.

    1997-12-31

    Screening level site specific human health and ecological risk assessments (ERA) were conducted at a historical (1908--1921) smelting and refining site in the Niagara Region, Ontario in accordance with the recently released provincial and federal risk assessment guidelines. The purpose of the assessment was to evaluate the risk associated with elevated levels of arsenic and lead in surface soils, and to assess alternative remediation options, prior to property transfer. Future intended land use will be parkland and for the site to remain forested. The identification of potential receptors, exposure pathways, and end-points was conducted at the biological community-level. The ERA involved a toxic cue inventory of the core smelting and refining site, adjacent lands and a reference site. Development of remediation options was based on hazard assessment and the prediction of risks associated with arsenic contamination. An evaluation of remediation options and the selection of a preferred option are discussed.

  16. Soil Water Holding Capacity Mitigates Downside Risk and Volatility in US Rainfed Maize: Time to Invest in Soil Organic Matter?

    PubMed

    Williams, Alwyn; Hunter, Mitchell C; Kammerer, Melanie; Kane, Daniel A; Jordan, Nicholas R; Mortensen, David A; Smith, Richard G; Snapp, Sieglinde; Davis, Adam S

    2016-01-01

    Yield stability is fundamental to global food security in the face of climate change, and better strategies are needed for buffering crop yields against increased weather variability. Regional- scale analyses of yield stability can support robust inferences about buffering strategies for widely-grown staple crops, but have not been accomplished. We present a novel analytical approach, synthesizing 2000-2014 data on weather and soil factors to quantify their impact on county-level maize yield stability in four US states that vary widely in these factors (Illinois, Michigan, Minnesota and Pennsylvania). Yield stability is quantified as both 'downside risk' (minimum yield potential, MYP) and 'volatility' (temporal yield variability). We show that excessive heat and drought decreased mean yields and yield stability, while higher precipitation increased stability. Soil water holding capacity strongly affected yield volatility in all four states, either directly (Minnesota and Pennsylvania) or indirectly, via its effects on MYP (Illinois and Michigan). We infer that factors contributing to soil water holding capacity can help buffer maize yields against variable weather. Given that soil water holding capacity responds (within limits) to agronomic management, our analysis highlights broadly relevant management strategies for buffering crop yields against climate variability, and informs region-specific strategies. PMID:27560666

  17. Impacts of soil and water pollution on food safety and health risks in China.

    PubMed

    Lu, Yonglong; Song, Shuai; Wang, Ruoshi; Liu, Zhaoyang; Meng, Jing; Sweetman, Andrew J; Jenkins, Alan; Ferrier, Robert C; Li, Hong; Luo, Wei; Wang, Tieyu

    2015-04-01

    Environmental pollution and food safety are two of the most important issues of our time. Soil and water pollution, in particular, have historically impacted on food safety which represents an important threat to human health. Nowhere has that situation been more complex and challenging than in China, where a combination of pollution and an increasing food safety risk have affected a large part of the population. Water scarcity, pesticide over-application, and chemical pollutants are considered to be the most important factors impacting on food safety in China. Inadequate quantity and quality of surface water resources in China have led to the long-term use of waste-water irrigation to fulfill the water requirements for agricultural production. In some regions this has caused serious agricultural land and food pollution, especially for heavy metals. It is important, therefore, that issues threatening food safety such as combined pesticide residues and heavy metal pollution are addressed to reduce risks to human health. The increasing negative effects on food safety from water and soil pollution have put more people at risk of carcinogenic diseases, potentially contributing to 'cancer villages' which appear to correlate strongly with the main food producing areas. Currently in China, food safety policies are not integrated with soil and water pollution management policies. Here, a comprehensive map of both soil and water pollution threats to food safety in China is presented and integrated policies addressing soil and water pollution for achieving food safety are suggested to provide a holistic approach. PMID:25603422

  18. Ambient trace element background concentrations in soils and their use in risk assessment.

    PubMed

    Díez, M; Simón, M; Martín, F; Dorronsoro, C; García, I; Van Gestel, C A M

    2009-08-01

    The definition of ambient background concentrations (ABCs) is used in this study to assess the potential environmental risk of trace elements in soils and parent materials from Granada, Spain. Two different layers of soil (0-20 and 20-40 cm) and parent material samples were collected at 93 sites. From cumulative frequency distribution curves, ABCs for As, Co, Cu, Cr, Ni, Pb and Zn were estimated at 3.5-20, 7-23, 13-25.6, 29-66, 7-20, 15-36, and 5.5-76 mg kg(-1), respectively. Tukey box-plots were used to discriminate different concentration classes and identify potentially contaminated sites. Weakly-weathered soils (Entisols) over carbonate materials showed the lowest background contents, the most developed soils (Alfisols) over metamorphic rocks the highest ones. Outliers were mainly found near a former iron mine where arsenic concentrations were by far exceeding the corresponding regional ABC. These soils were however, not toxic to Escherichia coli and Vibrio fischeri. The prediction of site-specific ABCs together with bioavailability and toxicity assessment is a valuable tool for giving further insight into the risk of trace elements in soils. PMID:19473692

  19. Spatio-temporal analysis of soil erosion risk and runoff using AnnAGNPS

    NASA Astrophysics Data System (ADS)

    Yeshaneh, Eleni; Wagner, Wolfgang; Blöschl, Günter

    2014-05-01

    Soil erosion is one form of land degradation in Ethiopia deteriorating the fertility and productivity of the land. This fact indicates the need to delineate high erosion risk areas for appropriate soil and conservation measures. Land use/cover change is one of the important factors in soil erosion. This study attempts test and implement AnnAGNPS model to estimate the spatio-temporal patterns of soil erosion and runoff associated with land use changes in the past 50 years in the 9900 ha upstream part of the Koga catchment. High erosion risk areas will then be delineated for simulation of the appropriate soil and water conservation measures that would reduce the soil loss. The study is based on two years high temporal resolution data on discharge, sediment, and rain fall accompanied by historical land use/cover data generated from satellite imagery. In addition, it uses several documented physical parameters of the study area. The Koga catchment is one of the agriculture dominated typical catchments in the North Western Ethiopian highlands with high population density that lead to increased pressure on natural resources.

  20. Factors affecting paddy soil arsenic concentration in Bangladesh: prediction and uncertainty of geostatistical risk mapping.

    PubMed

    Ahmed, Zia U; Panaullah, Golam M; DeGloria, Stephen D; Duxbury, John M

    2011-12-15

    Knowledge of the spatial correlation of soil arsenic (As) concentrations with environmental variables is needed to assess the nature and extent of the risk of As contamination from irrigation water in Bangladesh. We analyzed 263 paired groundwater and paddy soil samples covering highland (HL) and medium highland-1 (MHL-1) land types for geostatistical mapping of soil As and delineation of As contaminated areas in Tala Upazilla, Satkhira district. We also collected 74 non-rice soil samples to assess the baseline concentration of soil As for this area. The mean soil As concentrations (mg/kg) for different land types under rice and non-rice crops were: rice-MHL-1 (21.2)>rice-HL (14.1)>non-rice-MHL-1 (11.9)>non-rice-HL (7.2). Multiple regression analyses showed that irrigation water As, Fe, land elevation and years of tubewell operation are the important factors affecting the concentrations of As in HL paddy soils. Only years of tubewell operation affected As concentration in the MHL-1 paddy soils. Quantitatively similar increases in soil As above the estimated baseline-As concentration were observed for rice soils on HL and MHL-1 after 6-8 years of groundwater irrigation, implying strong retention of As added in irrigation water in both land types. Application of single geostatistical methods with secondary variables such as regression kriging (RK) and ordinary co-kriging (OCK) gave little improvement in prediction of soil As over ordinary kriging (OK). Comparing single prediction methods, kriging within strata (KWS), the combination of RK for HL and OCK for MHL-1, gave more accurate soil As predictions and showed the lowest misclassification of declaring a location "contaminated" with respect to 14.8 mg As/kg, the highest value obtained for the baseline soil As concentration. Prediction of soil As buildup over time indicated that 75% or the soils cropped to rice would contain at least 30 mg/L As by the year 2020. PMID:22055452

  1. Heavy metal speciation and risk assessment in dry land and paddy soils near mining areas at Southern China.

    PubMed

    Liu, Guannan; Wang, Juan; Zhang, Erxi; Hou, Jing; Liu, Xinhui

    2016-05-01

    Heavy metal contamination of soils has been a long-standing environmental problem in many parts of the world, and poses enormous threats to ecosystem and human health. Speciation of heavy metals in soils is crucial to assessing environmental risks from contaminated soils. In this study, total concentrations and speciation of As, Cd, Cr, Cu, Mn, Ni, Pb, and Zn were measured for agricultural soils near mines along the Diaojiang River in Guangxi Zhuang Autonomy Region, China. The sources of heavy metals in soils also were identified to assess their effect on speciation distribution of soil heavy metals. Furthermore, the speciation distribution of Cd and Zn, main soil heavy metal pollutants, in dry land and paddy soils were compared. Results showed that there were two severely polluted regions near mine area reaching alarming pollution level. As, Cd, Pb, and Zn were more affected by mining activities, showing very strong pollution level in soils. The mean percentage of exchangeable and carbonate fraction was highest and up to 46.8 % for Cd, indicating a high environmental risk. Greater bioavailable fractions of As, Cd, Cu, Mn, Pb, and Zn were found in soils heavily polluted by mining activities, whereas Cr and Ni as geogenic elements in the stable residual fraction. In addition, in the dry land soils, reducible fraction proportion of Cd was higher than that in the paddy soils, whereas exchangeable and carbonate fraction of Cd was lower than that in the paddy soils. Oxidizable fraction of Zn was higher in the paddy soils than that in the dry land soils. The results indicate that the sources of soil heavy metals and land types affect heavy metal speciation in the soil and are significant for environmental risk assessment of soil heavy metal pollutions. PMID:26801928

  2. A Linkage Between Parent Materials of Soil and Potential Risk of Heavy Metals in Yunnan province, China

    NASA Astrophysics Data System (ADS)

    Cheng, X.

    2015-12-01

    A large area exceeding soil quality standards for heavy metals in South western China has been identified previously reported on a nationwide survey of soil pollution, yet the ecological risk of heavy metal in soil is unknown or uncertainty.To assess thoroughly the ecological risk in this region, seven soil profiles with a depth of 2m on the different parent materials of soil were conducted in Yunnan province, China, and the level of total concentrations and the fraction of water soluble, ion exchangeable, carbonates, humic acid, iron and manganese oxides and organic matter of As, Cd, Hg and Pb was investigated in soil profiles. The results indicate that parent materials of soil critically influenced the ecological risk of heavy metal.The fraction of water soluble and ion exchangeable of Cd and Hg in alluvial material and in terrigenous clastic rocks showed 2-6 times higher than those in carbonate rock; As and Pb has almost same fraction of water soluble and ion exchangeable in three parent materials of soil.The findings suggest that parent materials of soil play a critical role in ecological risk of heavy metal.Thus, more studies are needed to better understand a linkage between the parent materials of soil, different soil-forming processes and the potential risk of heavy metals under various geographic conditions, which is the key for the evaluating soil quality and food safety. Those soils with high concentration of Cd and Hg originated alluvial material and terrigenous clastic rocks need to be continuously monitored before determining a cost-effective remediation technology. Keywords: Heavy metals; Ecological risk;Parent materials of soil;China

  3. A risk assessment example for soil invertebrates using spatially explicit agent-based models.

    PubMed

    Reed, Melissa; Alvarez, Tania; Chelinho, Sónia; Forbes, Valery; Johnston, Alice; Meli, Mattia; Voss, Frank; Pastorok, Rob

    2016-01-01

    Current risk assessment methods for measuring the toxicity of plant protection products (PPPs) on soil invertebrates use standardized laboratory conditions to determine acute effects on mortality and sublethal effects on reproduction. If an unacceptable risk is identified at the lower tier, population-level effects are assessed using semifield and field trials at a higher tier because modeling methods for extrapolating available lower-tier information to population effects have not yet been implemented. Field trials are expensive, time consuming, and cannot be applied to variable landscape scenarios. Mechanistic modeling of the toxicological effects of PPPs on individuals and their responses combined with simulation of population-level response shows great potential in fulfilling such a need, aiding ecologically informed extrapolation. Here, we introduce and demonstrate the potential of 2 population models for ubiquitous soil invertebrates (collembolans and earthworms) as refinement options in current risk assessment. Both are spatially explicit agent-based models (ABMs), incorporating individual and landscape variability. The models were used to provide refined risk assessments for different application scenarios of a hypothetical pesticide applied to potato crops (full-field spray onto the soil surface [termed "overall"], in-furrow, and soil-incorporated pesticide applications). In the refined risk assessment, the population models suggest that soil invertebrate populations would likely recover within 1 year after pesticide application, regardless of application method. The population modeling for both soil organisms also illustrated that a lower predicted average environmental concentration in soil (PECsoil) could potentially lead to greater effects at the population level, depending on the spatial heterogeneity of the pesticide and the behavior of the soil organisms. Population-level effects of spatial-temporal variations in exposure were elucidated in the

  4. Ecological risk assessment of radiological exposure to depleted uranium in soils at a weapons testing facility.

    SciTech Connect

    Hlohowskyj, I.; Cheng, J.; Tsao, C.; Environmental Assessment

    2004-01-01

    The potential for unacceptable risks to biota from radiological exposure to depleted uranium (DU) in soils was evaluated at two sites where DU weapons testing had been conducted in the past. A screening risk assessment was conducted to determine if measured concentrations of DU-associated radionuclides in site soils exceed radionuclide levels considered protective of biota. While concentrations of individual radionuclides did not exceed acceptable levels, total radionuclide concentrations could result in potentially unacceptable doses to exposed biota. Thus, a receptor-specific assessment was conducted to estimate external and internal radiological doses to vegetation and wildlife known or expected to occur at the sites. Wildlife evaluated included herbivores, omnivores, and top-level predators. Internal dose estimates to wildlife considered exposure via fugitive dust inhalation and soil and food ingestion; root uptake was the primary exposure route evaluated for vegetation. Total doses were compared with acceptable dose levels of 1.0 and 0.1 rad/day for vegetation and wildlife, respectively, with potentially unacceptable risks indicated for doses exceeding these levels. All estimated doses were below or approximated acceptable levels, typically by an order of magnitude or more. These results indicate that current levels of DU in soils do not pose unacceptable radiological risks to biota at the sites evaluated.

  5. A review of soil heavy metal pollution from mines in China: pollution and health risk assessment.

    PubMed

    Li, Zhiyuan; Ma, Zongwei; van der Kuijp, Tsering Jan; Yuan, Zengwei; Huang, Lei

    2014-01-15

    Heavy metal pollution has pervaded many parts of the world, especially developing countries such as China. This review summarizes available data in the literature (2005-2012) on heavy metal polluted soils originating from mining areas in China. Based on these obtained data, this paper then evaluates the soil pollution levels of these collected mines and quantifies the risks these pollutants pose to human health. To assess these potential threat levels, the geoaccumulation index was applied, along with the US Environmental Protection Agency (USEPA) recommended method for health risk assessment. The results demonstrate not only the severity of heavy metal pollution from the examined mines, but also the high carcinogenic and non-carcinogenic risks that soil heavy metal pollution poses to the public, especially to children and those living in the vicinity of heavily polluted mining areas. In order to provide key management targets for relevant government agencies, based on the results of the pollution and health risk assessments, Cd, Pb, Cu, Zn, Hg, As, and Ni are selected as the priority control heavy metals; tungsten, manganese, lead-zinc, and antimony mines are selected as the priority control mine categories; and southern provinces and Liaoning province are selected as the priority control provinces. This review, therefore, provides a comprehensive assessment of soil heavy metal pollution derived from mines in China, while identifying policy recommendations for pollution mitigation and environmental management of these mines. PMID:24076505

  6. VERTICAL PROFILING OF VOCS IN GROUNDWATER AND SOIL VAPORS TO EVALUATE THE RISK OF VAPOR INTRUSION

    EPA Science Inventory

    The Draft EPA Subsurface Vapor Intrusion Guidance Document was established to address the incremental increases in exposures and risks from subsurface contaminants that may be intruding into indoor air@. The document utilizes attenuation factors based on indoor air/soil gas or i...

  7. Scientific Opportunity to Reduce Risk in Groundwater and Soil Remediation

    SciTech Connect

    Pierce, Eric M.; Freshley, Mark D.; Hubbard, Susan S.; Looney, Brian B.; Zachara, John M.; Liang, Liyuan; Lesmes, D.; Chamberlain, G. M.; Skubal, Karen L.; Adams, V.; Denham, Miles E.; Wellman, Dawn M.

    2009-08-25

    In this report, we start by examining previous efforts at linking science and DOE EM research with cleanup activities. Many of these efforts were initiated by creating science and technology roadmaps. A recurring feature of successfully implementing these roadmaps into EM applied research efforts and successful cleanup is the focus on integration. Such integration takes many forms, ranging from combining information generated by various scientific disciplines, to providing technical expertise to facilitate successful application of novel technology, to bringing the resources and creativity of many to address the common goal of moving EM cleanup forward. Successful projects identify and focus research efforts on addressing the problems and challenges that are causing “failure” in actual cleanup activities. In this way, basic and applied science resources are used strategically to address the particular unknowns that are barriers to cleanup. The brief descriptions of the Office of Science basic (Environmental Remediation Science Program [ERSP]) and EM’s applied (Groundwater and Soil Remediation Program) research programs in subsurface science provide context to the five “crosscutting” themes that have been developed in this strategic planning effort. To address these challenges and opportunities, a tiered systematic approach is proposed that leverages basic science investments with new applied research investments from the DOE Office of Engineering and Technology within the framework of the identified basic science and applied research crosscutting themes. These themes are evident in the initial portfolio of initiatives in the EM groundwater and soil cleanup multi-year program plan. As stated in a companion document for tank waste processing (Bredt et al. 2008), in addition to achieving its mission, DOE EM is experiencing a fundamental shift in philosophy from driving to closure to enabling the long-term needs of DOE and the nation.

  8. Residues and risks of veterinary antibiotics in protected vegetable soils following application of different manures.

    PubMed

    Zhang, Haibo; Zhou, Yang; Huang, Yujuan; Wu, Longhua; Liu, Xinghua; Luo, Yongming

    2016-06-01

    The protected vegetable farming is a style of high frequent rotation farming which requires a huge amount of fertilizers to maintain soil fertility. A total of 125 surface soils covering from east to west of China were sampled for the analysis of 17 antibiotics in order to identify antibiotics contamination caused by long-term manures application. The results indicate that the agricultural land has accumulated a statistically significantly higher antibiotics concentration than conventional open croplands. The maximum oxytetracycline concentration was 8400 μg kg(-1), the highest level that has ever been reported for oxytetracycline in soils. The residual concentration is decided by both plant duration and manure type. Short-term (<5 years) planting shows the highest residues of tetracyclines and fluoroquinolones in the soils. The organic farming characteristic of applying commercial compost as a single fertilizer in planting shows the lowest antibiotics residue in the soils on the whole. Principal component analysis suggests that the various combinations of antibiotic compounds in the soil may be used to trace the manure source. The antibiotics in soil may threaten water quality through contamination by diffusion. Ciprofloxacin and sulfachinoxalin are calculated to be a higher migration risk to surface waters, hence their environmental fate requires further study. PMID:26971176

  9. Approach to study of Cu, Ni and Zn content in soil for ecotoxicological risk assessment

    NASA Astrophysics Data System (ADS)

    Boluda, R.; Marimon, L.; Gil, C.; Roca-Pérez, L.

    2009-04-01

    Current Spanish legislation on contaminated soils defines contaminated soil as "that whose characteristics have been negatively altered by the presence of dangerous human-derived chemical components whose concentration is such that it is an unacceptable risk for human health or the environment and has been expressly declared as such by legal ruling". Regarding heavy metals, the Spanish Autonomous Communities will promote measures to obtain generic reference values to declare a soil to be contaminated. In the Valencian Community, these reference values still do not exist. So if the protection of ecosystems is considered a priority to declare a soil to be contaminated and to assess the level of risk, emergency toxicity tests and seed growth in land plants are resorted to, or tests with aquatic organisms or other experiments with leached soils obtained by standard procedures are carried out. We studied the toxic effects of calcareous contaminated soils by Cu, Ni and Zn on marine bacterium Vibrio fisheri (MicrotoxR test assay) (1) and on barley (Hordeum vulgare L.) in plate (germination index) (2) and pot (UNE 77301) (3) experiments for the purpose of establishing the Cu, Ni and Zn concentrations in soil which may lead to toxicity in order to observe, therefore, whether there is any likelihood of these pollutants coming into contact with any receptor and if adverse effects exist for living beings and the environment. The results showed significant differences among the three types of tests done but, in all cases, the concentrations needed to reflect toxicity effect on organisms were around 20 -70 (Cu and Ni) to 1000 (Zn) times higher than the levels of the control soils. The sensitivity order of the bio-assay was: (1) < (3) < (2). We would like to thank Spanish government-MICINN for partial funding and support (MICINN, project CGL2006-09776).

  10. [Spatial Distribution and Potential Ecological Risk Assessment of Heavy Metals in Soils and Sediments in Shunde Waterway, Southern China].

