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Last update: November 12, 2013.
1

Microbial Degradation of Pesticides.  

National Technical Information Service (NTIS)

Microbial degradation of various organochlorine, organophosphorus and carbamate pesticides by aquatic and soil microorganisms was studied. Bacteria, fungi, and an alga (Cylindrospermum sp.) metabolized DDT to water-soluble products. DDT, DDA, and 2-chloro...

M. Alexander

1977-01-01

2

PESTICIDAL ACTIVITY OF GLUCOSINOLATES AND THEIR DEGRADATION PRODUCTS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Glucosinolates are a class of water soluble organic anions whose degradation products are produced when plant cells are ruptured and the glucosinolates present in vacuoles are enzymatically hydrolyzed by myrosinase (ß-thioglucosidase glucohydrolase) to principally form substituted isothiocyanates, n...

3

Thermal Degradation Characteristics of Environmentally Sensitive Pesticide Products.  

National Technical Information Service (NTIS)

The thermal decomposition properties of the active ingredient of 16 pesticides have been theoretically examined. Experimental studies on 5 pesticide related materials were also conducted under controlled laboratory testing. Experimental studies of the hig...

D. A. Tirey B. Dellinger W. A. Rubey P. H. Taylor

1993-01-01

4

Determination of atrazine and degradation products in Luxembourgish drinking water: origin and fate of potential endocrine-disrupting pesticides  

Microsoft Academic Search

Several pesticides have been hypothesized to act as endocrine-disrupting compounds, exhibiting hormonal activity and perturbing normal physiological functions. Among these, especially s-triazine herbicides have received increased attention. Despite being banned in many countries, including the European Union, atrazine is still the world's most widely used herbicide. Despite its discontinued use, considerable concentrations of atrazine and its degradation products, mainly desethylatrazine

T. Bohn; E. Cocco; L. Gourdol; C. Guignard; L. Hoffmann

2011-01-01

5

Pesticide Degradation in Thermal Foggers.  

Technology Transfer Automated Retrieval System (TEKTRAN)

Thermal foggers are used in many parts of the world for vector control. Since thermal foggers use heat to create and help propel adulticide clouds, there is reason to examine the stability of pesticides in both diesel and water-based formulations. This study examined the degradation of 5 pesticide...

6

A study of the degradation of organophosphorus pesticides in river waters and the identification of their degradation products by chromatography coupled with mass spectrometry.  

PubMed

The degradation of selected organophosphorus pesticides (OPs), i.e., malathion and parathion, in river water, has been studied with solar simulator irradiation. The degradation of OPs and formation of degradation products were determined by chromatography coupled with mass spectrometry analysis. The effect of a photosensitizer, i.e., riboflavin, on the photolysis of OPs in a river-water environment was examined. There was no significant increase in the degradation rate in the presence of the photosensitizer. Degradation products of the OPs were identified with gas chromatography coupled with mass spectrometry (GC-MS) after derivatization by pentafluorobenzyl bromide (PFBB) and with high-performance liquid chromatography-mass spectrometry (HPLC-MS) with electrospray (ESI) or atomospheric pressure chemical ionization (APCI). Malaoxon, paraoxon, 4-nitrophenol, aminoparathion, O,O-dimethylthiophosphoric acid, and O,O-dimethyldithiophosphoric acid, have been separated and identified as the degradation products of malathion and parathion after photolysis in river water. Based on the identified transformation products, a rational degradation pathway in river water for both OPs is proposed. The identities of these products can be used to evaluate the toxic effects of the OPs and their transformation products on natural environments. PMID:18752016

Zhao, Xueheng; Hwang, Huey-Min

2008-08-28

7

Microbial degradation of the organophosphate pesticide, Ethion.  

PubMed

The organophosphate pesticide, Ethion, remains a major environmental contaminant in rural Australia and poses a significant threat to environmental and public health. The aerobic degradation of Ethion by mesophilic bacteria isolated from contaminated soils surrounding disused cattle dip sites was investigated. Two isolates, identified as Pseudomonas and Azospirillum species, were capable of biodegrading Ethion when cultivated in minimal salts medium. The abiotic hydrolytic degradation products of Ethion such as Ethion Dioxon and O,O-diethylthiosphosphate were not detected. The data suggest the rapid degradation of Ethion to support microbial growth. The results have implications for the development of a bioremediation strategy. PMID:15500978

Foster, L John R; Kwan, Bia H; Vancov, Tony

2004-11-01

8

Factors influencing degradation of pesticides in soil.  

PubMed

Degradation and sorption of six acidic pesticides (2,4-D, dicamba, fluroxypyr, fluazifop-P, metsulfuron-methyl, and flupyrsulfuron-methyl) and four basic pesticides (metribuzin, terbutryn, pirimicarb, and fenpropimorph) were determined in nine temperate soils. Results were submitted to statistical analyses against a wide range of soil and pesticide properties to (i) identify any commonalities in factors influencing rate of degradation and (ii) determine whether there was any link between sorption and degradation processes for the compounds and soils studied. There were some marked differences between the soils in their ability to degrade the different pesticides. The parameters selected to explain variations in degradation rates depended on the soil-pesticide combination. The lack of consistent behavior renders a global approach to prediction of degradation unrealistic. The soil organic carbon content generally had a positive influence on degradation. The relationship between pH and degradation rates depended on the dominant mode of degradation for each pesticide. There were positive relationships between sorption and rate of degradation for metsulfuron-methyl, pirimicarb, and all acidic pesticides considered together (all P < 0.001) and for dicamba and all bases considered together (P < 0.05). No relationship between these processes was observed for the remaining seven individual pesticides. PMID:17488087

Kah, Melanie; Beulke, Sabine; Brown, Colin D

2007-05-09

9

ORGANOPHOSPHATE PESTICIDE DEGRADATION PATHWAYS DURING DRINKING WATER TREATMENT  

EPA Science Inventory

Free chlorine has been found to react with organophosphate (OP) pesticides resulting in the more toxic oxon products. We will discuss OP pesticide degradation pathways and modeling in the presence of chlorine and chloramines, as well as present a relationship between structure a...

10

Disposal and degradation of pesticide waste.  

PubMed

Generation of pesticide waste is inevitable during every agricultural operation from storage to use and equipment cleanup. Large-scale pesticide manufacturers can afford sophisticated recovery, treatment, and cleanup techniques. Small-scale pesticide users, for example, single farms or small application businesses, struggle with both past waste problems, including contaminated soils, and disposal of unused product and equipment rinsewater. Many of these problems have arisen as a result of inability to properly handle spills during, equipment loading and rinsewater generated after application. Small-scale facilities also face continued problems of wastewater handling. Old, obsolete pesticide stocks are a vexing problem in numerous developing countries. Pesticide waste is characterized by high concentrations of a diversity of chemicals and associated adjuvants. Dissipation of chemicals at elevated concentrations is much slower than at lower concentrations, in part because of microbial toxicity and mass transfer limitations. High concentrations of pesticides may also move faster to lower soil depths, especially when pore water becomes saturated wish a compound. Thus, if pesticide waste is not properly disposed of, groundwater and surface water contamination become probable. The Waste Management Hierarchy developed as an Australian Code of Practice can serve as a guide for development of a sound waste management plan. In order of desirability, the course of actions include waste avoidance, waste reduction, waste recycling, waste treatment, and waste disposal. Proper management of pesticide stocks, including adequate storage conditions, good inventory practices, and regular turnover of products,. will contribute to waste avoidance and reduction over the long-term. Farmers can also choose to use registered materials that have the lowest recommended application rates or are applied in the least volume of water. Wastewater that is generated during equipment rinsing can be recycled by spraying it onto cropland, thus avoiding a soil contamination problem. If it is not feasible to spray out rinsates, then water treatment becomes necessary. However, for small waste generators, practical technology is still too experimental and not easily implemented on an individual farm or at a small application business. Nevertheless, research has been quite active in application of advanced oxidation processes (UV/ozonation: photoassisted Fenton reaction: photocatalysis using TiO2). Obsolete pesticide stocks in developing countries are being packaged and shipped to developed countries for incineration. Contaminated soil can also be incinerated, but this is not practical nor affordable for small waste generators. Chemical degradation of chlorinated hydrocarbon pesticides may be amenable to dechlorination by alkali polyethylene glycol treatment, but further study is needed to make the technique practical for small waste generators. Contaminated soils may be amenable to cleanup by one of several biological treatment methods, including composting, landfarming, and bioaugmentation/ biostimulation. Composting and landfarming (which may be used in combination with biostimulation) may be the most practical of the biological methods that is immediately ready for implementation by small-scale pesticide waste generators. PMID:12666819

Felsot, Allan S; Racke, Kenneth D; Hamilton, Denis J

2003-01-01

11

Degradation of pesticides in nursery recycling pond waters.  

PubMed

Recycling or collection ponds are often used in outdoor container nursery production to capture and recycle runoff water and fertilizers. Waters in recycling ponds generally have high concentrations of nutrients, pesticides, and dissolved organic matter, as well as elevated salinity and turbidity. Little is known about pesticide degradation behavior in the unique environment of nursery recycling ponds. In this study, degradation of four commonly used pesticides diazinon, chlorpyrifos, chlorothalonil, and pendimethalin in waters from two nursery recycling ponds was investigated at an initial pesticide concentration of 50 microg/L. Results showed that the persistence of diazinon and chlorpyrifos appeared to be prolonged in recycling pond waters as compared to surface streamwaters, possibly due to decreased contribution from biotic transformation, while degradation of chlorothalonil and pendimethalin was enhanced. Activation energies of biotic degradation of all four pesticides were lower than abiotic degradation, indicating that microbial transformation was less affected by temperature than chemical transformation. Overall, the pesticide degradation capacity of recycling ponds was better buffered against temperature changes than that of surface streamwaters. PMID:16569058

Lu, Jianhang; Wu, Laosheng; Newman, Julie; Faber, Ben; Gan, Jianying

2006-04-01

12

Evaluating pesticide degradation in the environment: blind spots and emerging opportunities.  

PubMed

The benefits of global pesticide use come at the cost of their widespread occurrence in the environment. An array of abiotic and biotic transformations effectively removes pesticides from the environment, but may give rise to potentially hazardous transformation products. Despite a large body of pesticide degradation data from regulatory testing and decades of pesticide research, it remains difficult to anticipate the extent and pathways of pesticide degradation under specific field conditions. Here, we review the major scientific challenges in doing so and discuss emerging opportunities to identify pesticide degradation processes in the field. PMID:23950532

Fenner, Kathrin; Canonica, Silvio; Wackett, Lawrence P; Elsner, Martin

2013-08-16

13

Assessment of priority pesticides, degradation products, and pesticide adjuvants in groundwaters and top soils from agricultural areas of the Ebro river basin  

Microsoft Academic Search

Gas chromatography-mass spectrometry (GC\\/MS) was employed for the determination of 30 widely used pesticides including various\\u000a transformation products and alkylphenols in water and agricultural soils with the aim of assessing the impact of these compounds\\u000a in agricultural soils and the underlying aquifer. The extraction, clean-up, and analytical procedures were optimized for both\\u000a water and soil samples to provide a highly

Alain Hildebrandt; Sílvia Lacorte; Damià Barceló

2007-01-01

14

Pesticides and degradation products in groundwaters from a vineyard region: optimization of a multiresidue method based on SPE and GC-MS.  

PubMed

A reliable multiresidue method based on solid phase extraction was developed using GC-MS to determine and quantify 34 pesticides, including herbicides, fungicides, insecticides, and some of their degradation products, in groundwater in a vineyard region of La Rioja (northern Spain). Different parameters were optimized and good recoveries (65-108% range) and precisions (12-19% range) were achieved with spiked water samples for a concentration of 0.1 ?g/L. The experimental results showed an excellent linearity (r(2) > 0.99) over the 0.1-1.5 ?g/L range. The detection limits of the proposed method were 1-37 ng/L for most of the compounds studied. The methodology has been successfully applied to the analysis of groundwater samples from vineyard areas in La Rioja and the presence of pesticides, especially fungicides and herbicides, at several concentration levels was revealed. Terbuthylazine, its metabolite desethyl-terbuthylazine, and fluometuron were the pesticides most frequently detected in higher concentrations. Overall and taking into consideration the European Union maximum residue limit of pesticides in groundwater, 16 of the 34 compounds included in this study were detected in concentrations over that limit in at least one of the samples analyzed. PMID:23225715

Herrero-Hernández, Eliseo; Pose-Juan, Eva; Alvarez-Martín, Alba; Andrades, María Soledad; Rodríguez-Cruz, María Sonia; Sánchez-Martín, María J

2012-12-01

15

Results of analyses of the fungicide Chlorothalonil, its degradation products, and other selected pesticides at 22 surface-water sites in five Southern states, 2003-04  

USGS Publications Warehouse

In accordance with the mission of the U.S. Geological Survey (USGS) Toxic Substances Hydrology Program, a pesticide study was conducted during 2003-04 to determine the occurrence of the fungicide chlorothalonil and its degradation products at 22 surface-water sites in five Southern States. Water-quality samples were collected during the peanut-growing season (June-September) in 2003. During the peanut-growing season in 2004, samples were collected after large storms. An analytical method was developed at the USGS Organic Geochemistry Research Laboratory in Lawrence, Kansas, to measure chlorothalonil and its degradation products by liquid chromatography/mass spectrometry (LC/MS). Chlorothalonil was detected in 4 of the 113 surface-water samples. The primary degradation product of chlorothalonil, 4-hydroxy-chlorothalonil, was detected in 26 of the 113 samples with concentrations ranging from 0.002 to 0.930 microgram per liter. The chlorothalonil degradation products, 1-amide-4-hydroxy-chorothalonil and 1,3-diamide-chlorothalonil, were detected in one water sample each at 0.020 and 0.161 microgram per liter, respectively. The USGS Methods and Research Development Group, Lakewood, Colorado, developed a custom method for chlorothalonil using gas chromatography/mass spectrometry (GC/MS) in an effort to achieve a lower laboratory reporting level (LRL) than the USGS National Water-Quality Laboratory (NWQL) schedule 2060, which analyzes the compound chlorothalonil at a LRL of 0.035 ?g/L. The group succeeded in achieving a lower GC/MS reporting level of 0.01 ?g/L. Chlorothalonil was detected in 5 of 68 water samples analyzed using the custom GC/MS method, whereas chlorothalonil was detected in 2 of 21 water samples analyzed using NWQL schedule 2060. In addition to analysis of chlorothalonil and its degradation products, samples were analyzed using the USGS NWQL schedules 2001 and 2060 for about 114 pesticides and their degradation products. Samples also were analyzed for dissolved organic carbon, suspended sediment, and percentage of silt- and clay-sized particles. Overall, it was found that chlorothalonil was detected only infrequently and at relatively low concentrations. Chlorothalonil's major degradation product, 4-hydroxy-chlorothalonil, was detected most frequently, occurred generally at higher concentrations in water samples than did the parent fungicide, and the data from this study reaffirmed that it is the dominant degradation product of chlorothalonil in the peanut-growing environment.

Scribner, Elisabeth A.; Orlando, James L.; Battaglin, William A.; Sandstrom, Mark; Kuivila, Kathryn M.; Meyer, Michael T.

2006-01-01

16

Microbial degradation of the organophosphate pesticide, Ethion  

Microsoft Academic Search

The organophosphate pesticide, Ethion, remains a major environmental contaminant in rural Australia and poses a significant threat to environmental and public health. The aerobic degradation of Ethion by mesophilic bacteria isolated from contaminated soils surrounding disused cattle dip sites was investigated. Two isolates, identified as Pseudomonas and Azospirillum species, were capable of biodegrading Ethion when cultivated in minimal salts medium.

L. John R. Foster; Bia H. Kwan; Tony Vancov

2004-01-01

17

Photocatalytic degradation of pesticide contaminants in water  

Microsoft Academic Search

Photocatalysis has been proved to be an effective and inexpensive tool for the removal of organic and inorganic pollutants from water. Of particular interest in this context, in recent years, has been the complete photocatalytic mineralisation of a variety of pesticides into harmless products. The technique is now reaching the pre-industrial level, with several pilot plants and prototypes being operational

Suja Devipriya; Suguna Yesodharan

2005-01-01

18

Microbial degradation of an organophosphate pesticide, malathion.  

PubMed

Abstract Organophosphorus pesticide, malathion, is used in public health, residential, and agricultural settings worldwide to control the pest population. It is proven that exposure to malathion produce toxic effects in humans and other mammals. Due to high toxicity, studies are going on to design effective methods for removal of malathion and its associated compounds from the environment. Among various techniques available, degradation of malathion by microbes proves to be an effective and environment friendly method. Recently, research activities in this area have shown that a diverse range of microorganisms are capable of degrading malathion. Therefore, we aimed at providing an overview of research accomplishments on this subject and discussed the toxicity of malathion and its metabolites, various microorganisms involved in its biodegradation and effect of various environmental parameters on its degradation. PMID:23442144

Singh, Baljinder; Kaur, Jagdeep; Singh, Kashmir

2013-02-26

19

The effects of pesticide mixtures on degradation of pendimethalin in soils  

Microsoft Academic Search

Most agronomic situations involve a sequence of herbicide, fungicide, and insecticide application. On the other hand, use\\u000a of pesticidal combinations has become a standard practice in the production of many agricultural crops. One of the most important\\u000a processes influencing the behavior of a pesticide in the environment is its degradation in soil. It is known that due to several\\u000a pesticide

Maria K. Swarcewicz; Andrzej Gregorczyk

20

Pesticide runoff from greenhouse production.  

PubMed

A research has been undertaken studying pesticide residues in water from greenhouses and the use of soils and filter materials to reduce such losses. The pesticides detected in water samples collected downstream greenhouses include 9 fungicides, 5 herbicides and 4 insecticides. 10 compounds from flower and vegetable productions were frequently found to exceed environmental risk levels, and with a few exceptions the compounds were found in higher concentrations than those typically found in agricultural runoff. Some compounds were found in high concentrations (>1 microg/l) in undiluted runoff from greenhouses producing vegetables. Nutrient concentrations in the runoff were also sporadically very high, with phosphorous values varying between 0.85 and 7.4 mg P/l, and nitrogen values between 7.5 and 41.4 mg N/l. Undiluted runoff from the productions showed values of 60 mg P/l and 300 mg N/l. High values of pesticides correlated with high values of nutrients, especially P. Column experiments using a sandy agricultural soil and stock solutions of non-polar and slightly polar pesticides mixed with a complex binder and nutrients showed a significant reduction for nearly all of the compounds used, indicating that transport through soil will reduce the concentrations of the studied pesticides. The pesticide adsorption capacity of the filter materials pine bark, peat, Sphagnum moss, compost, oat straw, ferrous sand and clay soil were tested in batch and column experiments. Adsorption were studied contacting the filter materials with aqueous solutions containing greenhouse production pesticides. The batch experiments showed that pine bark and peat, both combining a high content of organic matter with a low ph, provided the highest adsorption for most of the tested pesticides. Sphagnum moss, compost and oat straw also showed high adsorption for most of the pesticides, while the mineral filters provided the lowest adsorption (30-55%). Further column experiments confirmed these results, displaying the best removal efficiency in the organic materials, varying from 200 microg/g in compost, to 500 microg/g in moss, straw and pine bark. PMID:20351415

Roseth, Roger; Haarstad, Ketil

2010-01-01

21

22. Sample handling and determination of carbamate pesticides and their transformation products in various matrices  

Microsoft Academic Search

The use of non-persistent carbamate pesticides, which often replace organochlorine and organophosphorus compounds, is increasing because of their broad spectrum of activity, high pesticide effectiveness and generally low mammalian toxicity. Suitable analytical procedures for the determination of these pesticides in a variety of environmental matrices are therefore required. Analysis of the degradation products of the carbamates is also of interest,

M. Honing; D. Barceló; B. L. M. van Baar; U. A. Th. Brinkman

1995-01-01

22

Pesticides  

MedlinePLUS

... or cause harm to crops, people, or animals. Pesticides can help get rid of them. Pesticides are not just insect killers. They also include ... mildew, germs, and more. Many household products contain pesticides. Pesticides can protect your health by killing germs, ...

23

Natural Products as Sources for New Pesticides.  

National Technical Information Service (NTIS)

Natural products as pesticides have been reviewed from several perspectives in the past, but no prior treatment has examined the impact of natural product and natural product-based pesticides on the U.S. market, as a function of new active ingredient regi...

C. L. Cantrell F. E. Dayan S. O. Duke

2012-01-01

24

Comprehensive screening study of pesticide degradation via oxidation and hydrolysis.  

PubMed

This comprehensive study focused on the reactivity of a set of 62 pesticides via oxidization by free chlorine, monochloramine, chlorine dioxide, hydrogen peroxide, ozone, and permanganate; photodegradation with UV(254); and hydrolysis at pH 2, 7, and 12. Samples were analyzed using direct injection liquid chromatography-mass spectrometry detection or gas chromatography-electron capture detection after liquid-liquid extraction. Many pesticides were reactive via hydrolysis and/or chlorination and ozonation mechanisms under typical drinking water treatment conditions, with less reactivity exhibited on average for chlorine dioxide, monochloramine, hydrogen peroxide, and UV(254). The pyrazole and organophosphorous pesticides were most reactive in general, whereas carbamates and others were less reactive. The screening study provides guidance for the pesticide/oxidation systems that are most likely to lead to degradates in water treatment and the environment. PMID:22141915

Chamberlain, Evelyn; Shi, Honglan; Wang, Tongwen; Ma, Yinfa; Fulmer, Alice; Adams, Craig

2011-12-28

25

40 CFR 165.63 - Scope of pesticide products included.  

Code of Federal Regulations, 2010 CFR

...2009-07-01 2009-07-01 false Scope of pesticide products included. 165.63 Section 165...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE MANAGEMENT AND DISPOSAL Standards for...

2009-07-01

26

40 CFR 165.63 - Scope of pesticide products included.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Scope of pesticide products included. 165.63 Section 165...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE MANAGEMENT AND DISPOSAL Standards for...

2010-07-01

27

40 CFR 168.69 - Registered export pesticide products.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Registered export pesticide products. 168.69 Section 168...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS STATEMENTS OF ENFORCEMENT...Export Policy and Procedures for Exporting Pesticides § 168.69 Registered export...

2013-07-01

28

40 CFR 168.70 - Unregistered export pesticide products.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Unregistered export pesticide products. 168.70 Section 168...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS STATEMENTS OF ENFORCEMENT...Export Policy and Procedures for Exporting Pesticides § 168.70 Unregistered export...

2013-07-01

29

Pesticide Assessment Guidelines, Subdivision G: Product Performance.  

National Technical Information Service (NTIS)

As a guideline for the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), Subdivision G provides guidance to the registrant on developing product performance data that the Agency may require to demonstrate the effectiveness of their pesticide pr...

C. Grable S. Duffy T. Ellwanger W. Audia W. Campbell

1982-01-01

30

Sorption and degradation of pesticides in nursery recycling ponds.  

PubMed

Knowledge of pesticide distribution and persistence in nursery recycling pond water and sediment is critical for preventing phytotoxicity of pesticides during water reuse and to assess their impacts to the environment. In this study, sorption and degradation of four commonly used pesticides (diazinon, chlorpyrifos, chlorothalonil, and pendimethalin) in sediments from two nursery recycling ponds was investigated. Results showed that diazinon and chlorothalonil were moderately sorbed [K(OC) (soil organic carbon distribution coefficient) from 732 to 2.45 x 10(3) mL g(-1)] to the sediments, and their sorption was mainly attributable to organic matter content, whereas chlorpyrifos and pendimethalin were strongly sorbed (K(OC) > or = 7.43 x 10(3) mL g(-1)) to the sediments, and their sorption was related to both organic matter content and sediment texture. The persistence of diazinon and chlorpyrifos was moderate under aerobic conditions (half-lives = 8 to 32 d), and increased under anaerobic conditions (half-lives = 12 to 53 d). In contrast, chlorothalonil and pendimethalin were quickly degraded under aerobic conditions with half-lives < 2.8 d, and their degradation was further enhanced under anaerobic conditions (half-lives < 1.9 d). The strong sorption of chlorpyrifos and pendimethalin by the sediments suggests that the practice of recycling nursery runoff would effectively retain these compounds in the recycling pond, minimizing their offsite movement. The prolonged persistence of diazinon and chlorpyrifos, however, implies that incidental spills, such as overflows caused by storm events, may contribute significant loads of such pesticides into downstream surface water bodies. PMID:16899750

Lu, Jianhang; Wu, Laosheng; Newman, Julie; Faber, Ben; Merhaut, Donald J; Gan, Jianying

2006-08-09

31

Pesticides  

Microsoft Academic Search

\\u000a Pesticides include plant protection and biocidal products. Many pesticides are hazardous to human health. Dermal exposure\\u000a may cause systemic toxic effects, dermatitis, or other skin effects. The use of pesticides in Europe and Northern America\\u000a is regulated for the protection of the environment and health, while severe problems are caused in developing countries. Adequate\\u000a protective equipment, working conditions, and awareness

Carola Lidén

32

Twofold role of calcined hydrotalcites in the degradation of methyl parathion pesticide  

PubMed Central

Summary Methyl parathion (MP) is a very toxic organophosphate pesticide used as a non-systematic insecticide and acaricide on many corps. As MP and its by-products are highly toxic, they have to be retained to avoid pollution of rivers and lakes. Highly efficient sorbents are hydrotalcites (HTs) (or anionic clays). We have correlated the degradation of an aqueous solution of MP at room temperature, with the basicity of the adsorbing materials. It was found that the metal composition of hydrotalcites determines both the surface electronic properties (basic or acidic) and the sorption capacity. Depending on the basic strength, some calcined hydrotalcites can catalyze the transformation of MP to p-nitrophenol (p-NP) and retain its by-products. Such a process has the advantage of being able to be carried out at room temperature and at the pH of the pesticide solution.

Fetter, Geolar; Villafuerte-Castrejon, Maria Elena; Tejeda-Cruz, Adriana; Bosch, Pedro

2011-01-01

33

Twofold role of calcined hydrotalcites in the degradation of methyl parathion pesticide.  

PubMed

Methyl parathion (MP) is a very toxic organophosphate pesticide used as a non-systematic insecticide and acaricide on many corps. As MP and its by-products are highly toxic, they have to be retained to avoid pollution of rivers and lakes. Highly efficient sorbents are hydrotalcites (HTs) (or anionic clays). We have correlated the degradation of an aqueous solution of MP at room temperature, with the basicity of the adsorbing materials. It was found that the metal composition of hydrotalcites determines both the surface electronic properties (basic or acidic) and the sorption capacity. Depending on the basic strength, some calcined hydrotalcites can catalyze the transformation of MP to p-nitrophenol (p-NP) and retain its by-products. Such a process has the advantage of being able to be carried out at room temperature and at the pH of the pesticide solution. PMID:21977419

Sampieri, Alvaro; Fetter, Geolar; Villafuerte-Castrejon, María Elena; Tejeda-Cruz, Adriana; Bosch, Pedro

2011-02-09

34

Inverse modelling for estimating sorption and degradation parameters for pesticides.  

PubMed

The leaching model PESTRAS was used to estimate sorption and degradation values for bentazone from three lysimeter datasets using the inverse modelling package PEST. Investigations were undertaken to assess the influence on calibration results of (1) values attributed to uncertain parameters not included in the calibration, and (2) starting values supplied to the inverse modelling package. Automatic calibrations with different realistic values for the Freundlich exponent n(f) yielded different combinations of K(om) and DT50. Similarly, the supply of different starting values for K(om) and DT50 revealed that different combinations of these two parameters equally calibrated PESTRAS for two of the three lysimeters. Examination of the error surface, ie the forward running of the model for different combinations of K(om) and DT50 values, and the calculation of the goodness-of-fit to the experimental data, was found useful for identifying those instances where non-uniqueness in the calibration is likely to occur. Although the derivation of sorption and degradation values through inverse modelling is expected to offer significant benefits over laboratory determinations, care should be exercised when examining values derived through this approach. Research is needed to identify data requirements for robust estimation of sorption and degradation parameters through calibration of pesticide fate models against leaching data. PMID:15382500

Dubus, Igor G; Beulke, Sabine; Brown, Colin D; Gottesbüren, Bernhard; Dieses, Angelika

2004-09-01

35

Labeling of Pesticide Products under the National Organic Program.  