    PubMed

    Cai, Yi-min; Chen, Wei-ping; Peng, Chi; Wang, Tie-yu; Xiao, Rong-bo

    2016-05-15

    Environmental quality of soils and sediments around water source area can influence the safety of potable water of rivers. In order to study the pollution characteristics, the sources and ecological risks of heavy metals Zn, Cr, Pb, Cu, Ni and Cd in water source area, surface soils around the waterway and sediments in the estuary of main tributaries were collected in Shunde, and ecological risks of heavy metals were assessed by two methods of potential ecological risk assessment. The mean contents of Zn, Cr, Pb, Cu, Ni and Cd in the surface soils were 186.80, 65.88, 54.56, 32.47, 22.65 and 0.86 mg · kg⁻¹ respectively, and they were higher than their soil background values except those of Cu and Ni. The mean concentrations of Zn, Cr, Pb, Cu, Ni and Cd in the sediments were 312.11, 111.41, 97.87, 92.32, 29.89 and 1.72 mg · kg⁻¹ respectively, and they were higher than their soil background values except that of Ni. The results of principal component analysis illustrated that the main source of Cr and Ni in soils was soil parent materials, and Zn, Pb, Cu and Cd in soils mainly came from wastewater discharge of local manufacturing industry. The six heavy metals in sediments mainly originated from industry emissions around the Shunde waterway. The results of potential ecological risk assessment integrating environmental bioavailability of heavy metals showed that Zn, Cu, Pb and Ni had a slight potential ecological risk. Cd had a slight potential ecological risk in surface soils, but a moderate potential ecological risk in surfaces sediments. Because the potential ecological risk assessment integrating environmental bioavailability of heavy metals took the soil properties and heavy metal forms into account, its results of risks were lower than those of Hakanson methods, and it could avoid overestimating the potential risks of heavy metals. PMID:27506029

  11. Heavy Metal Contamination in Rice-Producing Soils of Hunan Province, China and Potential Health Risks

    PubMed Central

    Zeng, Fanfu; Wei, Wei; Li, Mansha; Huang, Ruixue; Yang, Fei; Duan, Yanying

    2015-01-01

    We studied Cd, Cr, As, Ni, Mn, Pb, and Hg in three agricultural areas of Hunan province and determined the potential non-carcinogenic and carcinogenic risks for residents. Soil and brown rice samples from Shimen, Fenghuang, and Xiangtan counties were analyzed by atomic absorption spectroscopy. Soil levels of Cd and Hg were greatest, followed by As and Ni. The mean concentrations of heavy metals in brown rice were Cd 0.325, Cr 0.109, As 0.344, Ni 0.610, Mn 9.03, Pb 0.023, and Hg 0.071 mg/kg, respectively. Cd and Hg had greater transfer ability from soil to rice than the other elements. Daily intake of heavy metals through brown rice consumption were estimated to be Cd 2.30, Cr 0.775, As 2.45, Ni 4.32, Pb 0.162, Mn 64.6 and Hg 0.503 µg/(kg·day), respectively. Cd, Hg and As Hazard Quotient values were greater than 1 and Cd, Cr, As and Ni Cancer Risk values were all greater than 10−4. The total non-carcinogenic risk factor was 14.6 and the total carcinogenic risk factor was 0.0423. Long-term exposure to heavy metals through brown rice consumption poses both potential non-carcinogenic and carcinogenic health risks to the local residents. PMID:26670240

  12. Cancer risks from soil emissions of volatile organic compounds at the Lawrence Livermore National Laboratory

    SciTech Connect

    Dibley, V. R., LLNL

    1998-02-01

    The emission isolation flux chamber (EIFC) methodology was applied to Superfund investigations at the Lawrence Livermore National Laboratory Site 300 to determine if on-site workers were exposed to VOCs volatilizing from the subsurface and what, if any, health risks could be attributed to the inhalation of the VOCs volatilizing from the subsurface. During July and August of 1996, twenty, eighteen, and twenty six VOC soil vapor flux samples were collected in the Building 830, 832, and 854 areas, respectively using EIFCS. The VOC concentrations in the vapor samples were used to calculate soil flux rates which were used as input into an air dispersion model to calculate ambient air exposure-point concentrations. The exposure-point concentrations were compared to EPA Region IX Preliminary Remediation Goals (PRGs). Buildings 830 and 832 exposure-point concentrations were less then the PRGs therefore no cancer risks were calculated. The cancer risks for Building 854 ranged from 1.6 x 10{sup -7} to 2.1 x 10{sup -6}. The resultant inhalation cancer risks were all within the acceptable range, implying that on-site workers were not exposed to VOC vapors volatilizing from the subsurface soil that could have significant cancer risks. Therefore remediation in these areas would not be necessary.

  13. Soil physical conditions as livestock treading effect in tropical Agroecosystem of dryland and strategies to mitigate desertification risk

    NASA Astrophysics Data System (ADS)

    Florentino, A.; Torres, D.; Ospina, A.; Contreras, J.; Palma, Z.; Silvera, J.

    2012-04-01

    Soil degradation in natural ecosystem of arid and semi-arid zones of Venezuela due to livestock treading (goats) it is an important problem that affect their environment functions; increase soil erodibility, bulk density, water losses and reduce porosity, water infiltration rate and soil structural stability. The presence of biological crust (BSC) in this type of soil it is very common. The objective of this study was to evaluate the soil surface physical quality through the use of selected indicators, mainly some of that related to structural stability, infiltrability and the prediction of soil erosion risk in two zones of Lara state: 1) Quíbor (QUI) and 2) Humocaro Bajo (HB). The study was conducted on two selected plots (30 m x 20 m) in each zone, with natural vegetation and BSC cover, with areas affected by different degree of compaction due to treading in the paths where the goats are moving. Five sites per plot (50 cm x 50 cm) under vegetation cover and five sites over the path with bare soil were sampled (0-7,5 and 7,5-15 cm depth). The results showed that soil macroaggregate stability (equivalent diameter of aggregates >0,25 mm) was significantly higher (p<0,05 %) in soil with vegetation cover and BSC compared with bare soil. Sealing index, as a measure of aggregate stability, determined in laboratory under simulated rain and expressed as hydraulic conductivity of soil surface sealing (Kse), decreased with decreasing soil vegetation cover and the presence of BSC. However, Ksei (i: inicial) and Ksef (f: final) were significantly greater in soil with more than 75 % of BSC in comparison to bare soils. The sealing index it is used to for to estimate changes in soil water losses. As the sealing index increases, the susceptibility of the soil to undergo surface sealing or slaking decrease. These results suggested that soil physical properties are potential indicators of soil quality with regard to soil erodibility and showed that soils under vegetation cover had

  14. Characterization and fate of polychlorinated biphenyls, polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans in soils and sediments at the Portsmouth Gaseous Diffusion Plant, Ohio.

    PubMed

    Kruse, Natalie A; Bowman, Jennifer; Lopez, Dina; Migliore, Elizabeth; Jackson, Glen P

    2014-11-01

    The U.S. Department of Energy Portsmouth Gaseous Diffusion Plant is in the early stages of decommissioning and decontamination. During operations, the site drew a large amount of electric power and had multiple large switchyards on site. These are a source of polychlorinated biphenyls (PCB) contamination to both on-site and off-site streams. Some soil remediation has been completed in the main switchyard. During 2011 and 2012, fifteen sites were sampled at the surface (<10 cm) and subsurface (20-30 cm) to characterize the extent of PCB contamination, to identify weathering and migration of PCB contamination and to explore potential polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) contamination due to transformer fires and explosions in the 1950s and 1960s. Stagnant sites tended to exhibit more migration of contamination to deeper sediments than sites with fast-moving waters, and the highest concentrations were found at the bottom of a settling pond. A signature set of five dioxin-like PCBs were consistently found across the site with higher concentrations in carbon rich surface sediments. PCB concentrations had a significant inverse correlation with clay content, suggesting that PCBs did not bind to clays at this site. Remediation has reduced PCB concentrations throughout the site compared to levels found in previous studies and long-term upkeep of sediment lagoons is necessary to retain PCB and dioxin-rich sediments. The flow regimen, organic carbon and clay content play a very important role in the fate of PCBs in the environment at the surface as well as downward migration. PMID:25113188

  15. A framework for assessing ecological risks of petroleum-derived materials in soil

    SciTech Connect

    Suter, G.W. II

    1997-05-01

    Ecological risk assessment estimates the nature and likelihood of effects of human actions on nonhuman organisms, populations, and ecosystems. It is intended to be clearer and more rigorous in its approach to estimation of effects and uncertainties than previously employed methods of ecological assessment. Ecological risk assessment is characterized by a standard paradigm that includes problem formulation, analysis of exposure and effects, risk characterization, and communication with a risk manager. This report provides a framework that applies the paradigm to the specific problem of assessing the ecological risks of petroleum in soil. This type of approach requires that assessments be performed in phases: (1) a scoping assessment to determine whether there is a potential route of exposure for potentially significant ecological receptors; (2) a screening assessment to determine whether exposures could potentially reach toxic levels; and (3) a definitive assessment to estimate the nature, magnitude, and extent of risks. The principal technical issue addressed is the chemically complex nature of petroleum--a complexity that may be dealt with by assessing risks on the basis of properties of the whole material, properties of individual chemicals that are representative of chemical classes, distributions of properties of the constituents of chemical classes, properties of chemicals detected in the soil, and properties of indicator chemicals. The advantages and feasibility of these alternatives are discussed. The report concludes with research recommendations for improving each stage in the assessment process.

  16. Mapping Erosion Risk in California's Rangelands Using the Universal Soil Loss Equation (USLE)

    NASA Astrophysics Data System (ADS)

    Salls, W. B.; O'Geen, T. T.

    2015-12-01

    Soil loss constitutes a multi-faceted problem for agriculture: in addition to reducing soil fertility and crop yield, it compromises downstream water quality. Sediment itself is a major issue for aquatic ecosystems, but also serves as a vector for transporting nutrients, pesticides, and pathogens. Rangelands are thought to be a contributor to water quality degradation in California, particularly in the northern Coast Range. Though total maximum daily loads (TMDLs) have been imposed in some watersheds, and countless rangeland water quality outreach activities have been conducted, the connection between grazing intensity recommendations and changes in water quality is poorly understood at the state level. This disconnect gives rise to poorly informed regulations and discourages adoption of best management practices by ranchers. By applying the Universal Soil Loss Equation (USLE) at a statewide scale, we highlighted areas most prone to erosion. We also investigated how two different grazing intensity scenarios affect modeled soil loss. Geospatial data layers representing the USLE parameters—rainfall erosivity, soil erodibility, slope length and steepness, and cover—were overlaid to model annual soil loss. Monitored suspended sediment data from a small North Coast watershed with grazing as the predominant land use was used to validate the model. Modeled soil loss values were nearly one order of magnitude higher than monitored values; average soil loss feeding the downstream-most site was modeled at 0.329 t ha-1 yr-1, whereas storm-derived sediment passing the site over two years was calculated to be 0.037 t ha-1 yr-1. This discrepancy may stem from the fact that the USLE models detached sediment, whereas stream monitoring reflects sediment detached and subsequently transported to the waterway. Preliminary findings from the statewide map support the concern that the North Coast is particularly at risk given its combination of intense rain, erodible soils, and

  17. Efficiency of soil organic and inorganic amendments on the remediation of a contaminated mine soil: I. Effects on trace elements and nutrients solubility and leaching risk.

    PubMed

    Pardo, T; Bernal, M P; Clemente, R

    2014-07-01

    A mesocosm experiment, in columns, was conducted in a growth chamber to assess the viability of two organic materials (pig slurry and compost; in combination with hydrated lime) for the remediation of a highly acidic and trace elements (TEs) contaminated mine soil and the reduction of its associated leaching risks. Their influence on the evolution throughout the soil depth of the physicochemical properties (including TEs mobility) of the soil and soil solution (in situ periodic collection) and on Lolium perenne growth and foliar TEs accumulation was evaluated. Soluble and extractable concentrations of the different TEs were considerably high, although the organic amendments (with lime) and lime addition successfully decreased TEs mobility in the top soil layer, as a consequence of a rise in pH and changes in the redox conditions. Compost and pig slurry increased the soluble organic-C and dissolved N, K and P of the soil, producing a certain downwards displacement of N and K. The organic amendments allowed the growth of L. perenne in the soil, thus indicating improvement of soil conditions, but elevated TEs availability in the soil led to toxicity symptoms and abnormally high TEs concentrations in the plants. An evaluation of the functioning and ecotoxicological risks of the remediated soils is reported in part II: this allows verification of the viability of the amendments for remediation strategies. PMID:24875879

  18. Potential risk of biochar-amended soil to aquatic systems: an evaluation based on aquatic bioassays.

    PubMed

    Bastos, A C; Prodana, M; Abrantes, N; Keizer, J J; Soares, A M V M; Loureiro, S

    2014-11-01

    It is vital to address potential risks to aquatic ecosystems exposed to runoff and leachates from biochar-amended soils, before large scale applications can be considered. So far, there are no established approaches for such an assessment. This study used a battery of bioassays and representative aquatic organisms for assessing the acute toxicity of water-extractable fractions of biochar-amended soil, at reported application rates (80 t ha(-1)). Biochar-amended aqueous soil extracts contained cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), manganese (Mn), zinc (Zn), nickel (Ni), lead (Pb), arsenic (As) and mercury (Hg) (Σmetals 96.3 µg l(-1)) as well as the 16 priority PAHs defined by the U.S. Environmental Protection Agency (Σ16PAHs 106 ng l(-1)) at contents in the range of current EU regulations for surface waters. Nevertheless, acute exposure to soil-biochar (SB) extracts resulted in species-specific effects and dose-response patterns. While the bioluminescent marine bacterium Vibrio fischeri was the most sensitive organism to aqueous SB extracts, there were no effects on the growth of the microalgae Pseudokirchneriella subcapitata. In contrast, up to 20 and 25% mobility impairment was obtained for the invertebrate Daphnia magna upon exposure to 50 and 100% SB extract concentrations (respectively). Results suggest that a battery of rapid and cost-effective aquatic bioassays that account for ecological representation can complement analytical characterization of biochar-amended soils and risk assessment approaches for surface and groundwater protection. PMID:25213286

  19. Ecological risks of polycyclic musk in soils irrigated with reclaimed municipal wastewater.

    PubMed

    Wang, Meie; Peng, Chi; Chen, Weiping; Markert, Bernd

    2013-11-01

    HHCB (1,3,4,6,7,8-hexahydro-4,6,6,7,8-hexamethylcyclopenta-c-2-benzopyrane) and AHTN (7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene) are found in reclaimed municipal wastewater. They may accumulate in soils receiving long-term application of reclaimed water thus adversely impact the soil biota. We evaluated the extent of their accumulation in receiving soils using HYDRUS-1D based on reclaimed municipal wastewater irrigation data at a public park in Beijing. The potential for ecological harms were assessed according to tested and reported outcomes of acute toxicity tests using wheat (Triticum aetivum L), earthworm (Eisenia fetida) and springtail (Bourletiella hortensis) as target organisms. Results of comparison among EC50 values from wheat, earthworm and springtail showed the EC50 value for root elongation inhibition of wheat germination was the least. Based on the least EC50, predicted no effect concentration in soils were 290 and 320ng /g for HHCB and ATHN, respectively. Comparable results from simulation to experimental and field investigating date validated the using of HYDRUS-1D in the work. Results of risk prediction showed it would take 243 and 666 years for HHCB and AHTN accumulated in soils at current irrigation practice to reach the levels for the resulting risk characterization ratios (RCRs) to cause potential ecosystem harms. PMID:23978598

  20. Soil Heavy Metal Pollution and Risk Assessment in Shenyang Industrial District, Northeast China

    PubMed Central

    Jiao, Xudong; Teng, Yanguo; Zhan, Yanhong; Wu, Jin; Lin, Xueyu

    2015-01-01

    To investigate the soil heavy metal pollution characteristics and ecological risk factors, 42 samples and six typical soil profiles were collected from the Shenyang industrial district in northeast China and were analyzed for contents of titanium (Ti), copper (Cu), lead (Pb), zinc (Zn), cobalt (Co), nickel (Ni), chromium (Cr) and arsenic (As). Through statistical analysis, it was found that the mean concentrations were higher than their background values (Ti = 4.77>3.8g/kg, Cu = 33.75>22.6 mg/kg, Pb = 45.95>26 mg/kg, Zn = 81.54>74.2 mg/kg, Co = 12.91>12.7 mg/kg, Ni = 32.26>26.9 mg/kg, Cr = 83.36>61 mg/kg and As = 13.69>11.2 mg/kg) but did not exceed their corresponding pollution limits for the Chinese Environmental Quality Standard for Soils (State Environmental Protection Administration of China, 1995). There were contamination hotspots that may be caused by human activities such as smelting plants and sewage irrigation. The Enrichment Factor and Ecological Risk Index were used to identify the anthropogenic contamination and ecological risks of heavy metals. Soil in the study area could be considered lightly or partially polluted by heavy metals. According to clustering analysis, distinct groups of heavy metals were discriminated between natural or anthropogenic sources. PMID:25997173

  1. Pharmaceuticals in soils of lower income countries: Physico-chemical fate and risks from wastewater irrigation.

    PubMed

    Lees, Katherine; Fitzsimons, Mark; Snape, Jason; Tappin, Alan; Comber, Sean

    2016-09-01

    Population growth, increasing affluence, and greater access to medicines have led to an increase in active pharmaceutical ingredients (APIs) entering sewerage networks. In areas with high wastewater reuse, residual quantities of APIs may enter soils via irrigation with treated, partially treated, or untreated wastewater and sludge. Wastewater used for irrigation is currently not included in chemical environmental risk assessments and requires further consideration in areas with high water reuse. This study critically assesses the contemporary understanding of the occurrence and fate of APIs in soils of low and lower-middle income countries (LLMIC) in order to contribute to the development of risk assessments for APIs in LLMIC. The physico-chemical properties of APIs and soils vary greatly globally, impacting on API fate, bioaccumulation and toxicity. The impact of pH, clay and organic matter on the fate of organic ionisable compounds is discussed in detail. This study highlights the occurrence and the partitioning and degradation coefficients for APIs in soil:porewater systems, API usage data in LLMICS and removal rates (where used) within sewage treatment plants as key areas where data are required in order to inform robust environmental risk assessment methodologies. PMID:27349834

  2. Biological quality of soils containing hydrocarbons and efficacy of ecological risk reduction by bioremediation alternatives

    SciTech Connect

    Stewart, A.J.; Napolitano, G.E.; Sample, B.E.

    1996-06-01

    This project provides technical support to the Petroleum Environmental Research Forum (PERF; a consortium of petroleum companies) on environmentally acceptable endpoints that may be used to help assess the ecological risk of petroleum hydrocarbon residuals in soils. The project, was designed in consultation with PERF representatives and focuses on the relationship between {open_quotes}chemically available{close_quotes} and {open_quotes}biologically available{close_quotes} measurements of petroleum hydrocarbon compounds in soils, a discrepancy of considerable interest to the petroleum industry. Presently, clean-up standards for soils contaminated with total petroleum hydrocarbon (TPH) constituents are based on concentrations of TPH, as measured in solvent extracts of soil samples. Interestingly, TPH includes a complex mixture of compounds which differ from one another in molecular weight and toxicity. Based on various studies with insecticides, herbicides and metals, some compounds apparently can slowly permeate into soil particles. If this situation occurs, the particle-embedded compounds may be extractable by use of organic solvents, and yet be unavailable biologically. This hypothesis serves as the central focus for our study. If this hypothesis is correct, then soil clean-up standards based on solvent-extractable TPH data may be more stringent than necessary to achieve a desired level of environmental risk. The economic significance of this possibility is considerable, because clean-up costs to achieve a low-risk status would, in most cases, be lower than those needed to achieve a standard based on present limits, which are based on measurements of {open_quotes}extractable{close_quotes} TPH.

  3. Health risk estimates for groundwater and soil contamination in the Slovak Republic: a convenient tool for identification and mapping of risk areas.

    PubMed

    Fajčíková, K; Cvečková, V; Stewart, A; Rapant, S

    2014-10-01

    We undertook a quantitative estimation of health risks to residents living in the Slovak Republic and exposed to contaminated groundwater (ingestion by adult population) and/or soils (ingestion by adult and child population). Potential risk areas were mapped to give a visual presentation at basic administrative units of the country (municipalities, districts, regions) for easy discussion with policy and decision-makers. The health risk estimates were calculated by US EPA methods, applying threshold values for chronic risk and non-threshold values for cancer risk. The potential health risk was evaluated for As, Ba, Cd, Cu, F, Hg, Mn, NO3 (-), Pb, Sb, Se and Zn for groundwater and As, B, Ba, Be, Cd, Cu, F, Hg, Mn, Mo, Ni, Pb, Sb, Se and Zn for soils. An increased health risk was identified mainly in historical mining areas highly contaminated by geogenic-anthropogenic sources (ore deposit occurrence, mining, metallurgy). Arsenic and antimony were the most significant elements in relation to health risks from groundwater and soil contamination in the Slovak Republic contributing a significant part of total chronic risk levels. Health risk estimation for soil contamination has highlighted the significance of exposure through soil ingestion in children. Increased cancer risks from groundwater and soil contamination by arsenic were noted in several municipalities and districts throughout the country in areas with significantly high arsenic levels in the environment. This approach to health risk estimations and visualization represents a fast, clear and convenient tool for delineation of risk areas at national and local levels. PMID:24729053

  4. Environmental risk assessment of the use of different organic wastes as soil amendments

    NASA Astrophysics Data System (ADS)

    Alvarenga, Paula; Palma, Patrícia; Mourinha, Clarisse; Farto, Márcia; Cunha-Queda, Ana Cristina; Natal-da-Luz, Tiago; Sousa, José Paulo

    2013-04-01

    The use of organic wastes in agriculture is considered a way of maintaining or restoring the quality of soils, enlarging the slow cycling soil organic carbon pool. However, a wide variety of undesired substances, such as potentially trace elements and organic contaminants, can have adverse effects on the environment. That fact was highlighted by the Proposal for a Soil Framework Directive, which recognized that "soil degradation or soil improvements have a major impact on other areas, (…) such as surface waters and groundwater, human health, climate change, protection of nature and biodiversity, and food safety". Taking that into account, the research project "ResOrgRisk" aims to assess the environmental risk involved in the use of different organic wastes as soil amendments, evidencing their benefits and constraints, and defining the most suitable tests to reach such assessment. The organic wastes selected for this purpose were: sewage sludge, limed, not limed, and co-composted with agricultural wastes, agro-industrial sludge, mixed municipal solid waste compost, compost produced from organic farming residues, and pig slurry digestate. Whereas threshold values for heavy metals in sludge used for agriculture have been set by the European Commission, actually there is no definitive European legislation for organic contaminants. Guide values for some organic contaminants (e.g. polychlorinated biphenyls - PCBs, and polycyclic aromatic hydrocarbons - PAHs) have been adopted at national level by many European countries, such as Portugal. These values should be taken into account when assessing the risk involved in the use of organic wastes as soil amendments. However, chemical analysis of organic waste often gives scarce information because it does not include possible interactions between chemicals. Furthermore, an exhaustive identification and quantification of all substances is impractical. In this study, ecotoxicological tests (comprising solid and aquatic phases

  5. Contamination and risk assessment of heavy metals in soils irrigated with biogas slurry: a case study of Taihu basin.

    PubMed

    Bian, Bo; Wu, Hai suo; Zhou, Ling jun

    2015-04-01

    The accumulation of heavy metals in different soils resulting from irrigation with biogas slurry obtained from Taihu basin may create a potential public health risk. We quantified the concentration of heavy metals (Zn, Pb, Cu, Cr, As, and Cd.) in soils. Results indicated that the concentrations of Ni, Zn, Cd, and Pb in soil exceeded the maximum permitted levels set by Chinese Soil Environmental Quality Standard (GB15618-2008). The highest mean level in the soil was noted for Zn, followed by Zn, Pb, Cu, Cr, As, and Cd, while maximum geoaccumulation index (Igeo) was found for Cd in all soil samples which ranged from strongly polluted to extremely polluted. Pollution levels varied with metals and soil types. Moreover, the concentrations of Mn, Co, Ni, Cu, Zn, As, and Pb in soils showed significant correlations with OM; pH showed positive correlations with Cd, Cu, As, and Cr; pH and OM were the most important factors controlling the uptake of heavy metals by soils. Multivariate principal component analysis showed anthropogenic contributions of Zn, Pb, Cu, As, and Cd in the different kinds of soils. The target hazard quotient (HQ) values of six metals in soils were less than 1, which suggested that non-carcinogenic risks of metal exposure to soils were generally assumed to be safe. The assessment results of carcinogenic risks in soils showed higher risks than an acceptable range of 1E-06 to 1E-04 that would pose potential cancer risks to the farmers due to the work of leafy and root vegetables grown locally. PMID:25732981

  6. Soil amendment affects Cd uptake by wheat - are we underestimating the risks from chloride inputs?

    PubMed

    Dahlin, A Sigrun; Eriksson, Jan; Campbell, Colin D; Öborn, Ingrid

    2016-06-01

    Many parts of the world are investigating the efficacy of recycling nutrient resources to agriculture from different industry and domestic sectors as part of a more circular economy. The complex nature of recycled products as soil amendments coupled to the large diversity of soil types and their inherent properties make it difficult to optimize the benefits and minimize the risks from potentially toxic elements often present in recycled materials. Here we investigated how wheat grain cadmium (Cd) concentration was affected by soil amendments, namely human urine and biogas digestate compared to traditional farm manures and mineral fertilizers. We show that Cl(-) inadvertently added to soils with e.g. urine or biogas digestate strongly increased crop Cd concentrations, largely by mobilizing inherent soil Cd. This resulted in wheat grain Cd levels that could result in exceeding recommended WHO limits for dietary intake. This was evident even in soils with low inherent Cd content and when Cd inputs were low. The future of a circular economy that helps to underpin global food security needs to ensure that the effects of applying complex materials to different types of agricultural land are fully understood and do not jeopardize food safety. PMID:26974588

  7. Ecotoxicological and analytical assessment of hydrocarbon-contaminated soils and application to ecological risk assessment

    SciTech Connect

    Saterbak, A.; Toy, R.J.; Wong, D.C.L.; McMain, B.J.; Williams, M.P.; Dorn, P.B.; Brzuzy, L.P.; Chai, E.Y.; Salanitro, J.P.

    1999-07-01

    Ecotoxicological assessments of contaminated soil aim to understand the effect of introduced chemicals on the soil flora and fauna. Ecotoxicity test methods were developed and conducted on hydrocarbon-contaminated soils and on adjacent uncontaminated control soils from eight field locations. Tests included 7-d, 14-d, and chronic survival tests and reproduction assays for the earthworm (Eisenia fetida) and seed germination, root length, and plant growth assays for corn, lettuce, mustard, and wheat. Species-specific responses were observed with no-observed effect concentrations (NOECs) ranging from <1 to 100% contaminated soil. The 14-d earthworm survival NOEC was equal to or greater than the reproduction NOEC values for numbers of cocoons and juveniles, which were similar to one another. Cocoon and juvenile production varied among the control soils. Germination and root length NOECs for mustard and lettuce were less than NOECs for corn and wheat. Root length NOECs were similar to or less than seed germination NOECs. Statistically significant correlations for earthworm survival and seed germination as a function of hydrocarbon measurements were found. The 14-d earthworm survival and the seed germination tests are recommended for use in the context of a risk-based framework for the ecological assessment of contaminated sites.

  8. Risk assessment of human health for geogenic chromium and nickel in soils derived from serpentines

    NASA Astrophysics Data System (ADS)

    Hseu, Zeng-Yei; Lai, Yun-Jie

    2016-04-01

    Concentrations of Cr and Ni are extremely high in serpentine soils compared to soils from the other parent materials. Three serpentine sites in Taiwan were selected to determine health risk of Cr and Ni as cumulative carcinogenic and non-carcinogenic risks via the multiple routes of ingestion, dermal contact, inhalation, and diet on adults and children. The mean levels of Cr and Ni were higher than the soil control standards of heavy metals in Taiwan (250 and 200 mg/kg of Cr and Ni). For adults and children, the total dose of chronic daily intake (mg/kg/d) was the highest for Ni, followed in descending order by Cr(III) and Cr(VI) at all sites. Regardless inhabitant age, the total carcinogenic risk was much lower than 1.0E-6. However, the hazard index (HI) of non-carcinogenic risk exceeded 1.0 for adults at all sites, which was mainly contributed in Ni by eating rice.

  9. PAHs contamination in urban soils from Lisbon: spatial variability and potential risks

    NASA Astrophysics Data System (ADS)

    Cachada, Anabela; Pereira, Ruth; Ferreira da Silva, Eduardo; Duarte, Armando

    2015-04-01

    Polycyclic Aromatic hydrocarbons (PAHs) can become major contaminants in urban and industrial areas, due to the existence of a plethora of diffuse and point sources. Particularly diffuse pollution, which is normally characterized by continuous and long-term emission of contaminants below risk levels, can be a major problem in urban areas. Since PAHs are persistent and tend to accumulate in soils, levels are often above the recommended guidelines indicating that ecological functions of soils may be affected. Moreover, due to the lipophilic nature, hydrophobicity and low chemical and biological degradation rates of PAHs, which leads to their bioconcentration and bioamplification, they may reach toxicological relevant concentrations in organisms. The importance and interest of studying this group of contaminants is magnified due to their carcinogenic, mutagenic and endocrine disrupting effects. In this study, a risk assessment framework has been followed in order to evaluate the potential hazards posed by the presence of PAHs in Lisbon urban soils. Hence, the first step consisted in screening the total concentrations of PAHs followed by the calculation of risks based on existing models. Considering these models several samples were identified as representing a potential risk when comparing with the guidelines for soil protection. Moreover, it was found that for 38% of samples more than 50% of species can be potentially affected by the mixture of PAHs. The use of geostatistical methods allowed to visualize the predicted distribution of PAHs in Lisbon area and identify the areas where possible risk to the environment are likely occurring However, it is known that total concentration may not allow a direct prediction of environmental risk, since in general only a fraction of total concentration is available for partitioning between soil and solution and thus to be uptake or transformed by organisms (bioacessible or bioavailable) or to be leached to groundwater. The

  10. Evaluation of toxicity to the amphipod, Hyalella azteca, and to the midge, Chironomus dilutus; and bioaccumulation by the oligochaete, Lumbriculus variegatus, with exposure to PCB-contaminated sediments from Anniston, Alabama

    USGS Publications Warehouse

    Ingersoll, Christopher G.; Steevens, Jeffery A.; MacDonald, Donald D.; Brumbaugh, William G.; Coady, Matthew R.; Farrar, J. Daniel; Lotufo, Guilherme R.; Kemble, Nile E.; Kunz, James L.; Stanley, Jacob K.; Sinclair, Jesse A.

    2014-01-01

    The U.S. Environmental Protection Agency (USEPA) requested that as part of the remedial investigation for the Anniston, Alabama Polychlorinated Biphenyl (PCB) Site (Anniston PCB Site), that Pharmacia Corporation and Solutia Inc. (P/S) perform long-term reproduction toxicity tests with the amphipod, Hyalella azteca, and the midge, Chironomus dilutus, and bioaccumulation tests with the oligochaete, Lumbriculus variegatus, using sediment samples collected from reference locations and from Operable Unit 4 of the Anniston PCB Site. The sediment toxicity testing and sediment bioaccumulation results will be used by ARCADIS U.S., Inc. (ARCADIS) as part of a weight-of-evidence assessment to evaluate risks and establish sediment remediation goals for contaminants to sediment-dwelling organisms inhabiting the Anniston PCB Site. The goal of this study was to characterize relations between sediment chemistry and sediment toxicity and relations between sediment chemistry and sediment bioaccumulation in samples of sediments collected from the Anniston PCB Site. A total of 32 samples were evaluated from six test sites and one reference site to provide a wide range in concentrations of chemicals of potential concern (COPCs) including PCBs in samples of whole sediment. The goal of this study was not to determine the extent of sediment contamination across the Anniston PCB Site. Hence, the test sites or samples collected from within a test site were not selected to represent the spatial extent of sediment contamination across the Anniston PCB Site. Sediment chemistry, pore-water chemistry, and sediment toxicity data were generated for 26 sediment samples from the Anniston PCB Site. All of the samples were evaluated to determine if they qualified as reference sediment samples. Those samples that met the chemical selection criteria and biological selection criteria were identified as reference samples and used to develop the reference envelope for each toxicity test endpoint. Physical

  11. [Comprehensive Risk Assessment of Soil Heavy Metals Based on Monte Carlo Simulation and Case Study].

    PubMed

    Yang, Yang; Dai, Dan; Cai, Yi-min; Chen, Wei-ping; Hou, Yu; Yang, Feng

    2015-11-01

    Based on the stochastic. theory, the Monte Carlo simulation was introduced in ecological risk assessment and health risk assessment. Together with the multi-statistical technique, the proposed models were used for risk analysis in the Bin-Chang Coal Chemical industry park. The results showed that high levels of Cd, Co, and Cr were found in the area with long time mining. The comprehensive single index and comprehensive risk index showed that the ecological risk of soil metals fell into the poor level, with probabilities of 53.2% and 55.6%, respectively. The health risk caused by hand to mouth ingestion was significantly greater than that by dermal exposure, and Cr was of prime concern for pollution control. Children were taking a major health risk. Their non-cancer risks were maintained at a high level, and 5.0-fold higher than adults under hand to mouth ingestion, and 8.2-fold higher than adults under dermal exposure. The cancer risk for children under these two exposure ways were both above the safety standard suggested by USEPA. PMID:26911013

  12. A comparative study of human health risks via consumption of food crops grown on wastewater irrigated soil (Peshawar) and relatively clean water irrigated soil (lower Dir).

    PubMed

    Jan, F Akbar; Ishaq, M; Khan, S; Ihsanullah, I; Ahmad, I; Shakirullah, M

    2010-07-15

    Food crops irrigated with wastewater are mostly contaminated with heavy metals and considered as a main pathway for human exposure. In this study, soil and food crops samples were collected from wastewater irrigated soils, background and relatively less polluted areas. Results of the sequential extraction and total metals concentrations in soils indicated that wastewater irrigation has significantly increased (p > or = 0.001) the bioavailable and total metal contents in wastewater irrigated soil as compared to background and control soils. Heavy metal concentrations in the food crops grown on wastewater irrigated soil were higher than those grown on background and control soils but were found within WHO/FAO permissible limits except for Zn. Health risk index values were less than 1 for both control and wastewater irrigated soils (except Mn). However, the food crops such as Brassica rapa, Spinacia oleracae L., Lycopersicum esculantum, Mentha viridis, Coriandum sativum and Lactuca sativa grown on wastewater irrigated soil can pose health risks because of the high concentration of Mn. PMID:20399016

  13. A Multi-Sensor Approach for Satellite Soil Moisture Monitoring for Agricultural Climate Risk Assessment

    NASA Astrophysics Data System (ADS)

    Champagne, C.; Cherneski, P.; Hadwen, T. A.; Davidson, A.

    2014-12-01

    Satellite missions specifically dedicated to soil moisture retrieval have become a reality in the past few years, with the launch of SMOS in 2009 and SMAP in 2014. While much of the work on applications around these missions has focussed on data assimilation systems for numerical weather prediction, there is also potential to use the data to support agricultural applications such as drought and flood assessment and yield forecasting. Previous work has examined the potential for using SMOS soil moisture for detecting spatial and temporal patterns of agroclimate risk, such as drought and excess wetness. This research builds upon that work through the examination of a data set with a longer reference period to determine if the dataset can be used as a baseline for detecting anomalies from normal conditions. Surface satellite soil moisture from a multi-sensor climate reference data set (1993 to 2010) and the SMOS surface soil moisture data (2010 - 2014) set were examined in hindsight to detect relevant trends for monitoring the climate conditions in agricultural regions of Canada. Soil moisture and soil moisture anomalies were examined against precipitation and temperature records over the relevant time periods, and compared against agroclimatic drought risk indicators, including the Palmer Drought Severity Index, the Standardized Precipitation Index and the MODIS Normalized Difference Vegetation Condition anomalies. High impact events, including the 2002 drought in the Canadian Prairies, excess wetness in the southern Manitoba in 2009 and 2011 were evaluated in detail. The potential for using these data sets in near real time to support agricultural decision making will be discussed.

  14. Engineered nanomaterials in water and soils: a risk quantification based on probabilistic exposure and effect modeling.

    PubMed

    Gottschalk, Fadri; Kost, Elias; Nowack, Bernd

    2013-06-01

    The production and use of engineered nanomaterials (ENMs) are increasing rapidly, and therefore, the need to assess their environmental exposure and associated risks has become increasingly important. Only a handful of studies have quantified the release and environmental concentrations of ENMs, but much work has been done to investigate the effects of these materials on organisms. The aim of the present study was to quantify probabilistically the environmental risks of ENMs, producing species sensitivity distributions that were then compared with probability distributions of predicted environmental concentrations. Five nanomaterials (nano-Ag, nano-TiO2 , nano-ZnO, carbon nanotubes [CNTs], and fullerenes) and 4 environmental compartments (surface water, sewage treatment plant effluents, soils, and sludge-treated soils) were considered. From 60 ecotoxicological studies, the authors extracted 112 single values to work with (25 values in 13 studies for nano-Ag, 17 values in 10 studies for CNTs, 7 values in 7 studies for fullerenes, 34 values in 23 studies for nano-TiO2 , and 29 values in 17 studies for nano-ZnO). The results indicate there is only a marginal risk for these metal-based nanomaterials in surface water (0.7% risk for nano-Ag and <0.1% for nano-TiO2 ) and some risk in sewage treatment plant effluents (nano-Ag 39.7%, nano-TiO2 18.7%, and nano-ZnO 1.1%). Apart from a marginal value of <0.1% for nano-TiO2 in sludge-treated soils, no risk from the other evaluated ENMs in terrestrial compartments is currently predicted. The discussion of the results considers the influence of the effects of different forms of 1 ENM (coating, agglomeration state, and mineralogy), the test conditions (dissolution and agglomeration), and transformation reactions. PMID:23418073

  15. Indoor Soiling Method and Outdoor Statistical Risk Analysis of Photovoltaic Power Plants

    NASA Astrophysics Data System (ADS)

    Rajasekar, Vidyashree

    This is a two-part thesis. Part 1 presents an approach for working towards the development of a standardized artificial soiling method for laminated photovoltaic (PV) cells or mini-modules. Construction of an artificial chamber to maintain controlled environmental conditions and components/chemicals used in artificial soil formulation is briefly explained. Both poly-Si mini-modules and a single cell mono-Si coupons were soiled and characterization tests such as I-V, reflectance and quantum efficiency (QE) were carried out on both soiled, and cleaned coupons. From the results obtained, poly-Si mini-modules proved to be a good measure of soil uniformity, as any non-uniformity present would not result in a smooth curve during I-V measurements. The challenges faced while executing reflectance and QE characterization tests on poly-Si due to smaller size cells was eliminated on the mono-Si coupons with large cells to obtain highly repeatable measurements. This study indicates that the reflectance measurements between 600-700 nm wavelengths can be used as a direct measure of soil density on the modules. Part 2 determines the most dominant failure modes of field aged PV modules using experimental data obtained in the field and statistical analysis, FMECA (Failure Mode, Effect, and Criticality Analysis). The failure and degradation modes of about 744 poly-Si glass/polymer frameless modules fielded for 18 years under the cold-dry climate of New York was evaluated. Defect chart, degradation rates (both string and module levels) and safety map were generated using the field measured data. A statistical reliability tool, FMECA that uses Risk Priority Number (RPN) is used to determine the dominant failure or degradation modes in the strings and modules by means of ranking and prioritizing the modes. This study on PV power plants considers all the failure and degradation modes from both safety and performance perspectives. The indoor and outdoor soiling studies were jointly

  16. [Spatial distribution and risk assessment of insecticides in surface soil from a rapidly urbanizing region].

    PubMed

    Wei, Yan-Li; Bao, Lian-Jun; Wu, Cheng-Zhou; Zeng, Eddy Y

    2014-10-01

    To examine the distribution patterns of organic contaminants in rapidly urbanizing regions, the levels and spatial distributions of 19 overlooked insecticides, i. e., phenyl-pyrazole class (fipronil), chlordane, endosulfan, nonachlor, hexachlorobenzene, heptachlor, dieldrin, aldrin, endrin, methoxychlor and their metabolites, were examined in 229 soil samples collected from the Pearl River Delta (PRD) and surrounding areas. The results indicated that higher insecticide levels distributed in the central PRD, while lower levels congested in the surrounding areas. The similar spatial patterns between the levels of insecticides and economic prosperity or population density demonstrated that social-economic factors may have dictated the spatial patterns of insecticides. In addition, the changing of land-use types during urbanization processes, e.g., historical plowlands have been converted into residential landscapes, resulted in high concentrations of banned insecticides in metropolis of the central PRD. Source diagnostics indicated that new inputs of technical chlordane products existed in the PRD and surrounding areas. Fipronil was degraded into fipronil sulfone and fipronil sulfide in most soil samples because of its low half-life in soil. Finally, a risk assessment of 19 insecticides in soil for human health suggested that six samples collected from the major administrative districts with dense population had potential cancer or non-cancer risk to human health. Therefore, these overlooked insecticides should be concerned in future environmental research. PMID:25693389

  17. [Risk assessment and countermeasures of BTEX contamination in soils of typical pesticide factory].

    PubMed

    Tan, Bing; Wang, Tie-Yu; Li, Qi-Feng; Zhang, Hai-Yan; Pang, Bo; Zhu, Zhao-Yun; Wang, Dao-Han; Lü, Yong-Long

    2014-06-01

    Soil samples around three representative pesticide factories were collected in Zhangjiakou City, Hebei Province, and analyzed to identify their pollution characteristics and health risk of BTEX by purge-and trap and gas chromatography/mass spectroscopy method. Total concentrations of BTEX in soils in Plant A, B and C ranged from 673.50 to 32 363.50 ng x g(-1), nd to 6 461.80 ng x g(-1) and 461.70 to 8 740.80 ng x g(-1), respectively. Concentrations of detected toluene (4 619.50-7 234.30 ng x g(-1)) and ethylbenzene (364.60-7 944.60 ng x g(-1)) had exceeded the Canadian guidelines for industrial land (370 ng x g(-1) and 82 ng x g(-1)), and concentration of xylene (19 799.40 ng x g(-1)) in dust in production area of Plant A was larger than the Dutch soil intervention value (17 000 ng x g(-1)). While concentrationsn of BTEX around Plant A (Region I ) and Plant B and C (Region II) ranged from nd to 645.81 ng x g(-1), and nd to 309.13 ng x g(-1), respectively, which were below the Canadian guidelines for agricultural land. The non-carcinogenic risk of BTEX in Plant A (2.90E-06 -1.32E-04), B (nd -4.30E-05) and C (1.29E-06 -5.64E-05) were all below 1, which suggested that no obvious health risk existed in each plant. The non-carcinogenic risks in Region I (nd -2.02E-06) and Region II (nd -1.10E-06) were below than 1, and also lower than those in factories. High risk areas were mainly concentrated in the downwind, moreover, soils around villages and towns were also with higher risk. In conclusion, soils and dusts in each factory had been polluted and the quality of agricultural land had been partly deteriorated. Finally, environmental management and occupational protection countermeasures were proposed based on the research results. PMID:25158506

  18. Temporal trends toward stability of Hudson River PCB contamination

    SciTech Connect

    Sloan, R.J.; Simpson, K.W.; Schroeder, R.A.; Barnes, C.R.