National Technical Information Service (NTIS)

This notice describes how registrants can obtain Environmental Protection Agency (EPA) approval of label language indicating that all ingredients (active and inert) in a pesticide product and all uses of that pesticide meet the criteria defined in the Uni...

2002-01-01

36

40 CFR 158.2081 - Experimental use permit biochemical pesticides product chemistry data requirements table.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Experimental use permit biochemical pesticides product chemistry data requirements... DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2081 Experimental use permit biochemical pesticides product chemistry data...

2013-07-01

37

40 CFR 158.2030 - Biochemical pesticides product chemistry data requirements table.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Biochemical pesticides product chemistry data requirements...PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2030 Biochemical pesticides product chemistry data...

2013-07-01

38

40 CFR 158.2070 - Biochemical pesticides product performance data requirements.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Biochemical pesticides product performance data requirements...PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2070 Biochemical pesticides product performance data...

2013-07-01

39

Pesticide Regulation (PR) Notice 94-6. Notice to Manufacturers, Producers, Formulators, and Registrants of Pesticide Products: Pesticide Products Registered for Use on Humans to Control Lice (Pediculicides).  

National Technical Information Service (NTIS)

The notice alerts pesticide registrants to a rule issued by Food and Drug Administration (FDA) under the Federal Food, Drug and Cosmetic Act (FFDCA) establishing conditions for safe and effective use of pediculicide drug products (including pesticide prod...

1994-01-01

40

ORGANOPHOSPHORUS PESTICIDE DEGRADATION PATHWAYS DURING DRINKING WATER TREATMENT  

EPA Science Inventory

The objective of this work was to investigate organophosphorus (OP) pesticide transformation pathways as a class in the presence of aqueous chlorine. Seven priority OP pesticides were examined for their reactivity with aqueous chlorine: chlorpyrifos (CP), parathion (PA), diazino...

41

Genome Shuffling Improves Degradation of the Anthropogenic Pesticide Pentachlorophenol by Sphingobium chlorophenolicum ATCC 39723  

Microsoft Academic Search

Pentachlorophenol (PCP), a highly toxic anthropogenic pesticide, can be mineralized by Sphingobium chlorophenolicum, a gram-negative bacterium isolated from PCP-contaminated soil. However, degradation of PCP is slow and S. chlorophenolicum cannot tolerate high levels of PCP. We have used genome shuffling to improve the degradation of PCP by S. chlorophenolicum. We have obtained several strains that degrade PCP faster and tolerate

MingHua Dai; Shelley D. Copley

2004-01-01

42

40 CFR 158.2160 - Microbial pesticides product performance data requirements.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Microbial pesticides product performance data requirements...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2160...

2013-07-01

43

Leaching and degradation of 21 pesticides in a full-scale model biobed.  

PubMed

Filling and cleaning of pesticide sprayers presents a potential risk of pollution of soil and water. Three different solutions for handling sprayers have been suggested: Filling and cleaning in the field, filling and cleaning on hard surfaces with collection of the waste water, and filling and cleaning on a biobed, which is an excavation lined with clay and filled with a mixture of chopped straw, sphagnum and soil with turf on top, and with increased sorption capacity and microbial activity for degradation of the pesticides. In the present study the degradation and leaching of 21 pesticides (5 g of each) was followed in an established full-scale model biobed. Percolate was collected and analysed for pesticide residues, and the biobed material was sampled at three different depths and analysed by liquid chromatography double mass spectrometry (LC-MSMS). During the total study period of 563 days, no traces of 10 out of 21 applied pesticides were detected in the percolate (detection limits between 0.02 and 0.9 microg l(-1)) and three pesticides were only detected once and at concentrations below 2 microg l(-1). During the first 198 days before second application, 14% of the applied herbicide bentazone was detected in the leachate with maximum and mean concentrations of 445 and 172 microg l(-1), respectively. About 2% of the initial mecoprop and fluazifop dose was detected in the percolate, with mean concentrations of 23 microg l(-1), while MCPA and dimethoate had mean concentrations of 3.5 and 4.7 microg l(-1), respectively. Leachate concentrations for the remaining pesticides were generally below the detection limit (0.02-0.9 microg l(-1), below 1% of applied). Sorption studies of five pesticides showed that compounds with a low K(d) value appeared in the leachate. After 169 days, all pesticides in the biobed profile were degraded to a level below 50% of the calculated initial dose. Pesticides with K(oc) values above 100 were primarily found in the uppermost 10 cm and degraded slowest due to the low bioavailability. The 11 most degradable pesticides were all degraded such that less than 3% remained in the biobed after 169 days. Following second pesticide application of the biobed, leachate was sampled 215 and 365 days after the treatment. This showed the same pesticides to be leached out and at concentrations comparable to those of the first treatment. The same pesticides as after the first treatment were retained in the biobed. PMID:16815528

Spliid, Niels Henrik; Helweg, Arne; Heinrichson, Kirsten

2006-07-03

44

Fungal utilization of organophosphate pesticides and their degradation by Aspergillus flavus and A. sydowii in soil.  

PubMed

Fungal species were isolated which utilize organophosphate pesticides, viz. phosphorothioic (pirimiphos-methyl and pyrazophos), phosphorodithioic (dimethoate and malathion), phosphonic (lancer) and phosphoric (profenfos) acid derivatives. Pesticide degradation was studied in vitro and in vivo (soil). Aspergillus flavus, A. fumigatus, A. niger, A. sydowii, A. terreus, Emericella nidulans, Fusarium oxysporum and Penicillium chrysogenum were isolated from pesticide-treated wheat straw. The number of A. sydowii colonies was significantly promoted by 1 mmol/L pirimiphos-methyl, pyrazophos, lancer, dimethoate and malathion when used as phosphorus sources and by pirimiphos-methyl and pyrazophos when used as carbon sources. The number of A. flavus colonies increased with 0.5 mmol/L lancer and malathion used as the only carbon sources. A. sydowii, A. niger, A. flavus, E. nidulans and F. oxysporum grew on, and utilized, 5 pesticides as phosphorus source and showed more than 50% mass growth. A. sydowii, A. flavus and F. oxysporum phosphatase hydrolyzed the pesticides suggesting that these species are important pesticide degraders. A. sydowii produced higher amounts of the phosphatase than A. flavus and F. oxysporum. The enzyme was highly active against pyrazophos, lancer and malathion used as the only sources of organic phosphate. A. flavus and A. sydowii phosphatases efficiently hydrolyzed pesticides at 300 ppm in soil, the degradation at 1000 ppm was lower. Mineralization of 1000 ppm pesticides in soil amended with wheat straw was higher than in nonamended soil. All added pesticides except profenfos were degraded within 3 weeks. Lyophilized adapted biomass of A. flavus and A. sydowii could thus be used for field biodegradation of these pesticides. PMID:10489696

Hasan, H A

1999-01-01

45

Organophosphorus pesticide degradation product in vitro metabolic stability and time-course uptake and elimination in rats following oral and intravenous dosing.  

PubMed

Levels of urinary dialkylphosphates (DAPs) are currently used as a biomarker of human exposure to organophosphorus insecticides (OPs). It is known that OPs degrade on food commodities to DAPs at levels that approach or exceed those of the parent OP. However, little has been reported on the extent of DAP absorption, distribution, metabolism and excretion. The metabolic stability of O,O-dimethylphosphate (DMP) was assessed using pooled human and rat hepatic microsomes. Time-course samples were collected over 2 h and analyzed by LC-MS/MS. It was found that DMP was not metabolized by rat or pooled human hepatic microsomes. Male Sprague-Dawley rats were administered DMP at 20 mg kg(-1) via oral gavage and i.v. injection. Time-course plasma and urine samples were collected and analyzed by LC-MS/MS. DMP oral bioavailability was found to be 107 ± 39% and the amount of orally administered dose recovered in the urine was 30 ± 9.9% by 48 h. The in vitro metabolic stability, high bioavailability and extent of DMP urinary excretion following oral exposure in a rat model suggests that measurement of DMP as a biomarker of OP exposure may lead to overestimation of human exposure. PMID:21446834

Forsberg, N D; Rodriguez-Proteau, R; Ma, L; Morré, J; Christensen, J M; Maier, C S; Jenkins, J J; Anderson, K A

2011-03-29

46

Pesticides  

Center for Food Safety and Applied Nutrition (CFSAN)

... Pesticides. USDA's Pesticide Data Program. * Documents temporarily unavailable on the web. ? -. Guidance. Guidance for ... More results from www.fda.gov/food/foodborneillnesscontaminants/pesticides

47

Microbial adaption to a pesticide in agricultural soils: Accelerated degradation of 14C-atrazine in field soils from Brazil and Belgium  

Microsoft Academic Search

An increasing demand for food, feed and bioenergy, and simultaneously a decline of arable land will require an intensive agricultural production including the use of pesticides. With an increasing use of pesticides the occurrence of an accelerated degradation potential has to be assessed. Atrazine [2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine] is one of the most widely used herbicides in the world. Even though its use

Nicolai David Jablonowski; Rosane Martinazzo; Georg Hamacher; Cesare Accinelli; Stephan Köppchen; Ulrike Langen; Andreas Linden; Martina Krause; Peter Burauel

2010-01-01

48

76 FR 79171 - Pesticide Products; Receipt of Applications To Register New Uses  

Federal Register 2010, 2011, 2012, 2013

...FRL-9330-3] Pesticide Products; Receipt of Applications To Register New Uses AGENCY: Environmental...applications to register new uses for pesticide products containing currently...Applications for New Uses EPA received...register pesticide products containing...

2011-12-21

49

40 CFR 165.65 - Registrants who distribute or sell pesticide products in refillable containers.  

Code of Federal Regulations, 2013 CFR

...regarding repackaging a pesticide product into refillable containers...that repackages a pesticide product into refillable containers for...refiller has a registration for the new formulation. (3) The refiller must repackage a pesticide product only into a refillable...

2013-07-01

50

40 CFR 158.2030 - Biochemical pesticides product chemistry data requirements table.  

Code of Federal Regulations, 2010 CFR

...biochemical pesticides product chemistry. The test notes are shown...Biochemical Pesticides Product Chemistry Data Requirements Guideline...7050 UV/Visible light absorption R TGAI TGAI -- ...biochemical pesticides product chemistry and are referenced in...

2010-07-01

51

40 CFR 158.2081 - Experimental use permit biochemical pesticides product chemistry data requirements table.  

Code of Federal Regulations, 2010 CFR

...biochemical pesticides product chemistry. The test notes are shown...Biochemical Pesticides Product Chemistry Data Requirements Guideline...7050 UV/Visible light absorption R TGAI TGAI -- ...biochemical pesticides product chemistry and are referenced in...

2009-07-01

52

40 CFR 158.2081 - Experimental use permit biochemical pesticides product chemistry data requirements table.  

Code of Federal Regulations, 2010 CFR

...biochemical pesticides product chemistry. The test notes are shown...Biochemical Pesticides Product Chemistry Data Requirements Guideline...7050 UV/Visible light absorption R TGAI TGAI -- ...biochemical pesticides product chemistry and are referenced in...

2010-07-01

53

Analytical methods for pesticide residue determination in bee products.  

PubMed

Monitoring pesticide residues in honey, wax, and bees helps to assess the potential risk of these products to consumer health and gives information on the pesticide treatments that have been used on the field crops surrounding the hives. The present review seeks to discuss the basic principles and recent developments in pesticide analysis in bee products and their application in monitoring programs. Consideration is given to extraction, cleanup, chromatographic separation, and detection techniques. PMID:12233867

Fernández, M; Picó, Y; Mañes, J

2002-09-01

54

Pesticide Analysis of Bee and Bee Product Samples  

Microsoft Academic Search

Bee products possess therapeutic properties and are the source of many essential trace elements, which is why they are regarded as valuable food products. Honey bees may bring to the hive numerous contaminants deposited on the plants they visit, including pesticide without xenobiotics. The large-scale application of pesticides in agriculture and horticulture can lead to mass mortality among bees, and

?aneta Barga?ska; Jacek Namie?nik

2010-01-01

55

Degradation of pesticide residues in vineyard effluents by activated sludge treatment.  

PubMed

The study evaluates the feasibility of the degradation of thirteen pesticides by an activated sludge aerobic treatment, used for the purification of wastewater effluents produced from a winemaking process. Chemical analyses were used to determine the capacity of the treatment to eliminate the implied pollution hazard. The results show that the biological treatment of such pesticides by activated sludge is possible if a minimum adaptation period of approximately 8 days is applied. System stability is reached in 30 days. The related degradation of twelve pesticides was 97%, the exception being anilinopyrimidin. However, the sludge biomass is dispersed (the pesticides destroyed the biomass flocs) and it was necessary to add a flocculation stage to concentrate and remove the free micro-organisms by using sedimentation. PMID:19809152

Esteve, K; Poupot, C; Mietton-peuchot, M; Milisic, V

2009-01-01

56

Calculation of pesticide degradation in decaying cotton gin trash.  

PubMed

Pesticide residues were measured in stockpiled cotton gin trash (CGT) over a 2-year period. Samples were analysed by GC/MS/MS and interpretation of the results was aided by the presence of DDE residues, remnant from prior DDT use. Fourteen pesticide residues from current agricultural practice were detected in CGT. Several of these, including indoxacarb, profenofos, chlorpyrifos, propargite, bifenthrin, ethion and cyhalothrin, were more persistent than expected on the basis of published data for soil dissipation. The results showed a complex pattern of pesticide residue decay over time because of the simultaneous decomposition of the CGT matrix. PMID:18651089

Crossan, Angus N; Kennedy, Ivan R

2008-07-24

57

Degradation of pesticides in soil as influenced by the presence of hydrolysis metabolites  

Microsoft Academic Search

The degradation of 8 pesticides was evaluated in a soil pretreated with their respective hydrolysis metabolites. 2,4?Dichlorophenol, p?nitrophenol, and salicylic acid conditioned the soil for enhanced degradation of 2,4?dichlorophenoxyacetic acid (2,4?D), parathion, and isofenphos, respectively. Repeated application of carbofuran phenol, 2?isopropyl?4?methyl?6?hydroxypyrimidine, methyl phenyl sulfone, thiophenol, isopropyl salicylate, and 2,4,5?trichlorophenol had no effect on the rate of degradation of their parent

L. Somasundaram; J. R. Coats; K. D. Racke

1989-01-01

58

40 CFR 158.2030 - Biochemical pesticides product chemistry data requirements table.  

Code of Federal Regulations, 2010 CFR

...product chemistry data requirements table. 158.2030 Section 158.2030 Protection of Environment ENVIRONMENTAL PROTECTION...REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2030 Biochemical pesticides product chemistry data...

2009-07-01

59

Combining chemical and isotopic measurements to estimate pesticide degradation rates in a fractured-rock aquifer  

NASA Astrophysics Data System (ADS)

Encouraged by new regulatory requirements for pesticide registration and authorization, the transport and environmental fate of these compounds in the different environmental compartments has been studied extensively. Degradation rates vary widely depending on hydraulic and chemical characteristics, with the strongest degradation usually occuring in the topsoil. Nonetheless, significant pesticide attenuation may still take place during transport in the aquifer, since residence times are generally much longer than in the soil. Ideally, pesticide transformation in the aquifer needs to be determined under real field conditions. Mass balance calculations however are complicated by the fact that the initial pesticide mass leached from the soil is often not known precisely enough. In this study, isotopic and classical pesticide concentration measurements were combined with groundwater dating techniques to assess the degradation rate of atrazine and its metabolite desethylatrazine in a fractured sandstone. The mass balance problem was solved by introducing the desethylatrazine to atrazine ratio, a relative measure which was used to quantify the advancement of atrazine degradation with increasing transport time in the subsurface. The extent of transformation of the parent compound was finally estimated from the shift in the isotopic signal between soil application and the outlet of the groundwater system.

Farlin, Julien; Gallé, Tom; Bayerle, Michael; Pittois, Denis; El-Khabbaz, Hassanya; Schreglmann, Kathrin; Höche, Martina; Elsner, Martin

2013-04-01

60

Pesticides.  

ERIC Educational Resources Information Center

|This review is devoted to methods for the determination of residues of pesticides and some related industrial chemicals. Topics include: residue methods, sampling, chromatography, organochlorine pesticides, organophosphorus pesticides, carbamate insecticides, herbicides, fungicides, pyrethrins, fumigants, and related chemicals. (MVL)|

Sherma, Joseph

1989-01-01

61

Pesticides removal in the process of drinking water production.  

PubMed

The aim of this research work was to study the effectiveness of the treatments commonly used in drinking water plants in Spain to degrade 44 pesticides systematically detected in the Ebro River Basin. The pesticides studied are: alachlor, aldrin, ametryn, atrazine, chlorfenvinfos, chlorpyrifos, pp'-DDD, op'-DDE, op'-DDT, pp'-DDT, desethylatrazine, 3,4-dichloroaniline, 4,4'-dichlorobenzophenone, dicofol, dieldrin, dimethoate, diuron, alpha-endosulphan, endosulphan-sulphate, endrin, alpha-HCH, beta-HCH, gamma-HCH, delta-HCH, heptachlor, heptachlor epoxide A, heptachlor epoxide B, hexachlorobenzene, isodrin, 4-isopropylaniline, isoproturon, metholachlor, methoxychlor, molinate, parathion methyl, parathion ethyl, prometon, prometryn, propazine, simazine, terbuthylazine, terbutryn, tetradifon and trifluralin. The techniques applied are: preoxidation by chlorine or ozone, chemical precipitation with aluminium sulphate and activated carbon adsorption. Oxidation by chlorine removes 60% of the studied pesticides, although combining this technique with a coagulation-flocculation-decantation process is more effective. The disadvantage of this treatment is the formation of trihalomethanes. Oxidation by ozone removes 70% of the studied pesticides. Although combination with a subsequent coagulation-flocculation-decantation process does not improve the efficiency of the process, combination with an activated-carbon absorption process gives rise to 90% removal of the studied pesticides. This technique was found to be the most efficient among the techniques studied for degrading the majority of the studied pesticides. PMID:18023468

Ormad, M P; Miguel, N; Claver, A; Matesanz, J M; Ovelleiro, J L

2007-11-26

62

ORGANOPHOSPHATE PESTICIDE DEGRADATION UNDER DRINKING WATER TREATMENT CONDITIONS  

EPA Science Inventory

The Food Quality Protection Act (FQPA) of 1996 requires that all tolerances for pesticide chemical residuals in or on food be considered for anticipated exposure. Drinking water is considered a potential pathway for dietary exposure and there is reliable monitoring data for the ...

63

Integration of Solar Photocatalysis and Membrane Bioreactor for Pesticides Degradation  

Microsoft Academic Search

Wastewater containing recalcitrant contaminants as pesticides can be treated by a coupled system which consists of a solar photo-Fenton pretreatment followed by a biological oxidation process. Membrane bioreactor technology (MBR) is particularly suitable for advanced biological treatment of wastewater containing biorecalcitrant compounds and shows a variety of advantages that make it a good alternative to be coupled with photo-Fenton, especially

J. L. Casas López; A. Cabrera Reina; E. Ortega Gómez; M. M. Ballesteros Martín; S. Malato Rodríguez; J. A. Sánchez Pérez

2010-01-01

64

ORGANOPHOSPHATE PESTICIDE DEGRADATION UNDER DRINKING WATER TREATMENT CONDITIONS  

EPA Science Inventory

Chlorpyrifos (CP) was used as a model compound to develop experimental methods and prototype modeling tools to forecast the fate of organophosphate (OP) pesticides under drinking water treatment conditions. CP was found to rapidly oxidize to chlorpyrifos oxon (CPO) in the presen...

65

40 CFR 152.15 - Pesticide products required to be registered.  

Code of Federal Regulations, 2011 CFR

... 24 2011-07-01 2011-07-01 false Pesticide products required to be registered. 152.15...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION PROCEDURES...

2011-07-01

66

40 CFR 165.65 - Registrants who distribute or sell pesticide products in refillable containers.  

Code of Federal Regulations, 2010 CFR

...2009-07-01 false Registrants who distribute or sell pesticide products in refillable containers. 165.65...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE MANAGEMENT AND DISPOSAL Standards for...

2009-07-01

67

40 CFR 165.67 - Registrants who distribute or sell pesticide products to refillers for repackaging.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Registrants who distribute or sell pesticide products to refillers for repackaging. 165...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE MANAGEMENT AND DISPOSAL Standards for...

2011-07-01

68

40 CFR 165.65 - Registrants who distribute or sell pesticide products in refillable containers.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Registrants who distribute or sell pesticide products in refillable containers. 165.65...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE MANAGEMENT AND DISPOSAL Standards for...

2010-07-01

69

40 CFR 165.67 - Registrants who distribute or sell pesticide products to refillers for repackaging.  

Code of Federal Regulations, 2010 CFR

...2009-07-01 false Registrants who distribute or sell pesticide products to refillers for repackaging. 165...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE MANAGEMENT AND DISPOSAL Standards for...

2009-07-01

70

40 CFR 165.67 - Registrants who distribute or sell pesticide products to refillers for repackaging.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Registrants who distribute or sell pesticide products to refillers for repackaging. 165...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE MANAGEMENT AND DISPOSAL Standards for...

2012-07-01

71

40 CFR 152.15 - Pesticide products required to be registered.  

Code of Federal Regulations, 2012 CFR

... 25 2012-07-01 2012-07-01 false Pesticide products required to be registered. 152.15...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION PROCEDURES...

2012-07-01

72

9 CFR 318.16 - Pesticide chemicals and other residues in products.  

Code of Federal Regulations, 2013 CFR

...General § 318.16 Pesticide chemicals and other residues in products...ingredients. Residues of pesticide chemicals, food additives and color additives...bear or contain any pesticide chemical, food additives, or color...

2013-01-01

73

40 CFR 165.67 - Registrants who distribute or sell pesticide products to refillers for repackaging.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Registrants who distribute or sell pesticide products to refillers for repackaging. 165...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE MANAGEMENT AND DISPOSAL Standards for...

2013-07-01

74

40 CFR 168.66 - Labeling of pesticide products and devices intended solely for export.  

Code of Federal Regulations, 2013 CFR

... 2013-07-01 false Labeling of pesticide products and devices intended solely...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS STATEMENTS OF ENFORCEMENT...Export Policy and Procedures for Exporting Pesticides § 168.66 Labeling of...

2013-07-01

75

40 CFR 152.15 - Pesticide products required to be registered.  

Code of Federal Regulations, 2013 CFR

... 25 2013-07-01 2013-07-01 false Pesticide products required to be registered. 152.15...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION PROCEDURES...

2013-07-01

76

Photocatalytic degradation of pesticide pyridaben on TiO 2 particles  

Microsoft Academic Search

The TiO2 photoassisted degradation of pesticide pyridaben has been examined in acetonitrile\\/water suspensions under UV light irradiation mainly at wavelength longer than 360nm. To distinguish from the accompanying photolytic phenomenon, the kinetics of direct photolytic and photocatalytic degradation of pyridaben in TiO2 suspensions were studied by two different UV wavelength irradiations (??300nm and ??360nm). The results manifested that the photolysis

Xinle Zhu; Chunwei Yuan; Yanchu Bao; Jihong Yang; Yizu Wu

2005-01-01

77

75 FR 74713 - Product Cancellation Order for Certain Pesticide Registrations; Correction  

Federal Register 2010, 2011, 2012, 2013

...document is being issued to rescind the cancellation of Sergeant's Pet Care Products' pesticide product, EPA Reg. No. 2517-79...notice do? This notice rescinds the cancellation of Sergeant's Pet Care Products' pesticide product, EPA Reg. No....

2010-12-01

78

Heterogeneous Photocatalytic Degradation of Selected Organophosphate Pesticides: A Review  

Microsoft Academic Search

This review is an attempt to summarize the research carried out on heterogeneous photocatalytic treatment of selected organophosphates present invariably in shallow and ground water supplies. The basic principle of semiconductor mediated photocatalytic process, experimental conditions used, optimization of the parameters affecting the efficiency and degradation mechanism has been explained. The kinetics of organophosphate degradation and the analytical techniques for

Dhiraj Sud; Paramjeet Kaur

2011-01-01

79

Degradation of terbuthylazine, difenoconazole and pendimethalin pesticides by selected fungi cultures.  

PubMed

Contamination of waters by xenobiotic compounds such as pesticides presents a serious environmental problem with substantial levels of pesticides now contaminating European water resources. The aim of this work was to evaluate the ability of the fungi Fusarium oxysporum, Aspergillus oryzae, Lentinula edodes, Penicillium brevicompactum and Lecanicillium saksenae, for the biodegradation of the pesticides terbuthylazine, difenoconazole and pendimethalin in batch liquid cultures. These pesticides are common soil and water contaminants and terbuthylazine is considered the most persistent triazine herbicide in surface environments. P. brevicompactum and L. saksenae were achieved by enrichment, isolation and screening of fungi capable to metabolize the pesticides studied. The isolates were obtained from two pesticide-primed materials (soil and biomixture). Despite the relatively high persistence of terbuthylazine, the results obtained in this work showed that the fungi species studied have a high capability of biotransformation of this xenobiotic, comparatively the results obtained in other similar studies. The highest removal percentage of terbuthylazine from liquid medium was achieved with A. oryzae (~80%), although the major biodegradation has been reached with P. brevicompactum. The higher ability of P. brevicompactum to metabolize terbuthylazine was presumably acquired through chronic exposure to contamination with the herbicide. L. saksenae could remove 99.5% of the available pendimethalin in batch liquid cultures. L. edodes proved to be a fungus with a high potential for biodegradation of pesticides, especially difenoconazole and pendimethalin. Furthermore, the metabolite desethyl-terbuthylazine was detected in L. edodes liquid culture medium, indicating terbuthylazine biodegradation by this fungus. The fungi strains investigated could prove to be valuable as active pesticide-degrading microorganisms, increasing the efficiency of biopurification systems containing wastewaters contaminated with the xenobiotics studied or compounds with similar intrinsic characteristics. PMID:22878100

Pinto, A P; Serrano, C; Pires, T; Mestrinho, E; Dias, L; Teixeira, D Martins; Caldeira, A T

2012-08-09

80

[Organochlorine pesticide residues in raw and roasted coffee and their degradation during the roasting process].  

PubMed

An analysis method for determination of organochloro pesticides in green and roasted coffees was developed. 17 Arabica and 2 Robusta coffees originating from 11 countries were investigated. With the exception of two samples the amounts of pesticide residues found in the green coffees were considerably lower than the amounts permitted, according to the "Höchstmengenverordnung". In 2 coffees no residues were detectable. The residues were reduced to insignificant amounts during the roasting process. The degradation rates ranged from 85% to 100%. Since the residues detected in all of the roasted coffees were insignificant, no further investigation of the corresponding beverages was necessary. PMID:6485555

Cetinkaya, M; von Düszeln, J; Thiemann, W; Silwar, R

1984-07-01

81

40 CFR 158.2030 - Biochemical pesticides product chemistry data requirements table.  

Code of Federal Regulations, 2012 CFR

...false Biochemical pesticides product chemistry data requirements table. 158.2030...2030 Biochemical pesticides product chemistry data requirements table. (a) General...use this table to determine the product chemistry data requirements for a...

2012-07-01

82

40 CFR 158.2081 - Experimental use permit biochemical pesticides product chemistry data requirements table.  

Code of Federal Regulations, 2011 CFR

...permit biochemical pesticides product chemistry data requirements table. 158.2081...permit biochemical pesticides product chemistry data requirements table. (a) General...use this table to determine the product chemistry data requirements for a...

2011-07-01

83

40 CFR 158.2081 - Experimental use permit biochemical pesticides product chemistry data requirements table.  

Code of Federal Regulations, 2012 CFR

...permit biochemical pesticides product chemistry data requirements table. 158.2081...permit biochemical pesticides product chemistry data requirements table. (a) General...use this table to determine the product chemistry data requirements for a...

2012-07-01

84

40 CFR 158.2030 - Biochemical pesticides product chemistry data requirements table.  

Code of Federal Regulations, 2011 CFR

...false Biochemical pesticides product chemistry data requirements table. 158.2030...2030 Biochemical pesticides product chemistry data requirements table. (a) General...use this table to determine the product chemistry data requirements for a...

2011-07-01

85

Pesticides  

MedlinePLUS

... pesticides are regulated by the U.S. Department of Agriculture. This agency for how pesticides are applied during ... NOT place food scraps in the garden for birds or possums. Throw out any food left in ...

86

Investigation of the photocatalytic degradation of organochlorine pesticides on a nano-TiO 2 coated film  

Microsoft Academic Search

The photocatalytic degradation of organochlorine pesticides including ?-, ?-, ?-, ?-hexachlorobenzene (BHC), dicofol and cypermethrin were carried out on a nano-TiO2 coated films under UV irradiation in the air. The photocatalytic conditions, including the amount of TiO2, irradiation time and the intensity of light were optimized. The pesticides were most effectively degraded under the condition of 2.24mg\\/cm2 on TiO2 film

Binbin Yu; Jingbin Zeng; Lifen Gong; Maosheng Zhang; Limei Zhang; Xi Chen

2007-01-01

87

Degradation of Pesticides in Subsurface Soils, Unsaturated Zone—a Review Of Methods and Results  

Microsoft Academic Search

Methods and results from degradation studies in subsoils, unsaturated zone, were reviewed for mecoprop, 2,4-D, atrazine, alachlor, aldicarb, carbofuran, linuron, oxamyl, methomyl, MCPA, dichlorprop, monochlorprop, dichlorphenol, TCA, parathion, metribuzin, metolachlor and fenamiphos.Most of the investigations were laboratory studies where small soil samples were sieved and pesticides were added in concentrations from 0.5-5 ?g.g. A few of the studies mentioned the

I. S. Fomsgaard

1995-01-01

88

Biodegradation of pesticides in soil: Rapid induction of carbamate degrading factors after carbofuran treatment  

Microsoft Academic Search

Degradation rates of carbofuran were greatly increased by a single 10 ppm carbofuran pre?treatment of a sandy loam soil with no previous history of pesticide use. Thorough mixing was required to homogeneously distribute the active agent(s). Numbers of bacteria and fungi were not affected by the pre?treatment, but the drastic reduction in activity produced by heat sterilization, freezing or drying

C. R. Harris; R. A. Chapman; C. M. Tu

1984-01-01

89

An optical instrument to test pesticide residues in agricultural products  

NASA Astrophysics Data System (ADS)

Pesticide is one of the indispensability materials in modern agricultural management, however the excessive use of pesticides has threatened the ecological environment and people's health. This paper introduced an optical instrument to test the pesticide residues in agricultural products based on the inhibition rate of organophosphates against acrtyl-cholinesterase (AchE). The instrument consists mainly of a solid light source with 410nm wavelength, a sampling container, an optical sensor, a temperature sensor, and a MCU based data acquisition board. The light illuminated through the liquid in the sampling container, and the absorptivity was determined by the amount of the pesticide residues in the liquid. This paper involves the design of optical testing system, the data acquisition and calibration of the optical sensor, the design of microcontroller-based electrical board. Tests were done to reveal the affection of temperature and reacting time on AchE, to establish the relationship between the amount of methamidophos and dichlorvos with AchE. The results showed that the absorption rate was related to the pesticide residues and it could be concluded that the pesticide residues exceeded the normal level when the inhibition rate was over 50 percent. The instrument has potential application in vegetable markets.

Qiu, Zhengjun; Zheng, Wenzhong; Fang, Hui; He, Yong

2005-11-01

90

Input dynamics of pesticide transformation products into surface water  

NASA Astrophysics Data System (ADS)

Some pesticide transformation products have been observed to occur in higher concentrations and more frequently than the parent active pesticide in surface water and groundwater. These products are often more mobile and sometimes more stable than the parent pesticide. If they also represent the major product into which the parent substance is transformed, these transformation products may dominate observed pesticide occurrences in surface water and groundwater. Their potential contribution to the overall risk to the aquatic environment caused by the use of the parent pesticide should therefore not be neglected in chemical risk and water quality assessments. The same is true for transformation products of other compound classes that might reach the soil environment, such as veterinary pharmaceuticals. However, the fate and input pathways of transformation products of soil-applied chemicals into surface water are not yet well understood, which largely prevents their appropriate inclusion into chemical risk and water quality assessments. Here, we studied whether prioritization methods based on available environmental fate data from pesticide registration dossiers in combination with basic fate models could help identify transformation products which can be found in relevant concentrations in surface and groundwater and which should therefore be included into monitoring programs. A three-box steady state model containing air, soil, and surface water compartments was used to predict relative inputs of pesticide transformation products into surface waters based on their physico-chemical and environmental fate properties. The model predictions were compared to monitoring data from a small Swiss river located in an intensely agricultural catchment (90 km2) which was flow-proportionally sampled from May to October 2008 and screened for 74 pesticides as well as 50 corresponding transformation products. Sampling mainly occurred during high discharge, but additional samples during baseflow conditions were also taken. The analytical measurements included solid phase extraction, liquid chromatography and high resolution mass spectrometry (SPE-LC-HR-MS/MS). Quantification was achieved using reference standards and internal standards. Besides the well-known transformation products of triazine and chloroacetanilide herbicides, transformation products of other compound classes such as azoxystrobin acid (from azoxystrobin, strobilurin fungicide), chloridazon-desphenyl and chloridazon-methyl-desphenyl (from chloridazon, pyridazinone herbicide), and metamitron-desamino (from metamitron, triazinone herbicide) were analyzed in surface water. For a selection of widely used pesticides in the catchment, modelled ratios of transformation product versus parent pesticide concentrations were compared to the measured concentration ratios in the river for the application period and for two 2-month periods following application. Concentration ratios agreed within a factor of 10 for all pairs of parent pesticides and transformation products, and for all seasons, with a single exception. The ratio of chloridazon-desphenyl to chloridazon was under-predicted by a factor of approximately 20. The data revealed that chloridazon-desphenyl was also found in elevated concentrations in all baseflow samples, indicating its presence in the groundwater component of the catchment. The same was true for other transformation products (e.g., metamitron-desamino, chloridazon-methly-desphenyl, metolachlor-ESA), but to a lesser degree. Based on baseflow separation of the hydrograph, the concentration ratio estimation model was supplemented with an additional baseflow component. The concentrations in the baseflow component were estimated with a simple leaching relationship that was compared against measured baseflow concentrations and groundwater findings in Switzerland. The final model yielded good agreement for all compounds and is therefore deemed suitable for prioritization of transformation products with a relevant exposure potential. It also clearly indicated the contr

Kern, Susanne; Singer, Heinz; Hollender, Juliane; Schwarzenbach, René P.; Fenner, Kathrin

2010-05-01

91

PR Notice 93-5. Notice to Manufacturers, Formulators, Distributors, and Registrants of Pesticide Products.  

National Technical Information Service (NTIS)

The notice alerts pesticide registrants to a recently issued rule under the Clean Air Act (CAA) requiring a warning statement on products (including pesticide products) manufactured with or containing Class I ozone depleting substances, including chlorofl...

1993-01-01

92

PR Notice 93-4. Notice to Manufacturers, Formulators, Distributors, and Registrants of Pesticide Products.  

National Technical Information Service (NTIS)

The notice alerts pesticide registrants to a recently issued rule under the Clean Air Act (CAA) banning distribution and sale of aerosol and pressurized products, including pesticide products, that contain chlorofluorocarbons (CFCs). In addition, the noti...

1993-01-01

93

62 FR 60566 - National Emission Standards for Hazardous Air Pollutants Pesticide Active Ingredient Production  

Federal Register 2010, 2011, 2012, 2013

...National Emission Standards for Hazardous Air Pollutants Pesticide Active Ingredient Production...National Emission Standards for Hazardous Air Pollutants Pesticide Active Ingredient Production...national emission standards for hazardous air pollutants (NESHAP) for the...

1997-11-10

94

78 FR 10167 - Pesticide Products; Registration Applications for a New Active Ingredient  

Federal Register 2010, 2011, 2012, 2013

...Registration Applications for a New Active Ingredient AGENCY: Environmental Protection...register pesticide products containing an active ingredient not included in any currently...register pesticide products containing an active ingredient not included in any...

2013-02-13

95

Biodegradation of pesticides. (Latest citations from the Biobusiness data base). Published Search  

SciTech Connect

The bibliography contains citations concerning the biological degradation of pesticides. Pesticides such as malathion, parathion and DDT, organophosphates and carbamates, herbicides, fungicides, and rodenticides are examined. Coverage includes the isolation of enzymes specifically able to degrade pesticides, field studies of natural degradation and migration of pesticides, and test tube examination of microbial organisms with the ability to digest pesticides. Degradation products, effects of available nutrients on microbial degradation, and pesticide resistance in natural ecosystems are also discussed. (Contains a minimum of 190 citations and includes a subject term index and title list.)

Not Available

1992-05-01

96

Photocatalytic degradation of pesticides and bio-molecules in water.  

PubMed

Two approaches are suggested for the acceleration of the photocatalytic oxidation of organic contaminants of water: acceleration by oxidants and photo-enhancement by dyes. These processes were examined with several substances: two widely applied herbicides, bromacil (a uracil) and metribuzin (a triazine), and three proteins, studied as models of biocontaminated waters. The effects of oxygen and hydrogen peroxide indicated two different reaction patterns of photo-oxidation of the herbicides. With metribuzin, oxygen had a pronounced effect on the rate of photo-oxidation, while the influence of hydrogen peroxide was quite moderate; with bromacil, oxygen had a limited effect on the rate of photo-oxidation, which however was considerably enhanced by hydrogen peroxide. Acceleration of the photo-catalytic oxidation of colourless refractory contaminants by photo-excited dye was observed. Both UV and visible light were required for the enhanced decomposition. The mechanism of the reaction seems to involve a combination of oxidation by hydroxyl radicals, via the hole-electron semiconductor route, with subsequent oxidation of photo-intermediates by singlet oxygen formed by dye sensitization. The TiO2-photocatalyzed oxidation of proteins (albumin, ovalbumin and gamma-globulin) showed the susceptibility of proteins to photocleavage and of the amino acids to photocatalytic degradation. Tyrosine was the most sensitive, while the degradation of the aliphatic amino acids Gly and Asp was slow. PMID:12449534

Muszkat, Lea; Feigelson, Leonid; Bir, Lena; Muszkat, Karol A

2002-11-01

97

Atrazine degradation by anodic Fenton treatment  

Microsoft Academic Search

Anodic Fenton treatment (AFT), an hydroxyl radical oxidation process recently developed for the degradation of aqueous pesticide waste, was applied to the degradation of atrazine, seven degradation products, and a formulated atrazine product. Using AFT, degradation of the parent compound occurred in 3min. The concentration profiles of seven degradation products formed during treatment were measured, and degradation pathways are proposed

David A Saltmiras; Ann T Lemley

2002-01-01

98

Pesticide nonextractable residue formation in soil: insights from inverse modeling of degradation time series.  

PubMed

Formation of soil nonextractable residues (NER) is central to the fate and persistence of pesticides. To investigate pools and extent of NER formation, an established inverse modeling approach for pesticide soil degradation time series was evaluated with a Monte Carlo Markov Chain (MCMC) sampling procedure. It was found that only half of 73 pesticide degradation time series from a homogeneous soil source allowed for well-behaved identification of kinetic parameters with a four-pool model containing a parent compound, a metabolite, a volatile, and a NER pool. A subsequent simulation indeed confirmed distinct parameter combinations of low identifiability. Taking the resulting uncertainties into account, several conclusions regarding NER formation and its impact on persistence assessment could nonetheless be drawn. First, rate constants for transformation of parent compounds to metabolites were correlated to those for transformation of parent compounds to NER, leading to degradation half-lives (DegT50) typically not being larger than disappearance half-lives (DT50) by more than a factor of 2. Second, estimated rate constants were used to evaluate NER formation over time. This showed that NER formation, particularly through the metabolite pool, may be grossly underestimated when using standard incubation periods. It further showed that amounts and uncertainties in (i) total NER, (ii) NER formed from the parent pool, and (iii) NER formed from the metabolite pool vary considerably among data sets at t??, with no clear dominance between (ii) and (iii). However, compounds containing aromatic amine moieties were found to form significantly more total NER when extrapolating to t?? than the other compounds studied. Overall, our study stresses the general need for assessing uncertainties, identifiability issues, and resulting biases when using inverse modeling of degradation time series for evaluating persistence and NER formation. PMID:22891938

Loos, Martin; Krauss, Martin; Fenner, Kathrin

2012-09-05

99

Degradation and adsorption of pesticides in compost-based biomixtures as potential substrates for biobeds in southern Europe.  

PubMed

Biobeds have been used in northern Europe for minimizing point source contamination of water resources by pesticides. However, little is known regarding their use in southern Europe where edaphoclimatic conditions and agriculture practices significantly differ. A first step toward their adaptation in southern Europe is the use of low-cost and easily available substrates as biomixture components. This study investigated the possibility of replacing peat with agricultural composts in the biomixture. Five composts from local substrates including olive leaves, cotton crop residues, cotton seeds, spent mushroom substrate, and commercial sea wrack were mixed with topsoil and straw (1:1:2). Degradation of a mixture of pesticides (dimethoate, indoxacarb, buprofezin, terbuthylazine, metribuzin, metalaxyl-M, iprodione, azoxystrobin) at two dose rates was tested in the compost biomixtures (BX), in corresponding peat biomixtures (OBX), and in soil. Adsorption-desorption of selected pesticides were also studied. Pesticide residues were determined by gas chromatography with nitrogen-phosphorus detector, except indoxacarb, which was determined with a microelectron capture detector. Overall, BX degraded the studied pesticides at rates markedly higher than those observed in soil and OBX, in which the slowest degradation rates were evident. Overall, the olive leaf compost biomixture showed the highest degradation capacity. Adsorption studies showed that OBX and BX had higher adsorption affinity compared to soil. Desorption experiments revealed that pesticide adsorption in biomixtures was not entirely reversible. The results suggest that substitution of peat with local composts will lead to optimization of the biobed system for use in Mediterranean countries. PMID:20666446

Karanasios, Evangelos; Tsiropoulos, Nikolaos G; Karpouzas, Dimitrios G; Ehaliotis, Constantinos

2010-07-28

100

Pesticide Use in United States Citrus Production, 1977.  

National Technical Information Service (NTIS)

Pesticide use in citrus production for 1977 was estimated for the three citrus producing regions in the United States (Florida, Texas, and California/Arizona). Citrus growers used an estimated 38.4 million pounds of active ingredient in approximately 8.2 ...

J. J. Haydu

1981-01-01

101

Transport and degradation of pesticides in a biopurification system under variable flux Part II: A macrocosm study.  

PubMed

Transport of bentazone, isoproturon, linuron, metamitron and metalaxyl were studied under three different flows in macrocosms. The aim was to verify the observations from Part I of the accompanying paper, with an increase in column volume and decrease in chemical and hydraulic load. Very limited breakthrough occurred in the macrocosms for all pesticides, except bentazone, at all flows. From batch degradation experiments, it was observed that the lag time of metamitron and linuron decreased drastically in time for all flows, indicating a growth in the pesticide degrading population. This in contrast to isoproturon and metalaxyl, where an increase in lag time could be observed in time for all flows. From the batch degradation experiments, it could be concluded that the influence of flow on the lag time was minimal and that the inoculation of the pesticide-primed soil had a little surplus value on degradation. PMID:20696511

De Wilde, Tineke; Spanoghe, Pieter; Ryckeboer, Jaak; Jaeken, Peter; Springael, Dirk

2010-08-08

102

Photocatalytic degradation of pesticide pyridaben in suspension of TiO 2: identification of intermediates and degradation pathways  

Microsoft Academic Search

Photocatalytic degradation of pyridaben under UV irradiation has been investigated in acetonitrile\\/water solution containing TiO2 particles. The primary degradation of the pollutant followed the Langmuir–Hinshelwood model with kinetic constant k, 4.3×10?5mol\\/lmin and equilibrium adsorption constant K, 3.1×103l\\/mol. Eight kinds of degradation products (DPs) were identified by GC–MS in the process of reaction and some of them were further confirmed by

Xinle Zhu; Xiaogang Feng; Chunwei Yuan; Xiaomei Cao; Jinheng Li

2004-01-01

103

Photocatalytic degradation of pesticides in pure water and a commercial agricultural solution on TiO2 coated media.  

PubMed

Heterogeneous photocatalysis of pesticides is an effective process for removing pesticides from pure water. With a view to treating real agricultural effluents, this paper deals with the degradation of the chlortoluron and cyproconazole pesticides in pure water and the treatment of commercial solutions by photocatalysis on TiO2 coated media. The process was effective in degrading and mineralizing the pesticides. The changes of the fate of heteroatoms showed that during irradiation of the chlortoluron and cyproconazole, NH4+ and NO3(-) ions were produced. A release of chloride ions was observed from the beginning of the irradiation and stoichiometry was achieved. The photodegradation of chlortoluton and cyproconazole in commercial solutions was studied. For the degradation of chlortoluton in a commercial solution, the mineralization was completely achieved whereas in the case of the commercial cyproconazole solution, the degradation kinetic was lower. These results highlight the fact that the chemical nature of the additives in the commercial pesticide solutions does significantly affect the degradation yield of the target compound by photocatalysis. PMID:17709129

Lhomme, L; Brosillon, S; Wolbert, D

2007-08-20

104

Planktonic versus biofilm catabolic communities: importance of the biofilm for species selection and pesticide degradation.  

PubMed

Chloropropham-degrading cultures were obtained from sludge and soil samples by using two different enrichment techniques: (i) planktonic enrichments in shaken liquid medium and (ii) biofilm enrichments on two types of solid matrixes (plastic chips and gravel). Denaturing gradient gel electrophoresis fingerprinting showed that planktonic and biofilm cultures had a different community composition depending on the presence and type of added solid matrix during enrichment. This was reflected in the unique chloropropham-degrading species that could be isolated from the different cultures. Planktonic and biofilm cultures also differed in chloropropham-degrading activity. With biofilm cultures, slower chloropropham removal was observed, but with less build-up of the toxic intermediate 3-chloroaniline. Disruption of the biofilm architecture resulted in degradation characteristics shifting toward those of the free suspensions, indicating the importance of a well-established biofilm structure for good performance. These results show that biofilm-mediated enrichment techniques can be used to select for pollutant-degrading microorganisms that like to proliferate in a biofilm and that cannot be isolated using conventional shaken-liquid procedures. Furthermore, the influence of the biofilm architecture on the pesticide degradation characteristics suggests that for bioaugmentation the use of biofilm catabolic communities might be a proficient alternative to using planktonic freely suspended cultures. PMID:21602394

Verhagen, Pieter; De Gelder, Leen; Hoefman, Sven; De Vos, Paul; Boon, Nico

2011-05-20

105

Effects of single pesticides and binary pesticide mixtures on estrone production in H295R cells.  

PubMed

The aim of the present study was to determine whether the human adrenocortical carcinoma cell line H295R can be used as an in vitro test system to investigate the effects of binary pesticide combinations on estrone production as biological endpoint. In the first step ten pesticides selected according to a tiered approach were tested individually. The anilinopyrimidines cyprodinil and pyrimethanil as well as the dicarboximides iprodione and procymidone increased estrone concentration, while the triazoles myclobutanil and tebuconazole as well as the strobilurins azoxystrobin and kresoxim-methyl decreased estrone concentration in the supernatant of H295R cells. The N-methylcarbamate methomyl did not show any effects, and the phthalimide captan reduced estrone concentration unspecifically due to its detrimental impact on cellular viability. When cyprodinil and pyrimethanil, which belong to the same chemical group and increase estrone production, were combined, in most of the cases the overall effect was solely determined by the most potent compound in the mixture (i.e., cyprodinil). When cyprodinil and procymidone, which belong to different chemical groups but increase estrone production, were combined, in most cases an additive effect was observed. When cyprodinil, which increased estrone production, was combined with either myclobutanil or azoxystrobin, which decreased estrone production, the overall effect of the mixture was in most cases either entirely determined by myclobutanil or at least partially modulated by azoxystrobin. In conclusion, H295R cells appear to be an adequate in vitro test system to study the effect of combining two pesticides affecting estrone production. PMID:23708528

Prutner, Wiebke; Nicken, Petra; Haunhorst, Eberhard; Hamscher, Gerd; Steinberg, Pablo

2013-05-26

106

Field-Scale Variation in Microbial Activity and Soil Properties in Relation to Mineralization and Sorption of Pesticides in a Sandy Soil  

Microsoft Academic Search

Pesticides applied to agricultural soils are subject to environmental concerns because leaching to groundwater reservoirs and aquatic habitats may occur. Knowledge of fi eld variation of pesticide-related parameters is required to evaluate the vulnerability of pesticide leaching. Th e mineralization and sorption of the pesticides glyphosate and metribuzin and the pesticide degradation product triazinamin in a fi eld were measured

F. P. Vinther; U. C. Brinch; L. Elsgaard; L. Fredslund; B. V. Iversen; S. Torp; C. S. Jacobsen

2008-01-01

107

Aging of organochlorine pesticides and polychlorinated biphenyls in muck soil: volatilization, bioaccessibility, and degradation.  

PubMed

An organic rich muck soil which is highly contaminated with native organochlorine pesticide (OCs) was spiked with known amounts of (13)C-labeled OCs and nonlabeled polychlorinated biphenyls (PCBs). Spiked soils were aged under indoor, outdoor, and sterile conditions and the change in volatility, surrogate bioaccessibility, and degradation of chemicals was monitored periodically over 730 d. Volatility was measured using a fugacity meter to characterize the soil-air partition coefficient (K(SA) = C(SOIL)/C(AIR)). The fraction of bioaccessible residues was estimated by comparing recoveries of chemical with a mild extractant, hydroxylpropyl-?-cyclodextrin (HPCD) vs a harsh extractant, DCM. K(SA) of the spiked OCs in the nonsterile (Indoor, Outdoor) soils were initially lower and approached the K(SA) of native OCs over time, showing reduction of volatility upon aging. HPCD extractability of spiked OCs and PCBs were negatively correlated with K(SA), which suggests that volatility can be used as a surrogate for bioaccessibility. Degradation of endosulfans, PCB 8 and 28 was observed in the nonsterile soils, and (13)C(6)-?-HCH showed selective degradation of the (+) enantiomer. Enantiomer fractions (EF) in air and HPCD extracts were lower than in nonsterile soils, suggesting greater sequestering of the (+) enantiomer in the soil during microbial degradation. PMID:21204520

Wong, Fiona; Bidleman, Terry F

2011-01-04

108

Pesticides  

Microsoft Academic Search

Organophosphorus (OP) pesticides can be rapidly detected by integrating organophosphorus hydrolase with an optical leaky waveguide biosensor. This enzyme catalyses the hydrolysis of a wide range of organophosphorus compounds causing an increase in the pH. Thus, the direct detection of OP is possible by monitoring of the pH changes associated with the enzyme's activity. This article describes the use of

A C Frazer; A. Simonian; J. Wild; S. Mohr; N. J. Goddarda

1967-01-01

109

75 FR 19388 - Pesticide Product; Registration Application  

Federal Register 2010, 2011, 2012, 2013

...receipt of this application does not imply a decision by the Agency on the application. File Symbol: 524-LOU. Applicant: Monsanto Company, 1300 I St., NW., Suite 450 East, Washington, DC 20005. Product name: MON 87701. Active ingredient:...

2010-04-14

110

Cadmium: Position Document 4. Intent to Cancel Registrations of Pesticide Products Containing Cadmium: Denial of Applications for Registration of Pesticide Products Containing Cadmium; Conclusion of Special Review.  

National Technical Information Service (NTIS)

The Position Document addresses the risks and benefits of pesticide products containing the subject active ingredient. The Agency has determined that the use of products containing the subject active ingredient may meet or exceed a risk criterion describe...

1986-01-01

111

Simultaneous degradation of the pesticides methyl parathion and chlorpyrifos by an isolated bacterial consortium from a contaminated site  

Microsoft Academic Search

The simultaneous degradation of the pesticide methyl parathion and chlorpyrifos was tested using a bacterial consortium obtained by selective enrichment from highly contaminated soils in Moravia (Medellin, Colombia). Microorganisms identified in the consortium were Acinetobacter sp, Pseudomonas putida, Bacillus sp, Pseudomonas aeruginosa, Citrobacter freundii, Stenotrophomonas sp, Flavobacterium sp, Proteus vulgaris, Pseudomonas sp, Acinetobacter sp, Klebsiella sp and Proteus sp. In

Nancy Pino; Gustavo Peñuela

2011-01-01

112

Do farmers understand the information displayed on pesticide product labels? A key question to reduce pesticides exposure and risk of poisoning in the Brazilian Amazon  

Microsoft Academic Search

Brazil is the world's fourth largest consumer of pesticides, and the largest in Latin America. In the Brazilian Amazon, the use of pesticides in varzeas (seasonally flooded land, where fresh vegetables are produced for regional urban markets) is intensive and is perceived by local farmers as necessary for the feasibility of vegetable production in the region. Usage of pesticides in

Andrea Viviana Waichman; Evaldice Eve; Nailson Celso da Silva Nina

2007-01-01

113

US EPA, Pesticide Product Label, ARIZONA INSECTICIDAL ...  

EPA Pesticide Factsheets

... freshening. rli~~ i.,Jst ri{ ~ ~c oIJ:G fer r:..::d for ~: Jajs after t~-,~ last ~eedir'J '. of this product. ... per 100 lb. bod} ,;":l'j',t dJily fer " "'1t1n~~"s '.~':S, ...

2011-04-19

114

Partial degradation of five pesticides and an industrial pollutant by ozonation in a pilot-plant scale reactor.  

PubMed

Aqueous solutions of a mixture of several pesticides (alachlor, atrazine, chlorfenvinphos, diuron and isoproturon), considered PS (priority substances) by the European Commission, and an intermediate product of the pharmaceutical industry (alpha-methylphenylglycine, MPG) chosen as a model industrial pollutant, have been degraded at pilot-plant scale using ozonation. This study is part of a large research project [CADOX Project, A Coupled Advanced Oxidation-Biological Process for Recycling of Industrial Wastewater Containing Persistent Organic Contaminants, Contract No.: EVK1-CT-2002-00122, European Commission, http://www.psa.es/webeng/projects/cadox/index.html] founded by the European Union that inquires into the potential coupling between chemical and biological oxidations for the removal of toxic or non-biodegradable contaminants from water. The evolution of pollutant concentration, TOC mineralization, generation of inorganic species and consumption of O3 have been followed in order to visualize the chemical treatment effectiveness. Although complete mineralization is hard to accomplish, and large amounts of the oxidant are required to lower the organic content of the solutions, the possibility of ozonation cannot be ruled out if partial degradation is the final goal wanted. In this sense, Zahn-Wellens biodegradability tests of the ozonated MPG solutions have been performed, and the possibility of a further coupling with a secondary biological treatment for complete organic removal is envisaged. PMID:16822610

Maldonado, M I; Malato, S; Pérez-Estrada, L A; Gernjak, W; Oller, I; Doménech, Xavier; Peral, José

2006-05-26

115

Farmer perceptions and pesticide use practices in vegetable production in Ghana.  