    1983-10-01

    PCB was used in the manufacture of electrical equipment at two General Electric Company (GE) facilities located on the upper Hudson River about 1 km apart in Fort Edward and Hudson Falls (Washington Co.) New York. Discharges of PCB from these plants resulted in concentrations in bottom sediments of the Hudson River which now exceed those of other major rivers by about two orders of magnitude and those of small remote streams by more than three orders of magnitude. Intensive monitoring was initiated in 1977 by the New York State Department of Environmental Conservation (DEC) to ascertain the magnitude of and trends in contaminant conditions of biotic and physical strata. The paper summarizes PCB trends from 1977 to 1981 in three major monitoring components - water, multiplate residues and fish.

  19. Recovery of a PCB-Contaminated Creek Fish Community

    EPA Science Inventory

    Polychlorinated Biphenyls (PCBs) from the Sangamo-Weston Superfund Site near Clemson, South Carolina, USA, were released into the Twelvemile Creek until the early 1990s. PCB concentrations in fish in this creek have remained elevated: levels in six target fish species are still a...

  20. INFECUNDITY AND CONSUMPTION OF PCB-CONTAMINATED SPORT FISH

    EPA Science Inventory

    Biologic capacity for reproduction, or fecundity, may be threatened by environmental contaminants, especially compounds capable of disrupting endocrine pathways. Telephone interviews that focused on reproductive events were conducted with female members of the New York State Angl...

  1. Risks and benefits of gardening in urban soil; heavy metals and nutrient content in Los Angeles Community Gardens

    NASA Astrophysics Data System (ADS)

    Clarke, L. W.; Jenerette, D.; Bain, D. J.

    2012-12-01

    The availability of soil nutrients and heavy metals in urban community gardens can influence health of crops and participants. Interactions between garden history, management, and soils are understudied in cities. In July 2011, we collected soil samples from 45 plots at 6 Los Angeles community gardens. For comparison, 3 samples were collected from uncultivated garden soils and 3 more from outside soils. Samples were then tested for major nutrients- Nitrogen(N), Potassium (K), and Phosphorous (P)- and organic matter (SOM). We also measured concentrations of 29 metals in 3 gardens using Inductively Coupled Plasma- Atomic Emission Spectroscopy. Potassium and phosphorus exceeded optimum levels in all plots, with some over twice the maximum recommended levels. Over-fertilized soils may contribute to local watershed pollution and crop micronutrient deficiencies. Low soil SOM was observed in gardens in impoverished neighborhoods, possibly due to low quality amendments. Our metals analysis showed dangerous levels of lead (Pb)-- up to 1700 ppm in outside soils and 150 ppm in garden soils-- near older gardens, indicating lead deposition legacies. California lead safety standards indicate that children should not play near soils with Pb above 200 ppm, indicating need for long term monitoring of lead contaminated gardens. Arsenic (As) levels exceeded federal risk levels (0.3 ppm) and average CA background levels (2 ppm) in all areas, with some gardens exceeding 10 ppm. Heavy metal legacies in gardens may pose risks to participants with prolonged exposure and remediation of soils may be necessary.

  2. [Distribution and Risk Assessment of Sulfonamides Antibiotics in Soil and Vegetables from Feedlot Livestock].

    PubMed

    Jin, Cai-xia; Si, Xiao-wei; Wang, Zi-ying; Zhang, Qin-wen

    2016-04-15

    Soil and vegetable samples were collected from 13 different livestock farms of different sizes in Xinxiang of China, and the residues of three sulfonamides including sulfadiazine, sulfamonomethoxine, and sulfamethoxazole were analyzed by HPLC with a fluorimetric detector, The results indicated that the total concentration ranges of the three sulfonamides in soil and vegetable were 7.60-176.26 µg · kg⁻¹ and ND-32, 70 µg · kg⁻¹, respectively. The mean concentrations were 70.73 µg · kg⁻¹ and 7.08 µg · kg⁻¹ for soil and vegetables. The residue levels in soil were all lower than the ecotoxic effect trigger value (100 µg · kg⁻¹) set by the Veterinary Medicine International Coordination Commission, indicating the low risk for organisms in soil. The concentrations of three sulfonamides varied significantly in different kinds of vegetables and were all lower than the acceptable daily intake values [50 µg · (kg ·d)⁻¹] set by Joint FAO/WHO Expert CommIttee on Food Additives. But we cannot neglect the potential ecotoxicity and resistance for human via food chain. PMID:27548983

  3. Soil factors of ecosystems' disturbance risk reduction under the impact of rocket fuel

    NASA Astrophysics Data System (ADS)

    Krechetov, Pavel; Koroleva, Tatyana; Sharapova, Anna; Chernitsova, Olga

    2016-04-01

    Environmental impacts occur at all stages of space rocket launch. One of the most dangerous consequences of a missile launch is pollution by components of rocket fuels ((unsymmetrical dimethylhydrazine (UDMH)). The areas subjected to falls of the used stages of carrier rockets launched from the Baikonur cosmodrome occupy thousands of square kilometers of different natural landscapes: from dry steppes of Kazakhstan to the taiga of West Siberia and mountains of the Altai-Sayany region. The study aims at assessing the environmental risk of adverse effects of rocket fuel on the soil. Experimental studies have been performed on soil and rock samples with specified parameters of the material composition. The effect of organic matter, acid-base properties, particle size distribution, and mineralogy on the decrease in the concentration of UDMH in equilibrium solutions has been studied. It has been found that the soil factors are arranged in the following series according to the effect on UDMH mobility: acid-base properties > organic matter content >clay fraction mineralogy > particle size distribution. The estimation of the rate of self-purification of contaminated soil is carried out. Experimental study of the behavior of UDMH in soil allowed to define a model for calculating critical loads of UDMH in terrestrial ecosystems.

  4. Assessment of the human health risks posed by exposure to chromium-contaminated soils

    SciTech Connect

    Sheehan, P.J.; Meyer, D.M.; Sauer, M.M.; Paustenbach, D.J. )

    1991-02-01

    Millions of tons of chromite-ore processing residue have been used as fill in various locations in northern New Jersey and elsewhere in the United States. The primary toxicants in the residue are trivalent chromium (Cr(III)) and hexavalent chromium (Cr(VI)). The hazard posed by Cr(III) is negligible due to its low acute and chronic toxicity. In contrast, Cr(VI) is a human carcinogen following inhalation of high concentrations. It can also cause allergic contact dermatitis. This evaluation addresses a residential site where the arithmetic mean (x) and geometric mean (gm) concentrations of Cr(III) in soil were 2879 and 1212 mg/kg (ppm). The mean concentrations of Cr(VI) were 180 and 4 mg/kg, respectively. The uptake (absorbed dose) of Cr(III) via soil ingestion, consumption of homegrown vegetables, and ingestion of inspired particles was determined. The uptake of Cr(VI) via dermal absorption from contact with surface soil and building wall surfaces, as well as inhalation, was also evaluated. The techniques used in this assessment are applicable for evaluating the human health risks posed by any residential site having contaminated soil. The potential for both sensitized and unsensitized persons to develop allergic contact dermatitis due to exposure to soil contaminated at these levels was found to be negligible. The estimated average daily dose (ADD) via ingestion and dermal absorption for the maximally exposed individual (MEI) was about 1500- and 40-fold below the EPA reference dose (RfD) for Cr(III) and Cr(VI), respectively. It was shown that for residential sites, the most important route of exposure to Cr(III) was incidental soil ingestion. Although not relevant to these sites specifically, if garden vegetables could be successfully grown in these soils, then they would probably be the predominant source of uptake of Cr(III). 163 refs.

  5. A Framework for Establishment of a Risk Assessment Model for Soil Erosion by Integrating the AHP Approach and Modeling Techniques

    NASA Astrophysics Data System (ADS)

    Wang, M.; Wu, Q.

    2006-12-01

    A new approach for establishment of an analytical risk assessment model to evaluate the risk index for soil erosion is proposed in which the analytical hierarchy process (AHP) approach and the model calibration and validation processes are integrated. A flowchart presenting a general procedure for implementation of the proposed approach is included. A case study is presented to demonstrate applications of this proposed framework through investigation of soil erosion by water in a joining area that partially covers the Shanxi province, Shaanxi province, and Inner Mongolia Autonomous Region of China. Based on field survey and information analyses, pertinent factors for soil erosion by water in this region are assessed and nine dominating factors are identified. The dominating factors considered include the soil type, rainstorm intensity, landform accounting for physiognomy type, ravine density, and land slope, vegetation coverage, mining area, level of water and soil conservation, and type of land uses. The GIS thematic layers of degrees of risk on soil erosion for those dominating factors are constructed. The weight of each thematic layer is determined through the AHP approach and modeling techniques. This model is then applied in predicting development of soil erosion at a typical scenario for this study area. A brief discussion on construction and application of this model is presented. It is demonstrated that the presented methodology is practicable for establishing a risk assessment mode for soil erosion by water for an area of interest where pertinent information such as remote sensing data is available. Furthermore, a predictive soil erosion model established by the proposed approach may be implemented for investigations of other pertinent environmental issues such as relative and quantitative risk assessments of migration of absorbed contaminants in soil, resulted from agricultural non-point source pollution, into a river or lake through soil erosion.

  6. Assessment of herbicide leaching risk in two tropical soils of Reunion Island (France).

    PubMed

    Bernard, H; Chabalier, P F; Chopart, J L; Legube, B; Vauclin, M

    2005-01-01

    Application of organic chemicals to a newly irrigated sugarcane (Saccharum officinarum L.) area located in the semiarid western part of Reunion Island has prompted local regulatory agencies to determine their potential to contaminate ground water resources. For that purpose, simple indices known as the ground water ubiquity score (Gustafson index, GUS), the retardation factor (RF), the attenuation factor (AF), and the log-transformed attenuation factor (AFT) were employed to assess the potential leaching of five herbicides in two soil types. The herbicides were alachlor [2-chloro-2',6'-diethyl-N-(methoxy-methy) acetanilide], atrazine [2-chloro-4-(ethylamino)-6-(isopropylamino)-1,3,5-triazine], diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea], 2,4-D [(2,4-dichlorophenoxy) acetic-acid], and triclopyr [((3,5,6-trichloro-2-pyridyl)oxy) acetic-acid]. The soil types were Vertic (BV) and Andepts (BA) Inceptisols, which are present throughout the Saint-Gilles study area on Reunion Island. To calculate the indices, herbicide sorption (K(oc)) and dissipation (half-life, DT50) properties were determined from controlled batch experiments. Water fluxes below the root zone were estimated by a capacity-based model driven by a rainfall frequency analysis performed on a 13-yr data series. The results show a lower risk of herbicide leaching than in temperate regions due to the tropical conditions of the study area. Higher temperatures and the presence of highly adsorbent soils may explain smaller DT50 and higher K(oc) values than those reported in literature concerning temperate environments. Based on the RF values, only 2,4-D and triclopyr appear mobile in the BV soil, with all the other herbicides being classified from moderately to very immobile in both soils. The AFT values indicate that the potential leaching of the five herbicides can be considered as unlikely, except during the cyclonic period (about 40 d/yr) when there is a 2.5% probability of recharge rates equal to or

  7. Levels and ecological risk assessment of metals in soils from a typical e-waste recycling region in southeast China.

    PubMed

    Zhao, Weituo; Ding, Lei; Gu, Xiaowen; Luo, Jie; Liu, Yunlang; Guo, Li; Shi, Yi; Huang, Ting; Cheng, Shenggao

    2015-11-01

    Due to the high threat to human health and the ecosystem from metals, the levels and distribution of As, Hg, Cr, Co, Ni, Cu, Zn, Cd, Pb, Mn, V, Sn, Sb, Li and Be in various layers of soil from an e-waste recycling area in Guiyu, China were investigated. The extent of pollution from the metals in soil was assessed using enrichment factors (EFs) and the Nemerow pollution index (P N ). To determine the metals' integrated potential ecological risks, the potential ecological risk index (RI) was chosen. The concentrations of Hg, Ni, Cu, Cd, Pb, Sn and Sb were mainly enriched in the topsoil. EF values (2-5) of the elements Hg, Co, Ni, Zn, Sn, Li and Be revealed their moderate enrichment status in the topsoil, derived from e-waste recycling activities. P N presented a decreasing trend in different layers in the order topsoil (0-20 cm) > deep soil (100-150 cm) > middle soil (50-100 cm) > shallow soil (20-50 cm). With higher potential ecological risk factor (E(i)), Hg and Cd are the main contributors to the potential ecological risk. With respect to the RI, all the values in soil from the study area exceeded 300, especially for the soil at sites S2, S4, S5, S7 and S8, where RI was greater than 600. Therefore, immediate remediation of the contaminated soil is necessary to prevent the release of metals and potential ecological harm. PMID:26318052

  8. A methodology for estimating risks associated with landslides of contaminated soil into rivers.

    PubMed

    Göransson, Gunnel; Norrman, Jenny; Larson, Magnus; Alén, Claes; Rosén, Lars

    2014-02-15

    Urban areas adjacent to surface water are exposed to soil movements such as erosion and slope failures (landslides). A landslide is a potential mechanism for mobilisation and spreading of pollutants. This mechanism is in general not included in environmental risk assessments for contaminated sites, and the consequences associated with contamination in the soil are typically not considered in landslide risk assessments. This study suggests a methodology to estimate the environmental risks associated with landslides in contaminated sites adjacent to rivers. The methodology is probabilistic and allows for datasets with large uncertainties and the use of expert judgements, providing quantitative estimates of probabilities for defined failures. The approach is illustrated by a case study along the river Göta Älv, Sweden, where failures are defined and probabilities for those failures are estimated. Failures are defined from a pollution perspective and in terms of exceeding environmental quality standards (EQSs) and acceptable contaminant loads. Models are then suggested to estimate probabilities of these failures. A landslide analysis is carried out to assess landslide probabilities based on data from a recent landslide risk classification study along the river Göta Älv. The suggested methodology is meant to be a supplement to either landslide risk assessment (LRA) or environmental risk assessment (ERA), providing quantitative estimates of the risks associated with landslide in contaminated sites. The proposed methodology can also act as a basis for communication and discussion, thereby contributing to intersectoral management solutions. From the case study it was found that the defined failures are governed primarily by the probability of a landslide occurring. The overall probabilities for failure are low; however, if a landslide occurs the probabilities of exceeding EQS are high and the probability of having at least a 10% increase in the contamination load

  9. Occurrence, sources and health risk assessment of polycyclic aromatic hydrocarbons in urban (Pudong) and suburban soils from Shanghai in China.

    PubMed

    Wang, Xue-Tong; Chen, Lei; Wang, Xi-Kui; Lei, Bing-Li; Sun, Yan-Feng; Zhou, Jun; Wu, Ming-Hong

    2015-01-01

    A comprehensive investigation was conducted to the urban (Pudong) and suburban soils in Shanghai. A total of 154 soil samples were analyzed for 26 PAHs including highly carcinogenic dibenzopyrenes (DBPs). The total concentrations ranged from 25.8 to 7380 μg kg(-1) for Σ26PAHs and 18.8 to 6320 μg kg(-1) for 16 USEPA priority PAHs (Σ16PAHs), respectively. The BaP toxic equivalent (BaPeq) concentrations were between 6.41 and 2880 μg kg(-1) for Σ24PAHs, 1.11 and 620 μg kg(-1) for Σ16PAHs and 2.72 and 2250 μg kg(-1) for Σ4DBPs. The high PAH contamination in green land soils might originate mainly from local road traffic and industrial activities, and sewage sludge application or waste water irrigation for soil. Seven sources of soil PAHs in Shanghai were identified by positive matrix factorization (PMF) model. The mean risk quotient (m-RQ) values indicated that there were medium to high ecological risks in 9.10% of soil samples, pyrene (Pyr), benzo[b]fluoranthene (BbF) and benz[a]anthracene (BaA) were the major ecological risk drivers under agricultural use. The cancer risk (CR) values were within the acceptable range at 35.7%, 35.1% and 31.2% of sampling sites for children, youths and adults, respectively. The total lifetime carcinogenic risk (TLCR) values at 57.8% of sampling sites were within the acceptable range. Overall, cancer risks of soil PAHs in all sampling sites in the studied area were below the highest acceptable risk, suggesting that soil PAHs are unlikely to pose a significant cancer risk for population based on ingestion, dermal contact and inhalation exposure pathways. PMID:25460765

  10. Ecogeochemical mapping of urban soils as a tool for indication of risk factors

    NASA Astrophysics Data System (ADS)

    Sahakyan, Lilit; Saghetalyan, Armen; Asmaryan, Shushanik

    2010-05-01

    Today, most global and local environmental issues are connected with the disturbance of natural equilibrium of chemical elements, which is manifested by two contrary but synchronous and interconnected geochemical processes: dispersion and concentration of chemical elements. The ecological consequence of those intensively running processes is pollution of environmental compartments. High intensity and multi-component character of pollution is common to urban ecosystems. In this respect emphasized should be mining centers representing biogeochemical provinces where the whole range of geochemical processes connected with socio-economic activities of the man reaches its maximum and high natural background of chemical elements is coupled with their man-made load. Ecogeochemical mapping of soils of mining regions and cities is one of major tools while assessing ecological state of the territory and indicating risk factors. When systemizing indices of geochemical pollution, the produced case specific maps coupled with ecogeochemical mapping techniques are territorial generalization of levels of pollution and levels of its danger. This allows indicating its spatial differentiation and finally ranging the city's territory by features of the defined level of ecological risk. Moreover, ecogeochemical mapping of soils allows indicating dominating pollutants, peculiarities of their distribution and major risk factors as well and thus revealing risk groups in the population. An alternative method of ecogeochemical mapping of urban soils which allows to notably reduce the process of pollution level assessment and identification of risk factor is that of remote sensing. Collation between spatially conjugated data of soil analyses and multi-zonal satellite images allows developing spectral characteristics (signatures) of pollution of the territory with heavy metals (HM) and development of appropriate assessment criteria which may be reflected as diverse case specific maps. This

  11. [Heavy metal pollution characteristics and ecological risk analysis for soil in Phyllostachys praecox stands of Lin'an].

    PubMed

    Fang, Xiao-bo; Shi, Han; Liao, Xin-feng; Lou, Zhong; Zhou, Lyu-yan; Yu, Hai-xia; Yao, Lin; Sun, Li-ping

    2015-06-01

    An investigation was carried out in an attempt to reveal the characteristics of heavy metals contamination in the soils of Phyllostachys praecox forest in Lin' an. Based on the concentrations of Hg, As, Cu, Pb, Zn, Cd, Cr, Ni, Co and Mn in 160 topsoil samples, the pollution status and ecological risks of heavy metals in the soils were assessed by single factor pollution index, Nemerow integrated pollution index and Hankanson potential ecological risk index. The spatial variability of heavy metal concentrations in the soils closely related to the distribution of traffic, industrial and livestock pollution sources. The average concentrations of Hg, As, Cu, Pb, Zn, Cd, Cr, Ni, Co and Mn in the soils were 0.16, 7.41, 34.36, 87.98, 103.98, 0.26, 59.12, 29.56, 11.44 and 350.26 mg · kg(-1), respectively. Pb, Cd, Zn and Cu concentrations were as 2.89, 1.70, 1.12 and 1.12 times as the background values of soil in Zhejiang Province, respectively. But their concentrations were all lower than the threshold values of the National Environmental Quality Standard for Soil (GB 15618-1995). The average single factor pollution index revealed that the level of heavy metal pollution in the soils was in order of Pb>Cd>Cu= Zn>Hg>As>Ni>Co>Cr>Mn. Pb pollution was of moderate level while Cd, Cu and Zn pollutions were slight. There was no soil pollution caused by the other heavy metals. However, the Nemerow integrated pollution index showed that all the 160 soil samples were contaminated by heavy metals to a certain extent. Among total 160 soil samples, slight pollution level, moderate pollution level and heavy pollution level accounted for 55.6%, 29.4% and 15.0%, respectively. The average single factor potential ecological risk index (Er(i)) implied that the potential ecological risk related to Cd reached moderate level, while the others were of slight level. Furthermore, Cd and Hg showed higher potential ecological risk indices which reached up to 256.82 and 187.33 respectively

  12. Contamination and risk of heavy metals in soils and sediments from a typical plastic waste recycling area in North China.