PubMed

As an initial part of a programme aimed at promoting safe and sound agricultural practices in Ghana, a study was made of farmers' perceptions of pesticides for use and application in vegetable production, using a small survey of 137 farmers who applied pesticides. Field surveys, interviews, questionnaires and analytical games were used to obtain information on the type, scope and extent of use of pesticides, farmers' knowledge of pesticides, and their perceptions about the chemicals' potential for harm. Data from this sample of farmers were used to describe the status of use of pesticides in vegetable cultivation in Ghana. Using chi2 tests, associations between farmers' age and possible pesticide poisoning symptoms, their farm size and method of spraying pesticides, and their perception of pesticide hazard and its perceived effectiveness against pests were also examined. The survey showed that knapsack sprayers were the most widely used type of equipment for spraying pesticides. However, on large-scale vegetable farms of 6-10 acres, motorised sprayers were also used. Various inappropriate practices in the handling and use of pesticides caused possible poisoning symptoms among those farmers who generally did not wear protective clothing. Younger farmers (<45 years of age) were the most vulnerable group, probably because they did more spraying than older farmers (>45 years of age). Farmers did not necessarily associate hazardous pesticides with better pest control. The introduction of well-targeted training programmes for farmers on the need for and safe use of pesticides is advocated. PMID:16532443

Ntow, William J; Gijzen, Huub J; Kelderman, Peter; Drechsel, Pay

2006-04-01

116

Canadian Consumer's Willingness-To-Pay For Pesticide Free Food Products: An Ordered Probit Analysist1  

Microsoft Academic Search

A new crop production system has emerged in western Canada. Pesticide Free ProductionTM (PFPTM) emphasizes reduced pesticide use in conjunction with increased reliance on producer knowledge of agronomic practices that mitigate weed, insect and disease pressure. A contingent valuation survey was undertaken to determine if Canadian consumers would pay a premium for PFPTM food products. Over 65 percent of respondents

J. A. L. Cranfield; Erik Magnusson

117

Toxicity of Fipronil and Its Degradation Products to Procambarus sp.: Field and Laboratory Studies  

Microsoft Academic Search

Fipronil is a phenylpyrazole insecticide that is the active ingredient in the pesticide Icon 6.2 FS™ which is applied to rice\\u000a seeds targeting the rice water weevil. An arthropod-selective insecticide, fipronil blocks the GABA-gated chloride channel\\u000a and is unique in that several of its degradation products have been indicated to be equal or more potent than fipronil. After\\u000a application of

D. Schlenk; D. B. Huggett; J. Allgood; E. Bennett; J. Rimoldi; A. B. Beeler; D. Block; A. W. Holder; R. Hovinga; P. Bedient

2001-01-01

118

Assessing the potential for algae and macrophytes to degrade crop protection products in aquatic ecosystems.  

PubMed

Rates of pesticide degradation in aquatic ecosystems often differ between those observed within laboratory studies and field trials. Under field conditions, a number of additional processes may well have a significant role, yet are excluded from standard laboratory studies, for example, metabolism by aquatic plants, phytoplankton, and periphyton. These constituents of natural aquatic ecosystems have been shown to be capable of metabolizing a range of crop protection products. Here we report the rate of degradation of six crop protection products assessed in parallel in three systems, under reproducible, defined laboratory conditions, designed to compare aquatic sediment systems which exclude macrophytes and algae against those in which macrophytes and/or algae are included. All three systems remained as close as possible to the Organisation for Economic Co-operation and Development (OECD) 308 guidelines, assessing degradation of parent compound in the total system in mass balanced studies using ((14) C) labeled compounds. We observed, in all cases where estimated, significant increases in the rate of degradation in both the algae and macrophyte systems when compared to the standard systems. By assessing total system degradation within closed, mass balanced studies, we have shown that rates of degradation are enhanced in water/sediment systems that include macrophytes and algae. The contribution of these communities should therefore be considered if the aquatic fate of pesticides is to be fully understood. PMID:21298708

Thomas, Kevin A; Hand, Laurence H

2011-01-05

119

MEASURING THE TRANSPORT OF ENDOCRINE DISRUPTING DICARBOXIMIDES AND DEGRADATION PRODUCTS FROM THE SOIL TO THE LOWER TROPOSPHERE  

EPA Science Inventory

A method for measuring the atmospheric flux of a dicarboximide and its degradation products was investigated. A volatile gas laboratory chamber was modified to measure the flux of semi-volatile fungicides. Pesticide application systems and soil incorporation systems were desig...

120

Fate of brominated flame retardants and organochlorine pesticides in urban soil: volatility and degradation.  

PubMed

As the uses of polybrominated diphenyl ethers (BDEs) are being phased out in many countries, soils could become a secondary emission source to the atmosphere. It is also anticipated that the demand for alternative brominated flame retardants (BFRs) will grow, but little is known about their environmental fate in soils. In this study, the volatility and degradation of BFRs and organochlorine pesticides (OCPs) in soil was investigated. A low organic carbon (5.6%) urban soil was spiked with a suite of BFRs and OCPs, followed by incubation under laboratory condition for 360 days. These included BDE- 17, -28, -47, -99; ?- and ?-1,2-dibromo-4-(1,2-dibromoethyl)cyclohexane (TBECH), ?-1,2,5,6-tetrabromocyclooctane (TBCO), and 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE), OCPs: ?-hexachlorocyclohexane (?-HCH) and (13)C(6)-?-HCH, trans-chlordane (TC), and (13)C(10)-TC. The volatility of spiked chemicals was investigated using a fugacity meter to measure the soil-air partition coefficient (K(SA)). K(SA) of some spiked BFRs and OCPs increased from Day 10 to 60 or 90 and leveled off afterward. This suggests that the volatility of BFRs and OCPs decreases over time as the chemicals become more strongly bound to the soil. Degradation of alternative BFRs (?- and ?-TBECH, ?-TBCO, DPTE), BDE-17, and ?-HCH ((13)C-labeled and nonlabeled) was evident in soils over 360 days, but no degradation was observed for the BDE-28, -47, -99, and TC ((13)C-labeled and nonlabeled). A method to separate the enantiomers of ?-TBECH and ?-TBCO was developed and their degradation, along with ?-HCH ((13)C-labeled and nonlabeled) was enantioselective. This is the first study which reports the enantioselective degradation of chiral BFRs in soils. Discrepancies between the enantiomer fraction (EF) of chemicals extracted from the soil by dichloromethane (DCM) and air were found. It is suggested that DCM removes both the sequestered and loosely bound fractions of chemicals in soil, whereas air accesses only the loosely bound fraction, and these two pools are subject to different degrees of enantioselective degradation. This calls for caution when interpreting EFs obtained from DCM extraction of soil with EFs in ambient air. PMID:22243402

Wong, Fiona; Kurt-Karakus, Perihan; Bidleman, Terry F

2012-02-14

121

ORGANOPHOSPHATE PESTICIDE DEGRADATION IN THE PRESENCE OF NATURALLY OCCURRING AQUATIC CONSTITUENTS UNDER DRINKING WATER TREATMENT CONDITIONS  

EPA Science Inventory

Little work to date has solely investigated the kinetics and pathways of pesticide transformations under drinking water treatment conditions. Free chlorine has been found to react with s-triazine, carbamate, and organophosphate pesticides. However, these experimental conditions...

122

Influence of parameters on the heterogeneous photocatalytic degradation of pesticides and phenolic contaminants in wastewater: a short review.  

PubMed

In recent years, the application of heterogeneous photocatalytic water purification processes has gained wide attention due to its effectiveness in degrading and mineralizing the recalcitrant organic compounds as well as the possibility of utilizing the solar UV and visible-light spectrum. This paper aims to review and summarize the recent works on the titanium dioxide (TiO(2)) photocatalytic oxidation of pesticides and phenolic compounds, predominant in storm and wastewater effluents. The effects of various operating parameters on the photocatalytic degradation of pesticides and phenols are discussed. Results reported here suggest that the photocatalytic degradation of organic compounds depends on the type and composition of the photocatalyst and, light intensity, initial substrate concentration, amount of catalyst, pH of the reaction medium, ionic components in water, solvent types, oxidizing agents/electron acceptors, catalyst application mode, and calcination temperature in the water environment. A substantial amount of research has focused on the enhancement of TiO(2) photocatalysis by modification with metal, non-metal and ion doping. Recent developments in TiO(2) photocatalysis for the degradation of various pesticides and phenols are also highlighted in this review. It is evident from the literature survey that photocatalysis has good potential to remove a variety of organic pollutants. However, there is still a need to determine the practical utility of this technique on a commercial scale. PMID:20950926

Ahmed, Saber; Rasul, M G; Brown, R; Hashib, M A

2010-10-14

123

Avoid Counterfeit Pesticide Products for Dogs and Cats  

MedlinePLUS

... menu Learn the Issues Air Chemicals and Toxics Climate Change Emergencies Green Living Health and Safety Land and Cleanup Pesticides Waste Water Science & Technology Air Climate Change Ecosystems Health Land, Waste and Cleanup Pesticides Substances ...

124

Pesticide consumption and productivity and the potential of IPM in Bangladesh.  

PubMed

The paper analyses trends in consumption, productivity and the determinants of pesticide use in Bangladesh over a 33 year period (1977-2009), including a discussion on the scope to expand Integrated Pest Management (IPM) practices. Pesticide use grew at an alarming rate of 10.0% per year (p<0.01) although the corresponding response in yield growth of major crops has been minimal (<1.0% per year). Pesticide productivity (i.e., 'gross value added from crops at constant prices' per 'kg of active ingredients of all pesticides used') is declining steadily at a rate of -8.6% per year (p<0.01). Adoption of Green Revolution (GR) technology, crop diversification, average farm size and literacy rate are the most significant determinants of pesticide use, whereas research and development (R&D) investment depresses pesticide use. Consistent evidence of excessive pesticide use in Bangladesh was observed. Although the government has shifted focus from pesticide use to IPM, its coverage remains inadequate as only 7.4% of the total farmers are covered after 30 years of effort. Tighter pesticide regulation and its effective implementation, and expansion of IPM through public, private and non-governmental organisation (NGO) stakeholders are suggested to reduce pesticide consumption. PMID:23314122

Rahman, Sanzidur

2013-01-09

125

Pesticide and transformation product detections and age-dating relations from till and sand deposits  

USGS Publications Warehouse

Pesticide and transformation product concentrations and frequencies in ground water from areas of similar crop and pesticide applications may vary substantially with differing lithologies. Pesticide analysis data for atrazine, metolachlor, alachlor, acetochlor, and cyanazine and their pesticide transformation products were collected at 69 monitoring wells in Illinois and northern Indiana to document occurrence of pesticides and their transformation products in two agricultural areas of differing lithologies, till, and sand. The till is primarily tile drained and has preferential fractured flow, whereas the sand primarily has surface water drainage and primary porosity flow. Transformation products represent most of the agricultural pesticides in ground water regardless of aquifer material - till or sand. Transformation products were detected more frequently than parent pesticides in both the till and sand, with metolachlor ethane sulfonic acid being most frequently detected. Estimated ground-water recharge dates for the sand were based on chlorofluorocarbon analyses. These age-dating data indicate that ground water recharged prior to 1990 is more likely to have a detection of a pesticide or pesticide transformation product. Detections were twice as frequent in ground water recharged prior to 1990 (82%) than in ground water recharged on or after 1990 (33%). The highest concentrations of atrazine, alachlor, metolachlor, and their transformation products, also were detected in samples from ground water recharged prior to 1990. These age/pesticide detection relations are opposite of what would normally be expected, and may be the result of preferential flow and/or ground-water mixing between aquifers and aquitards as evident by the detection of acetochlor transformation products in samples with estimated ground-water ages predating initial pesticide application. ?? 2007 American Water Resources Association.

Warner, K. L.; Morrow, W. S.

2007-01-01

126

Forced degradation study of thiocolchicoside: characterization of its degradation products.  

PubMed

Thiocolchicoside (TCC, N-[1,2-dimethoxy-10-methylsulphanyl-9-oxo-3-(3,4,5-trihydroxy-6-hydroxymethyl-tetrahydropyran-2-yloxy)-5,6,7,9-tetrahydro-benzo[a]heptalen-7-yl]-acetamide) was subjected to hydrolytic, oxidative, and photolytic stresses. TCC underwent degradation in acidic, basic, and oxidative conditions, while it was stable toward other stress conditions. The degradation products (DPs) were detected and their separation was achieved on a SGE Wakosil C18RS 5?m (250*4.6 mm; SGE) column employing a gradient LC-MS method for a total time of analysis of 18 min. The mass fragmentation pathways of both thiocolchicoside and its degradation products were established using LC-MS experiments assigning the structures to the DPs. In particular, five DPs were identified as: D1SO (N-[1,2-dimethoxy-10-methylsulphoxide-9-oxo-3-(3,4,5-trihydroxy-6-hydroxymethyl-tetrahydropyran-2-yloxy)-5,6,7,9-tetrahydro-benzo[a]heptalen-7-yl]-acetamide), D1SO(2) (N-[1,2-dimethoxy-10-methylsulphone-9-oxo-3-(3,4,5-trihydroxy-6-hydroxymethyl-tetrahydropyran-2-yloxy)-5,6,7,9-tetrahydro-benzo[a]heptalen-7-yl]-acetamide), D2 ([1,2-dimethoxy-10-methylsulphanyl-9-oxo-3-(3,4,5-trihydroxy-6-hydroxymethyl-tetrahydropyran-2-yloxy)-5,6,7,9-tetrahydro-benzo[a]heptalen-7-yl]-amine), D3 (N-[1,2-dimethoxy-3-hydroxy-10-methylsulphanyl-9-oxo-5,6,7,9-tetrahydro-benzo[a]heptalen-7-yl]-acetamide or 3-O-demethylthiocolchicine), D4 ([1,2-dimethoxy-3-hydroxy-10-methylsulphanyl-9-oxo-5,6,7,9-tetrahydro-benzo[a]heptalen-7-yl]-amine or N-deacetyl-3-O-demethylthiocochicine). Moreover, the structures of DPs were confirmed by synthesis of the reference standards which were fully characterized by MS, NMR, IR analyses. Finally a comprehensive degradation scheme of TCC was proposed allowing to outline D1SO and D3 as the indicators of its stability for oxidative and hydrolytic stress conditions. PMID:22226415

Erika, Del Grosso; Silvio, Aprile; Giorgio, Grosa

2011-12-17

127

The mobility and degradation of pesticides in soils and the pollution of groundwater resources  

Microsoft Academic Search

Pesticides, the most cost-effective means of pest and weed control, allow the maintenance of current yields and so contribute to economic viability. Concern about the environmental impact of repeated pesticide use has prompted research into the environmental fate of these agents, which can emigrate from treated fields to air, other land and waterbodies. How long the pesticide remains in the

Manuel Arias-Estévez; Eugenio López-Periago; Elena Martínez-Carballo; Jesús Simal-Gándara; Juan-Carlos Mejuto; Luis García-Río

2008-01-01

128

Bioremediation of single and mixture of pesticide-contaminated soils by mixed pesticide-enriched cultures.  

PubMed

In the present study, degradation efficiencies for individual as well as mixed pesticide in different Indian soils, by mixed pesticide-enriched cultures, were evaluated under submerged and unsaturated conditions, Lindane (L), methyl parathion (MP), carbofuran (C), and a mixture of L, MP, and C were used in the study. For all the various conditions considered, methyl parathion degradation was the maximum and lindane degradation was the minimum. The degradation kinetics of the pesticides in sandy, clayey, compost, and red soils by various microbial isolates were studied. It was observed that adsorption was maximum and degradation of pesticides was minimum in compost soil. The degradation efficiencies of pesticides in liquid phase associated with soil sediment were less than those under the normal liquid phase conditions as leaching of pesticides from soil phase was continuous. Pesticide degradation was more in submerged soils compared to that in unsaturated soils. The degradation by-products of individual and mixed pesticides in liquid, unsaturated, and submerged soils were identified. Different metabolites were produced under submerged and unsaturated conditions. PMID:21424248

Rama Krishna, K; Philip, Ligy

2011-03-19

129

Characterization of a strain of Pseudomonas putida isolated from agricultural soil that degrades cadusafos (an organophosphorus pesticide).  

PubMed

Bacteria capable of degrading the pesticide, cadusafos, were isolated from agricultural soil using an enrichment method. In this way, five distinct cadusafos-degrading strains of Pseudomonas putidia were isolated, and were characterized using morphological and biochemical analysis, as well as 16S rRNA sequencing. Strain PC1 exhibited the greatest cadusafos degradation rate and was consequently selected for further investigation. Degradation of cadusafos by strain PC1 was rapid at 20 and 37°C, but was greatly reduced (~1.5-fold) by the presence of carbon sources. Strain PC1 was able to effectively degrade cadusafos in sterilized soil using low inoculum levels. The maximum degradation rate of cadusafos (V ( max )) was calculated as 1.1 mg l(-1 )day(-1), and its saturation constant (K ( s )) was determined as 2.5 mg l(-1). Bacteria such as strain PC1, that use cadusafos as a carbon source, could be employed for the bioremediation of sites contaminated with pesticides. PMID:22805799

Abo-Amer, Aly E

2011-08-28

130

Productivity, pesticides, and management of the Peregrine Falcon in Arizona  

USGS Publications Warehouse

In the decade since research commenced with the Peregrine in Arizona, over 60 sites have been identified which historically or presently are occupied by breeding pairs. Productivity was determined for about 120 breeding attempts from 1975-85. Almost all sites, for which productivity information is available for two or more years, have hatched young. Average values for fledging success were ca. 1.4 young/attempt for all active sites and ca. 2.3 young/attempt for successful sites. Eggshell thickness values were highly varied, but few samples reflect thinning sufficient to cause reproductive failure, and the population appears to be increasing slightly. Management practices which can further benefit the falcon include: controlling pesticide use, habitat protection, and information management.

Ellis, D.H.

1985-01-01

131

Influence of parameters on the heterogeneous photocatalytic degradation of pesticides and phenolic contaminants in wastewater: A short review  

Microsoft Academic Search

In recent years, the application of heterogeneous photocatalytic water purification processes has gained wide attention due to its effectiveness in degrading and mineralizing the recalcitrant organic compounds as well as the possibility of utilizing the solar UV and visible-light spectrum. This paper aims to review and summarize the recent works on the titanium dioxide (TiO2) photocatalytic oxidation of pesticides and

Saber Ahmed; M. G. Rasul; R. Brown; M. A. Hashib

2011-01-01

132

40 CFR 152.10 - Products that are not pesticides because they are not intended for a pesticidal purpose.  

Code of Federal Regulations, 2013 CFR

...that is not intended to prevent, destroy, repel, or mitigate a pest, or to defoliate, desiccate or regulate the growth of plants, is not considered to be a pesticide. The following types of products or articles are not considered to be...

2013-07-01

133

40 CFR 152.10 - Products that are not pesticides because they are not intended for a pesticidal purpose.  

Code of Federal Regulations, 2012 CFR

...that is not intended to prevent, destroy, repel, or mitigate a pest, or to defoliate, desiccate or regulate the growth of plants, is not considered to be a pesticide. The following types of products or articles are not considered to be...

2012-07-01

134

40 CFR 152.10 - Products that are not pesticides because they are not intended for a pesticidal purpose.  

Code of Federal Regulations, 2011 CFR

...that is not intended to prevent, destroy, repel, or mitigate a pest, or to defoliate, desiccate or regulate the growth of plants, is not considered to be a pesticide. The following types of products or articles are not considered to be...

2011-07-01

135

[Residual levels of pesticides in freshwater fish from Beijing aquatic product markets and health risk assessment].  

PubMed

Health risks by fish consumption were assessed following the investigation of the residual levels of 25 pesticides in four kinds of freshwater fish from 4 aquatic product markets in Beijing using ultrasonic extraction-GC-MS. Eighteen pesticides were detected from the 48 samples collected. Acetochlor (97.9%) and beta-HCH (93.8%) showed high detection rates. The pesticide detected in highest concentration was chlorothalonil (1 779.4 microg x kg(-1)), followed by deltamethrin (620.3 microg x kg(-1)). Coexistence of 2-10 kinds of pesticides in fish was found with the total pesticide concentration in range of 2.7-1932 microg x kg(-1). Based on the averaged fish consumption of Beijing residents, the health risk of the studied pesticides by freshwater fish consumption was calculated as 0.043 43, suggesting a relatively low health risk. PMID:23487947

Yu, Zhi-Yong; Jin, Fen; Sun, Jing-Fang; Yuan, Sheng-Guang; Zheng, Bei; Zhang, Wen-Jing; An, Wei; Yang, Minm

2013-01-01

136

Toxicity of pesticides to fish. Volume 2  

SciTech Connect

This book is the first major attempt to review comprehensively all available information on the environmental fate of pesticides and their acute and chronic effects to fish. Topics considered include toxicity of individual compounds, safe concentrations, and toxicity to different age groups; influence of environmental conditions on the toxicity of pesticides to fish; toxicity of formulations, isomers, and degradation products; joint action of pesticide mixture. Insecticide resistance in fish; poly-chlorinated biphenyls and related compounds; and environmental hazard evaluation and prediction.

Murty, A.S.

1986-01-01

137

Inoculation with a mixed degrading culture improves the pesticide removal of an on-farm biopurification system.  

PubMed

To investigate whether the pesticide removal in on-farm biopurification systems (BPS) filled with two different types of substrata (biomix and plastic carriers) is affected by inoculation with a pesticide-degrading strain or mixed culture, lab-scale BPS used to treat chloropropham point source contaminations were bioaugmented with either a specialized chloropropham-degrading strain or a chloropropham-degrading enrichment culture. Application of both inoculum types leads to an accelerated degradation activity in the columns filled with plastic carriers. For both substratum types, inoculation with the mixed culture resulted in a lower breakthrough of the toxic intermediate 3-chloroaniline at high hydraulic loads, compared to inoculation with the pure isolate and no inoculation. This study suggests that the use of plastic carrier materials could be a proficient alternative to the use of a conventional biomix as a substratum in on-farm BPS and that inoculation with a mixed degrading culture can reduce the leaching of more mobile toxic intermediates. PMID:23708426

Verhagen, Pieter; De Gelder, Leen; Boon, Nico

2013-05-26

138

Current Status of Plant Products as Botanical Pesticides in storage pest management  

Microsoft Academic Search

The increasing concern over the level of pesticide residues in food has encouraged researchers to look for alternatives of synthetic pesticides. Their indiscriminate use has led to the development of resistant strains of pests as well as different environmental and human health problems. Recently, in different parts of the world, attention has been paid towards exploitation of higher plant products

N. K. Dubey; Bhawana Srivastava; Ashok Kumar

2008-01-01

139

Soil pesticide residue degradation and soil sample management procedures for environmental forensics  

Microsoft Academic Search

The overall goal of this project was to examine soil sampling procedures of each state regulatory agency that regulates pesticide use in that state, and to offer a standardized soil sampling protocol. ^ A survey of each SLA was conducted to determine the types of containers that are typically used when collecting soil samples for pesticide residue analysis and, on

George N. Saxton

2004-01-01

140

Photostability and photodegradation pathways of distinctive pesticides.  

PubMed

Transformation of pesticides in the environment is a highly complex process affected by different factors. Biological and physical-chemical factors may play a role in the degradation to variable extent. Photodecomposition might be regarded as one of the most crucial factors affecting the fate of pesticides. Therefore, our study focused on revealing specific details of the photolytic degradation of pesticides. The toxicity of the examined pesticides is well known; however, little information is available regarding their natural degradation processes. More detailed examinations are required to reveal the exact mechanism of the pesticide decomposition and the biological impacts of the degradates. Significance of this study is enhanced by the fact that decomposition of pesticides may result in the formation of toxic degradation products. The photolytic degradation of frequently applied pesticides (e.g., acetochlor, simazine, chlorpyrifos, and carbendazim) with different chemical structures was investigated. An immersible ultraviolet light source was applied to induce photodegradation. The degradation processes were followed by thin-layer chromatography and gas chromatography/mass spectrometry techniques. Electron ionization mass spectrometry was used to identify the degradation species. Detailed mechanisms of photolytic transformation were established by identification of each degradate. The photolytic degradation of pesticides of distinctive chemical character exhibited markedly different photodecomposition mechanisms. At least four degradation species were detected and identified in each case. Loss of alkyl, chloro, and hydroxyl groups as well as cleavage of alkyloxy, amide, amino-alkyl, and ester bonds might be regarded as typical decomposition patterns. Deamination and ring opening might be observed at the last stages of decomposition. PMID:19141805

Kiss, Attila; Virág, Diána

2009-01-13

141

40 CFR 158.2171 - Experimental use permit microbial pesticides product analysis data requirements table.  

Code of Federal Regulations, 2013 CFR

...Pesticides Product Analysis Data Requirements Test guideline No. Data requirement All use...1250 Deposition of a sample in a nationally recognized...analytical method and data would suffice to support...generally an analysis of samples is a compilation...

2013-07-01

142

40 CFR 158.2120 - Microbial pesticides product analysis data requirements table.  

Code of Federal Regulations, 2013 CFR

...Pesticides Product Analysis Data Requirements Test guideline No. Data requirement All usepatterns...1250 Deposition of a sample in a nationally recognized...notes are applicable to the data requirements for...agreement to ensure that the sample will be...

2013-07-01

143

Guidance for the Reregistration of Pesticide Products Containing Streptomycin and Streptomycin Sulfate as the Active Ingredient.  

National Technical Information Service (NTIS)

The document contains information regarding the registration of pesticide products containing the subject active ingredient, viz.: streptomycin and streptomycin sulfate. The document describes how to register under a registration standard, the regulatory ...

1988-01-01

144

Guidance for the Reregistration of Pesticide Products Containing Ethion as the Active Ingredient.  

National Technical Information Service (NTIS)

The document contains information regarding the reregistration of pesticide products containing the subject active ingredient. The document includes how to register under a registration standard, regulatory position and rationale, and summaries of data re...

1982-01-01

145

Guidance for the Reregistration of Pesticide Products Containing Ethion as the Active Ingredient.  

National Technical Information Service (NTIS)

The document contains information regarding the registration of pesticide products containing the subject active ingredient. The document includes how to register under a registration standard, regulatory position and rationale, and summaries of date requ...

1989-01-01

146

40 CFR 152.8 - Products that are not pesticides because they are not for use against pests.  

Code of Federal Regulations, 2010 CFR

40 Ç Protection of Environment Ç 25 Ç 2012-07-01 Ç 2012-07-01 Ç false Ç Products that are not pesticides because they are not for use against pests. Ç 152.8 Ç Section 152.8 Ç Protection of Environment Ç ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) Ç PESTICIDE PROGRAMS Ç PESTICIDE REGISTRATION...

2012-07-01

147

Analysis of polar pesticides in rainwater in Denmark by liquid chromatography–tandem mass spectrometry  

Microsoft Academic Search

A new LC–MS–MS method for analysis of rainwater has been developed and validated for 53 pesticides, degradation products of pesticides and selected nitrophenols. The method was used to monitor the concentration of pesticides in rainwater at one location near Roskilde, Denmark from February 2000 to August 2000. Sampling was done in periods of up to 4 weeks using a cooled

R Bossi; K. V Vejrup; B. B Mogensen; W. A. H Asman

2002-01-01

148

Low environmentally relevant levels of bioactive xenobiotics and associated degradation products cause cryptic perturbations of metabolism and molecular stress responses in Arabidopsis thaliana.  

PubMed

Anthropic changes and chemical pollution confront wild plant communities with xenobiotic combinations of bioactive molecules, degradation products, and adjuvants that constitute chemical challenges potentially affecting plant growth and fitness. Such complex challenges involving residual contamination and mixtures of pollutants are difficult to assess. The model plant Arabidopsis thaliana was confronted by combinations consisting of the herbicide glyphosate, the fungicide tebuconazole, the glyphosate degradation product aminomethylphosphonic acid (AMPA), and the atrazine degradation product hydroxyatrazine, which had been detected and quantified in soils of field margins in an agriculturally intensive region. Integrative analysis of physiological, metabolic, and gene expression responses was carried out in dose-response experiments and in comparative experiments of varying pesticide combinations. Field margin contamination levels had significant effects on plant growth and metabolism despite low levels of individual components and the presence of pesticide degradation products. Biochemical and molecular analysis demonstrated that these less toxic degradation products, AMPA and hydroxyatrazine, by themselves elicited significant plant responses, thus indicating underlying mechanisms of perception and transduction into metabolic and gene expression changes. These mechanisms may explain observed interactions, whether positive or negative, between the effects of pesticide products (AMPA and hydroxyatrazine) and the effects of bioactive xenobiotics (glyphosate and tebuconazole). Finally, the metabolic and molecular perturbations induced by low levels of xenobiotics and associated degradation products were shown to affect processes (carbon balance, hormone balance, antioxidant defence, and detoxification) that are likely to determine environmental stress sensitivity. PMID:23645866

Serra, Anne-Antonella; Nuttens, Andréïna; Larvor, Vanessa; Renault, David; Couée, Ivan; Sulmon, Cécile; Gouesbet, Gwenola

2013-05-03

149

Spatial variation in the degradation rate of the pesticides isoproturon, azoxystrobin and diflufenican in soil and its relationship with chemical and microbial properties  

Microsoft Academic Search

The extent of within field variability in the degradation rate of the pesticides isoproturon, azoxystrobin and diflufenican, and the role of intrinsic soil factors and technical errors in contributing to the variability, was investigated in sites on sandy-loam and clay-loam. At each site, 40 topsoil samples were taken from a 160×60m area, and pesticides applied in the laboratory. Time to

Gary D. Bending; Suzanne D. Lincoln; Rodney N. Edmondson

2006-01-01

150

SORPTION, DEGRADATION, AND MINERALIZATION OF CARBARYL IN SOILS, FOR SINGLE-PESTICIDE AND MULTIPLE-PESTICIDE SYSTEMS  

EPA Science Inventory

Sorption, degradation, and mineralization of carbaryl (1-naphthyl N-methylcarbamate) alone and in mixtures with atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine) and diuron (N1-(3,4-dichlorophenyl)-N, N-dimethylurea) were characterized for two topsoils and their re...

151

76 FR 16417 - Product Cancellation Order for Certain Pesticide Registrations  

Federal Register 2010, 2011, 2012, 2013

...interested in the sale, distribution, or use of pesticides...Agri Packaging & Logistics, Inc., 2509 South Frontage...is March 23, 2011. Any distribution, sale, or use of existing...provided that such sale, distribution, or use is consistent...

2011-03-23

152

Contamination by Persistent Chemical Pesticides in Livestock Production Systems  

Microsoft Academic Search

The impact of persistent organic pesticides represents one of the major environmental problems as reported in several studies\\u000a and reflected in some mandatory actions at the inter-governmental level. In particular, isomers of Hexachlorocyclohexane (HCH),\\u000a like many others Organochlorine Pesticides (OCPs), are of human health and environmental concern due to their persistence\\u000a in the biosphere. In industrialised countries, Lindane (the ?-isomer

Bruno Ronchi; Pier Paolo Danieli

153

Assessment of bioavailability of pesticides in soils and identification of pesticide degradation drivers using the in-situ Mass Distribution Quotient (iMDQ)  

NASA Astrophysics Data System (ADS)

The in-situ Mass Distribution Quotient (iMDQ) has recently been shown to reliably describe the bioavailability and mineralization of the widely applied pesticide isoproturon in agricultural soils. It is determined by pore water extraction from previously incubated soil samples and subsequent assessment of the mass distribution between solid and liquid phase. The method was verified by comparing the bioavailability with co-metabolic mineralization in soils under optimum microbial soil conditions (water tension -15 kPa and bulk density 1.3 g cm-3). A comparison of the results with the chemical partitioning assessed by the Kd method has shown a higher accuracy of the new method. By combining the iMDQ/pore water extraction method with mineralization of the pesticide under optimum microbial conditions in the soils, further information about mineralization and degradation processes could be obtained or confirmed: a) Metabolically outstanding soils could be identified due to inconsistency between bioavailability and mineralization when compared to the co-metabolic soils. In a metabolically hampered soil, the mineralization was very low compared to the bioavailability and in a soil with metabolically IPU degrading microorganisms the mineralization was extremely high despite low bioavailability. b) Analysis of metabolite patterns in soil water fractions of a degradation experiment allowed for an additional identification of the metabolic status of the soil. In co-metabolic soils, the diversity of metabolites increased proportionally with the degree of mineralization of the parent compound, whereas in a metabolically hampered soil the metabolite pattern was very diverse despite low mineralization. c) A quite stable fractioning between total mineralization of the parent compound to CO2 and build-up of non-extractable bound residues was found. This is a hint that also during co-metabolic degradation that can up to now not be attributed to a certain group of microorganisms, very similar processes take place in different soils. d) It could be shown that soil parameters governing the bioavailability of the compound differ between soils. Although TOC and pH could again be identified as the most important factors for the sorption strength of soils towards isoproturon, the bioavailability itself was driven by a combination of water content and sorption strength that was unique for each soil sample. f) The partitioning of parent compound and primary metabolites remained quite stable during the degradation and mineralization. Further investigations focusing on the microbial side of co-metabolic degradation are in progress. In the future, the method could be used to investigate more compounds, the effectiveness of methods to increase bioavailability in-situ without the need for degradation experiments, and the identification and analysis of degradation pathways in-situ. Other processes that are important for risk assessment, like leaching, have already been investigated with similar methods.

Folberth, Christian

2010-05-01

154

[Effects of pesticides on cytokines production by human peripheral blood mononuclear cells--fenitrothion and glyphosate].  

PubMed

In patients with pesticides poisoning, human immune system seems to be damaged. However, the effects of pesticides on human immune system, especially on cytokines production, have not been understood well. We investigated the effects of fenitrothion (MEP), an organophosphorus insecticide, and glyphosate (GLP), a phosphorus containing amino acid-type herbicide, on cytokines production by human peripheral blood mononuclear cells (PBMC). MEP inhibited the proliferative activity of PBMC at ranging from 1 to 500 microM in a concentration-dependent manner, whereas GLP had a slight inhibitory effect even at 1000 microM. The production of IFN-gamma and IL-2 was inhibited by MEP in a concentration-dependent manner, but GLP slightly inhibited their production only at 1000 microM. The production of TNF-alpha and IL-1 beta was not affected by MEP and GLP at the concentrations which significantly inhibited the proliferative activity and T cell-derived cytokine production. MEP inhibited the production of T cell-derived cytokine (IFN-gamma and IL-2), which indicates that MEP might have the potential of immunosuppressive action. On the other hand, GLP might be a pesticide with only a little damage to the immune system, according to the results in cytokines production. These results suggest that pesticides inhibit the immune system differently, and the grasp of immune condition might be useful for the prognostic presumption and the infectious danger of degree in patients with pesticides poisoning. PMID:12108020

Nakashima, Keiji; Yoshimura, Tomoaki; Mori, Hiromi; Kawaguchi, Mayumi; Adachi, Shino; Nakao, Toshiya; Yamazaki, Futoshi

2002-04-01

155

A dual-template imprinted capsule with remarkably enhanced catalytic activity for pesticide degradation and elimination simultaneously.  

PubMed

A new strategy of reactant-product-dual-template imprinting incorporated with hollow morphology to improve the catalysis efficiency of microspheres was developed. The synthesized capsule can achieve degradation of the reactant and elimination of its product simultaneously. PMID:23264959

Guo, Yong; Guo, Tianying

2013-02-01

156

EXPOSURE OF PRESCHOOL CHILDREN TO CHLORPYRIFOS AND ITS DEGRADATION PRODUCT 3,5,6-TRICHLORO-2-PYRIDINOL IN THEIR EVERYDAY ENVIRONMENTS  

EPA Science Inventory

As part of the Children's Total Exposure to Persistent Pesticides and Other Persistent Organic Pollutants (CTEPP) study, we investigated the exposures of preschool children to chlorpyrifos and its degradation product 3,5,6-trichloro-2-pyridinol (TCP) in their everyday environment...

157

Target product profile choices for intra-domiciliary malaria vector control pesticide products: repel or kill?  

PubMed Central

Background The most common pesticide products for controlling malaria-transmitting mosquitoes combine two distinct modes of action: 1) conventional insecticidal activity which kills mosquitoes exposed to the pesticide and 2) deterrence of mosquitoes away from protected humans. While deterrence enhances personal or household protection of long-lasting insecticidal nets and indoor residual sprays, it may also attenuate or even reverse communal protection if it diverts mosquitoes to non-users rather than killing them outright. Methods A process-explicit model of malaria transmission is described which captures the sequential interaction between deterrent and toxic actions of vector control pesticides and accounts for the distinctive impacts of toxic activities which kill mosquitoes before or after they have fed upon the occupant of a covered house or sleeping space. Results Increasing deterrency increases personal protection but consistently reduces communal protection because deterrent sub-lethal exposure inevitably reduces the proportion subsequently exposed to higher lethal doses. If the high coverage targets of the World Health Organization are achieved, purely toxic products with no deterrence are predicted to generally provide superior protection to non-users and even users, especially where vectors feed exclusively on humans and a substantial amount of transmission occurs outdoors. Remarkably, this is even the case if that product confers no personal protection and only kills mosquitoes after they have fed. Conclusions Products with purely mosquito-toxic profiles may, therefore, be preferable for programmes with universal coverage targets, rather than those with equivalent toxicity but which also have higher deterrence. However, if purely mosquito-toxic products confer little personal protection because they do not deter mosquitoes and only kill them after they have fed, then they will require aggressive "catch up" campaigns, with behaviour change communication strategies that emphasize the communal nature of protection, to achieve high coverage rapidly.

2011-01-01

158

[Induce of laccase from Trametes gallica and its degradation on neutral dyes and organophosphorus pesticides].  

PubMed

The characteristics of the induction of laccase in Trametes gallica under different initial cultural pH, incubation time by different inducers were discussed, as well as the effects of temperature, pH and time on laccase degradation of six dyes and four organophosphors. The results showed that RB-bright blue, ABTS and o-toluidine affected the production of laccase at different levels, and ABTS was the best inductive agent in our test conditions, whose optimal initial pH and incubation time were 4.0 and 13 days, respectively. The appropriate reaction temperature of the laccase produced was 38 degrees C, and it got a good stability, for it could retain 78.6% of the enzyme activity after 20 min holding at 40 degrees C. Mediated by ABTS, the optimal temperature for laccase to degrade the six types of neutral dyes could be divided into two cases, that was 30 degrees C (neutral black, neutral bordeaux, neutral pink, methyl orange) and 60 degrees C (neutral dark yellow, cresol red), the optimal pH were 6.0 (neutral black), 2.0 (neutral bordeaux, neutral pink) and 4.0 (methyl orange, neutral dark yellow, cresol red), respectively, while the optimal times separately were 6 h (methyl orange, neutral dark yellow, cresol red), 12 h (neutral pink) and 24 h (neutral bordeaux). And using the same inductive agent, the best temperature for laccase to degrade dimethoate, chlorpyrifos, trichlorfon and parathion-pyridazine was 25 degrees C, the suitable time was 9 h, and the optimal pH was 10.0 for dimethoate, chlorpyrifos and parathion-pyridazine, and 8.0 for trichlorfon. PMID:22384601

Jing, De-Jun; Huang, Jian-Bo; Yang, Zhou-Ping; Hu, Rong; Cheng, Zi-Zhang; Huang, Qian-Ming

2011-12-01

159

DESIGNING PESTICIDE METABOLIC PATHWAY/DEGRADATE DATABASES FOR REGISTRANT SUBMITTED HEALTH EFFECTS/ECOLOGICAL EFFECTS DATA  

EPA Science Inventory

OPPTS requires information on the toxic effects of pesticide metabolites as well as the parent chemical. Currently, OPP receives metabolic maps with registrant study data submissions, but there is no efficient way to access previously submitted maps on similar chemicals to help w...

160

Photo-degradation products of pramipexole.  

PubMed

Two pyrrolidine compounds (1 and 2) were isolated from photo-degradation of Bi-Sifrol tablets. Compound 1 was esterified to p-bromophenacyl ester as single-crystal, and then the structure was elucidated by single-crystal X-ray study. Compound 2 was determined by 2D NMR and mass spectra. Otherwise, we established that the photo-degradation of pramipexole was smoothly carried out in the methanol solution, and elucidate the degradation mechanism. PMID:22425455

Nishimura, Eiji; Kugimiya, Aya; Naoki, Hideo; Hamanaka, Nobuyuki

2012-03-01

161

Biodegradation and bioremediation potential of diazinon-degrading Serratia marcescens to remove other organophosphorus pesticides from soils.  

PubMed

The ability of diazinon-degrading Serratia marcescens to remove organophosphorus pesticides (OPPs), i.e. chlorpyrifos (CP), fenitrothion (FT), and parathion (PT) was studied in a mineral salt medium (MSM) and in three soils of different characteristics. This strain was capable of using all insecticides at concentration of 50 mg/l as the only carbon source when grown in MSM, and 58.9%, 70.5%, and 82.5% of the initial dosage of CP, FT, and PT, respectively was degraded within 14 days. The biodegradation experiment showed that autochthonous microflora in all soils was characterized by a degradation potential of all tested OPPs; however, the initial lag phases for degradation of CP and FT, especially in sandy soil, were observed. During the 42-day experiment, 45.3%, 61.4% and 72.5% of the initial dose of CP, FT, and PT, respectively, was removed in sandy soil whereas the degradation of CP, FT, and PT in the same period, in sandy loam and silty soils reached 61.4%, 79.7% and 64.2%, and 68.9%, 81.0% and 63.6%, respectively. S. marcescens introduced into sterile soils showed a higher degradation potential (5-13%) for OPPs removal than those observed in non-sterile soil with naturally occurring attenuation. Inoculation of non-sterile soils with S. marcescens enhanced the disappearance rates of all insecticides, and DT50 for CP, FT, and PT was reduced by 20.7, 11.3 and 13.0 days, and 11.9, 7.0 and 8.1 days, and 9.7, 14.5 and 12.6 days in sandy, sandy loam, and silty soils, respectively, in comparison with non-sterile soils with only indigenous microflora. This ability of S. marcescens makes it a suitable strain for bioremediation of soils contaminated with OPPs. PMID:23333465

Cyco?, Mariusz; ?mijowska, Agnieszka; Wójcik, Marcin; Piotrowska-Seget, Zofia

2013-01-17

162

Infusion fluids contain harmful glucose degradation products  

PubMed Central

Purpose Glucose degradation products (GDPs) are precursors of advanced glycation end products (AGEs) that cause cellular damage and inflammation. We examined the content of GDPs in commercially available glucose-containing infusion fluids and investigated whether GDPs are found in patients’ blood. Methods The content of GDPs was examined in infusion fluids by high-performance liquid chromatography (HPLC) analysis. To investigate whether GDPs also are found in patients, we included 11 patients who received glucose fluids (standard group) during and after their surgery and 11 control patients receiving buffered saline (control group). Blood samples were analyzed for GDP content and carboxymethyllysine (CML), as a measure of AGE formation. The influence of heat-sterilized fluids on cell viability and cell function upon infection was investigated. Results All investigated fluids contained high concentrations of GDPs, such as 3-deoxyglucosone (3-DG). Serum concentration of 3-DG increased rapidly by a factor of eight in patients receiving standard therapy. Serum CML levels increased significantly and showed linear correlation with the amount of infused 3-DG. There was no increase in serum 3-DG or CML concentrations in the control group. The concentration of GDPs in most of the tested fluids damaged neutrophils, reducing their cytokine secretion, and inhibited microbial killing. Conclusions These findings indicate that normal standard fluid therapy involves unwanted infusion of GDPs. Reduction of the content of GDPs in commonly used infusion fluids may improve cell function, and possibly also organ function, in intensive-care patients. Electronic supplementary material The online version of this article (doi:10.1007/s00134-010-1873-x) contains supplementary material, which is available to authorized users.

Bryland, Anna; Broman, Marcus; Erixon, Martin; Klarin, Bengt; Linden, Torbjorn; Friberg, Hans; Wieslander, Anders; Kjellstrand, Per; Ronco, Claudio; Carlsson, Ola

2010-01-01

163

Exposure assessment for pesticide intake from multiple food products: a Bayesian latent-variable approach.  

PubMed

Pesticide risk assessment for food products involves combining information from consumption and concentration data sets to estimate a distribution for the pesticide intake in a human population. Using this distribution one can obtain probabilities of individuals exceeding specified levels of pesticide intake. In this article, we present a probabilistic, Bayesian approach to modeling the daily consumptions of the pesticide Iprodione though multiple food products. Modeling data on food consumption and pesticide concentration poses a variety of problems, such as the large proportions of consumptions and concentrations that are recorded as zero, and correlation between the consumptions of different foods. We consider daily food consumption data from the Netherlands National Food Consumption Survey and concentration data collected by the Netherlands Ministry of Agriculture. We develop a multivariate latent-Gaussian model for the consumption data that allows for correlated intakes between products. For the concentration data, we propose a univariate latent-t model. We then combine predicted consumptions and concentrations from these models to obtain a distribution for individual daily Iprodione exposure. The latent-variable models allow for both skewness and large numbers of zeros in the consumption and concentration data. The use of a probabilistic approach is intended to yield more robust estimates of high percentiles of the exposure distribution than an empirical approach. Bayesian inference is used to facilitate the treatment of data with a complex structure. PMID:18808397

Chatterjee, Ayona; Horgan, Graham; Theobald, Chris

2008-09-19

164

Diazinon - Position Document 4. Intent to Cancel Registrations of Denial of Applications for Registration of Pesticide Products Containing Diazinon; Conclusion of Special Review.  

National Technical Information Service (NTIS)

Diazinon is frequently used as a pesticide on golf courses and sod farms. The Position Document addresses the risks and benefits of pesticide products containing the subject active ingredient. The Agency has determined that the use of products containing ...

1986-01-01

165

Degradation of Fumigant Pesticides: 1,3-Dichloropropene, Methyl Isothiocyanate, Chloropicrin, and Methyl Bromide  

Microsoft Academic Search

is effective against nematodes, it lacks herbicidal activ- ity, and is often formulated with CP (e.g., Telone C17 Fumigant pesticides are frequently used in intensive agriculture and C35, which contain 17 and 35% CP, respectively) to control nematodes, fungi, and weeds. Currently, four registered fumigants are available: 1,3-dichloropropene (1,3-D), methyl isothio- to provide control of some fungal pathogens. Methyl cyanate

Robert S. Dungan; Scott R. Yates

2003-01-01

166

Microbial toxicity of pesticide derivatives produced with UV-photodegradation.  

PubMed

Our study aimed at acquiring information about the biological effect of pesticides and their degradates produced by UV-treatment on microbiological activity. Five photosensitive pesticides (carbendazim, acetochlor, simazine, chlorpyrifos, EPTC) and six representative soil microbes (Bacillus subtilis, Pseudomonas fluorescens, Mycobacterium phlei, Fusarium oxysporum, Penicillium expansum, Trichoderma harzianum) were applied throughout our model experiments. The antimicrobial effects of the pesticides and their degradates were assessed with filter paper disk method. The antimicrobial effect of the degradation products exhibited marked differences in terms of pesticide types, irradiation time, and the test organisms. Acetochlor and its photolytic degradation products were found to be more toxic to bacteria than fungi. All the three bacteria proved to be sensitive to the basic compound and its degradation products as well. The end product of carbendazim was weakly antibacterial against P. fluorescens and B. subtilis but strongly antifungal against T. harzianum. Chlorpyrifos and its end product inhibited neither test organisms, but the degradates hindered the growth of four of them. The basic compound of EPTC and the degradates of simazine exhibited significant toxicity to the test bacteria. It might be claimed that the pesticide photodegradation may result in significant changes in soil microbiota, as well as formation of biologically harmful degradates. PMID:17639315

Virág, Diána; Naár, Zoltán; Kiss, Attila

2007-07-17

167

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

PubMed

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

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

2012-07-11

168

Pesticides and health in highland Ecuadorian potato production: assessing impacts and developing responses.  

PubMed

Pesticide use in highland Ecuador is concentrated in the high-risk, commercial production of potatoes. Small farm families experience considerable exposure and adverse health consequences. The authors describe a three-pronged strategy to reduce health impacts: 1) a community-based process of education and provision of personal protective equipment to reduce exposure; 2) farmer field schools to increase agro-ecosystem understanding and to reduce pesticide use; and 3) policy interventions to restructure incentives and to reduce availability of highly toxic insecticides. They discuss the challenges faced by each and the ongoing need for integrated interventions both to reduce adverse pesticide health impacts in the developing world and to promote sustainability of agricultural production in highland ecosystems. PMID:12358074

Cole, Donald C; Sherwood, Stephen; Crissman, Charles; Barrera, Victor; Espinosa, Patrico

169

Pesticide residues in grapes, wine, and their processing products.  

PubMed

In this review the results obtained in the 1990s from research on the behavior of pesticide residues on grapes, from treatment to harvest, and their fate in drying, wine-making, and alcoholic beverage processing are reported. The fungicide residues on grapes (cyproconazole, hexaconazole, kresoxim-methyl, myclobutanil, penconazole, tetraconazole, and triadimenol), the application rates of which were of a few tens of grams per hectare, were very low after treatment and were not detectable at harvest. Pyrimethanil residues were constant up to harvest, whereas fluazinam, cyprodinil, mepanipyrim, azoxystrobin, and fludioxonil showed different disappearance rates (t(1/2) = 4.3, 12, 12.8, 15.2, and 24 days, respectively). The decay rate of the organophosphorus insecticides was very fast with t(1/2) ranging between 0.97 and 3.84 days. The drying process determined a fruit concentration of 4 times. Despite this, the residue levels of benalaxyl, phosalone, metalaxyl, and procymidone on sun-dried grapes equalled those on the fresh grape, whereas they were higher for iprodione (1.6 times) and lower for vinclozolin and dimethoate (one-third and one-fifth, respectively). In the oven-drying process, benalaxyl, metalaxyl, and vinclozolin showed the same residue value in the fresh and dried fruit, whereas iprodione and procymidone resides were lower in raisins than in the fresh fruit. The wine-making process begins with the pressing of grapes. From this moment onward, because the pesticide on the grape surface comes into contact with the must, it is in a biphasic system, made up of a liquid phase (the must) and a solid phase (cake and lees), and will be apportioned between the two phases. The new fungicides have shown no effect on alcoholic or malolactic fermentation. In some cases the presence of pesticides has also stimulated the yeasts, especially Kloeckera apiculata, to produce more alcohol. After fermentation, pesticide residues in wine were always smaller than those on the grapes and in the must, except for those pesticides that did not have a preferential partition between liquid and solid phase (azoxystrobin, dimethoate, and pyrimethanil) and were present in wine at the same concentration as on the grapes. In some cases (mepanipyrim, fluazinam, and chlorpyrifos) no detectable residues were found in the wines at the end of fermentation. From a comparison of residues in wine obtained by vinification with and without skins, it can be seen that their values were generally not different. Among the clarifying substances commonly used in wine (bentonite, charcoal, gelatin, polyvinylpolypyrrolidone, potassium caseinate, and colloidal silicon dioxide), charcoal allowed the complete elimination of most pesticides, especially at low levels, whereas the other clarifying substances were ineffective. Wine and its byproducts (cake and lees) are used in the industry to produce alcohol and alcoholic beverages. Fenthion, quinalphos, and vinclozolin pass into the distillate from the lees only if present at very high concentrations, but with a very low transfer percantage (2, 1, and 0.1%, respectively). No residue passed from the cake into the distillate, whereas fenthion and vinclozolin pass from the wine, but only at low transfer percentages (13 and 5%, respectively). PMID:10775335

Cabras, P; Angioni, A

2000-04-01

170

40 CFR 152.8 - Products that are not pesticides because they are not for use against pests.  

Code of Federal Regulations, 2013 CFR

...it is: (a) A fertilizer product not containing a pesticide. (b) A product intended to force bees from hives for the collection of honey crops. [53 FR 15975, May 4, 1988, as amended at 66 FR 64764, Dec. 14,...

2013-07-01

171

US EPA, Pesticide Product Label, PREVENTOL BIT 85, 01/15 ...  

EPA Pesticide Factsheets

... Date of Issuance: . U~~r~.d Term of Issuance: Conditional Name of Pesticide Product: Preventol BIT 85 ·~~1E~;if~~~~~t~~~~~I~:~~Ttit~~!~~ ...

2011-04-21

172

Analysis of Profitability of Synthetic and Naturally Occurring Pesticides in Solanecio biafrae Production  

Microsoft Academic Search

Vegetable farming offers opportunities for resource-poor farmers, because its production can be done with little capital investment. Pressure from pests reduces yields. Synthetic materials have been used to control pests, but there could be environmental problems associated with their use. Budgetary analysis was used to evaluate economics of naturally occurring and synthetic pesticides in Solanecio biafrae (Olive & Heirne) C.

A. A. Tijani; A. A. Akinola; N. A. Sofoluwe

2011-01-01

173

Development of smart spray systems to enhance delivery of pesticides in field nursery production  

Technology Transfer Automated Retrieval System (TEKTRAN)

Two smart sprayer prototypes have been developed and are being evaluated with a goal of increasing pesticide application efficiency and minimizing environmental impact in field nursery production sites. The first prototype, a modified hydraulic vertical boom system, utilizes ultrasonic sensors to d...

174

GLOBAL GENE EXPRESSION APPROACHES TO MODE-OF-ACTION STUDIES WITH NATURAL PRODUCT-BASED PESTICIDES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Natural products represent a vast repository of potential pesticides, some with novel molecular target sites. Whole-genome DNA microarrays seem a promising tool for identifying novel target sites, as microarrays enable monitoring the effects of a toxicant on the expression of every gene of an organ...

175

Sorption of pesticides by a mineral sand mining by-product, neutralised used acid (NUA).  

PubMed

This study investigated the sorption-desorption behaviour of four pesticides by a by-product from mineral sand mining, commonly referred to as neutralised used acid (NUA). In batch studies the average amount of pesticide removed after 6h was 69% for atrazine, 89% for diuron, 61% for 2,4-D and 83% for chlorpyrifos. The lower sorption of 2,4-D to NUA compared with the other pesticides studied is most likely to be due to the high pH of the solutions (7.8 to 8.8) which would have resulted in 2,4-D being predominantly in an anionic form. The presence of other pesticides only significantly decreased the amount of 2,4-D sorbed from 59% to 34% when present in a mixture. Little (2 to 17%) diuron, chlorpyrifos, atrazine or 2,4-D were found to desorb from the NUA. The presence of nitrate or phosphate had minimal effect on the amount of diuron or atrazine sorbed to the NUA. However, all phosphate and nitrate treatments significantly (P<0.05) decreased the amount of 2,4-D sorbed (<50%) compared with when 2,4-D was present alone (65%). This study has shown that NUA has potential to be used as a sorbent for pesticides. PMID:23178829

Oliver, Danielle P; Pan, Yi Fong; Anderson, Jenny S; Lin, Tsair Fuh; Kookana, Rai S; Douglas, Grant B; Wendling, Laura A

2012-11-22

176

78 FR 3418 - Pesticides; Draft Guidance for Pesticide Registrants on Web-Distributed Labeling for Pesticide...  

Federal Register 2010, 2011, 2012, 2013

...Draft Guidance for Pesticide Registrants on Web- Distributed Labeling for Pesticide Products...Registration Notice (PR Notice) titled ``Web-Distributed Labeling for Pesticide Products...labeling available through the Internet. Web-distributed labeling would allow...

2013-01-16

177

Adsorption, Movement, and Biological Degradation of Large Concentrations of Selected Pesticides in Soils.  

National Technical Information Service (NTIS)

Because of the importance of soil in biologically reducing the quantity and retarding the rate of pollutant movement into groundwater, this laboratory study was initiated to evaluate the adsorption, mobility, and degradation of large concentrations of the...