    PubMed

    Tang, Zhenwu; Zhang, Lianzhen; Huang, Qifei; Yang, Yufei; Nie, Zhiqiang; Cheng, Jiali; Yang, Jun; Wang, Yuwen; Chai, Miao

    2015-12-01

    Plastic wastes are increasingly being recycled in many countries. However, available information on the metals released into the environment during recycling processes is rare. In this study, the contamination features and risks of eight heavy metals in soils and sediments were investigated in Wen'an, a typical plastic recycling area in North China. The surface soils and sediments have suffered from moderate to high metal pollution and in particular, high Cd and Hg pollution. The mean concentrations of Cd and Hg were 0.355 and 0.408 mg kg(-1), respectively, in the soils and 1.53 and 2.10 mg kg(-1), respectively, in the sediments. The findings suggested that there is considerable to high potential ecological risks in more than half of the soils and high potential ecological risk in almost all sediments. Although the health risk levels from exposure to soil metals were acceptable for adults, the non-carcinogenic risks to local children exceeded the acceptable level. Source assessment indicated that heavy metals in soils and sediments were mainly derived from inputs from poorly controlled plastic waste recycling operations in this area. The results suggested that the risks associated with heavy metal pollution from plastic waste recycling should be of great concern. PMID:26318969

  13. Soil heavy metal dynamics and risk assessment under long-term land use and cultivation conversion.

    PubMed

    Wang, Xuelei; Xu, Yiming

    2015-01-01

    Long-term agricultural development and cultivation conversions affect soil heavy metal balance and the regional environmental safety. In this study, heavy metal parameters were used to identify changes in soil properties in response to land use and cultivation conversions. The integrated soil quality index, which involves seven heavy metal indices, was proposed to assess the environmental risk of long-term human activities in Northeast China. We used the remote sensing and geographical data for the four-term land use distribution from 1979 to 2009 to identify the spatial patterns of regional land use conversions. Then, 41 samples from the top 20 cm of the soil at sites corresponding to these seven types of conversions were collected (permanent dry land, dry land converted from wetland, dry land converted from forest, permanent wetland, permanent forest, paddy land converted from dry land, and paddy land converted from wetland). Based on the local soil properties and tillage practices, the following seven heavy metal parameters were employed: Arsenic (As), Cadmium (Cd), Chromium (Cr), Copper (Cu), Nickel (Ni), Lead (Pb), and Zinc (Zn). The conversion of farmland from wetland resulted in an increase in the concentration of Pb and Cr in the soil. In contrast, the concentrations of Zn, Cu, Ni, and Cd decreased when wetland was converted into farmland because the tillage practices washed these heavy metals away. During the conversion of dry land and paddy land to wetland, the levels of Pb increased by approximately 28.6% and 24.7%, respectively. Under the same conditions, the concentration of As increased by 32.5% and 14.1%, respectively. The integrated index also demonstrated that the farmlands were not contaminated by the heavy metals during long-term agricultural development. PMID:25060313

  14. Polycyclic aromatic hydrocarbons in soils from the Central-Himalaya region: Distribution, sources, and risks to humans and wildlife.

    PubMed

    Bi, Xiang; Luo, Wei; Gao, Jiajia; Xu, Lan; Guo, Junming; Zhang, Qianggong; Romesh, Kumar Y; Giesy, John P; Kang, Shichang; de Boer, Jacob

    2016-06-15

    The Central Himalayas are not only a natural boundary between China and Nepal but also a natural barrier for transport of air masses from South Asia. In this study, 99 samples of surface soil were collected from five regions of Nepal on the southern side of the Central Himalayas, and 65 samples of surface soil were obtained from the northern side on the edge of the Tibetan Plateau, China (TPC). Concentrations of polycyclic aromatic hydrocarbons (PAHs) in soils were measured to determine their distribution, potential for accumulation, and sources, as well as risks to humans and the environment. Mean concentrations of Σ16PAHs were 2.4×10(2) and 3.3×10(2)ng/g dry mass (dm) in soils collected from the TPC and Nepal, respectively. Significant correlations between concentrations of lower molecular weight PAHs (LMW-PAHs) in soils and altitude were found. Total organic carbon (TOC) in soil was positively but weakly correlated with concentrations of PAHs in the study area, which suggested little role of TOC in adsorption of PAHs. The cities of Kathmandu and Pokhara in Nepal and Nyemo (especially Zhangmu Port), Shigatse, and Lhasa on the TPC, were areas with relatively great concentrations of PAHs in soils. The main sources of PAHs identified by positive matrix factorization were emissions from motor vehicles and combustion of coal and biomass in the Central Himalayas. Calculated total benzo[a]pyrene potency equivalents of 0.23-44ng/gdm and index of additive cancer risk of 3.8×10(-3)-9.2×10(-1) indicated that PAHs in almost all soils investigated posed de minimis risk of additional cancer to residents via direct contact and had no significant risk of additional cancers through consumption of potable water. Mean risk quotient values indicated that 39% of soils had a slight risk to wildlife and the ambient environment of the Central Himalayas. PMID:26971206

  15. Operational methods for minimising soil compaction and diffuse pollution risk from wheelings in winter cereals

    NASA Astrophysics Data System (ADS)

    Jackson, Bob; Silgram, Martyn; Quinton, John

    2010-05-01

    Recent UK government-funded research has shown that compacted, unvegetated tramlines wheelings can represent an important source and transport pathway, which can account for 80% of surface runoff, sediment and phosphorus losses to edge-of-field from cereals on moderate slopes. For example, recent research found 5.5-15.8% of rainfall lost as runoff, and losses of 0.8-2.9 kg TP/ha and 0.3-4.8 T/ha sediment from tramline wheelings. When compaction was released by shallow cultivation, runoff was reduced to 0.2-1.7% of rainfall with losses of 0.0-0.2 kg TP/ha and 0.003-0.3 T/ha sediment respectively i.e. close to reference losses from control areas without tramlines. Recent independent assessments using novel tracer techniques have also shown that tramline wheelings can represent important sediment sources at river catchment scale. In response to these latest findings, a new project is now underway investigating the most cost-effective and practical ways of operationalising methods for managing tramline wheelings in autumn-sown cereal systems to reduce the risk of soil compaction from the autumn spray operation and the associated risk of surface runoff and diffuse pollution loss of sediment, phosphorus and nitrogen to edge of field. Research is focusing on the over-winter period when soils are close to field capacity and the physical protection of the soil surface granted by growing crop is limited. This paper outlines this new multi-disciplinary project and associated methodologies, which include hillslope-scale event-based evaluations of the effectiveness of novel mitigation methods on surface runoff and diffuse pollution losses to edge of field, assessments of the economic and practical viability of mitigation methods, and modelling the impact on water quality of implementation of the most promising techniques at both farm and catchment scale. The study involves a large consortium with 20 partners, including many industrial organisations representing tractor, crop

  16. Concentrations, distribution, sources and risk assessment of organohalogenated contaminants in soils from Kenya, Eastern Africa.

    PubMed

    Sun, Hongwei; Qi, Yueling; Zhang, Di; Li, Qing X; Wang, Jun

    2016-02-01

    The organohalogenated contaminants (OCs) including 12 organochlorine pesticides (OCPs), 7 indicator polychlorinated biphenyls (PCBs) and 7 polybrominated diphenyl ethers (PBDEs) were determined in soils collected from Kenya, Eastern Africa. The total OCPs fell in the range of n.d-49.74 μg kg(-1) dry weight (dw), which was dominated by DDTs and endosulfan. Identification of pollution sources indicated new input of DDTs for malaria control in Kenya. The total PCBs ranged from n.d. to 55.49 μg kg(-1) dw, dominated by penta- and hexa-PCBs, probably associated with the leakage of obsolete transformer oil. The soils were less contaminated by PBDEs, ranging from 0.19 to 35.64 μg kg(-1) dw. The predominant PBDE congeners were penta-, tri- or tetra-BDEs, varying among different sampling sites. Risk assessment indicated potential human health risks posed by OCs in soils from Kenya, with PCBs as the most contributing pollutants. The local authorities are recommended to make best efforts on management of OC pollution, particularly from DDTs and PCBs to meet the requirement of Stockholm Convention. PMID:26686059

  17. Ecological risk assessment of heavy metals in soils surrounding oil waste disposal areas.

    PubMed

    Xu, Jianling; Wang, Hanxi; Liu, Yuanyuan; Ma, Mengchao; Zhang, Tian; Zheng, Xiaoxue; Zong, Meihan

    2016-02-01

    More attention is being devoted to heavy metal pollution because heavy metals can concentrate in higher animals through the food chain, harm human health and threaten the stability of the ecological environment. In this study, the effects of heavy metals (Cu, Cr, Zn, Pb, Cd, Ni and Hg) emanating from oil waste disposal on surrounding soil in Jilin Province, China, were investigated. A potential ecological risk index was used to evaluate the damage of heavy metals and concluded that the degree of potential ecological damage of heavy metals can be ranked as follows: Hg > Cd > Pb > Cu > Ni > Cr > Zn. The average value of the potential ecological harm index (Ri) is 71.93, thereby indicating light pollution. In addition, this study researched the spatial distribution of soil heavy metals by means of ArcGIS (geographic information system) spatial analysis software. The results showed that the potential ecological risk index (R) of the large value was close to the distance from the oil waste disposal area; it is relatively between the degree of heavy metals in soil and the distance from the waste disposal area. PMID:26832722

  18. Assessing risk to human health from tropical leafy vegetables grown on contaminated urban soils.

    PubMed

    Nabulo, G; Young, S D; Black, C R

    2010-10-15

    Fifteen tropical leafy vegetable types were sampled from farmers' gardens situated on nine contaminated sites used to grow vegetables for commercial or subsistence consumption in and around Kampala City, Uganda. Trace metal concentrations in soils were highly variable and originated from irrigation with wastewater, effluent discharge from industry and dumping of solid waste. Metal concentrations in the edible shoots of vegetables also differed greatly between, and within, sites. Gynandropsis gynandra consistently accumulated the highest Cd, Pb and Cu concentrations, while Amaranthus dubius accumulated the highest Zn concentration. Cadmium uptake from soils with contrasting sources and severity of contamination was consistently lowest in Cucurbita maxima and Vigna unguiculata, suggesting these species were most able to restrict Cd uptake from contaminated soil. Concentrations of Pb and Cr were consistently greater in unwashed, than in washed, vegetables, in marked contrast to Cd, Ni and Zn. The risk to human health, expressed as a 'hazard quotient' (HQ(M)), was generally greatest for Cd, followed successively by Pb, Zn, Ni and Cu. Nevertheless, it was apparent that urban cultivation of leafy vegetables could be safely pursued on most sites, subject to site-specific assessment of soil metal burden, judicious choice of vegetable types and adoption of washing in clean water prior to cooking. PMID:20739044

  19. Assessment and optimization of an ultrasound-assisted washing process using organic solvents for polychlorinated biphenyl-contaminated soil.

    PubMed

    Bezama, Alberto; Flores, Alejandra; Araneda, Alberto; Barra, Ricardo; Pereira, Eduardo; Hernández, Víctor; Moya, Heriberto; Konrad, Odorico; Quiroz, Roberto

    2013-10-01

    The goal of this work was to evaluate a washing process that uses organic solutions for polychlorinated biphenyl (PCB)-contaminated soil, and includes an ultrasound pre-treatment step to reduce operational times and organic solvent losses. In a preliminary trial, the suitability of 10 washing solutions of different polarities were tested, from which three n-hexane-based solutions were selected for further evaluation. A second set of experiments was designed using a three-level Taguchi L27 orthogonal array to model the desorption processes of seven different PCB congeners in terms of the variability of their PCB concentration levels, polarity of the washing solution, sonication time, the ratio washing solution/soil, number of extraction steps and total washing time. Linear models were developed for the desorption processes of all congeners. These models provide a good fit with the results obtained. Moreover, statistically significant outcomes were achieved from the analysis of variance tests carried out. It was determined that sonication time and ratio of washing solution/soil were the most influential process parameters. For this reason they were studied in a third set of experiments, constructed as a full factorial design. The process was eventually optimized, achieving desorption rates of more than 90% for all congeners, thus obtaining concentrations lower than 5 ppb in all cases. The use of an ultrasound-assisted soil washing process for PCB-contaminated soils that uses organic solvents seems therefore to be a viable option, especially with the incorporation of an extra step in the sonication process relating to temperature control, which is intended to prevent the loss of the lighter congeners. PMID:23771880

  20. Assessing the risk of N leaching from forest soils across a steep N deposition gradient in Sweden.

    PubMed

    Akselsson, Cecilia; Belyazid, Salim; Hellsten, Sofie; Klarqvist, Malin; Pihl-Karlsson, Gunilla; Karlsson, Per-Erik; Lundin, Lars

    2010-12-01

    Nitrogen leaching from boreal and temporal forests, where normally most of the nitrogen is retained, has the potential to increase acidification of soil and water and eutrophication of the Baltic Sea. In parts of Sweden, where the nitrogen deposition has been intermediate to high during recent decades, there are indications that the soils are close to nitrogen saturation. In this study, four different approaches were used to assess the risk of nitrogen leaching from forest soils in different parts of Sweden. Nitrate concentrations in soil water and C:N ratios in the humus layer where interpreted, together with model results from mass balance calculations and detailed dynamic modelling. All four approaches pointed at a risk of nitrogen leaching from forest soils in southern Sweden. However, there was a substantial variation on a local scale. Basing the assessment on four different approaches makes the assessment robust. PMID:20864233

  1. Ecotoxicological hazard and risk assessment of heavy metal contents in agricultural soils of central Germany.

    PubMed

    Manz, M; Weissflog, L; Kühne, R; Schürmann, G

    1999-02-01

    Heavy metal content of agricultural topsoils has been experimentally determined at 14 areas in the German Leipzig-Halle-Bitterfeld region covering ca. 3700 km2. For most of the locations and elements, the contamination levels are comparable to those of other agricultural sites in Germany and Europe. Application of a sequential extraction technique revealed relatively low contamination levels in the mobile fractions, which indicates a correspondingly low degree of bioavailability of the heavy metals under the current milieu conditions. In contrast, acidification of the soil due to a drastic decrease in the deposition of calciferous fly ash would lead to a significantly increased ecotoxicological hazard potential, as is analyzed by a probabilistic distribution method that quantifies the overlap of normalized exposure and effect data. The discussion includes recommendations for further improvement of risk assessment schemes addressing soil contamination. PMID:10051370

  2. Source identification and health risk assessment of metals in urban soils around the Tanggu chemical industrial district, Tianjin, China.

    PubMed

    Zhao, Long; Xu, Yafei; Hou, Hong; Shangguan, Yuxian; Li, Fasheng

    2014-01-15

    We conducted an investigation to identify the sources of metals in urban surface soils, and to assess the associated human health risks, around the Tanggu chemical industrial district, Tianjin, China. The metal concentrations and spatial distributions in 70 soil samples from the study area were determined. Pollution sources were identified using multivariate statistical analysis. They mainly attributed Cu, Pb, and Zn pollution to vehicular traffic and industrial discharges, Cd pollution to industrial activities and anthropogenic waste including industrial discharges, sewage sludge, and municipal solid waste, As and Hg pollution to coal combustion and point source emissions from the chemical industry, and Cr and Ni pollution to the soil parent material. Soil properties, particularly the organic matter content, were found to be important factors in the distribution and composition of metals. A health risk assessment showed that samples from the northwestern and southeastern parts of the study area may pose significant health risks to the population. PMID:24061056

  3. Health risks of heavy metals in contaminated soils and food crops irrigated with wastewater in Beijing, China.

    PubMed

    Khan, S; Cao, Q; Zheng, Y M; Huang, Y Z; Zhu, Y G

    2008-04-01

    Consumption of food crops contaminated with heavy metals is a major food chain route for human exposure. We studied the health risks of heavy metals in contaminated food crops irrigated with wastewater. Results indicate that there is a substantial buildup of heavy metals in wastewater-irrigated soils, collected from Beijing, China. Heavy metal concentrations in plants grown in wastewater-irrigated soils were significantly higher (Psoil, and exceeded the permissible limits set by the State Environmental Protection Administration (SEPA) in China and the World Health Organization (WHO). Furthermore, this study highlights that both adults and children consuming food crops grown in wastewater-irrigated soils ingest significant amount of the metals studied. However, health risk index values of less than 1 indicate a relative absence of health risks associated with the ingestion of contaminated vegetables. PMID:17720286

  4. Distribution, bioavailability, and potential ecological risk of Cu, Pb, and Zn in soil in a potential groundwater source area.

    PubMed

    Teng, Yanguo; Feng, Dan; Wu, Jin; Zuo, Rui; Song, Liuting; Wang, Jinsheng

    2015-05-01

    In this study, we examined three horizontal and vertical soil profiles along a sewage drainage ditch in order to determine the spatial distribution of Cu, Pb, and Zn in soils and to assess the bioavailability and potential ecological risks associated with these metals in a potential groundwater source area. Results showed that the concentrations of Cu, Pb, and Zn were approximately at background level, suggesting that human activities (industrial and agricultural pollution) had a negligible influence on these metals in soil, and that the concentrations reflected the natural background levels in the study area. Cu, Pb, and Zn concentrations were slightly higher in topsoil (0-20 cm) than deeper in the soil profile. Using a modified BCR sequential extraction method to evaluate the mobility and bioavailability of metals showed that the potential bioavailability sequence of Cu, Pb, and Zn at three depths in the soil profile was in the order Cu ≈ Pb < Zn. The potential ecological risk from the metals was evaluated using risk assessment code, and the results suggest that Cu and Zn pose no or low risk, while there is a low or medium risk from Pb. Results from groundwater monitoring showed that the groundwater was not polluted by leaching from soil. PMID:25910722

  5. Human Health Risks Associated with Metals from Urban Soil and Road Dust in an Oilfield Area of Southeastern Algeria.

    PubMed

    Benhaddya, Mohammed Lamine; Boukhelkhal, Abdelaziz; Halis, Youcef; Hadjel, Mohammed

    2016-04-01

    Hassi Messaoud town is a recent city that is situated inside the oil field, which hosts an important petroleum extraction field and refinery. Large-scale and long-term oil refinery and corresponding industrial activities may contaminate the surrounding soil/dust and could lead to pollution levels that can affect human health. The soil and road dust samples were analysed for different trace elements: copper (Cu), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn). Geo-accumulation index (I(geo)), pollution index (PI), and integrated pollution index (IPI) were calculated to evaluate the heavy metal contamination level of urban soil and road dust. The I(geo) values indicate unpolluted to moderate polluted of investigated metals in the soil samples. The assessment results of PI support the results of I(geo), and IPI indicates heavy metals in road dust polluted seriously. The noncarcinogenic health risk assessment shows that ingestion of soil/dust particles is the route for exposure to heavy metals, followed by dermal adsorption. The human exposure risk assessment based on different exposure pathways showed that the hazard index (HI) was <1.0 for all of the elements. The relative exposure risk (noncarcinogenic) was greater for toddlers. Although the overall risk was within the acceptable limit of 1.00, the HI of Pb from the soil (0.103) and road dust (0.132) was close to the threshold limits, which over the long-term may pose a health risk. PMID:26626598

  6. Heavy metals in apple orchard soils and fruits and their health risks in Liaodong Peninsula, Northeast China.

    PubMed

    Wang, Quanying; Liu, Jingshuang; Cheng, Shuai

    2015-01-01

    This study aimed to assess the heavy metal concentrations in soils and fruits and their possible human health risk in apple orchards of Liaodong Peninsula-a well-known fruit-producing area of China. The soil pollution index (PI) and health risk assessment methods (daily intake of metals (DIM) and health risk index (HRI)) were employed to explore the soil pollution levels and the potential health hazards of heavy metals in fruits. The results showed that all orchard soils were with low PI values (PI ≤1) for Cd and Zn, while 2.78 and 5.56% of the soil samples exceeded the allowable levels of Cr and Cu for orchard soil, respectively. The Cd, Cu, and Zn concentrations for the apple flesh samples were all lower than the national maximum permissible concentrations. While 6.34% of apple peel samples for Cd, 76.5% of apple peel samples and 65.6% of apple flesh samples for Cr, and 28.1% of apple peel samples for Zn exceeded the national maximum permissible levels, respectively. Furthermore, both the DIM and the HRI values for all the apple flesh samples were within the safe limits, indicating that no health risk was found for heavy metals in the fruits of the study area. In order to protect the consumers from fruits that might cause health risks, results from this study suggested that the regular survey of heavy metal pollution levels should be conducted for the orchards of Liaodong Peninsula. PMID:25433544

  7. The Distribution and Health Risk Assessment of Metals in Soils in the Vicinity of Industrial Sites in Dongguan, China.

    PubMed

    Liu, Chao; Lu, Liwen; Huang, Ting; Huang, Yalin; Ding, Lei; Zhao, Weituo

    2016-01-01

    Exponential industrialization and rapid urbanization have resulted in contamination of soil by metals from anthropogenic sources in Dongguan, China. The aims of this research were to determine the concentration and distribution of various metals (arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), nickel (Ni), lead (Pb) and zinc (Zn)) in soils and identify their potential health risks for local residents. A total of 106 soil samples were collected from the vicinity of industrial sites in Dongguan. Two types of samples were collected from each site: topsoil (0-20 cm, TS) and shallow soil (20-50 cm, SS). Results showed that the soils were contaminated by metals and pollution was mainly focused on TS. The geoaccumulation index (Igeo) and pollution indexes (PI) implied that there was a slight increase in the concentrations of Cd, Cu, Hg, Ni, and Pb, but the metal pollution caused by industrial activities was less severe, and elements of As and Cr exhibited non-pollution level. The risk assessment results suggested that there was a potential health risk associated with As and Cr exposure for residents because the carcinogenic risks of As and Cr via corresponding exposure pathways exceeded the safety limit of 10(-6) (the acceptable level of carcinogenic risk for humans). Furthermore, oral ingestion and inhalation of soil particles are the main exposure pathways for As and Cr to enter the human body. This study may provide basic information of metal pollution control and human health protection in the vicinity of industrial regions. PMID:27548198

  8. The Distribution and Health Risk Assessment of Metals in Soils in the Vicinity of Industrial Sites in Dongguan, China

    PubMed Central

    Liu, Chao; Lu, Liwen; Huang, Ting; Huang, Yalin; Ding, Lei; Zhao, Weituo

    2016-01-01

    Exponential industrialization and rapid urbanization have resulted in contamination of soil by metals from anthropogenic sources in Dongguan, China. The aims of this research were to determine the concentration and distribution of various metals (arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), nickel (Ni), lead (Pb) and zinc (Zn)) in soils and identify their potential health risks for local residents. A total of 106 soil samples were collected from the vicinity of industrial sites in Dongguan. Two types of samples were collected from each site: topsoil (0–20 cm, TS) and shallow soil (20–50 cm, SS). Results showed that the soils were contaminated by metals and pollution was mainly focused on TS. The geoaccumulation index (Igeo) and pollution indexes (PI) implied that there was a slight increase in the concentrations of Cd, Cu, Hg, Ni, and Pb, but the metal pollution caused by industrial activities was less severe, and elements of As and Cr exhibited non-pollution level. The risk assessment results suggested that there was a potential health risk associated with As and Cr exposure for residents because the carcinogenic risks of As and Cr via corresponding exposure pathways exceeded the safety limit of 10−6 (the acceptable level of carcinogenic risk for humans). Furthermore, oral ingestion and inhalation of soil particles are the main exposure pathways for As and Cr to enter the human body. This study may provide basic information of metal pollution control and human health protection in the vicinity of industrial regions. PMID:27548198

  9. Occurrence and risk assessment of phthalate esters (PAEs) in vegetables and soils of suburban plastic film greenhouses.