J. M. Davidson P. S. C. Rao L. T. Ou W. B. Wheeler D. F. Rothwell

1980-01-01

178

The Microbial Degradation of Aromatic Petroleum Products.  

National Technical Information Service (NTIS)

Pseudomonas Pxy was shown to oxidize para- and meta-xylene to the corresponding toluic acids. The latter compounds were oxidized to 4- and 3-methylcatechols prior to the enzymatic fission of the aromatic nucleus. Pathways are proposed for the degradation ...

D. T. Gibson

1977-01-01

179

Organophosphorus (OP) Pesticide Degradation in the Presence of Chlorinated Oxidants: Kinetics, Modeling, and Structure-Activity Relationships  

EPA Science Inventory

The rates and pathways for pesticide transformation during drinking water treatment are known for only a few pesticides and under limited conditions. The resulting oxons are more toxic than the parent pesticides. The transformation rates and pathways for chlorpyrifos, an OP pest...

180

Eleven-year trend in acetanilide pesticide degradates in the Iowa River, Iowa  

USGS Publications Warehouse

Trends in concentration and loads of acetochlor, alachlor, and metolachlor and their ethanasulfonic (ESA) and oxanilic (OXA) acid degradates were studied from 1996 through 2006 in the main stem of the Iowa River, Iowa and in the South Fork Iowa River, a small tributary near the headwaters of the Iowa River. Concentration trends were determined using the parametric regression model SEAWAVE-Q, which accounts for seasonal and flow-related variability. Daily estimated concentrations generated from the model were used with daily streamflow to calculate daily and yearly loads. Acetochlor, alachlor, metolachlor, and their ESA and OXA degradates were generally present in >50% of the samples collected from both sites throughout the study. Their concentrations generally decreased from 1996 through 2006, although the rate of decrease was slower after 2001. Concentrations of the ESA and OXA degradates decreased from 3 to about 23% yr-1. The concentration trend was related to the decreasing use of these compounds during the study period. Decreasing concentrations and constant runoff resulted in an average reduction of 10 to >3000 kg per year of alachlor and metolachlor ESA and OXA degradates being transported out of the Iowa River watershed. Transport of acetochlor and metolachlor parent compounds and their degradates from the Iowa River watershed ranged from <1% to about 6% of the annual application. These trends were related to the decreasing use of these compounds during the study period, but the year-to-year variability cannot explain changes in loads based on herbicide use alone. The trends were also affected by the timing and amount of precipitation. As expected, increased amounts of water moving through the watershed moved a greater percentage of the applied herbicides, especially the relatively soluble degradates, from the soils into the rivers through surface runoff, shallow groundwater inflow, and subsurface drainage.

Kalkhoff, Stephen J.; Vecchia, Aldo V.; Capel, Paul D.; Meyer, Michael T.

2012-01-01

181

Eleven-year trend in acetanilide pesticide degradates in the Iowa River, Iowa.  

PubMed

Trends in concentration and loads of acetochlor, alachlor, and metolachlor and their ethanasulfonic (ESA) and oxanilic (OXA) acid degradates were studied from 1996 through 2006 in the main stem of the Iowa River, Iowa and in the South Fork Iowa River, a small tributary near the headwaters of the Iowa River. Concentration trends were determined using the parametric regression model SEAWAVE-Q, which accounts for seasonal and flow-related variability. Daily estimated concentrations generated from the model were used with daily streamflow to calculate daily and yearly loads. Acetochlor, alachlor, metolachlor, and their ESA and OXA degradates were generally present in >50% of the samples collected from both sites throughout the study. Their concentrations generally decreased from 1996 through 2006, although the rate of decrease was slower after 2001. Concentrations of the ESA and OXA degradates decreased from 3 to about 23% yr. The concentration trend was related to the decreasing use of these compounds during the study period. Decreasing concentrations and constant runoff resulted in an average reduction of 10 to >3000 kg per year of alachlor and metolachlor ESA and OXA degradates being transported out of the Iowa River watershed. Transport of acetochlor and metolachlor parent compounds and their degradates from the Iowa River watershed ranged from <1% to about 6% of the annual application. These trends were related to the decreasing use of these compounds during the study period, but the year-to-year variability cannot explain changes in loads based on herbicide use alone. The trends were also affected by the timing and amount of precipitation. As expected, increased amounts of water moving through the watershed moved a greater percentage of the applied herbicides, especially the relatively soluble degradates, from the soils into the rivers through surface runoff, shallow groundwater inflow, and subsurface drainage. PMID:23099949

Kalkhoff, Stephen J; Vecchia, Aldo V; Capel, Paul D; Meyer, Michael T

182

Degradation product pattern and morphology changes as means to differentiate abiotically and biotically aged degradable polyethylene  

Microsoft Academic Search

Degradation product patterns and morphology changes are demonstrated to be means by which to differentiate between physical\\/chemical (abiotic) and biological (biotic) ageing of degradable polymers. Comparison is made between low-density polyethylene (LDPE), LDPE + 7.7% starch and LDPE + 20% (starch + pro-oxidant). Pro-oxidized samples were subjected to aqueous sterile and aqueous biotic (Arthrobacter paraffineus) environments at ambient temperatures for

Ann-Christine Albertsson; Camilla Barenstedt; Sigbritt Karlsson; Torbjörn Lindberg

1995-01-01

183

Photocatalytic degradation of pesticide pyridaben. 3. In surfactant/TiO2 aqueous dispersions.  

PubMed

The effective TiO2 photocatalytic degradation of pyridaben in an acetronitrile/water dispersion has been investigated in previous work, but could not be achieved in the case of real waters. In this paper, photocatalytic degradation of pyridaben on TiO2 particles under UV light (lambda> 360 nm) illumination in surfactant CTAB (cetyltrimethyl ammonium bromide) aqueous dispersions was studied. 1H NMR was used to determine quantitative information about the adsorption mode of pyridaben in CTAB micelles. The results showed that the upfield 1H shifts were largest for long chain protons of CTAB, indicating that the hydrophobic aromatic rings were primarily located in this region. Adsorption models on TiO2 surface were thus proposed. The reaction rates decreased with the increase of pH value, which can be attributed to the surface charge variations of pyridaben adsorbed onto TiO2 particles. The adsorption isotherms at different pH values confirmed that preadsorption on the surface of TiO2 particles was prerequisite for efficient degradation. Furthermore, an oxidation reagent such as H2O2 was added to the photocatalytic system, which may act as an alternative electron acceptor and result in a notably enhanced rate of pollutant destruction. On the basis of intermediates identified by GC/MS, a degradation pathway was proposed. PMID:17265957

Zhu, Xinle; Yuan, Chunwei; Chen, Huilan

2007-01-01

184

Leaching of azoxystrobin and its degradation product R234886 from Danish agricultural field sites.  

PubMed

The objective was to estimate leaching of the fungicide azoxystrobin (methyl (?E)-2-[[6-(2-cyanophenoxy)-4-pyrimidinyl]oxy]-?-(methoxymethylene)benzene-acetate) and one of its primary degradation products R234886 ([(E)-2-(2-[6-cyanophenoxy)-pyrimidin-4-yloxyl]-phenyl-3-methoxyacrylic acid], major fraction) at four agricultural research fields (one sandy and three loamy) in Denmark. Water was sampled from tile drains, suction cups and groundwater wells for a minimum period of two years after application of azoxystrobin. Neither azoxystrobin nor R234886 were detected at the sandy site, but did leach through loamy soils. While azoxystrobin was generally only detected during the first couple of months following application, R234886 leached for a longer period of time and at higher concentrations (up to 2.1?gL(-1)). Azoxystrobin is classified as very toxic to aquatic organisms and R234886 as very harmful. Our study shows that azoxystrobin and R234886 can leach through loamy soils for a long period of time following application of the pesticide and thereby pose a potential threat to vulnerable aquatic environments and drinking water resources. We thus recommend the inclusion of azoxystrobin and R234886 in pesticide monitoring programmes and further investigation of their long-term ecotoxicological effects. PMID:22497784

Jørgensen, Lisbeth Flindt; Kjær, Jeanne; Olsen, Preben; Rosenbom, Annette Elisabeth

2012-04-11

185

Bioaccumulation and degradation of pesticide fluroxypyr are associated with toxic tolerance in green alga Chlamydomonas reinhardtii  

Microsoft Academic Search

The herbicide fluroxypyr is widely used for controlling weeds and insects but intensive use of fluroxypyr has resulted in\\u000a its widespread contamination in soils and aquatic ecosystems. To evaluate the eco-toxicity of fluroxypyr to green algae, bioaccumulation\\u000a and degradation of fluroxypyr in Chlamydomonas reinhardtii, a model unicellular alga, along with its biological adaptation to fluroxypyr toxicity were investigated. The microalgae

Shuang ZhangChong; Chong Bin Qiu; You Zhou; Zhen Peng Jin; Hong Yang

2011-01-01

186

Iron (III) aquacomplexes as effective photocatalysts for the degradation of pesticides in homogeneous aqueous solutions  

Microsoft Academic Search

The degradation of the herbicide asulam (4-amino-benzosulfonyl-methylcarbamate) was studied by excitation of iron (III) aquacomplexes in aqueous solutions at 365 nm as well as by exposition to solar light. Sulfanilamide was also studied as a model molecule. The initial step of asulam disappearance was shown to be due to the formation of hydroxyl radicals generated from the excitation of Fe(OH)2+,

Carole Catastini; Mohamed Sarakha; Gilles Mailhot; Michèle Bolte

2002-01-01

187

Determination of organophosphorus pesticides and their transformation products in river waters by automated on-line solid-phase extraction followed by thermospray liquid chromatography-mass spectrometry.  

PubMed

The trace-level determination of ten priority organophosphorus (OP) pesticides (e.g., chlorpyrifos-methyl, diazinon, disulfoton, fenthion, fenamiphos) and various transformation products (TPs; e.g., disulfoton sulfoxide, fenthion sulfoxide etc.) using automated on-line solid-phase extraction (SPE) with C18 precolumns followed by LC-MS and thermospray interface with time-scheduled selected-ion monitoring (SIM) was developed. Two main ions (usually [M+H]+ and [M+NH4]+ or [M+CH3CN]+) were used for each pesticide in the positive ion (PI) detection mode, while [M-H]- and [M+HCOO]- ions were used in the negative ion (NI) mode. The proposed method requires 100 ml of sample for a limit of detection (LOD) of 0.01-0.1 microgram/l. Calibration graphs were constructed by preconcentrating 100 ml of water spiked with the pesticide mixture at various concentrations (from 0.025 to 2 microgram/l). Good linearity was observed for most of the analytes studied. The experimental setup described in this paper was applied to study the kinetics of degradation of ten organophosphorus pesticides in spiked river water samples. The different samples were first analyzed by an automated on-line precolumn exchange system (OSP-2) followed by LC with diode array detection. To confirm the identity of the organophosphorus pesticides detected, the samples were then analyzed by automated on-line SPE-LC-MS. The method permitted unequivocal identification of many of the TPs formed during the experiments, e.g., the oxo-derivatives of chlorpyrifos-methyl, temephos and pyridafenthion, fenamiphos sulfoxide. Many of these TPs are here reported for the first time since previously used MS-based techniques were not sensitive enough. PMID:8556144

Lacorte, S; Barceló, D

1995-09-29

188

Guidance for the Reregistration of Pesticide Products Containing Boric Acid and Boron Containing Salts as the Active Ingredient.  

National Technical Information Service (NTIS)

The document contains information regarding the reregistration of pesticide products containing the subject active ingredient. The document includes how to register under a registration standard, regulatory position and rationale, and summaries of data re...

1985-01-01

189

Guidance for the Reregistration of Pesticide Products Containing Oxytetracycline, Oxytetracycline Hydrochloride and Oxytetracycline Calcium Complex as the Active Ingredient.  

National Technical Information Service (NTIS)

The document contains information regarding the registration of pesticide products containing oxytetracycline, oxytetracycline hydrochloride or oxytetracycline calcium complex. The document includes how to register under a registration standard, regulator...

1988-01-01

190

Thermally induced degradation of aliphatic glucosinolates: identification of intermediary breakdown products and proposed degradation pathways.  

PubMed

In Brassica vegetables, heating processes lead to thermally induced degradation of glucosinolates (GSLs), resulting in the formation of nitriles and isothiocyanates (ITCs). To date, the mechanism is not yet satisfyingly elucidated. Thermally induced degradation of the model GSL sinigrin was studied in dry as well as aqueous medium at different pH values and temperatures. The influence of the presence of iron ions and plant matrix (broccoli sprouts powder) on the degradation was studied as well. Next to the degradation of the GSL, the formation of nitrile and ITC and the release of sugar derivatives were investigated. Because d-glucose and ITC are main thermal breakdown products under aqueous conditions, hydrolysis seems to be the initial step in the degradation pathway during cooking. In contrast, under dry conditions, the desulfo-sinigrin was identified as a main intermediary thermal breakdown product for the first time. Further, degradation of the desulfo-GSL results in the release of d-thioglucose and the corresponding nitrile. Iron(II) ions and plant matrix influence the thermal stability of the GSL and favor the formation of nitriles. PMID:22958137

Hanschen, Franziska S; Bauer, Anna; Mewis, Inga; Keil, Claudia; Schreiner, Monika; Rohn, Sascha; Kroh, Lothar W

2012-09-19

191

Multiresidue determination of pesticides in agricultural products by gas chromatography/mass spectrometry with large volume injection.  

PubMed

A method is described for the rapid determination of pesticide residues in agricultural products. Pesticides were extracted from samples with acetonitrile. To remove pigments and fatty acids, an aliquot of the extract was cleaned up by a minicolumn that was packed both with graphitized carbon black and primary secondary amine. Analysis was performed by gas chromatography/ mass spectrometry with programmable temperature vaporizer-based large volume injection using a liner packed with phenylmethylsilicone chemically bonded silica. The method was evaluated for 114 pesticides by spiking into tomato, spinach, Japanese pear, grape, and brown rice at various concentrations of each pesticide (0.02-0.4 microg/g). The method, which gave good recovery (>60%) for 108 pesticides, is characterized by high cleanup efficiency and short cleanup time, and is useful as a rapid screening analysis. PMID:15675447

Saito, Yukio; Kodama, Shuji; Matsunaga, Akinobu; Yamamoto, Atsushi

192

Atrazine degradation by anodic Fenton treatment.  

PubMed

Anodic Fenton treatment (AFT), an hydroxyl radical oxidation process recently developed for the degradation of aqueous pesticide waste, was applied to the degradation of atrazine, seven degradation products, and a formulated atrazine product. Using AFT, degradation of the parent compound occurred in 3 min. The concentration profiles of seven degradation products formed during treatment were measured, and degradation pathways are proposed for the treatment. The primary termination product after 10 min was dechlorinated ammeline. Three different 14C labeled atrazine compounds (ethyl, isopropyl and U-triazine ring labeled atrazine) were also treated in an air-tight AFT apparatus and the mass balance was calculated. The triazine ring was not cleaved during this treatment process. Formulated atrazine was 70% degraded in 3 min. AFT holds promise as an effective pesticide-laden water treatment technology. PMID:12448559

Saltmiras, David A; Lemley, Ann T

2002-12-01

193

A study of the products of PVC thermal degradation  

Microsoft Academic Search

PVC thermal degradation in vacuum up to 500 °C has been followed by recording the relative rate of volatile product formation by thermal volatilisation analysis while monitoring by mass spectrometry the formation of the main products: HCl, aromatic and aliphatic hydrocarbons, and non-condensable gases (CH4, H2). The material balance after pyrolysis has been evaluated. The liquid fraction collected during pyrolysis

Ian C. McNeill; Livia Memetea; William J. Cole

1995-01-01

194

Exposures of preschool children to chlorpyrifos and its degradation product 3,5,6-trichloro-2-pyridinol in their everyday environments  

Microsoft Academic Search

As part of the Children's Total Exposure to Persistent Pesticides and Other Persistent Organic Pollutants (CTEPP) study, we investigated the exposures of preschool children to chlorpyrifos and its degradation product 3,5,6-trichloro-2-pyridinol (TCP) in their everyday environments. During this study, the participants were still able to purchase and apply chlorpyrifos at their homes or day care centers. Participants were recruited randomly

Marsha K Morgan; Linda S Sheldon; Carry W Croghan; Paul A Jones; Gary L Robertson; Jane C Chuang; Nancy K Wilson; Christopher W Lyu

2005-01-01

195

DEGRADATION AND MIGRATION OF VINCLOZOLIN IN SAND AND SOIL  

EPA Science Inventory

The migration of the dicarboximide fungicide vinclozolin and its principal degradation products through porous media was experimentally determined by simulating pesticide applications to a 23-30 mesh Ottawa sand and a North Carolina Piedmont, aquic hapludult soil in laboratory ...

196

Solvent degradation products in nuclear fuel processing solvents  

SciTech Connect

The Savannah River Plant uses a modified Purex process to recover enriched uranium and separate fission products. This process uses 7.5% tri-n-butyl phosphate (TBP) dissolved in normal paraffin hydrocarbons for the solvent extraction of a nitric acid solution containing the materials to be separated. Periodic problems in product decontamination result from solvent degradation. A study to improve process efficiency has identified certain solvent degradation products and suggested mitigation measures. Undecanoic acid, lauric acid, and tridecanoic acid were tentatively identified as diluent degradation products in recycle solvent. These long-chain organic acids affect phase separation and lead to low decontamination factors. Solid phase extraction (SPE) was used to concentrate the organic acids in solvent prior to analysis by high performance liquid chromatography (HPLC). SPE and HPLC methods were optimized in this work for analysis of decanoic acid, undecanoic acid, and lauric acid in solvent. Accelerated solvent degradation studies with 7.5% TBP in normal paraffin hydrocarbons showed that long-chain organic acids and long-chain alkyl butyl phosphoric acids are formed by reactions with nitric acid. Degradation of both tributyl phosphate and hydrocarbon can be minimized with purified normal paraffin replacing the standard grade presently used. 12 refs., 1 fig., 3 tabs.

Shook, H.E. Jr.

1988-06-01

197

Photosensitized degradation in water of the phenolic pesticides bromoxynil and dichlorophen in the presence of riboflavin, as a model of their natural photodecomposition in the environment.  

PubMed

Within the context of environmentally friendly methods for the elimination of surface-water pollutants, the photodegradation of the phenolic pesticides bromoxynil (BXN) and dichlorophen (DCP) under simulated natural conditions has been studied. The work was done in the presence of the visible-light absorber photosensitizer riboflavin (Rf), usually present in trace quantities in natural waters. Under aerobic conditions, an efficient photooxidation of both pesticides was observed. The relatively intricate photochemical mechanism involves pesticide and oxygen consumption and, to a lesser extent, Rf degradation. The kinetic and mechanistic study supports that both H(2)O(2) and singlet molecular oxygen, O(2)((1)?(g)), are involved in the process. Kinetic data for the O(2)((1)?(g))-mediated oxidation indicate that BXN and DCP are photodegraded with this species faster than the parent compound phenol, very frequently employed as a model for aquatic contaminants, likely due to their lower pK(a) values. This observation allows the design of phenolic pesticides with different photodegradation rates under environmental conditions. PMID:21130569

Escalada, Juan P; Pajares, Adriana; Gianotti, José; Biasutti, Alicia; Criado, Susana; Molina, Patricia; Massad, Walter; Amat-Guerri, Francisco; García, Norman A

2010-11-12

198

Non-occupational exposures to pesticides for residents of two U.S. cities  

Microsoft Academic Search

The Non-Occupational Pesticide Exposure Study, funded by the U.S. Environmental Protection Agency, was designed to assess total human exposures to 32 pesticides and pesticide degradation products in the non-occupational environment; however, the study focused primarily on inhalation exposures. Two sites—Jacksonville, Florida (USA) and Springfield\\/Chicopee, Massachusetts (USA)—were studied during three seasons: Summer 1986 (Jacksonville only), Spring 1987, and Winter 1988. Probability

R. W. Whitmore; F. W. Immerman; D. E. Camann; A. E. Bond; R. G. Lewis; J. L. Schaum

1994-01-01

199

Air pollution and young children's inhalation exposure to organophosphorus pesticide in an agricultural community in Japan  

Microsoft Academic Search

Assessment of airborne organophosphorus pesticides in houses of young children (1–6 years old) and childcare facilities was conducted following pesticide applications in an agricultural community in Japan. Trichlorfon and fenitrothion, applied in two separate periods, were frequently detected from outdoor and indoor air. Dichlorvos, the primary degradation product of trichlorfon, was also detected after the application of trichlorfon. Both the

Junko Kawahara; Ryoko Horikoshi; Takashi Yamaguchi; Kazukiyo Kumagai; Yukio Yanagisawa

2005-01-01

200

Photochemical fluorimetric analysis of phenylbutazone and its degradation products.  

PubMed

A room temperature photochemical spectrofluorimetric (RTPF) method has been developed for the assay of phenylbutazone (PB), and its major degradation products. Fluorescence spectral properties of PB, its degradation products, and their photoproducts are reported, as well as the optimal irradiation times (ranging from 4 to 45 min), which correspond to maximum fluorescence signals of photoproducts. Linear log-log calibration plots were obtained over a 50- to 1000-fold range of concentration, and limits of detection ranged between 1 ng/ml and 1.2 micrograms/ml. This has been shown to be a convenient technique, in terms of simplicity, short measurement times, sensitivity, and precision. PMID:2490547

Fricoteaux, R; Aaron, J J; Quaglia, M G

1989-01-01

201

Phosphate and soil binding: factors limiting bacterial degradation of ionic phosphorus-containing pesticide metabolites.  

PubMed Central

Soils that had a high binding capacity for inorganic orthophosphate (Pi) had reduced capacities to bind ionic alkyl phosphorus compounds. Only ionic methylphosphonate (MPn) and ionic phenylphosphonate exhibited moderate binding. Pseudomonas testosteroni used either MPn or Pi as a sole phosphorus source and exhibited diauxic utilization of MPn and Pi. The utilization of MPn was suppressed in the presence of Pi. This suppression was abolished by a Pi-binding soil. The soil did not have a significant effect on the maximum rate of degradation of either MPn or the poorly bound ionic O-isopropyl methylphosphonate, whereas the amount of MPn (but not the amount of O-isopropyl methylphosphonate) metabolized was reduced in the presence of soil

Daughton, C G; Cook, A M; Alexander, M

1979-01-01

202

Identification and measurement of pesticide contaminants in food products by electron impact GC/MS  

NASA Astrophysics Data System (ADS)

The paper concern is determination of eight pesticides in food products samples. The target compounds are: Lindane, Heptachlor, Aldrin, o,p-DDE, Dieldrin, Endrin, p,p'-DDT, and Methoxychlor. The compounds quantities were performed from chromatographic area obtained in full scan GC/MS mode after baseline separation and by comparation with surrogate internal standard area (Diphenylamine). The samples were concentrated by extraction with organic solvents (acetone) by Solid-Liquid Extraction (SLE) procedures the recovery factors being better than 80% except for Heptachlors. The coefficient of correlation of detector response function was better than 0.913 and LOQ under 0.015 ?g/g. The method enables to determine pesticides at low ?g/g in food supplements.

Tusa, Florina; Moldovan, Zaharie; Vlassa, Mircea

2009-08-01

203

US EPA, Pesticide Product Label, TILT GEL FUNGICIDE, 04 ...  

EPA Pesticide Factsheets

... DIB'lB)'1 18 EPA R;~~\\~ni~~~~;7 ,. .:' Tilt Gel Fungicide ~ .. -: ... A stamped copy for each product, Tilt ~ ~~~~ Gel, is enclosed for your records. ...

2011-04-13

204

77 FR 75155 - Product Cancellation Order for Certain Pesticide Registrations  

Federal Register 2010, 2011, 2012, 2013

...products permitting use on cotton, dry beans, peanut, soybean, sugar beets...Temik 15G labeled for use on cotton, dry beans, peanut, soybean, sugar beets...Temik 15G labeled for use on cotton, dry beans, peanut, soybean, sugar...

2012-12-19

205

Pesticide use in banana and plantain production and risk perception among local actors in Talamanca, Costa Rica  

SciTech Connect

The Talamanca County in Costa Rica has large-scale banana and small-scale plantain production, probably causing pesticide exposure in indigenous children. We explored to what extent different community actors are aware of children's pesticide hazards and how their awareness related to socio-economical and cultural conditions. Methods comprised eight focus groups with fathers and mothers separately, 27 semi-structured interviews to key actors, and field observations. As a whole, the indigenous plantain farmers and banana plantation workers had some general knowledge of pesticides concerning crop protection, but little on acute health effects, and hardly any on exposure routes and pathways, and chronic effects. People expressed vague ideas about pesticide risks. Inter-community differences were related to pesticide technologies used in banana and plantain production, employment status on a multinational plantation versus smallholder status, and gender. Compared to formalized practices on transnational company plantations, where workers reported to feel protected, pesticide handling by plantain smallholders was not perceived as hazardous and therefore no safety precautions were applied. Large-scale monoculture was perceived as one of the most important problems leading to pesticide risks in Talamanca on banana plantations, and also on neighboring small plantain farms extending into large areas. Plantain farmers have adopted use of highly toxic pesticides following banana production, but in conditions of extreme poverty. Aerial spraying in banana plantations was considered by most social actors a major determinant of exposure for the population living nearby these plantations, including vulnerable children. We observed violations of legally established aerial spraying distances. Economic considerations were most mentioned as the underlying reason for the pesticide use: economic needs to obtain the production quantity and quality, and pressure to use pesticides by other economic agents such as middlemen. Risk perceptions were modulated by factors such as people's tasks and positions in the production process, gender, and people's possibilities to define their own social conditions (more fatalistic perceptions among banana workers). The challenge for the future is to combine these insights into improved health risk assessment and management that is culturally adequate for each particular community and agricultural context. - Research highlights: {yields} A first study on pesticide risk perception in Costa Rica. {yields} One of the few studies performed in the indigenous populations in Talamanca. {yields} Economic considerations prevailed above health risks in both communities. {yields} Our findings provide valuable information for multiple social actors.

Barraza, Douglas, E-mail: dbarraza@una.ac.cr [Central American Institute for Studies on Toxic Substances, Universidad Nacional, Heredia (Costa Rica) [Central American Institute for Studies on Toxic Substances, Universidad Nacional, Heredia (Costa Rica); Technology and Agrarian Development Group, Wageningen University (Netherlands); Jansen, Kees [Technology and Agrarian Development Group, Wageningen University (Netherlands)] [Technology and Agrarian Development Group, Wageningen University (Netherlands); Wendel de Joode, Berna van; Wesseling, Catharina [Central American Institute for Studies on Toxic Substances, Universidad Nacional, Heredia (Costa Rica)] [Central American Institute for Studies on Toxic Substances, Universidad Nacional, Heredia (Costa Rica)

2011-07-15

206

Pesticide occurrence in groundwater in areas of high-density row crop production in Alabama, 2009  

USGS Publications Warehouse

High-density row crop production occurs in three areas of Alabama that are underlain by productive aquifers, northern Alabama, southeastern Alabama, and Baldwin County in southwestern Alabama. The U.S. Geological Survey collected five groundwater samples from each of these three areas during 2009 for analysis of selected pesticides. Results of these analyses showed detections for 37 of 152 analytes. The three most frequently detected compounds were atrazine, 2-Chloro-4-isopropylamino-6-amino-triazine (CIAT), and metolachlor. The highest concentration for any analyte was 4.08 micrograms per liter for metolachlor.

Moreland, Richard S.

2011-01-01

207

Effect of Pesticide Inoculation, Duration of Composting, and Degradation Time on the Content of Compost Fatty Acids, Quantified Using Two Methods ? †  

PubMed Central

Compost biobeds can promote biodegradation of pesticides. The microbial community structure changes during the composting process, and simple methods can potentially be used to follow these changes. In this study the microbial identification (MIDI) and ester-linked (EL) procedures were used to determine the composition of fatty acid methyl esters (FAMEs) in composts aged 3 and 12 months, inoculated with 3 recalcitrant pesticides (azoxystrobin, chlorotoluron, and epoxyconazole and a coapplication of all three) after 0, 56, and 125 days of degradation. Pesticide persistence was high, and after 125 days the residue was 22 to 70% of the applied amount depending mostly on the composting age. Seventy-one FAMEs belonging to nine groups were detected. The EL method provided three times as many detections as did the MIDI method and was more sensitive for all FAME groups except alcohol. Thirty-six and five FAMEs were unique to the EL and MIDI methods, respectively. The extraction method was of importance. The EL method provided a higher number of detections for 57 FAMEs, and the MIDI method provided a higher number for 9 FAMEs, while the two methods were equal for 5 FAMEs; thus, the EL method provided a more uniform overall FAME profile. Effects of the other factors were not always clear. Inoculation with pesticide did not influence the FAME profile with the MIDI method, while it influenced cyclopropane and monounsaturated content with the EL method. Composting age and degradation time had an effect on some groups of FAMEs, and this effect was greater with the EL method. The use of some FAMEs as biomarkers to follow microbial community succession was likely influenced by the type of compost and other factors.

Cardinali, Alessandra; Otto, Stefan; Vischetti, Costantino; Brown, Colin; Zanin, Giuseppe

2010-01-01

208

Effect of pesticide inoculation, duration of composting, and degradation time on the content of compost fatty acids, quantified using two methods.  

PubMed

Compost biobeds can promote biodegradation of pesticides. The microbial community structure changes during the composting process, and simple methods can potentially be used to follow these changes. In this study the microbial identification (MIDI) and ester-linked (EL) procedures were used to determine the composition of fatty acid methyl esters (FAMEs) in composts aged 3 and 12 months, inoculated with 3 recalcitrant pesticides (azoxystrobin, chlorotoluron, and epoxyconazole and a coapplication of all three) after 0, 56, and 125 days of degradation. Pesticide persistence was high, and after 125 days the residue was 22 to 70% of the applied amount depending mostly on the composting age. Seventy-one FAMEs belonging to nine groups were detected. The EL method provided three times as many detections as did the MIDI method and was more sensitive for all FAME groups except alcohol. Thirty-six and five FAMEs were unique to the EL and MIDI methods, respectively. The extraction method was of importance. The EL method provided a higher number of detections for 57 FAMEs, and the MIDI method provided a higher number for 9 FAMEs, while the two methods were equal for 5 FAMEs; thus, the EL method provided a more uniform overall FAME profile. Effects of the other factors were not always clear. Inoculation with pesticide did not influence the FAME profile with the MIDI method, while it influenced cyclopropane and monounsaturated content with the EL method. Composting age and degradation time had an effect on some groups of FAMEs, and this effect was greater with the EL method. The use of some FAMEs as biomarkers to follow microbial community succession was likely influenced by the type of compost and other factors. PMID:20693445

Cardinali, Alessandra; Otto, Stefan; Vischetti, Costantino; Brown, Colin; Zanin, Giuseppe

2010-08-06

209

Plasma cross linked fibrin degradation products in pulmonary embolism.  

PubMed Central

Plasma concentrations of cross linked fibrin degradation products, a marker of intravascular thrombosis and fibrinolysis, were measured in 495 patients with suspected pulmonary embolism referred for ventilation-perfusion lung scanning to determine whether concentrations are increased in pulmonary embolism and their potential use in diagnosis. Lung scans were described as normal (n = 66) or as showing a low (n = 292), indeterminate (n = 58), or high probability (n = 79) of pulmonary embolism. There was a difference between the mean levels of cross linked fibrin degradation products in each scan category: normal scans, 142 ng/ml; low probability scans, 295 ng/ml; indeterminate probability scans, 510 ng/ml; high probability scans, 952 ng/ml (p less than 0.001). Of the patients with high probability scans, 96% had raised concentrations. Explanations for discrepant low results include incorrect scan diagnosis, delay in blood sampling, and anticoagulation. Of the patients with a low or indeterminate probability of pulmonary embolism, 43% had increased concentrations of cross linked fibrin degradation products that could be attributed in most cases to another illness. Owing to the wide range of values in each lung scan diagnostic category, raised concentrations of these fibrin degradation products cannot be used without reference to the patient's clinical state as a discriminatory test for pulmonary embolism. Further evaluation of the significance of normal concentrations in excluding a diagnosis of pulmonary embolism appears to be warranted.

Rowbotham, B J; Egerton-Vernon, J; Whitaker, A N; Elms, M J; Bunce, I H

1990-01-01

210

US EPA, Pesticide Product Label, PERMETHRIN 0.25% ...  

EPA Pesticide Factsheets

... No 1662-G poiSon control center, or doctor, or when going for ... Sears It is a violation of federal law to use this product in ... fl;~~I~;j;~~,d~;dr~~v~~~~rr2 ...

2011-04-21

211

75 FR 16109 - Antimicrobial Pesticide Products; Registration Applications  

Federal Register 2010, 2011, 2012, 2013

...by statute. Certain other material, such as copyrighted material, is not placed on the Internet...Publicly available docket materials are available either in the...plastic and wood protection stains. Contact: Jacqueline Campbell-McFarlane...polymers, latex products, and ceramics. Contact: Demson...

2010-03-31

212

US EPA, Pesticide Product Label, , 06/30/2003  

EPA Pesticide Factsheets

... This ~~~~~i ~~~t~in's' 4.76% ~~'Ybd~~~'; d~ri~~d 'f~~';' di~~·,;Ybd~i~ .... A' This product contains the toxic inert ingredient Rhodamine B. ...

2011-04-21

213

76 FR 40359 - Product Cancellation Order for Certain Pesticide Registrations  

Federal Register 2010, 2011, 2012, 2013

...Root Endz.... Copper sulfate pentahydrate...number Product name Chemical name...N-dimethyl- Bacteriostat (10%). , chloride...Alkyl* dimethyl Microbiocide. benzyl ammonium...Amvac Chemical Corporation...Great Lakes Chemical Corporation...H & S Chemicals Division, c...Suite 200, Burr Ridge, IL 60527....

2011-07-08

214

US EPA, Pesticide Product Label, 5% SEVIN-COPPER ...  

EPA Pesticide Factsheets

... This product is hif'hl~' tm;ic ill hI'I"'; l'''pltst'd tr> d!rt,(,t ! rt'atrn('lli tlr n'·;idu'~ un ('np:-., Pritt, ,'li\\'p Ilt!(lrnli'ti''11 ILl,.\\ lit' ,)ilLti!II'd fUTln ~'()llr COOp('rilll ...

2011-04-14

215

Monitoring of toxicity during degradation of selected pesticides using ionizing radiation.  

PubMed

The optimization of experimental conditions for radiolytic removal of organic pollutants from water and waste with the use of ionizing radiation via controlling the concentration of target compound(s) requires also monitoring the toxicity changes during the process. Commonly used herbicides 2,4-D and dicamba were shown to increase toxicity measured with the Microtox test at low irradiation doses resulting from formation of more toxic transient products, which can be decomposed at larger doses. The changes of toxicity were examined with respect to dose magnitude and the presence of commonly occurring scavengers of radiation. PMID:15294437

Drzewicz, Przemys?aw; Na?ecz-Jawecki, Grzegorz; Gryz, Micha?; Sawicki, Józef; Bojanowska-Czajka, Anna; G?uszewski, Wojciech; Kulisa, Krzysztof; Wo?kowicz, Stanis?aw; Trojanowicz, Marek

2004-10-01

216

Production and degradation of polyhydroxyalkanoates in waste environment  

SciTech Connect

Polyhydroxyalkanoates (PHAs) are energy/carbon storage materials accumulated under unfavorable growth condition in the presence of excess carbon source. PHAs are attracting much attention as substitute for non-degradable petrochemically derived plastics because of their similar material properties to conventional plastics and complete biodegradability under natural environment upon disposal. In this paper, PHA production and degradation in waste environment as well as its role in biological phosphorus removal are reviewed. In biological phosphorus removal process, bacteria accumulating polyphosphate (poly P) uptake carbon substrates and accumulate these as PHA by utilizing energy from breaking down poly P under anaerobic conditions. In the following aerobic condition, accumulated PHA is utilized for energy generation and for the regeneration of poly P. PHA production from waste has been investigated in order to utilize abundant organic compounds in waste water. Since PHA content and PHA productivity that can be obtained are rather low, PHA production from waste product should be considered as a coupled process for reducing the amount of organic waste. PHAs can be rapidly degraded to completion in municipal anaerobic sludge by various microorganisms.

Lee, S.Y.; Choi, J. [Korea Advanced Inst. of Science and Technology, Taejon (Korea, Republic of)

1999-06-01

217

Pesticide use in banana and plantain production and risk perception among local actors in Talamanca, Costa Rica.  

PubMed

The Talamanca County in Costa Rica has large-scale banana and small-scale plantain production, probably causing pesticide exposure in indigenous children. We explored to what extent different community actors are aware of children's pesticide hazards and how their awareness related to socio-economical and cultural conditions. Methods comprised eight focus groups with fathers and mothers separately, 27 semi-structured interviews to key actors, and field observations. As a whole, the indigenous plantain farmers and banana plantation workers had some general knowledge of pesticides concerning crop protection, but little on acute health effects, and hardly any on exposure routes and pathways, and chronic effects. People expressed vague ideas about pesticide risks. Inter-community differences were related to pesticide technologies used in banana and plantain production, employment status on a multinational plantation versus smallholder status, and gender. Compared to formalized practices on transnational company plantations, where workers reported to feel protected, pesticide handling by plantain smallholders was not perceived as hazardous and therefore no safety precautions were applied. Large-scale monoculture was perceived as one of the most important problems leading to pesticide risks in Talamanca on banana plantations, and also on neighboring small plantain farms extending into large areas. Plantain farmers have adopted use of highly toxic pesticides following banana production, but in conditions of extreme poverty. Aerial spraying in banana plantations was considered by most social actors a major determinant of exposure for the population living nearby these plantations, including vulnerable children. We observed violations of legally established aerial spraying distances. Economic considerations were most mentioned as the underlying reason for the pesticide use: economic needs to obtain the production quantity and quality, and pressure to use pesticides by other economic agents such as middlemen. Risk perceptions were modulated by factors such as people's tasks and positions in the production process, gender, and people's possibilities to define their own social conditions (more fatalistic perceptions among banana workers). The challenge for the future is to combine these insights into improved health risk assessment and management that is culturally adequate for each particular community and agricultural context. PMID:21396636

Barraza, Douglas; Jansen, Kees; van Wendel de Joode, Berna; Wesseling, Catharina

2011-03-10

218

The Greening of Pesticide-Environment Interactions: Some Personal Observations  

PubMed Central

Background: Pesticide–environment interactions are bidirectional. The environment alters pesticides by metabolism and photodegradation, and pesticides in turn change the environment through nontarget or secondary effects. Objectives: Approximately 900 currently used commercial pesticides of widely diverse structures act by nearly a hundred mechanisms to control insects, weeds, and fungi, usually with minimal disruption of nature’s equilibrium. Here I consider some aspects of the discovery, development, and use of ecofriendly or green pesticides (i.e., pesticides that are safe, effective, and biodegradable with minimal adverse secondary effects on the environment). Emphasis is given to research in my laboratory. Discussion: The need for understanding and improving pesticide–environment interactions began with production of the first major insecticide approximately 150 years ago: The arsenical poison Paris Green was green in color but definitely not ecofriendly. Development and use of other pesticides has led to a variety of problems. Topics considered here include the need for high purity [e.g., hexachlorocyclohexane and polychloroborane isomers and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T)], environmental degradation and the bioactivity of resulting photoproducts and metabolites, pesticide photochemistry (including the use of structural optimization, photostabilizers, and photosensitizers to achieve suitable persistence), the presence of multiple active ingredients in botanical insecticides, the need to consider compounds with common mechanisms of action, issues related to primary and secondary targets, and chemically induced or genetically modified changes in plant biochemistry. Many insecticides are bird, fish, and honeybee toxicants, whereas herbicides and fungicides pose fewer environmental problems. Conclusion: Six factors have contributed to the greening of pesticide–environment interactions: advances in pesticide chemistry and toxicology, banning of many chlorinated hydrocarbons, the development of new biochemical targets, increased reliance on genetically modified crops that reduce the amount and variety of pesticides applied, emphasis on biodegradability and environmental protection, and integrated pest- and pesticide-management systems.

2012-01-01

219

Routine low-level monitoring of polar pesticides and pesticide degradates by HPLC/ESI-MS: Evaluating long-term performance  

USGS Publications Warehouse

The sensitivity and selective determination of polar pesticides were analyzed using high-performance liquid chromatography/electrospray ionization-mass spectrometry (HPLC/ESI-MS). The effects of multiple operators and instruments on method performance were evaluated using 440 pairs of fortified reagent-water and blank reagent-water samples. The influence of varying environmental matrices on recovery and precision were also analyzed using 200 fortified ambient water samples and duplicate ambient water samples. The results show that compound stability in filtered water was matrix-, chemical class- and compound-dependent which ranged from 1 day to 2 weeks.

Furlong, E. T.; Martin, J. D.; Werner, S. L.; Gates, P. M.

2002-01-01

220

Determination of bronopol and its degradation products by HPLC.  

PubMed

Bronopol (2-bromo-2-nitropropane-1,3-diol) is widely used as an anti-microbial in cosmetics, external medicaments, shampoos and bath preparations. A reversed-phase high performance liquid chromatographic separation method with UV spectrophotometric detection was developed for the determination of bronopol and its degradation products. Degradation of bronopol was observed in aqueous medium, giving rise to non-reproducible data. To overcome this problem, HPLC grade methanol (water content <0.05%) was used for sample preparation. In addition, the parameters for the HPLC analysis of bronopol were optimised. It was found that bronopol standards and product samples were stable in methanol for at least 1 month at ambient temperature, thus allowing a quantitative and reproducible determination of bronopol. PMID:12062701

Wang, Huafu; Provan, Gordon J; Helliwell, Keith

2002-06-20

221

Development of automated online gel permeation chromatography-gas chromatograph mass spectrometry for measuring multiresidual pesticides in agricultural products.  

PubMed

An automated online gel permeation chromatography-gas chromatograph mass spectrometer (GPC-GC/MS) was developed for the rapid determination of residual pesticides in agricultural products. Pesticides were extracted from homogenized food samples with acetonitrile and decontaminated via the matrix solid-phase dispersion (MSPD) technique, using a primary secondary amine as sorbent prior to GPC-GC/MS analysis. A slightly modified preparation method and automated GPC step proved useful in minimizing matrix interference. To evaluate the performance of the system, 97 target pesticides were spiked at a concentration of 0.1mg/kg into a range of food types, including potato, cabbage, carrot, apple, orange, cucumber, and rice. A low flow rate of 0.1 mL/min in GPC resulted in a 40-fold reduction in solvent consumption compared with conventional GPC column applications. The combination of MSPD technique and GPC-GC/MS for the analysis of the 97 pesticides can be accomplished within 90 min. Most pesticides were recovered in the range of 70-120%, with relative standard deviation generally less than 10%. The results demonstrate that the method can be successfully applied with acceptable recoveries to a broad range of target pesticides within a diverse range of food types. PMID:16931180

Liu, Li-Bin; Hashi, Yuki; Qin, Ya-Ping; Zhou, Hai-Xia; Lin, Jin-Ming

2006-08-23

222

40 CFR 152.8 - Products that are not pesticides because they are not for use against pests.  

Code of Federal Regulations, 2011 CFR

...defined in § 152.5, if it is: (a) A fertilizer product not containing a pesticide. (b) A product intended to force bees from hives for the collection of honey crops. [53 FR 15975, May 4, 1988, as amended at 66 FR 64764, Dec. 14,...

2011-07-01

223

Imazalil Degradation upon Applying Ozone—Transformation Products, Kinetics, and Toxicity of Treated Aqueous Solutions  

Microsoft Academic Search

The elimination of the pesticide imazalil (IMZ) spiked into ultrapure water as well as into wastewater applying ozone (O3) and the identification of transformation products was investigated. O3 under hydroxyl radical suppression conditions reacted rapidly with the aliphatic double bond or the imidazole ring in IMZ, yielding several transformation products by partial oxidation. The structures of four oxidation products not

Aziza K. Genena; Danielle B. Luiz; Wilhelm Gebhardt; Regina F. P. M. Moreira; Humberto J. José; Horst Fr. Schröder

2011-01-01

224

DETERMINATION OF INTERFERING TRIAZINE DEGRADATION PRODUCTS BY GAS CHROMATOGRAPHY-ION TRAP MASS SPECTROMETRY  

EPA Science Inventory

Deethyl atrazine (DEA), along with other triazine degradation products, has been added to the US Environmental Protection Agency's Drinking Water Contaminant Candidate List (CCL). In its gas chromatographic (GC) analysis, deethyl atrazine, a degradation product of atrazine, can ...

225

Environmental and cost efficiency of pesticide use in transgenic and conventional cotton production  

Microsoft Academic Search

This study focuses on the quantification of pesticide use efficiency for producers of transgenic cotton versus conventional cotton in order to test for the improvement promised by the genetically engineered crop. The environmental and cost efficiency of pesticide use is assessed by means of data envelopment analysis (DEA) and the external effects of pesticide are quantified by means of the

Ada Wossink; Zulal S. Denaux

2006-01-01

226

Production of a polyester degrading extracellular hydrolase from Thermomonospora fusca.  

PubMed

The production of a polyester-degrading hydrolase from the thermophilic actinomycete Thermomonospora fusca was investigated with regard to its potential technical application. Only in the presence of a polyester (random aliphatic-aromatic copolyester from 1,4-butanediol, terephthalic acid, and adipic acid with around 40-50 mol % terephthalic acid in the acid component), the excretion of the extracellular enzyme could be achieved with an optimized synthetic medium using pectin and NH(4)Cl as nitrogen source. Compared to complex media, a significantly higher specific activity at comparable volumetric yields could be obtained, thus reducing the expenditure for purification. The activity profile in the medium is controlled by a complex process involving (1) induction of enzyme excretion, (2) enzyme adsorption on the hydrophobic polyester surface, (3) inhibition of enzyme generation by monomers produced by polyester cleavage, and (4) enzyme denaturation. Diafiltration with cellulose acetate membranes as the sole downstream processing step led to a product of high purity and with sufficient yield (60% of total activity). Scaling-up from shaking flasks to a fermentor scale of 100 L revealed no specific problems. However, the excretion of the hydrolase by the actinomycete turned out to be inhibited by the degradation products (monomers) of the aliphatic-aromatic copolyester used as inductor for the enzyme production. The crude enzyme exhibited generally similar properties (temperature and pH optimum) as the highly purified hydrolase described previously; however, the storage capability and thermal stability is improved when the crude enzyme solution is diafiltrated. PMID:12363342

Gouda, Mona K; Kleeberg, Ilona; van den Heuvel, Joop; Müller, Rolf-Joachim; Deckwer, Wolf-Dieter

227

Degradation of ethylene thiourea (ETU) with three fenton treatment processes.  

PubMed

Anodic Fenton treatment (AFT), an electrochemical, hydroxyl radical oxidation treatment system, was developed for the degradation of aqueous pesticides and other aqueous organic wastes. AFT of ethylene thiourea (ETU) was optimized and compared with electrochemical Fenton treatment (EFT) and classic Fenton treatment (CFT). ETU is a known carcinogen and is an impurity and degradation product of the widely used ethylenebisdithiocarbamate (EBDC) fungicide group. ETU was degraded effectively in all treatment methods, with CFT being the most rapid; however, significant differences in degradation product profiles were noted over the course of treatments. AFT displayed the most efficient degradation of primary degradation products of ETU. PMID:11141275

Saltmiras, D A; Lemley, A T

2000-12-01

228

Photocatalytic transformation of pesticides in aqueous titanium dioxide suspensions using artificial and solar light: intermediates and degradation pathways  

Microsoft Academic Search

It has been shown that a wide range of organic compounds in aqueous solutions is photocatalytically oxidized to carbon dioxide in the presence of titanium dioxide with artificial and solar light. The photocatalytic mineralization of the most important classes of pesticides in water by illuminated TiO2 has been reviewed. The study focuses on the determination of the nature of the

Ioannis K. Konstantinou; Triantafyllos A. Albanis

2003-01-01

229

Safe apples for baby-food production: survey of pesticide treatment regimes leaving minimum residues.  

PubMed

A total of 19 pesticide preparations were used according to agricultural practice in six trials in apple orchards. Using gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS), premature Golden Delicious apples collected 64, 50, 36 days before harvest and mature fruit were examined for residues of active ingredients. No residues of triflumuron, triazamate, chlorpyrifos, etofenprox, fenoxycarb, kresoxim-methyl, cyprodinyl, difenoconazole or thiram were detected in the first sampling. Also, the levels of chlorpyrifos-methyl, penconazole, tebuconazole and tolylfluanid dropped during the pre-harvest interval. Detectable residues of pyridaben, thiacloprid, trifloxystrobin and tetraconazole in harvested fruits were below 0.01 mg kg(-1), which is the maximum concentration of residues acceptable by baby-food producers in any raw material. The only residues exceeding this concentration were captan and teflubenzuron. Based on the data, farmers can choose pesticides for optimal treatment of plants, while enabling growth of a safe crop suitable for baby-food production. PMID:17487602

Ticha, Jana; Hajslova, Jana; Kovalczuk, Tomas; Jech, Martin; Honzicek, Jiri; Kocourek, Vladimir; Lansky, Miroslav; Kloutvorova, Jana; Falta, Vladan

2007-06-01

230

Pesticides use by smallholder farmers in vegetable production in Northern Tanzania.  

PubMed Central

Small-scale farmers in Northern Tanzania grow vegetables that include tomatoes, cabbages and onions and use many types of pesticides to control pests and diseases that attack these crops. Based on the use of questionnaires and interviews that were conducted in Arumeru, Monduli, Karatu, and Moshi rural districts, this study investigates farmers’ practices on vegetable pest management using pesticides and related cost and health effects. The types of pesticides used by the farmers in the study areas were insecticides (59%), fungicides (29%) and herbicides (10%) with the remaining 2% being rodenticides. About a third of the farmers applied pesticides in mixtures. Up to 90% had a maximum of 3 pesticides in a mixture. In all cases there were no specific instructions either from the labels or extension workers regarding these tank mixtures. Fifty three percent of the farmers reported that the trend of pesticide use was increasing, while 33% was constant and 14% was decreasing. More than 50 percent of the respondents applied pesticides up to 5 times or more per cropping season depending on the crop. Insecticides and fungicides were routinely applied by 77% and 7%, respectively by these farmers. Sixty eight percent of farmers reported having felt sick after routine application of pesticides. Pesticide-related health symptoms that were associated with pesticides use included skin problems and neurological system disturbances (dizziness, headache). Sixty one percent of farmers reported spending no money on health due to pesticides. These results can be used to develop a tool to quantify the cost of pesticide use in pest management by small-scale vegetable farmers in Northern Tanzania and contribute to the reformation of pesticide policy for safe and effective use of pesticides.

Ngowi, A.V.F.; Mbise, T.J.; Ijani, A.S.M.; London, L.; Ajayi, O. C.

2007-01-01

231

Unusual surface degradation products grown on archaeological bronze artefacts  

NASA Astrophysics Data System (ADS)

Within the framework of the EFESTUS project funded by the European Commission a large number of Cu-based archaeological artefacts from the Mediterranean basin have been studied to investigate their chemical composition, metallurgical features and corrosion products nature (i.e. the patina). By means of the combined use of X-ray photoelectron spectroscopy (XPS), optical microscopy (OM), scanning electron microscopy with energy dispersive X-ray spectrometry (SEM-EDS) and X-ray diffraction (XRD) the bronze artefacts have been studied for the detailed identification of the corrosion products and their micro-chemical structure in order to achieve information about degradation agents and mechanisms. In the present work, some examples of unusual corrosion products formed on the objects during the long-term burial are presented and related to the peculiar local context revealing the strong interaction between the bronze artefact and the chemical components found in the archaeological site.

Mezzi, A.; de Caro, T.; Riccucci, C.; Faraldi, F.; Veroli, C.; Caschera, D.

2013-05-01

232

Degradation products of beclomethasone dipropionate in human plasma.  

PubMed

The anti-inflammatory glucocorticosteroid beclomethasone dipropionate was found previously to degrade in human plasma at 37 degrees C to yield beclomethasone 17-monopropionate, beclomethasone 21-monopropionate, and beclomethasone together with three unknown species, D-1, D-2, and D-3. In this paper, we report the isolation of D-2 and D-3 by preparative HPLC and the elucidation of their structures. Both products D-2 and D-3 exhibited UV bathochromic shifts relative to beclomethasone dipropionate of 9 nm. From the mass spectrometry and 1H-NMR data, it is concluded that D-2 and D-3 are formed from beclomethasone and beclomethasone 21-monopropionate, respectively, with the loss of hydrogen chloride and the formation of a 9,11-epoxide. Data for 1H-NMR methyl chemical shifts are used to show that the epoxide has the mechanistically more plausible 9beta,11beta configuration. Thus, D-2 is 9beta, 11beta-epoxy-16beta-methyl-1,4-pregnadiene-17alpha,21- diol-3, 20-dione, and D-3 is its corresponding 21-propanoate. The various enzyme-catalyzed and nonenzyme-catalyzed reactions involved in the degradation of beclomethasone dipropionate in human plasma are discussed. A degradation scheme is proposed. PMID:9456299

Foe, K; Cheung, H T; Tattam, B N; Brown, K F; Seale, J P

1998-02-01

233

Occurrence of Chlorothalonil, Its Transformation Products, and Selected Other Pesticides in Texas and Oklahoma Streams, 2003-2004  

USGS Publications Warehouse

The primary purpose of the study described in this report was to determine if the fungicide chlorothalonil (2,4,5,6-tetrachloroisophthalonitrile), three of its transformation products, or selected other pesticides are transported to surface water after use on peanuts or other crops in Texas and Oklahoma. The results summarized here are part of a larger study that includes data from sites in Alabama, Florida, and Georgia. Chlorothalonil is classified as a probable carcinogen, and the 4-hydroxy of chlorothalonil transformation product is more soluble, more stable, and, for some species, more toxic than its parent compound. In 2003, water samples were collected from three surface-water sites in Texas and two surface-water sites in Oklahoma; in 2004, samples were collected from the two Oklahoma sites. Chlorothalonil was not detected in any of the 20 samples analyzed. The 4-hydroxy of chlorothalonil transformation product was detected in three samples collected in 2004, with a maximum concentration of 0.018 microgram per liter (?g/L); the other two transformation products (diamide chlorothalonil and 1-amide-4-hydroxy chlorothalonil) were not detected in any sample. In addition, 19 samples were analyzed for as many as 109 other pesticides and transformation products. Atrazine was detected in 13 samples and had a maximum concentration of 0.122 ?g/L. Deethylatrazine was detected in 10 samples and had a maximum concentration of 0.04 ?g/L. Metolachlor was detected in eight samples and had a maximum concentration of 0.019 ?g/L. Fifteen other pesticides or pesticide transformation products also were detected. In general, concentrations of pesticides were less than concentrations that are commonly observed in Midwestern streams. The results indicate that the use of chlorothalonil on peanut crops has not resulted in substantial contamination of the studied streams in Texas and Oklahoma.

Battaglin, William A.; Kuivila, Kathryn; Winton, Kim; Meyer, Michael

2008-01-01

234

[A model study of pesticide biodegradation in soil].  