    PubMed

    Wang, Jun; Chen, Gangcai; Christie, Peter; Zhang, Manyun; Luo, Yongming; Teng, Ying

    2015-08-01

    Phthalate esters (PAEs) are suspected of having adverse effects on human health and have been frequently detected in soils and vegetables. The present study investigated their occurrence and composition in plastic film greenhouse soil-vegetable systems and assessed their potential health risks to farmers exposed to these widespread pollutants. Six priority control phthalates, namely dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DnBP), butyl benzyl phthalate (BBP), di-(2-ethylhexyl) phthalate (DEHP) and di-n-octyl phthalate (DnOP), were determined in 44 plastic film greenhouse vegetables and corresponding soils. Total PAEs ranged from 0.51 to 7.16mgkg(-1) in vegetables and 0.40 to 6.20mgkg(-1) in soils with average concentrations of 2.56 and 2.23mgkg(-1), respectively. DnBP, DEHP and DnOP contributed more than 90% of the total PAEs in both vegetables and soils but the proportions of DnBP and DnOP in vegetables were significantly (p<0.05) higher than in soils. The average concentrations of PAEs in pot herb mustard, celery and lettuce were >3.00mgkg(-1) but were <2.50mgkg(-1) in the corresponding soils. Stem and leaf vegetables accumulated more PAEs. There were no clear relationships between vegetable and soil PAEs. Risk assessment indicates that DnBP, DEHP and DnOP exhibited elevated non-cancer risk with values of 0.039, 0.338 and 0.038, respectively. The carcinogenic risk of DEHP was about 3.94×10(-5) to farmers working in plastic film greenhouses. Health risks were mainly by exposure through vegetable consumption and soil ingestion. PMID:25863503

  10. Reducing the Geothermal Exploration Risk by Carbon Dioxide Soil Flux Investigations

    NASA Astrophysics Data System (ADS)

    Carapezza, Maria Luisa; Barberi, Franco; Ranaldi, Massimo; Ricci, Tullio; Tarchini, Luca; De Simone, Gabriele; Gattuso, Alessandro; Silvestri, Mario

    2013-04-01

    In the exploration of medium to high enthalpy geothermal resources it happens rather frequently that deep wells find high temperatures but are not productive because they don't cross any permeable fractured reservoir. Because of the high cost of deep drillings, this aspect represents one of the main economic risks of geothermal exploration. A detailed survey of diffuse CO2 soil flux may allow to identify from the surface the permeable portions of a deep-seated actively degassing geothermal reservoir, drastically reducing this risk. In order to test the effectiveness of CO2 soil flux as a geothermal exploration tool we selected two volcanic areas north of Rome, Latera caldera and Marta zone near lake Bolsena, both hosting a geothermal reservoir with T>200 °C and where productive and non-productive wells had been drilled in the past. We proved that in both zones productive wells are located on high CO2 soil flux zones, whereas the not-productive wells are sited on low flux areas. In addition the surveys allowed to identify some as yet unexplored portions of the geothermal reservoirs where future wells should be conveniently located. Use of the same technique in the medium enthalpy geothermal system of Torre Alfina, Central Italy (T=140°C) showed that the presence of a thick impervious rock cover may be very effective in preventing gas leakages from the reservoir to the surface. Promising results have been obtained also by CO2 soil flux surveys in some geothermal areas of Honduras (Platanares, Azacualpa) and Costa Rica (Las Pailas). Obviously, CO2 flux cannot provide any estimate of temperature at depth, which has to be assessed with other geochemical or geophysical exploration techniques.

  11. Can Physiological Endpoints Improve the Sensitivity of Assays with Plants in the Risk Assessment of Contaminated Soils?

    PubMed Central

    Gavina, Ana; Antunes, Sara C.; Pinto, Glória; Claro, Maria Teresa; Santos, Conceição; Gonçalves, Fernando; Pereira, Ruth

    2013-01-01

    Site-specific risk assessment of contaminated areas indicates prior areas for intervention, and provides helpful information for risk managers. This study was conducted in the Ervedosa mine area (Bragança, Portugal), where both underground and open pit exploration of tin and arsenic minerals were performed for about one century (1857 – 1969). We aimed at obtaining ecotoxicological information with terrestrial and aquatic plant species to integrate in the risk assessment of this mine area. Further we also intended to evaluate if the assessment of other parameters, in standard assays with terrestrial plants, can improve the identification of phytotoxic soils. For this purpose, soil samples were collected on 16 sampling sites distributed along four transects, defined within the mine area, and in one reference site. General soil physical and chemical parameters, total and extractable metal contents were analyzed. Assays were performed for soil elutriates and for the whole soil matrix following standard guidelines for growth inhibition assay with Lemna minor and emergence and seedling growth assay with Zea mays. At the end of the Z. mays assay, relative water content, membrane permeability, leaf area, content of photosynthetic pigments (chlorophylls and carotenoids), malondialdehyde levels, proline content, and chlorophyll fluorescence (Fv/Fm and ΦPSII) parameters were evaluated. In general, the soils near the exploration area revealed high levels of Al, Mn, Fe and Cu. Almost all the soils from transepts C, D and F presented total concentrations of arsenic well above soils screening benchmark values available. Elutriates of several soils from sampling sites near the exploration and ore treatment areas were toxic to L. minor, suggesting that the retention function of these soils was seriously compromised. In Z. mays assay, plant performance parameters (other than those recommended by standard protocols), allowed the identification of more phytotoxic soils. The

  12. Upscaling spatially heterogeneous parameterisations of soil compaction to investigate catchment scale flood risk.

    NASA Astrophysics Data System (ADS)

    Coates, Victoria; Pattison, Ian

    2016-04-01

    Upscaling land management signals observed at the point scale to the regional scale is challenging for three reasons. Individual catchments are unique and at the point scale land management signals are spatially and temporally variable, depending on topography, soil characteristics and on the individual characteristics of a rainfall event. However at larger scales land management effects diffuse and climatic or human induced signals have a larger impact. This does not mean that there is no influence on river flows, just that the effect is not discernible. Land management practices in different areas of the catchment vary spatially and temporally and their influence on the flood hydrograph will be different at different points within the catchment. Once the water enters the river, the land management effects are disturbed further by hydrodynamic and geomorphological dispersion. Pastoral agriculture is the dominant rural land cover in the UK (40% is classified as improved/ semi-natural grassland - Land Cover Map 2007). The intensification of agriculture has resulted in greater levels of soil compaction associated with higher stocking densities in fields. Natural flood management is the alteration, restoration or use of landscape features to reduce flood risk. Soil compaction has been shown to change the partitioning of rainfall into runoff. However the link between locally observed hydrological changes and catchment scale flood risk has not yet been proven. This paper presents the results of a hydrological modelling study on the impact of soil compaction on downstream flood risk. Field experiments have been conducted in multiple fields in the River Skell catchment, in Yorkshire, UK (area of 120km2) to determine soil characteristics and compaction levels under different types of land-use. We use this data to parameterise and validate the Distributed Physically-based Connectivity of Runoff model. A number of compaction scenarios have been tested that represent

  13. Degradation and environmental risk of surfactants after the application of compost sludge to the soil

    SciTech Connect

    Gonzalez, M.M.; Martin, J.; Camacho-Munoz, D.; Santos, J.L.; Aparicio, I.

    2012-07-15

    Highlights: Black-Right-Pointing-Pointer Degradation of surfactants in soil amended with sewage sludge during 100 days. Black-Right-Pointing-Pointer Temperature influences on the degradation of the studied compounds. Black-Right-Pointing-Pointer Overall, the LAS degradation is faster than the NP compounds degradation. Black-Right-Pointing-Pointer Therefore, the LAS presented lower environmental risk than the NP compounds. - Abstract: In this work, the degradation of anionic and non-ionic surfactants in agricultural soil amended with sewage sludge is reported. The compounds analysed were: linear alkylbenzene sulphonates (LAS) with a 10-13 carbon alkylic chain, and nonylphenolic compounds (NPE), including nonylphenol (NP) and nonylphenol ethoxylates with one and two ethoxy groups (NP1EO and NP2EO). The degradation studies were carried out under winter (12.7 Degree-Sign C) and summer (22.4 Degree-Sign C) conditions in Andalusia region. The concentration of LAS was reduced to 2% of the initial concentration 100 day after sludge-application to the soil. The half-life time measured for LAS homologues were ranged between 4 and 14 days at 12.7 Degree-Sign C and between 4 and 7 days at 22.4 Degree-Sign C. With regard to NPE compounds, after 8 and 4 days from the beginning of the experiment at 12.7 and 22.4 Degree-Sign C, respectively, their concentration levels were increased to 6.5 and 13.5 mg/kg dm (dry matter) as consequence of the degradation of nonylphenol polyethoxylates. These concentration levels were reduced to 5% after 63 and 70 days for 12.7 Degree-Sign C and 22.4 Degree-Sign C, respectively. The half-life times measured for NPEs were from 8 to 16 days at 12.7 Degree-Sign C and from 8 to 18 days at 22.4 Degree-Sign C. Environmental risk assessment revealed that for LAS homologues no environment risk could be expected after 7 and 8 days of sludge application to the soil for 22.4 and 12.7 Degree-Sign C, respectively; however, potential toxic effects could be

  14. [Accumulation of Mercury in Soil-maize System of Non-ferrous Metals Smelting Area and Its Related Risk Assessment].

    PubMed

    Ji, Xiao-feng; Zheng, Na; Wang, Yang; Liu, Qiang; Zhang, Jing-jing

    2015-10-01

    Soil heavy metal pollution, especially the mercury pollution, has been widespread concern in non-ferrous metallurgical area. This study focused on the content, distribution and pollution status of Hg in maize soil of Huludao city. Meanwhile, Hg contents in the various organs of maize were analyzed. Hg concentration in soil ranged from 0.25 to 3.49 mg x kg(-1) with the average content of 1.78 mg x kg(-1), which was 48 times as high as the background value of Liaoning soil. Around 2-3m range of zinc plant, the pattern of spatial distribution showed that the content of Hg was gradually increased with the increase of the distance to Huludao zinc plant. The result of geoaccumulation index reflected that Hg pollution is up to moderate pollution level on the whole. 54. 6% of the total sample were belonged to the serious pollution level. The potential ecological risk index of Hakanson was applied to assess the ecological risk of Hg. The target hazard quotient method (THQ) was used to assess the health risk for human, the results revealed that there was no significant health risk by consumption corn. Mercury is very difficult to transport in soil-maize system, and there is no obvious health risks to adults. But the risk coefficient of children, which is up to 0.056. is much higher than adults. PMID:26841621

  15. Hazardous organic compounds in biogas plant end products--soil burden and risk to food safety.

    PubMed

    Suominen, K; Verta, M; Marttinen, S

    2014-09-01

    The end products (digestate, solid fraction of the digestate, liquid fraction of the digestate) of ten biogas production lines in Finland were analyzed for ten hazardous organic compounds or compound groups: polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), polychlorinated biphenyls (PCB(7)), polyaromatic hydrocarbons (PAH(16)), bis-(2-ethylhexyl) phthalate (DEHP), perfluorinated alkyl compounds (PFCs), linear alkylbenzene sulfonates (LASs), nonylphenols and nonylphenol ethoxylates (NP+NPEOs), polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD) and tetrabromobisphenol A (TBBPA). Biogas plant feedstocks were divided into six groups: municipal sewage sludge, municipal biowaste, fat, food industry by-products, animal manure and others (consisting of milling by-products (husk) and raw former foodstuffs of animal origin from the retail trade). There was no clear connection between the origin of the feedstocks of a plant and the concentrations of hazardous organic compounds in the digestate. For PCDD/Fs and for DEHP, the median soil burden of the compound after a single addition of digestate was similar to the annual atmospheric deposition of the compound or compound group in Finland or other Nordic countries. For PFCs, the median soil burden was somewhat lower than the atmospheric deposition in Finland or Sweden. For NP+NPEOs, the soil burden was somewhat higher than the atmospheric deposition in Denmark. The median soil burden of PBDEs was 400 to 1000 times higher than the PBDE air deposition in Finland or in Sweden. With PBDEs, PFCs and HBCD, the impact of the use of end products should be a focus of further research. Highly persistent compounds, such as PBDE- and PFC-compounds may accumulate in agricultural soil after repeated use of organic fertilizers containing these compounds. For other compounds included in this study, agricultural use of biogas plant end products is unlikely to cause risk to food safety in Finland. PMID:24593894

  16. Potential ecological risk assessment and prediction of soil heavy metal pollution around coal gangue dump

    NASA Astrophysics Data System (ADS)

    Jiang, X.; Lu, W. X.; Yang, Q. C.; Yang, Z. P.

    2014-03-01

    Aim of the present study is to evaluate the potential ecological risk and predict the trend of soil heavy metal pollution around a~coal gangue dump in Jilin Province (Northeast China). The concentrations of Cd, Pb, Cu, Cr and Zn were monitored by inductively coupled plasma mass spectrometry (ICP-MS). The potential ecological risk index method developed by Hakanson (1980) was employed to assess the potential risk of heavy metal pollution. The potential ecological risk in an order of E(Cd) > E(Pb) > E(Cu) > E(Cr) > E(Zn) have been obtained, which showed that Cd was the most important factor led to risk. Based on the Cd pollution history, the cumulative acceleration and cumulative rate of Cd were estimated, and the fixed number of years exceeding standard prediction model was established, which was used to predict the pollution trend of Cd under the accelerated accumulation mode and the uniform mode. Pearson correlation analysis and correspondence analysis are employed to identify the sources of heavy metal, and the relationship between sampling points and variables. These findings provide some useful insights for making appropriate management strategies to prevent and decrease heavy metal pollution around coal gangue dump in Yangcaogou coal mine and other similar areas elsewhere.

  17. Potential ecological risk assessment and prediction of soil heavy-metal pollution around coal gangue dump

    NASA Astrophysics Data System (ADS)

    Jiang, X.; Lu, W. X.; Zhao, H. Q.; Yang, Q. C.; Yang, Z. P.

    2014-06-01

    The aim of the present study is to evaluate the potential ecological risk and trend of soil heavy-metal pollution around a coal gangue dump in Jilin Province (Northeast China). The concentrations of Cd, Pb, Cu, Cr and Zn were monitored by inductively coupled plasma mass spectrometry (ICP-MS). The potential ecological risk index method developed by Hakanson (1980) was employed to assess the potential risk of heavy-metal pollution. The potential ecological risk in the order of ER(Cd) > ER(Pb) > ER(Cu) > ER(Cr) > ER(Zn) have been obtained, which showed that Cd was the most important factor leading to risk. Based on the Cd pollution history, the cumulative acceleration and cumulative rate of Cd were estimated, then the fixed number of years exceeding the standard prediction model was established, which was used to predict the pollution trend of Cd under the accelerated accumulation mode and the uniform mode. Pearson correlation analysis and correspondence analysis are employed to identify the sources of heavy metals and the relationship between sampling points and variables. These findings provided some useful insights for making appropriate management strategies to prevent or decrease heavy-metal pollution around a coal gangue dump in the Yangcaogou coal mine and other similar areas elsewhere.

  18. APPLICATION OF CHEMICALLY ACCELERATED BIOTREATMENT TO REDUCE RISK IN OIL-IMPACTED SOILS

    SciTech Connect

    J.R. Paterek; W.W. Bogan; L.M. Lahner; A. May

    2000-04-01

    The overall program objective is to develop and evaluate integrated biological/physical/chemical co-treatment strategies for the remediation of wastes associated with the exploration and production of fossil energy. The specific objectives of this project are: chemical accelerated biotreatment (CAB) technology development for enhanced site remediation, application of the risk based analyses to define and support the rationale for environmental acceptable endpoints (EAE) for exploration and production wastes, and evaluate both the technological technologies in conjugation for effective remediation of hydrocarbon contaminated soils from E&P sites in the USA.

  19. Application of Chemically Accelerated Biotreatment to Reduce Risk in Oil-Impacted Soils

    SciTech Connect

    Paterek, J.R.; Bogan, W.W.; Sirivedhin; Tanita

    2003-03-06

    Research was conducted in six major focus areas: (1) Evaluation of the process using 6 test soils with full chemical and physical characteristics to determine controlling factors for biodegradation and chemical oxidation; (2) Determination of the sequestration time on chemical treatment suspectability; (3) Risk factors, i.e. toxicity after chemical and biological treatment; (4) Impact of chemical treatment (Fenton's Reagent) on the agents of biodegradation; (5) Description of a new genus and its type species that degrades hydrocarbons; and (6) Intermediates generate from Fenton's reagent treatment of various polynuclear aromatic hydrocarbons.

  20. APPLICATION OF CHEMICALLY ACCELERATED BIOTREATMENT TO REDUCE RISK IN OIL-IMPACTED SOILS

    SciTech Connect

    J.R. Paterek; W.W. Bogan; L.M. Lahner; V. Trbovic; E. Korach

    2001-05-01

    The overall program objective is to develop and evaluate integrated biological/physical/chemical co-treatment strategies for the remediation of wastes associated with the exploration and production of fossil energy. The specific objectives of this project are: chemical accelerated biotreatment (CAB) technology development for enhanced site remediation, application of the risk based analyses to define and support the rationale for environmental acceptable endpoints (EAE) for exploration and production wastes, and evaluate both the technological technologies in conjugation for effective remediation of hydrocarbon contaminated soils from E&P sites in the USA.

  1. Subsoil compaction in Flanders: from soil map to susceptibility map and risk map for subsoil compaction

    NASA Astrophysics Data System (ADS)

    van de Vreken, Philippe; van Holm, Lieven; Diels, Jan; van Orshoven, Jos

    2010-05-01

    assigned the PCS-value calculated for pF 2.5 or the PCS-value calculated for pF 1.8, based on a decision rule. This rule was based on the expected depth of the groundwater table in spring, from which we calculated the expected pF-value at 40 cm of depth. Then, for each soil map unit this calculated pF was compared to pF 2.5, respectively pF 1.8 in order to determine the closest of the two pF-values and the corresponding PCS-value. Based on the developed susceptibility maps so called ‘risk maps' were constructed which show the modeled maximum allowable wheel load that may be exerted on the surface of each soil map unit by either (i) a 480/80R42 tractor tyre or (ii) a 800/65R32 tyre of a sugarbeet harvester in order not to exceed the estimated ‘pre-compaction PCS' at 40 cm of depth. Therefore we calculated the normal stresses generated by those tyres on the 40 cm reference depth, by making use of the analytical soil compaction model SoilFlex (Keller et al., 2007). Based on the results of a parallel study (Van Holm et al., 2010) in which different soil compaction related parameters were measured on subsoil samples (40 cm) of 17 arable fields, belonging to different soil textural classes and distributed all over Flanders, we could conclude that a severe compaction of subsoil material has taken place since the period 1950-1970 as the PCS-values determined in 2009 for those fields (by uniaxial compaction tests and the Casagrande method; Casagrande, 1936) were always (much) higher then the PCS-values retrieved for the same soil map units from the inherent susceptibility map (= historical map) for the same depth. Knowledge about actual soil bulk density is an important key to actualise the developed maps.

  2. Contribution for tier 1 of the ecological risk assessment of Cunha Baixa uranium mine (Central Portugal): I soil chemical characterization.

    PubMed

    Pereira, R; Antunes, S C; Marques, S M; Gonçalves, F

    2008-02-15

    Within the tier 1 of a site specific risk assessment, the pseudo-total concentrations (extracted with aqua regia) and the potential mobile fractions of metals were determined to perform a preliminary evaluation of risks posed by contaminated soils from an abandoned uranium mine (Mangualde, Central Portugal). Considering the mobile fractions of metals, extracted with artificial rain water, aluminium and uranium were the most concerning elements, since their concentrations were above soil quality criteria values (SQGVs) established for both elements. However, according to the evaluation based on potential mobile fractions of elements, rather than on pseudo-total metal concentrations the risks were limited to sites within the exploitation area, where contamination derives mainly from past in-situ leaching activities of pore ore as well as from the deposition of sludge from the effluent pond. The exclusion of other sites under evaluation, from the risk assessment process, requires additional data provided by soil screening ecotoxicological assays. PMID:17919686

  3. Estimating potential risks to terrestrial invertebrates and plants exposed to bisphenol A in soil amended with activated sludge biosolids.

    PubMed

    Staples, Charles; Friederich, Urs; Hall, Tilghman; Klecka, Gary; Mihaich, Ellen; Ortego, Lisa; Caspers, Norbert; Hentges, Steven

    2010-02-01

    Bisphenol A (BPA) is a high production volume substance primarily used to produce polycarbonate plastic and epoxy resins. During manufacture and use, BPA may enter wastewater treatment plants. During treatment, BPA may become adsorbed to activated sludge biosolids, which may expose soil organisms to BPA if added to soil as an amendment. To evaluate potential risks to organisms that make up the base of the terrestrial food web (i.e., invertebrates and plants) in accordance with international regulatory practice, toxicity tests were conducted with potworms (Enchytraeids) and springtails (Collembolans) in artificial soil, and six plant types using natural soil. No-observed-effect concentrations (NOEC) for potworms and springtails were equal to or greater than 100 and equal to or greater than 500 mg/kg (dry wt), respectively. The lowest organic matter-normalized NOEC among all tests (dry shoot weight of tomatoes) was 37 mg/kg-dry weight. Dividing by an assessment factor of 10, a predicted-no-effect concentration in soil (PNEC(soil)) of 3.7 mg/kg-dry weight was calculated. Following international regulatory guidance, BPA concentrations in soil hypothetically amended with biosolids were calculated using published BPA concentrations in biosolids. The upper 95th percentile BPA biosolids concentration in North America is 14.2 mg/kg-dry weight, and in Europe is 95 mg/kg-dry weight. Based on recommended biosolids application rates, predicted BPA concentrations in soil (PEC(soil)) would be 0.021 mg/kg-dry weight for North America and 0.14 mg/kg-dry weight for Europe. Hazard quotients (ratio of PEC(soil) and PNEC(soil)) for BPA were all equal to or less than 0.04. This indicates that risks to representative invertebrates and plants at the base of the terrestrial food web are low if exposed to BPA in soil amended with activated sludge biosolids. PMID:20821466

  4. Distribution of environmentally sensitive elements in residential soils near a coal-fired power plant: potential risks to ecology and children's health.

    PubMed

    Tang, Quan; Liu, Guijian; Zhou, Chuncai; Zhang, Hong; Sun, Ruoyu

    2013-11-01

    One hundred and twelve soil samples were collected from residential areas surrounding a coal-fired power plant at Huainan City, Anhui Province, China. The concentrations of environmentally sensitive elements (ESEs As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, V and Zn) in soil samples were determined, and their potential ecological and health risks were assessed. Mean concentrations of ESEs in the downwind soils of the power plant are relatively higher than those in the upwind soils, pointing to a potential ESEs input from coal combustion. The calculated ecological risk of ESEs in soils indicates a relatively low ecological risk. Hazard quotient (HQ) of ESEs in downwind soils is 1.5, suggesting a potential health risk for children. However, the carcinogenic risk values of ESEs in soils are within the acceptable non-hazardous range of 1E-06-1E-04. PMID:24091246

  5. Field dissipation and risk assessment of typical personal care products TCC, TCS, AHTN and HHCB in biosolid-amended soils.

    PubMed

    Chen, Feng; Ying, Guang-Guo; Ma, Yi-Bing; Chen, Zhi-Feng; Lai, Hua-Jie; Peng, Feng-Jiao

    2014-02-01

    The antimicrobial agents triclocarban (TCC) and triclosan (TCS) and synthetic musks AHTN (Tonalide) and HHCB (Galaxolide) are widely used in many personal care products. These compounds may release into the soil environment through biosolid application to agricultural land and potentially affect soil organisms. This paper aimed to investigate accumulation, dissipation and potential risks of TCC, TCS, AHTN and HHCB in biosolid-amended soils of the three field trial sites (Zhejiang, Hunan and Shandong) with three treatments (CK: control without biosolid application, T1: single biosolid application, T2: repeated biosolid application every year). The one-year monitoring results showed that biosolids application could lead to accumulation of these four chemicals in the biosolid-amended soils, with the residual concentrations in the following order: TCC>TCS>AHTN>HHCB. Dissipation of TCC, TCS, AHTN and HHCB in the biosolid-amended soils followed the first-order kinetics model. Half-lives for TCC, TCS, AHTN and HHCB under the field conditions of Shandong site were 191, 258, 336 and 900 days for T1, and 51, 106, 159 and 83 days for T2, respectively. Repeated applications of biosolid led to accumulation of these personal care products and result in higher ecological risks. Based on the residual levels in the trial sites and limited toxicity data, high risks to soil organisms are expected for TCC and TCS, while low-medium risks for AHTN and HHCB. PMID:24239829

  6. Mobility and eco-risk of trace metals in soils at the Hailuogou Glacier foreland in eastern Tibetan Plateau.

    PubMed

    Bing, Haijian; Wu, Yanhong; Zhou, Jun; Liang, Jianhong; Wang, Jipeng; Yang, Zijiang

    2016-03-01

    The concentrations and fractions of cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) in soils collected from Hailuogou Glacier foreland in eastern Tibetan Plateau were analyzed to decipher their mobility, and their eco-risk was assessed combined with multiple environmental indices. The concentrations of Cd were more than ten times higher than its local background in the O horizon and nearly three times higher in the A horizon. The concentrations of Pb and Zn were relatively high in the O horizon, whereas that of Cu increased with soil depth. The main fractions of metals in the surface horizons were reducible and acid-soluble for Cd, oxidizable and residual for Cu, reducible and oxidizable for Pb, and reducible and residual for Zn. The metal mobility generally followed the order of Cd > Pb > Zn > Cu in the O horizon and Cd > Pb > Cu > Zn in the A horizon. Sorption and complexation by soil organic matters imparted an important effect on the mobilization and transformation of Cd, Pb, and Zn in the soils. The oxidizable Cu fraction in the soils showed significant correlation with organic matters, and soil pH mainly modulated the acid-soluble and reducible Cu fractions. The concentrations and other environmental indices including contamination factor, enrichment factor, geoaccumulation index, and risk assessment index revealed that Cd reached high contamination and very high eco-risk, Pb had medium contamination but low eco-risk, Zn showed low contamination and low eco-risk, and Cu was not contaminated in the soils. The data indicated that Cd was the priority to concern in the soils of Hailuogou Glacier catchment. PMID:26581692

  7. Silver Nanoparticles Entering Soils via the Wastewater-Sludge-Soil Pathway Pose Low Risk to Plants but Elevated Cl Concentrations Increase Ag Bioavailability.

    PubMed

    Wang, Peng; Menzies, Neal W; Dennis, Paul G; Guo, Jianhua; Forstner, Christian; Sekine, Ryo; Lombi, Enzo; Kappen, Peter; Bertsch, Paul M; Kopittke, Peter M

    2016-08-01

    The widespread use of silver nanoparticles (Ag-NPs) results in their movement into wastewater treatment facilities and subsequently to agricultural soils via application of contaminated sludge. On-route, the chemical properties of Ag may change, and further alterations are possible upon entry to soil. In the present study, we examined the long-term stability and (bio)availability of Ag along the "wastewater-sludge-soil" pathway. Synchrotron-based X-ray absorption spectroscopy (XAS) revealed that ca. 99% of Ag added to the sludge reactors as either Ag-NPs or AgNO3 was retained in sludge, with ≥79% of this being transformed to Ag2S, with the majority (≥87%) remaining in this form even after introduction to soils at various pH values and Cl concentrations for up to 400 days. Diffusive gradients in thin films (DGT), chemical extraction, and plant uptake experiments indicated that the potential (bio)availability of Ag in soil was low but increased markedly in soils with elevated Cl, likely due to the formation of soluble AgClx complexes in the soil solution. Although high Cl concentrations increased the bioavailability of Ag markedly, plant growth was not reduced in any treatment. Our results indicate that Ag-NPs entering soils through the wastewater-sludge-soil pathway pose low risk to plants due to their conversion to Ag2S in the wastewater treatment process, although bioavailability may increase in saline soils or when irrigated with high-Cl water. PMID:27380126

  8. Health risk assessment of urban population exposure to contaminants in the soils of the Southern Kuzbass

    NASA Astrophysics Data System (ADS)

    Osipova, N. A.; Tarasova, N. P.; Osipov, K. Yu.; Maximova, D. I.

    2015-11-01

    This study concerns the human health risk due to exposure of Co, Cu, As, Mn contained in soils of the Southern Kuzbass, where the coal industry is developed. Soil samples of 200 were taken in Mezhdurechensk - city with intensive coal mining and processing industries. The content of heavy metals in samples were determined using the electron spectroscopy. Several samples were also investigated by methods of the instrumental neutron activation analysis (INAA) and the inductively coupled plasma mass spectrometry (ICP-MS). With regard to the effects of heavy metals on the adult population health the total Hazard Index (HI) for ingestion and inhalation routes was 0.87×10-1 and 7.8×10-1 respectively. According to the contribution of Co, Cu, As, Mn to the total HI the elements form the decreasing series Mn (0,42-0,50)> Co (0.18-0.20)> Cu (0,13-0,19 )> As (0,05-0,09). These chemical elements are present in the organic and inorganic forms in coals and coal wastes. Ranking the city territory has shown that administrative districts have different HI values (8.4 10-1 - 8.8 10-1). When analyzing the human health risks of coal mining and coal-processing enterprises the impact of heavy metals as components of coals and combustion products should be taken into account.

  9. TPH-contaminated Mexican refinery soil: health risk assessment and the first year of changes.

    PubMed

    Iturbe, Rosario; Flores, Rosa M; Flores, Carlos R; Torres, Luis G

    2004-02-01

    The soil of a coastal Mexican refinery is quite contaminated, especially by hydrocarbons, with detected concentrations up to 130000 mg kg(-1) as TPHs (total petroleum hydrocarbons). The main sources of contamination are pipelines, valves, and old storage tanks, besides the land disposal of untreated hydrocarbon sediments derived from the cleaning of storage tanks. A health risk assessment (HRA) was carried out in order to measure the risk hazard indexes and clean-up standards for the refinery soil. HRA suggested the following actions to be taken: benzene concentrations must be reduced in eight of the 16 studied refinery zones to 0.0074-0.0078 mg kg(-1). Also, vanadium concentration must be reduced in two zones up to a concentration of 100 mg kg(-1). In only one of all of the studied zones, benzo(a)pyrene concentration must be reduced to 0.1 mg kg(-1). After 1 yr, TPHs showed a diminution of about 52%. Even though TPHs concentrations were variable, during 1999 the average concentrations were as much as 15.5 times the goal concentration. For year 2000, TPHs concentrations were only 7.4-fold the proposed value. For the 1999-2000 period, PAHs (polycyclic aromatic hydrocarbons) concentrations decreased by 82%. Some PAHs with 2, 3, 4, and 5 aromatic rings were removed up to 100% values. PMID:14969447

  10. Health Risk Assessment of Heavy Metals in Soils from Witwatersrand Gold Mining Basin, South Africa

    PubMed Central

    Kamunda, Caspah; Mathuthu, Manny; Madhuku, Morgan

    2016-01-01

    The study evaluates the health risk caused by heavy metals to the inhabitants of a gold mining area. In this study, 56 soil samples from five mine tailings and 17 from two mine villages were collected and analyzed for Asernic (As), Lead (Pb), Mercury (Hg), Cadmium (Cd), Chromium (Cr), Cobalt (Co), Nickel (Ni), Copper (Cu) and Zinc (Zn) using ICP-MS. Measured concentrations of these heavy metals were then used to calculate the health risk for adults and children. Their concentrations were such that Cr > Ni > As > Zn > Cu > Co > Pb > Hg > Cd, with As, Cr and Ni higher than permissible levels. For the adult population, the Hazard Index value for all pathways was found to be 2.13, making non-carcinogenic effects significant to the adult population. For children, the Hazard Index value was 43.80, a value >>1, which poses serious non-carcinogenic effect to children living in the gold mining area. The carcinogenic risk was found to be 1.7 × 10−4 implying that 1 person in every 5882 adults may be affected. In addition, for children, in every 2725 individuals, 1 child may be affected (3.67 × 10−4). These carcinogenic risk values were both higher than acceptable values. PMID:27376316

  11. Health Risk Assessment of Heavy Metals in Soils from Witwatersrand Gold Mining Basin, South Africa.

    PubMed

    Kamunda, Caspah; Mathuthu, Manny; Madhuku, Morgan

    2016-01-01

    The study evaluates the health risk caused by heavy metals to the inhabitants of a gold mining area. In this study, 56 soil samples from five mine tailings and 17 from two mine villages were collected and analyzed for Asernic (As), Lead (Pb), Mercury (Hg), Cadmium (Cd), Chromium (Cr), Cobalt (Co), Nickel (Ni), Copper (Cu) and Zinc (Zn) using ICP-MS. Measured concentrations of these heavy metals were then used to calculate the health risk for adults and children. Their concentrations were such that Cr > Ni > As > Zn > Cu > Co > Pb > Hg > Cd, with As, Cr and Ni higher than permissible levels. For the adult population, the Hazard Index value for all pathways was found to be 2.13, making non-carcinogenic effects significant to the adult population. For children, the Hazard Index value was 43.80, a value >1, which poses serious non-carcinogenic effect to children living in the gold mining area. The carcinogenic risk was found to be 1.7 × 10(-4) implying that 1 person in every 5882 adults may be affected. In addition, for children, in every 2725 individuals, 1 child may be affected (3.67 × 10(-4)). These carcinogenic risk values were both higher than acceptable values. PMID:27376316

  12. Geochemical fractions and risk assessment of trace elements in soils around Jiaojia gold mine in Shandong Province, China.

    PubMed

    Cao, Feifei; Kong, Linghao; Yang, Liyuan; Zhang, Wei

    2015-09-01

    Soils located adjacent to the Jiaojia gold mine were sampled and analyzed to determine the degree of which they were contaminated by trace elements (Hg, As, Cd, Pb, Cu, and Zn) in Shandong Province, China. All 18 samples exhibited mean Hg, As, Cd, and Pb concentrations in excess of local background values, while the mean concentrations of Cu and Zn were below the background values. In addition, the concentrations of trace elements in gold smelter (GS) soils were higher than in the gold mine (GM) soils. The result from a modified Tessier sequential extraction procedure was that with the exception of Cu in soils near the smelter, the trace elements were predominantly associated with the residual fraction. After residual fraction, most Hg was mainly humic acid and strong organic fraction, while most As was the humic acid. Cd was associated with the water soluble, ion exchange, and carbonate fractions compared with the other trace elements. Furthermore, Cu, Pb, and Zn were more concentrated in the humic acid and Fe/Mn oxide fraction. The fractions of trace elements were affected by soil pH and Ec (Electrical conductivity). The humic acid fraction of Hg as well as the ion exchange fraction of Cd and Zn displayed negative correlations with soil pH. The strong organic fraction of Hg, the Fe/Mn oxide fraction of Cd, and the carbonate fraction of Zn were positively related to the soil Ec. The strong organic fraction and ion exchange fraction of Zn were negatively related to soil Ec. However, the ion exchange and carbonate fractions of As showed significant positive correlations with soil pH. A calculated individual availability factor (A f (i) ) is used; the values of each trace element in the soils are in the following order: Cu > Cd > Pb > Zn > As > Hg. When combined with a risk assessment code, data suggest that Hg, As, Pb, and Zn levels showed low risk for the environment, whereas Cd levels in soils adjacent to the GM and Cu levels in soils adjacent to the GS showed

  13. Case studies of geophysical imaging for road foundation design on soft soils and embankment risk assessment

    NASA Astrophysics Data System (ADS)

    Whiteley, Robert J.; Kelly, Richard B.; Stewart, Simon B.

    2015-12-01

    Population growth along the coast of eastern Australia has increased demand for new and upgraded transport infrastructure within intervening coastal floodplains and steeper hinterland areas. This has created additional challenges for road foundation design. The floodplain areas in this region are underlain by considerable thicknesses of recently deposited alluvial and clayey marine sediments. If characterisation of these deposits is inadequate they can increase road construction costs and affect long-term road stability and serviceability. Case studies from a major coastal highway upgrade demonstrate how combining surface wave seismic and electrical geophysical imaging with conventional geotechnical testing enhances characterisation of these very soft and soft soils. The geophysical results also provide initial foundation design parameters such as void ratio and pre-consolidation pressure. A further significant risk issue for roads is potential embankment instability. This can occur during new road construction or when upgrades of existing embankments are required. Assessing the causes of instability of existing steeper embankments with drilling and probing is often difficult and costly due to access and safety problems. In these situations combinations of electrical, ground penetrating radar and P-wave seismic imaging technologies can rapidly provide information on the likely conditions below both the roadway and embankment. Case studies show the application of these technologies on two unstable road embankments. It is concluded that the application of both geophysical imaging and geotechnical testing is a cost-effective enhancement for site characterisation of soft soils and for risk assessment of potentially unstable embankments. This approach overcomes many of the current limitations of conventional methods of site investigation that provide point location data only. The incorporation of geophysics into a well crafted site investigation allows concentration on

  14. [Transportation and risk assessment of heavy metal pollution in water-soil from the Riparian Zone of Daye Lake, China].

    PubMed

    Zhang, Jia-quan; Li, Xiu; Zhang, Quan-fa; Li, Qiong; Xiao, Wen-sheng; Wang, Yong-kui; Zhang, Jian-chun; Gai, Xi-guang

    2015-01-01

    Each 20 water samples and soil samples (0-10 cm, 10-20 cm) were collected from the riparian zone of Daye Lake in dry season during March 2013. Heavy metals (Cu, Ph, Cd, Zn) have been detected by flame atomic absorption spectrometric (FAAS). The results showed that the average concentrations of Cu, Pb, Cd, Zn in the water were 7.14, 25.94, 15.72 and 37.58 microg x L(-1), respectively. The concentration of Cu was higher than the five degree of the surface water environment quality standard. The average concentrations of Cu, Pb, Cd, Zn in soil(0-10 cm) were 108.38, 53.92, 3.55, 139.26 mg x kg(-1) in soil (10-20 cm) were 93.00, 51.72, 2.08, 171.00 mg x kg(-1), respectively. The Cd concentrations were higher than the three grade value of the national soil environment quality standard. The transportation of Pb from soil to water was relatively stable, and Zn was greatly influenced by soil property and the surrounding environment from soil to water. The transformation of heavy metal in west riparian zone was higher than that of east riparian zone. The potential environmental risk was relatively high. Cu, Pb, Cd, Zn were dominated by residue fraction of the modified BCR sequential extraction method. The overall migration order of heavy metal element was: Pb > Cu > Cd > Zn. There were stronger transformation and higher environmental pollution risk of Cu, Pb. The index of assessment and potential ecological risk coefficient indicated that heavy metal pollution in soil (0-10 cm) was higher than the soil (10-20 cm), Cd was particularly serious. PMID:25898664

  15. Heavy metal pollution and ecological risk assessment of the paddy soils near a zinc-lead mining area in Hunan.

    PubMed

    Lu, Sijin; Wang, Yeyao; Teng, Yanguo; Yu, Xuan

    2015-10-01

    Soil pollution by Cd, Hg, As, Pb, Cr, Cu, and Zn was characterized in the area of the mining and smelting of metal ores at Guiyang, northeast of Hunan Province. A total of 150 topsoil (0-20 cm) samples were collected in May 2012 with a nominal density of one sample per 4 km(2). High concentrations of heavy metals especially, Cd, Zn, and Pb were found in many of the samples taken from surrounding paddy soil, indicating a certain extent of spreading of heavy metal pollution. Sequential extraction technique and risk assessment code (RAC) were used to study the mobility of chemical forms of heavy metals in the soils and their ecological risk. The results reveal that Cd represents a high ecological risk due to its highest percentage of the exchangeable and carbonate fractions. The metals of Zn and Cu pose a medium risk, and the rest of the metals represent a low environmental risk. The range of the potential ecological risk of soil calculated by risk index (RI) was 123.5~2791.2 and revealed a considerable-high ecological risk in study area especially in the neighboring and surrounding the mining activities area. Additionally, cluster analyses suggested that metals such as Pb, As, Hg, Zn, and Cd could be from the same sources probably related to the acidic drainage and wind transport of dust. Cluster analysis also clearly distinguishes the samples with similar characteristics according to their spatial distribution. The results could be used during the ecological risk screening stage, in conjunction with total concentrations and metal fractionation values to better estimate ecological risk. PMID:26373302

  16. Environmental impacts on soil and groundwater at airports: origin, contaminants of concern and environmental risks.

    PubMed

    Nunes, L M; Zhu, Y-G; Stigter, T Y; Monteiro, J P; Teixeira, M R

    2011-11-01

    Environmental impacts of airports are similar to those of many industries, though their operations expand over a very large area. Most international impact assessment studies and environmental management programmes have been giving less focus on the impacts to soil and groundwater than desirable. This may be the result of the large attention given to air and noise pollution, relegating other environmental descriptors to a second role, even when the first are comparatively less relevant. One reason that contributes to such "biased" evaluation is the lack of systematic information about impacts to soil and groundwater from airport activities, something the present study intends to help correct. Results presented here include the review of over seven hundred documents and online databases, with the objective of obtaining the following information to support environmental studies: (i) which operations are responsible for chemical releases?; (ii) where are these releases located?; (iii) which contaminants of concern are released?; (iv) what are the associated environmental risks? Results showed that the main impacts occur as a result of fuel storage, stormwater runoff and drainage systems, fuel hydrant systems, fuel transport and refuelling, atmospheric deposition, rescue and fire fighting training areas, winter operations, electrical substations, storage of chemical products by airport owners or tenants, and maintenance of green areas. A new method for ranking environmental risks of organic substances, based on chemical properties, is proposed and applied. Results show that the contaminants with the highest risks are the perfluorochemicals, benzene, trichloroethylene and CCl(4). The obtained information provides a basis for establishing the planning and checking phases of environmental management systems, and may also help in the best design of pollution prevention measures in order to avoid or reduce significant environmental impacts from airports. PMID:22002748

  17. Assessment of bioaccessibility and exposure risk of arsenic and lead in urban soils of Guangzhou City, China.

    PubMed

    Lu, Ying; Yin, Wei; Huang, Longbin; Zhang, Ganlin; Zhao, Yuguo

    2011-04-01

    Soil ingestion is an important human exposure pathway of heavy metals in urban environments with heavy metal contaminated soils. This study aims to assess potential health risks of heavy metals in soils sampled from an urban environment where high frequency of human exposure may be present. A bioaccessibility test is used, which is an in vitro gastrointestinal (IVG) test of soluble metals under simulated physiological conditions of the human digestion system. Soil samples for assessing the oral bioaccessibility of arsenic (As) and lead (Pb) were collected from a diverse range of different land uses, including urban parks, roadsides, industrial sites and residential areas in Guangzhou City, China. The soil samples contained a wide range of total As (10.2 to 61.0 mg kg(-1)) and Pb (38.4 to 348 mg kg(-1)) concentrations. The bioaccessibility of As and Pb in the soil samples were 11.3 and 39.1% in the stomach phase, and 1.9 and 6.9% in the intestinal phase, respectively. The As and Pb bioaccessibility in the small intestinal phase was significantly lower than those in the gastric phase. Arsenic bioaccessibility was closely influenced by soil pH and organic matter content (r (2) = 0.451, p < 0.01) in the stomach phase, and by organic matter, silt and total As contents (r (2) = 0.604, p < 0.001) in the intestinal phase. The general risk of As and Pb intake for children from incidental ingestion of soils is low, compared to their maximum doses, without causing negative human health effects. The exposure risk of Pb in the soils ranked in the order of: industrial area/urban parks > residential area/road side. Although the risk of heavy metal exposure from direct ingestion of urban soils is relatively low, the risk of inhalation of fine soil particulates in the air remains to be evaluated. PMID:20524051

  18. Mapping the spatial patterns of field traffic and traffic intensity to predict soil compaction risks at the field scale

    NASA Astrophysics Data System (ADS)

    Duttmann, Rainer; Kuhwald, Michael; Nolde, Michael

    2015-04-01

    Soil compaction is one of the main threats to cropland soils in present days. In contrast to easily visible phenomena of soil degradation, soil compaction, however, is obscured by other signals such as reduced crop yield, delayed crop growth, and the ponding of water, which makes it difficult to recognize and locate areas impacted by soil compaction directly. Although it is known that trafficking intensity is a key factor for soil compaction, until today only modest work has been concerned with the mapping of the spatially distributed patterns of field traffic and with the visual representation of the loads and pressures applied by farm traffic within single fields. A promising method for for spatial detection and mapping of soil compaction risks of individual fields is to process dGPS data, collected from vehicle-mounted GPS receivers and to compare the soil stress induced by farm machinery to the load bearing capacity derived from given soil map data. The application of position-based machinery data enables the mapping of vehicle movements over time as well as the assessment of trafficking intensity. It also facilitates the calculation of the trafficked area and the modeling of the loads and pressures applied to soil by individual vehicles. This paper focuses on the modeling and mapping of the spatial patterns of traffic intensity in silage maize fields during harvest, considering the spatio-temporal changes in wheel load and ground contact pressure along the loading sections. In addition to scenarios calculated for varying mechanical soil strengths, an example for visualizing the three-dimensional stress propagation inside the soil will be given, using the Visualization Toolkit (VTK) to construct 2D or 3D maps supporting to decision making due to sustainable field traffic management.

  19. Human health risk assessment of heavy metals in soil-vegetable system: a multi-medium analysis.

    PubMed

    Liu, Xingmei; Song, Qiujin; Tang, Yu; Li, Wanlu; Xu, Jianming; Wu, Jianjun; Wang, Fan; Brookes, Philip Charles

    2013-10-01

    Vegetable fields near villages in China are suffering increasing heavy metal damages from various pollution sources including agriculture, traffic, mining and Chinese typical local private family-sized industry. 268 vegetable samples which included rape, celery, cabbages, carrots, asparagus lettuces, cowpeas, tomatoes and cayenne pepper and their corresponding soils in three economically developed areas of Zhejiang Province, China were collected, and the concentrations of five heavy metals (Pb, Cd, Cr, Hg and As) in all the samples were determined. The health risk assessment methods developed by the United States Environmental Protection Agency (US EPA) were employed to explore the potential health hazards of heavy metals in soils growing vegetables. Results showed that heavy metal contaminations in investigated vegetables and corresponding soils were significant. Pollution levels varied with metals and vegetable types. The highest mean soil concentrations of heavy metals were 70.36 mg kg(-1) Pb, 47.49 mg kg(-1) Cr, 13.51 mg kg(-1) As, 0.73 mg kg(-1) for Cd and 0.67 mg kg(-1) Hg, respectively, while the metal concentrations in vegetables and corresponding soils were poorly correlated. The health risk assessment results indicated that diet dominated the exposure pathways, so heavy metals in soil samples might cause potential harm through food-chain transfer. The total non-cancer and cancer risk results indicated that the investigated arable fields near industrial and waste mining sites were unsuitable for growing leaf and root vegetables in view of the risk of elevated intakes of heavy metals adversely affecting food safety for local residents. Chromium and Pb were the primary heavy metals posing non-cancer risks while Cd caused the greatest cancer risk. It was concluded that more effective controls should be focused on Cd and Cr to reduce pollution in this study area. PMID:23831799

  20. Autoclave treatment of pig manure does not reduce the risk of transmission and transfer of tetracycline resistance genes in soil: successive determinations with soil column experiments.

    PubMed

    Kang, Yijun; Gu, Xian; Hao, Yangyang; Hu, Jian

    2016-03-01

    The increasing use of antibiotics, especially tetracycline, in livestock feed adversely affects animal health and ecological integrity. Therefore, approaches to decrease this risk are urgently needed. High temperatures facilitate antibiotic degradation; whether this reduces transmission risk and transfer of tetracycline-resistant bacteria (TRBs) and tetracycline resistance genes (TRGs) in soil remains unknown. Successive experiments with soil columns evaluated the effects of autoclaving pig manure (APM) on soil TRB populations and TRGs over time at different soil depths. The data showed sharp increases in TRB populations and TRGs in each subsoil layer of PM (non-APM) and APM treatments within 30 days, indicating that TRBs and TRGs transferred rapidly. The level of TRBs in the upper soil layers was approximately 15-fold higher than in subsoils. TRBs were not dependent on PM and APM levels, especially in the late phase. Nevertheless, higher levels of APM led to rapid expansion of TRBs as compared to PM. Moreover, temporal changes in TRB frequencies in total culturable bacteria (TCBs) were similar to TRBs, indicating that the impact of PM or APM on TRBs was more obvious than for TCBs. TRBs were hypothesized to depend on the numbers of TRGs and indigenous recipient bacteria. In the plough layer, five TRGs (tetB, tetG, tetM, tetW, and tetB/P) existed in each treatment within 150 days. Selective pressure of TC may not be a necessary condition for the transfer and persistence of TRGs in soil. High temperatures might reduce TRBs in PM, which had minimal impact on the transmission and transfer of TRGs in soil. Identifying alternatives to decrease TRG transmission remains a major challenge. PMID:26517996

  1. Risk potentials for humans of original and remediated PAH-contaminated soils: application of biomarkers of effect.

    PubMed

    Roos, Peter H; Tschirbs, Sebastian; Pfeifer, Frank; Welge, Peter; Hack, Alfons; Wilhelm, Michael; Bolt, Hermann M

    2004-12-15

    Contaminated soils represent a potential health risk for the human population. Risk assessment for humans requires specific methods, which must reflect the peculiarities of human behaviour, physiology and biochemistry with respect to contaminant uptake and processing. Biomarkers of effect or exposure have become an appropriate tool. Organic pollutants influence the expression profile of cytochromes P450 (CYP), and CYP1A1 has been shown to be a suitable biomarker for polycyclic aromatic hydrocarbons (PAH). The latter are widely distributed in soils and constitute an important soil contamination. Upon intake of PAH-contaminated soils, CYP1A1 is induced in various organs of rats and minipigs. Increased CYP1A1-levels in lung, kidney and spleen, after oral soil intake, indicate that contaminants escape the primary duodenal and hepatic metabolism and reach further organs. Dose-response relationships reveal that induction effects are to be expected in children based on known exposure conditions. Generally, CYP1A1-induction does not correlate with results of toxicity tests with lower organisms, performed with the same soils. The organic carbon content is largely responsible for this discrepancy. It severely affects the toxicity of soil bound PAH for microorganisms, but obviously affects the mobilization efficiency for PAH in the gastro-intestinal tract of mammals to a minor extent. Soil remediation by different methods may result in a significant reduction of the PAH content and of toxicity. Ingestion of remediated soils by rats shows, however, that the induction potential for CYP1A1 is only slightly decreased after remediation. This means that the major inducing components resist biological remediation or soil washing and remain in the soil. Because data obtained with experimental animals form the guiding principle for in vitro tests to be developed, the suitability of the animal model used for extrapolations to humans has to be proven. Upon soil ingestion, minipigs show

  2. Risk of soil-transmitted helminth infections on agritourism farms in central and eastern Poland.

    PubMed

    Gawor, Jakub; Borecka, Anna

    2015-12-01

    Agritourism provides ecological tourist services for urban dwellers in rural areas. Agritourism farms offer space and attractive scenery for people seeking to rest in quiet place and wanting healthy, outdoor recreational activities. The high epidemiological standard of agritourism farms is beneficial for the health of the farm owners and the guests. Upgraded level of the farm sanitation, also from parasitological point of view is of great importance, especially that among agritourism farms guests predominate families with small children. A field survey was carried out in 57 farms in central-eastern Poland to evaluate the environmental risk factors for geohelminth infections on agritourism farms offering tourist services for urban dwellers. Samples of soil were collected from 76 sites, i.e. yards surrounding houses, vegetable, fruit and flower gardens, playgrounds and sandpits. In addition, samples were taken from 27 public places of recreation (playgrounds at forest clearing) visited by agritourism farm guests. During visits the farms were inspected and the owners were questioned about their awareness of the threat of parasitic infections. Soil contamination with geohelminth eggs was found in 4 examined farms (7.0%), in one locality on each farm. The eggs of Toxocara spp. and Ascaris spp. were detected in single samples from 3 backyards (6.4%) and one sandpit (10.0%). In the soil samples from places of recreation outside the farms eggs of human or animal helminths were not identified. The results of this study showed that the risk of helminth infections on agritourism farms is low, since geohelminth eggs (1-3 per sample) were detected only in four samples (0.5%) among 760 collected from farms households. The farm owners must be aware of the importance of preventive measures to eliminate the environmental contamination with eggs of zoonotic soiltransmitted helminths. Special attention should be paid to the risk of intestinal parasites of cats of semi domestic

  3. Accumulation of Heavy Metals in Vegetable Species Planted in Contaminated Soils and the Health Risk Assessment

    PubMed Central

    Zhou, Hang; Yang, Wen-Tao; Zhou, Xin; Liu, Li; Gu, Jiao-Feng; Wang, Wen-Lei; Zou, Jia-Ling; Tian, Tao; Peng, Pei-Qin; Liao, Bo-Han

    2016-01-01

    The objectives of the present study were to investigate heavy metal accumulation in 22 vegetable species and to assess the human health risks of vegetable consumption. Six vegetable types were cultivated on farmland contaminated with heavy metals (Pb, Cd, Cu, Zn, and As). The target hazard quotient (THQ) method was used to assess the human health risks posed by heavy metals through vegetable consumption. Clear differences were found in the concentrations of heavy metals in edible parts of the different vegetables. The concentrations of heavy metals decreased in the sequence as leafy vegetables > stalk vegetables/root vegetables/solanaceous vegetables > legume vegetables/melon vegetables. The ability of leafy vegetables to uptake and accumulate heavy metals was the highest, and that of melon vegetables was the lowest. This indicated that the low accumulators (melon vegetables) were suitable for being planted on contaminated soil, while the high accumulators (leafy vegetables) were unsuitable. In Shizhuyuan area, China, the total THQ values of adults and children through consumption of vegetables were 4.12 and 5.41, respectively, suggesting that the residents may be facing health risks due to vegetable consumption, and that children were vulnerable to the adverse effects of heavy metal ingestion. PMID:26959043

  4. Development of risk-based cleanup levels for petroleum-related contaminants in soil and groundwater

    SciTech Connect

    Lau, V.; Hoffman-Kiefer, A.

    1995-12-31

    The US Environmental Protection Agency`s (EPA) Office of Underground Storage Tanks (USTs) have provided final guidance for cleanup of USTs based on individual state-approved programs. This allows cleanup levels to fluctuate by several orders of magnitude from state to state depending on the local soil, climate, geology, and demographics of the region. A recent study conducted by the Lawrence Livermore National Laboratory in California indicates that releases of petroleum-related contaminants from leaking USTs rarely pose an actual human health concern. The study recommends that ASTM`s Risk-Based Corrective Actions (RBCA) framework be applied on UST contaminated sites to provide a systematic, consistent approach that can be adopted on a state level, but permits local implementation. The authors have adopted the RBCA approach to estimate cleanup levels for key petroleum-related constituents including total petroleum hydrocarbon (TPH); benzene, toluene, ethylbenzene, and total xylene (BTEX); and polycyclic aromatic hydrocarbons (PAHs). A tiered 2 analysis using Jury et al`s Behavior Assessment Model (BAM) was used to provide an upper bound risk-based cleanup levels for these compounds based on a sophisticated mass-balance equations. It is their contention that risk-based cleanup levels are significantly higher than guidance levels previously approved by state agencies.

  5. Patterns and Risk Factors of Soil-Transmitted Helminthiasis among Orang Asli Subgroups in Peninsular Malaysia

    PubMed Central

    Ngui, Romano; Aziz, Shafie; Chua, Kek Heng; Aidil, Roslan Muhammad; Lee, Soo Ching; Tan, Tiong Kai; Sani, Mistam Mohd; Arine, Ahmad Fadzlun; Rohela, Mahmud; Lim, Yvonne A. L.

    2015-01-01

    A cross-sectional study was conducted to provide comprehensive data on the patterns and associated risk factors of soil-transmitted helminth (STH) infections among five Orang Asli subgroups in Peninsular Malaysia. The overall prevalence of STH infections was 59.9% (95% confidence interval [CI] = 56.1–63.7%). Trichuris trichiura (54.3%; 95% CI = 50.4–58.2%) was the predominant species followed by Ascaris lumbricoides (26.7%; 95% CI = 23.3–30.1%) and hookworm (9.1%; 95% CI = 6.9–11.3%). This study showed diversity for STH infections by subgroup with poverty and personal sanitary behavior as important risk factors for infection. Risk profile analyses indicating that Orang Kuala subgroup who has a generally well-developed infrastructure and better quality of life had a low rate of infection. There is a need for poverty reduction and promotion of deworming programs along with mass scale campaigns to create awareness about health and hygiene to reduce STH infections. PMID:26055746

  6. Patterns and Risk Factors of Soil-Transmitted Helminthiasis Among Orang Asli Subgroups in Peninsular Malaysia.

    PubMed

    Ngui, Romano; Aziz, Shafie; Chua, Kek Heng; Aidil, Roslan Muhammad; Lee, Soo Ching; Tan, Tiong Kai; Sani, Mistam Mohd; Arine, Ahmad Fadzlun; Rohela, Mahmud; Lim, Yvonne A L

    2015-08-01

    A cross-sectional study was conducted to provide comprehensive data on the patterns and associated risk factors of soil-transmitted helminth (STH) infections among five Orang Asli subgroups in Peninsular Malaysia. The overall prevalence of STH infections was 59.9% (95% confidence interval [CI] = 56.1-63.7%). Trichuris trichiura (54.3%; 95% CI = 50.4-58.2%) was the predominant species followed by Ascaris lumbricoides (26.7%; 95% CI = 23.3-30.1%) and hookworm (9.1%; 95% CI = 6.9-11.3%). This study showed diversity for STH infections by subgroup with poverty and personal sanitary behavior as important risk factors for infection. Risk profile analyses indicating that Orang Kuala subgroup who has a generally well-developed infrastructure and better quality of life had a low rate of infection. There is a need for poverty reduction and promotion of deworming programs along with mass scale campaigns to create awareness about health and hygiene to reduce STH infections. PMID:26055746

  7. Geostatistical modeling of the spatial variability and risk areas of southern root-knot nematodes in relation to soil properties

    PubMed Central

    Ortiz, B.V.; Perry, C.; Goovaerts, P.; Vellidis, G.; Sullivan, D.

    2010-01-01

    Identifying the spatial variability and risk areas for southern root-knot nematode [Meloidogyne incognita (Kofoid & White) Chitwood] (RKN) is key for site-specific management (SSM) of cotton (Gossypium hirsutum L.) fields. The objectives of this study were to: (i) determine the soil properties that influence RKN occurrence at different scales; and (ii) delineate risk areas of RKN by indicator kriging. The study site was a cotton field located in the southeastern coastal plain region of the USA. Nested semivariograms indicated that RKN samples, collected from a 50×50 m grid, exhibited a local and regional scale of variation describing small and large clusters of RKN population density. Factorial kriging decomposed RKN and soil properties variability into different spatial components. Scale dependent correlations between RKN data showed that the areas with high RKN population remained stable though the growing season. RKN data were strongly correlated with slope (SL) at local scale and with apparent soil electrical conductivity deep (ECa-d) at both local and regional scales, which illustrate the potential of these soil physical properties as surrogate data for RKN population. The correlation between RKN data and soil chemical properties was soil texture mediated. Indicator kriging (IK) maps developed using either RKN, the relation between RKN and soil electrical conductivity or a combination of both, depicted the probability for RKN population to exceed the threshold of 100 second stage juveniles/100 cm3 of soil. Incorporating ECa-d as soft data improved predictions favoring the reduction of the number of RKN observations required to map areas at risk for high RKN population. PMID:20717481

  8. Geostatistical modeling of the spatial variability and risk areas of southern root-knot nematodes in relation to soil properties.

    PubMed

    Ortiz, B V; Perry, C; Goovaerts, P; Vellidis, G; Sullivan, D

    2010-05-01

    Identifying the spatial variability and risk areas for southern root-knot nematode [Meloidogyne incognita (Kofoid & White) Chitwood] (RKN) is key for site-specific management (SSM) of cotton (Gossypium hirsutum L.) fields. The objectives of this study were to: (i) determine the soil properties that influence RKN occurrence at different scales; and (ii) delineate risk areas of RKN by indicator kriging. The study site was a cotton field located in the southeastern coastal plain region of the USA. Nested semivariograms indicated that RKN samples, collected from a 50×50 m grid, exhibited a local and regional scale of variation describing small and large clusters of RKN population density. Factorial kriging decomposed RKN and soil properties variability into different spatial components. Scale dependent correlations between RKN data showed that the areas with high RKN population remained stable though the growing season. RKN data were strongly correlated with slope (SL) at local scale and with apparent soil electrical conductivity deep (EC(a-d)) at both local and regional scales, which illustrate the potential of these soil physical properties as surrogate data for RKN population. The correlation between RKN data and soil chemical properties was soil texture mediated. Indicator kriging (IK) maps developed using either RKN, the relation between RKN and soil electrical conductivity or a combination of both, depicted the probability for RKN population to exceed the threshold of 100 second stage juveniles/100 cm(3) of soil. Incorporating EC(a-d) as soft data improved predictions favoring the reduction of the number of RKN observations required to map areas at risk for high RKN population. PMID:20717481

  9. Occurrence and risk assessment of polycyclic aromatic hydrocarbons in soil from the Tiefa coal mine district, Liaoning, China.

    PubMed

    Liu, Jingjing; Liu, Guijian; Zhang, Jiamei; Yin, Hao; Wang, Ruwei

    2012-10-26

    In order to evaluate soil-associated polycyclic aromatic hydrocarbons (PAHs) pollution from coal mine activities in Tiefa coal mine, Northeast China, 16 PAHs identified as priority pollutants by US Environmental Pollution Agency were determined in mining zone soil (MZS), agricultural soil (AS), local lake bank soil (LBS), a vertical soil profile and three coal gangue samples. The total concentration of 16 PAHs (defined as Σ(16)PAH, dry weight) in surface soil ranged from 5.1 to 5642.3 ng g(-1), with an arithmetic mean of 1118.3 ng g(-1). Σ(16)PAH values at the sites from MZS are significantly higher than those found in AS and LBS. The vertical distribution of PAHs indicated that these compounds can penetrate the deeper layers of the soil, especially the low-rings compounds. A complex of petrogenic origin and pyrolytic sources was found within the study area, as suggested by the isomeric ratios of PAHs. According to principal component analysis (PCA), four factors were identified in the source contribution, including coal combustion, unburned coal particulates, coal gangue and vehicular emissions. The degree of contamination and the PAH toxicity assessment suggested that the soils of the study area have been seriously polluted and pose a high potential health risk. PMID:22914869

  10. Environmental risk of heavy metal pollution and contamination sources using multivariate analysis in the soils of Varanasi environs, India.

    PubMed

    Singh, Shubhra; Raju, N Janardhana; Nazneen, Sadaf

    2015-06-01

    This study assessed soil pollution in the Varanasi environs of Uttar Pradesh in India. Assessing the concentration of potentially harmful heavy metals in the soils is imperative in order to evaluate the potential risks to human. To identify the concentration and sources of heavy metals and assess the soil environmental quality, 23 samples were collected from different locations covering dumping, road and agricultural area. The average concentrations of the heavy metals were all below the permissible limits according to soil quality guidelines except Cu (copper) and Pb (lead) in dumping and road soils. Soil heavy metal contamination was assessed on the basis of geoaccumulation index (Igeo), pollution index (PI) and integrated pollution index (IPI). The IPI of the metals ranged from 0.59 to 9.94, with the highest IPI observed in the dumping and road soils. A very significant correlation was found between Pb and Cu. The result of principal component analysis suggested that PC1 was mainly affected by the use of agrochemicals, PC2 was affected by vehicular emission and PC3 was affected by dumping waste. Meanwhile, PC4 was mainly controlled by parent material along with anthropogenic activities. Appropriate measures should be taken to minimize the heavy metal levels in soils and thus protect human health. PMID:25963764