PubMed

This study addresses the efficiency of microbial preparations to degrade pesticide residues in soil. A method to degrade pesticides DNOC and pendimethalin using Pseudomonas and Arthrobacter bacteria with a fertilizer is described. PMID:17352205

Bieganska, J

235

Treatment of an aqueous pesticides mixture solution by direct and indirect electrochemical advanced oxidation processes  

Microsoft Academic Search

In the present work, a comparative study on the degradation of a mixture of three pesticides (chlortoluron, carbofuran and bentazon) has been carried out by electrochemical advanced oxidation processes such as anodic oxidation and electro-Fenton using boron-doped diamond (BDD) anode. These processes are based on the in situ production of hydroxyl radical, a highly strong oxidant, which allows the degradation

Aida Kesraoui Abdessalem; Mehmet A. Oturan; Nihal Oturan; Nizar Bellakhal; Mohamed Dachraoui

2010-01-01

236

Monitoring land degradation in Southern Africa based on net primary productivity  

Microsoft Academic Search

Land degradation involves conditions of reduced net primary production (NPP). Our objective was to develop and evaluate a land degradation monitoring approach that is based on NPP. NPP was modeled using the Global Production Efficiency Model (GLO-PEM) and 1km AVHRR data. Degraded areas in the Northern Province of South Africa were successfully detected using NPP, Rain Use Efficiency (RUE) and

K. J. Wessels; S. D. Prince; J. Small

2003-01-01

237

The role of degradant profiling in active pharmaceutical ingredients and drug products  

Microsoft Academic Search

Forced degradation studies are used to facilitate the development of analytical methodology, to gain a better understanding of active pharmaceutical ingredient (API) and drug product (DP) stability, and to provide information about degradation pathways and degradation products. In order to fulfill development and regulatory needs, this publication provides a roadmap for when and how to perform studies, helpful tools in

Karen M. Alsante; Akemi Ando; Roland Brown; Janice Ensing; Todd D. Hatajik; Wei Kong; Yoshiko Tsuda

2007-01-01

238

Degradation of selected pesticide active ingredients and commercial formulations in water by the photo-assisted Fenton reaction  

Microsoft Academic Search

The destruction of pesticide active ingredients (AI) and commercial formulations in acidic aqueous solution with the catalytic photo-Fenton, Fe(III)\\/H2O2\\/UV, advanced oxidation process has been studied. The AI are alachlor, aldicarb, atrazine, azinphos-methyl, captan, carbofuran, dicamba, disulfoton, glyphosate, malathion, methoxylchlor, metolachlor, picloram and simazine. Complete loss of pure AI occurred in most cases in <30min under the following conditions: 5.0×10?5M Fe(III),

Patrick L Huston; Joseph J Pignatello

1999-01-01

239

Protonation and Degradation Reactions of s-Triazine Herbicides  

Microsoft Academic Search

Desethyl atrazine and desethyl terbutylazine, the degradation products of two commonly encountered pesticides, were investigated by UV spectrophotometric and electrochemical techniques. In a sufficiently acidic environment, both compounds undergo further redox degradation which involves the cleavage of the chlorine atom. The reaction is pH dependent and proceeds via the protonated forms of both compounds. Spectrophotometric data indicate that the pH

M. P. Colombini; R. Fuoco; S. Giannarelli; L. Posp??šil; R. Trsková

1998-01-01

240

Variation in pesticide hazard from arable crop production in Great Britain from 1992 to 2002: Pesticide risk indices and policy analysis  

Microsoft Academic Search

Attempts to direct policy according to scientific findings are hampered by the multidimensionality of the potential impacts of pesticides which may affect consumers, operators, wildlife and the environment. Pesticide risk indices seek to reduce these multidimensional impacts to a single dimension and are increasingly used to understand variation in the hazard inherent in pesticides at the farm, regional and national

Paul Cross; Gareth Edwards-Jones

2006-01-01

241

Enzymatic Analysis of G- and V-Agents and Their Degradation Products.  

National Technical Information Service (NTIS)

We are presenting a rapid and highly reliable analytical methodology for nerve agents and their degradation products. The approach is to augment existing analytical methods with the specificity of the enzymatic degradation of the agents and their phosphon...

I. Elashvili

2003-01-01

242

Enhanced enzymatic cellulose degradation by cellobiohydrolases via product removal.  

PubMed

Product inhibition by cellobiose decreases the rate of enzymatic cellulose degradation. The optimal reaction conditions for two Emericella (Aspergillus) nidulans-derived cellobiohydrolases I and II produced in Pichia pastoris were identified as CBHI: 52 °C, pH 4.5-6.5, and CBHII: 46 °C, pH 4.8. The optimum in a mixture of the two was 50 °C, pH 4.9. An almost fourfold increase in enzymatic hydrolysis yield was achieved with intermittent product removal of cellobiose with membrane filtration (2 kDa cut-off): The conversion of cotton cellulose after 72 h was ~19 % by weight, whereas the conversion in the parallel batch reaction was only ~5 % by weight. Also, a synergistic effect, achieving ~27 % substrate conversion, was obtained by addition of endo-1,4-?-D-glucanase. The synergistic effect was only obtained with product removal. By using pure, monoactive enzymes, the work illustrates the profound gains achievable by intermittent product removal during cellulose hydrolysis. PMID:23076365

Gavlighi, Hassan Ahmadi; Meyer, Anne S; Mikkelsen, J Dalgaard

2012-10-18

243

Modeling Degradation Product Partitioning in Chlorinated-DNAPL Source Zones  

NASA Astrophysics Data System (ADS)

Metabolic reductive dechlorination degrades aqueous phase contaminant concentrations, increasing the driving force for DNAPL dissolution. Results from laboratory and field investigations suggest that accumulation of cis-dichloroethene (cis-DCE) and vinyl chloride (VC) may occur within DNAPL source zones. The lack of (or slow) degradation of cis-DCE and VC within bioactive DNAPL source zones may result in these dechlorination products becoming distributed among the solid, aqueous, and organic phases. Partitioning of cis-DCE and VC into the organic phase may reduce aqueous phase concentrations of these contaminants and result in the enrichment of these dechlorination products within the non-aqueous phase. Enrichment of degradation products within DNAPL may reduce some of the advantages associated with the application of bioremediation in DNAPL source zones. Thus, it is important to quantify how partitioning (between the aqueous and organic phases) influences the transport of cis-DCE and VC within bioactive DNAPL source zones. In this work, abiotic two-phase (PCE-water) one-dimensional column experiments are modeled using analytical and numerical methods to examine the rate of partitioning and the capacity of PCE-DNAPL to reversibly sequester cis-DCE. These models consider aqueous-phase, nonaqueous phase, and aqueous plus nonaqueous phase mass transfer resistance using linear driving force and spherical diffusion expressions. Model parameters are examined and compared for different experimental conditions to evaluate the mechanisms controlling partitioning. Biot number, a dimensionless number which is an index of the ratio of the aqueous phase mass transfer rate in boundary layer to the mass transfer rate within the NAPL, is used to characterize conditions in which either or both processes are controlling. Results show that application of a single aqueous resistance is capable to capture breakthrough curves when DNAPL is distributed in porous media as low-saturation ganglia, while diffusion within the DNAPL should be considered for larger NAPL pools. These results offer important insights to the monitoring and interpretation of bioremediation strategies employed within DNAPL source zones.

Boroumand, A.; Ramsburg, A.; Christ, J.; Abriola, L.

2009-12-01

244

Selectivity of pesticides used in integrated apple production to the lacewing, Chrysoperla externa.  

PubMed

This research aimed to assess the toxicity of the pesticides abamectin 18 CE (0.02 g a.i. L-1), carbaryl 480 SC (1.73 g a.i. L-1), sulfur 800 GrDA (4.8 g a.i. L-1), fenitrothion 500 CE (0.75 g a.i. L-1), methidathion 400 CE (0.4 g a.i. L-1), and trichlorfon 500 SC (1.5 g a.i. L-1) as applied in integrated apple production in Brazil on the survival, oviposition capacity, and egg viability of the lacewing, Chrysoperla externa (Hagen) (Neuroptera: Chrysopidae) from Bento Gonçalves and Vacaria, Rio Grande do Sul State, Brazil. An attempt was made to study morphological changes caused by some of these chemicals, by means of ultrastructural analysis, using a scanning electronic microscope. Carbaryl, fenitrothion, and methidathion caused 100% adult mortality for both populations, avoiding evaluation of pesticides' effects on predator reproductive parameters. Abamectin and sulfur also affected the survival of these individuals with mortality rates of 10% and 6.7%, respectively, for adults from Bento Gonçalves, and were harmless to those from Vacaria at the end of evaluation. Trichlorfon was also harmless to adults from both populations. No compound reduced oviposition capacity. C. externa from Vacaria presented higher reproductive potential than those from Bento Gonçalves. In relation to egg viability, sulfur was the most damaging compound to both populations of C. externa. Ultrastructural analyses showed morphological changes in the micropyle and the chorion of eggs laid by C. externa treated with either abamectin or sulfur. The treatment may have influenced the fertilization of C. externa eggs and embryonic development. Sulfur was responsible for malformations in the end region of the abdomen and genitals of treated females. When applied to adults, abamectin, sulfur, and trichlorfon were harmless, while carbaryl, fenitrothion, and methidathion were harmful, according to the IOBC classification. PMID:20879916

Moura, Alexandre Pinho; Carvalho, Geraldo Andrade; Moscardini, Valéria Fonseca; Lasmar, Olinto; Rezende, Denise Tourino; Marques, Márcio Candeias

2010-01-01

245

Selectivity of Pesticides used in Integrated Apple Production to the Lacewing, Chrysoperla externa  

PubMed Central

This research aimed to assess the toxicity of the pesticides abamectin 18 CE (0.02 g a.i. L-1), carbaryl 480 SC (1.73 g a.i. L-1), sulfur 800 GrDA (4.8 g a.i. L-1), fenitrothion 500 CE (0.75 g a.i. L-1), methidathion 400 CE (0.4 g a.i. L-1), and trichlorfon 500 SC (1.5 g a.i. L-1) as applied in integrated apple production in Brazil on the survival, oviposition capacity, and egg viability of the lacewing, Chrysoperla externa (Hagen) (Neuroptera: Chrysopidae) from Bento Gonçalves and Vacaria, Rio Grande do Sul State, Brazil. An attempt was made to study morphological changes caused by some of these chemicals, by means of ultrastructural analysis, using a scanning electronic microscope. Carbaryl, fenitrothion, and methidathion caused 100% adult mortality for both populations, avoiding evaluation of pesticides' effects on predator reproductive parameters. Abamectin and sulfur also affected the survival of these individuals with mortality rates of 10% and 6.7%, respectively, for adults from Bento Gonçalves, and were harmless to those from Vacaria at the end of evaluation. Trichlorfon was also harmless to adults from both populations. No compound reduced oviposition capacity. C. externa from Vacaria presented higher reproductive potential than those from Bento Gonçalves. In relation to egg viability, sulfur was the most damaging compound to both populations of C. externa. Ultrastructural analyses showed morphological changes in the micropyle and the chorion of eggs laid by C. externa treated with either abamectin or sulfur. The treatment may have influenced the fertilization of C. externa eggs and embryonic development. Sulfur was responsible for malformations in the end region of the abdomen and genitals of treated females. When applied to adults, abamectin, sulfur, and trichlorfon were harmless, while carbaryl, fenitrothion, and methidathion were harmful, according to the IOBC classification.

Moura, Alexandre Pinho; Carvalho, Geraldo Andrade; Moscardini, Valeria Fonseca; Lasmar, Olinto; Rezende, Denise Tourino; Marques, Marcio Candeias

2010-01-01

246

High Glucose Promotes A? Production by Inhibiting APP Degradation  

PubMed Central

Abnormal deposition of neuriticplaques is the uniqueneuropathological hallmark of Alzheimer’s disease (AD).Amyloid ? protein (A?), the major component of plaques, is generated from sequential cleavage of amyloid? precursor protein (APP) by ?-secretase and ?-secretase complex. Patients with diabetes mellitus (DM), characterized by chronic hyperglycemia,have increased risk of AD development.However, the role of high blood glucose in APP processing and A? generation remains elusive. In this study, we investigated the effect of high glucose on APP metabolism and A? generation in cultured human cells. We found that high glucose treatment significantly increased APP protein level in both neuronal-like and non-neuronal cells, and promoted A? generation. Furthermore, we found that high glucose-induced increase of APP level was not due to enhancement of APP gene transcription but resulted from inhibition of APP protein degradation. Taken together, our data indicated that hyperglycemia could promote AD pathogenesis by inhibiting APP degradation and enhancing A? production. More importantly, the elevation of APP level and A? generation by high glucose was caused by reduction of APP turnover rate.Thus,our study provides a molecular mechanism of increased risk of developing AD in patients withDMand suggests thatglycemic control might be potentially beneficial for reducing the incidence of AD in diabetic patients and delaying the AD progression.

Zhang, Shuting; Song, Weihong

2013-01-01

247

High glucose promotes A? production by inhibiting APP degradation.  

PubMed

Abnormal deposition of neuriticplaques is the uniqueneuropathological hallmark of Alzheimer's disease (AD).Amyloid ? protein (A?), the major component of plaques, is generated from sequential cleavage of amyloid? precursor protein (APP) by ?-secretase and ?-secretase complex. Patients with diabetes mellitus (DM), characterized by chronic hyperglycemia,have increased risk of AD development.However, the role of high blood glucose in APP processing and A? generation remains elusive. In this study, we investigated the effect of high glucose on APP metabolism and A? generation in cultured human cells. We found that high glucose treatment significantly increased APP protein level in both neuronal-like and non-neuronal cells, and promoted A? generation. Furthermore, we found that high glucose-induced increase of APP level was not due to enhancement of APP gene transcription but resulted from inhibition of APP protein degradation. Taken together, our data indicated that hyperglycemia could promote AD pathogenesis by inhibiting APP degradation and enhancing A? production. More importantly, the elevation of APP level and A? generation by high glucose was caused by reduction of APP turnover rate.Thus,our study provides a molecular mechanism of increased risk of developing AD in patients withDMand suggests thatglycemic control might be potentially beneficial for reducing the incidence of AD in diabetic patients and delaying the AD progression. PMID:23894546

Yang, Yi; Wu, Yili; Zhang, Shuting; Song, Weihong

2013-07-23

248

Enhancing the promiscuous phosphotriesterase activity of a thermostable lactonase (GkaP) for the efficient degradation of organophosphate pesticides.  

PubMed

The phosphotriesterase-like lactonase (PLL) enzymes in the amidohydrolase superfamily hydrolyze various lactones and exhibit latent phosphotriesterase activities. These enzymes serve as attractive templates for in vitro evolution of neurotoxic organophosphates (OPs) with hydrolytic capabilities that can be used as bioremediation tools. Here, a thermostable PLL from Geobacillus kaustophilus HTA426 (GkaP) was targeted for joint laboratory evolution with the aim of enhancing its catalytic efficiency against OP pesticides. By a combination of site saturation mutagenesis and whole-gene error-prone PCR approaches, several improved variants were isolated. The most active variant, 26A8C, accumulated eight amino acid substitutions and demonstrated a 232-fold improvement over the wild-type enzyme in reactivity (k(cat)/K(m)) for the OP pesticide ethyl-paraoxon. Concomitantly, this variant showed a 767-fold decrease in lactonase activity with ?-decanolactone, imparting a specificity switch of 1.8 × 10(5)-fold. 26A8C also exhibited high hydrolytic activities (19- to 497-fold) for several OP pesticides, including parathion, diazinon, and chlorpyrifos. Analysis of the mutagenesis sites on the GkaP structure revealed that most mutations are located in loop 8, which determines substrate specificity in the amidohydrolase superfamily. Molecular dynamics simulation shed light on why 26A8C lost its native lactonase activity and improved the promiscuous phosphotriesterase activity. These results permit us to obtain further insights into the divergent evolution of promiscuous enzymes and suggest that laboratory evolution of GkaP may lead to potential biological solutions for the efficient decontamination of neurotoxic OP compounds. PMID:22798358

Zhang, Yu; An, Jiao; Ye, Wei; Yang, Guangyu; Qian, Zhi-Gang; Chen, Hai-Feng; Cui, Li; Feng, Yan

2012-07-13

249

Human Health, Environmental, and Economic Effects of Pesticide Use in Potato Production in Ecuador  

Microsoft Academic Search

Despite a near 90% literacy rate, more that 70% of men and 80% of women did not understand the color coding on pesticide labels indicating toxicity. Farmers' minimal use of protective clothing during pesticide preparation (gloves 14%, masks 8%, eye protection 3%) and application (plastic back cover 38%, poncho 26%, protective pants 26%) led to high rates of skin contact

David Yanggen; Donald Cole; Charles Crissman; Steve Sherwood

250

Pesticide flow analysis to assess human exposure in greenhouse flower production in Colombia.  

PubMed

Human exposure assessment tools represent a means for understanding human exposure to pesticides in agricultural activities and managing possible health risks. This paper presents a pesticide flow analysis modeling approach developed to assess human exposure to pesticide use in greenhouse flower crops in Colombia, focusing on dermal and inhalation exposure. This approach is based on the material flow analysis methodology. The transfer coefficients were obtained using the whole body dosimetry method for dermal exposure and the button personal inhalable aerosol sampler for inhalation exposure, using the tracer uranine as a pesticide surrogate. The case study was a greenhouse rose farm in the Bogota Plateau in Colombia. The approach was applied to estimate the exposure to pesticides such as mancozeb, carbendazim, propamocarb hydrochloride, fosetyl, carboxin, thiram, dimethomorph and mandipropamide. We found dermal absorption estimations close to the AOEL reference values for the pesticides carbendazim, mancozeb, thiram and mandipropamide during the study period. In addition, high values of dermal exposure were found on the forearms, hands, chest and legs of study participants, indicating weaknesses in the overlapping areas of the personal protective equipment parts. These results show how the material flow analysis methodology can be applied in the field of human exposure for early recognition of the dispersion of pesticides and support the development of measures to improve operational safety during pesticide management. Furthermore, the model makes it possible to identify the status quo of the health risk faced by workers in the study area. PMID:23528812

Lesmes-Fabian, Camilo; Binder, Claudia R

2013-03-25

251

Pesticide Flow Analysis to Assess Human Exposure in Greenhouse Flower Production in Colombia  

PubMed Central

Human exposure assessment tools represent a means for understanding human exposure to pesticides in agricultural activities and managing possible health risks. This paper presents a pesticide flow analysis modeling approach developed to assess human exposure to pesticide use in greenhouse flower crops in Colombia, focusing on dermal and inhalation exposure. This approach is based on the material flow analysis methodology. The transfer coefficients were obtained using the whole body dosimetry method for dermal exposure and the button personal inhalable aerosol sampler for inhalation exposure, using the tracer uranine as a pesticide surrogate. The case study was a greenhouse rose farm in the Bogota Plateau in Colombia. The approach was applied to estimate the exposure to pesticides such as mancozeb, carbendazim, propamocarb hydrochloride, fosetyl, carboxin, thiram, dimethomorph and mandipropamide. We found dermal absorption estimations close to the AOEL reference values for the pesticides carbendazim, mancozeb, thiram and mandipropamide during the study period. In addition, high values of dermal exposure were found on the forearms, hands, chest and legs of study participants, indicating weaknesses in the overlapping areas of the personal protective equipment parts. These results show how the material flow analysis methodology can be applied in the field of human exposure for early recognition of the dispersion of pesticides and support the development of measures to improve operational safety during pesticide management. Furthermore, the model makes it possible to identify the status quo of the health risk faced by workers in the study area.

Lesmes-Fabian, Camilo; Binder, Claudia R.

2013-01-01

252

Enzymatic degradation of plutonium-contaminated cellulose products  

SciTech Connect

Enzyme solutions produced for commercial purposes unrelated to waste management have the potential for reducing the volume of wastes in streams containing cellulose, lipid and protein materials. For example, the authors have shown previously that cellulases used in denim production and in detergent formulations are able to digest cellulose-containing sorbents and other cellulose-based wastes contaminated either with crude oil or with uranium. This presentation describes the use of one such enzyme preparation (Rapidase{trademark}, manufactured by Genencor, Rochester, NY) for the degradation of cotton sorbents intentionally contaminated with low levels of plutonium. This is part of a feasibility study to determine if such treatments have a role in reducing the volume of low level and transuranic wastes to minimize the amount of radionuclide-contaminated waste destined for costly disposal options.

Heintz, C.E.; Rainwater, K.A.; Swift, L.M. [Texas Tech Univ., Lubbock, TX (United States); Barnes, D.L. [Amarillo National Resource Center for Plutonium, TX (United States); Worl, L.A. [Los Alamos National Lab., NM (United States)

1999-06-01

253

Enzymatic degradation of plutonium-contaminated cellulose products  

SciTech Connect

Enzyme solutions produced for commercial purposes unrelated to waste management have the potential for reducing the volume of wastes in streams containing cellulose, lipid and protein materials. For example, the authors have shown that cellulases used in denim production and in detergent formulations are able to digest cellulose-containing sorbents and other cellulose-based wastes contaminated either with crude oil or with radionuclides. This presentation describes the use of one such enzyme preparation (Rapidase{trademark}) for the degradation of cotton sorbents intentionally contaminated with low levels of plutonium. This is part of a feasibility study to determine if such treatments have a role in reducing the volume of low level and transuranic wastes to minimize the amount of radionuclide-contaminated waste that must be disposed of in secured storage areas.

Heintz, C.E.; Rainwater, K.A.; Swift, L.M. [Texas Tech Univ., Lubbock, TX (United States); Barnes, D.L. [Amarillo National Resource Center for Plutonium, TX (United States); Worl, L.; Avens, L. [Los Alamos National Lab., NM (United States)

1999-03-01

254

Effect of protein degradability on milk production of dairy ewes.  

PubMed

The objective of this experiment was to determine the effect of protein degradability of dairy sheep diets on milk yield and protein utilization across 2 levels of milk production. Three diets were formulated to provide similar energy concentrations and varying concentrations of rumen-degradable protein (RDP) and rumen-undegradable protein (RUP): 12% RDP and 4% RUP (12-4) included basal levels of RDP and RUP, 12% RDP and 6% RUP (12-6) included additional RUP, and 14% RDP and 4% RUP (14-4) included additional RDP. Diets were composed of alfalfa-timothy cubes, whole and ground corn, whole oats, dehulled soybean meal, and expeller soybean meal (SoyPlus, West Central, Ralston, IA). Estimates of RDP and RUP were based on the Small Ruminant Nutrition System model (2008) and feed and orts were analyzed for Cornell N fractions. Eighteen multiparous dairy ewes in midlactation were divided by milk yield (low and high) into 2 blocks of 9 ewes each and were randomly assigned within block (low and high) to 3 pens of 3 ewes each. Dietary treatments were arranged in a 3 x 3 Latin square within each block and applied to pens for 14-d periods. We hypothesized that pens consuming high-RUP diets (12-6) would produce more milk and milk protein than the basal diet (12-4) and pens consuming high-RDP diets (14-4) would not produce more milk than the basal diet (12-4). Ewes in the high-milk-yield square consumed more dry matter and produced more milk, milk fat, and milk protein than ewes in the low-milk-yield square. There was no effect of dietary treatment on dry matter intake. Across both levels of milk production, the 12-6 diet increased milk yield by 14%, increased milk fat yield by 14%, and increased milk protein yield by 13% compared with the 14-4 and 12-4 diets. Gross N efficiency (milk protein N/intake protein N) was 11 and 15% greater in the 12-6 and 12-4 diets, respectively, compared with the 14-4 diet. Milk urea N concentration was greater in the 12-6 diet and tended to be greater in the 14-4 diet compared with the 12-4 diet, indicating that the excretion of urea N in this study was more closely related to dietary crude protein concentration than to protein degradability. PMID:19700712

Mikolayunas-Sandrock, C; Armentano, L E; Thomas, D L; Berger, Y M

2009-09-01

255

Production of degradable polymers from food-waste streams  

SciTech Connect

In the United States, billions of pounds of cheese whey permeate and approximately 10 billion pounds of potatoes processed each year are typically discarded or sold as cattle feed at $3{endash}6/ton; moreover, the transportation required for these means of disposal can be expensive. As a potential solution to this economic and environmental problem, Argonne National Laboratory is developing technology that: Biologically converts existing food-processing waste streams into lactic acid and uses lactic acid for making environmentally safe, degradable polylactic acid (PLA) and modified PLA plastics and coatings. An Argonne process for biologically converting high-carbohydrate food waste will not only help to solve a waste problem for the food industry, but will also save energy and be economically attractive. Although the initial substrate for Argonne's process development is potato by-product, the process can be adapted to convert other food wastes, as well as corn starch, to lactic acid. Proprietary technology for biologically converting greater than 90% of the starch in potato wastes to glucose has been developed. Glucose and other products of starch hydrolysis are subsequently fermented by bacteria that produce lactic acid. The lactic acid is recovered, concentrated, and further purified to a polymer-grade product.

Tsai, S.P.: Coleman, R.D.; Bonsignore, P.V.; Moon, S.H.

1992-01-01

256

Production of degradable polymers from food-waste streams  

SciTech Connect

In the United States, billions of pounds of cheese whey permeate and approximately 10 billion pounds of potatoes processed each year are typically discarded or sold as cattle feed at $3{endash}6/ton; moreover, the transportation required for these means of disposal can be expensive. As a potential solution to this economic and environmental problem, Argonne National Laboratory is developing technology that: Biologically converts existing food-processing waste streams into lactic acid and uses lactic acid for making environmentally safe, degradable polylactic acid (PLA) and modified PLA plastics and coatings. An Argonne process for biologically converting high-carbohydrate food waste will not only help to solve a waste problem for the food industry, but will also save energy and be economically attractive. Although the initial substrate for Argonne`s process development is potato by-product, the process can be adapted to convert other food wastes, as well as corn starch, to lactic acid. Proprietary technology for biologically converting greater than 90% of the starch in potato wastes to glucose has been developed. Glucose and other products of starch hydrolysis are subsequently fermented by bacteria that produce lactic acid. The lactic acid is recovered, concentrated, and further purified to a polymer-grade product.

Tsai, S.P.: Coleman, R.D.; Bonsignore, P.V.; Moon, S.H.

1992-07-01

257

Gas-liquid chromatographic determination of nonpolar organochlorine pesticide residues in a crude vegetable oil and its refinery by-products.  

PubMed

A crude soybean oil, several of its refinery by-products (described as soapstock, deodorizer distillate, and clabber stock), and the completely refined oil were analyzed for pesticide residues. Fourteen organo-chlorine pesticides and pesticide metabolites were found in the deodorizer distillate; 5 of these were also found in the clabber stock. Levels in these by-products ranged from 0.3 to 8 ppm. Only endrin and dieldrin were detected in the crude oil at levels of 0.01 and 0.05 ppm, respectively. Forty to 150 times these levels were found in the deodorizer distillate and clabber stock. Pesticide residues were not detected in the refined oil or in the soapstock at limits of detection for dieldrin of about 0.01 and 0.1 ppm, respectively. The method used by the Food and Drug Administration to analyze fats and oils for multiple organohalogen pesticide residues was inadequate for the extraction of pesticide residues from vegetable oil refinery by-products. The method used to analyze the crude vegetable oil and the refinery by-products involved dissolution of the oil samples in ethyl acetate-toluene, filtration if necessary, cleanup by gel permeation chromatography, and then Florisil column chromatography. The oil was isolated from aqueous-oil mixtures by extraction with hexane before analysis. The crude soybean oil was fortified with 12 organohalogen pesticides and Aroclor 1254 at levels of 0.5-3.7 ppm. Recoveries ranged from 83 to 102%. PMID:6889594

Young, S J; Kamps, L R

1982-07-01

258

Determination of pharmaceuticals, personal care products, and pesticides in surface and treated waters: method development and survey.  

PubMed

Water is fundamental to the existence of life since it is essential to a series of activities, such as agriculture, power generation, and public and industrial supplies. The residual water generated by these activities is released into the environment, reaches the water systems, and becomes a potential risk to nontarget organisms. This paper reports the development and validation of a quantitative method, based on solid-phase extraction and liquid chromatography tandem mass spectrometry, for the simultaneous analysis of 18 pharmaceuticals and personal care products (PPCPs) and 33 pesticides in surface and drinking waters. The accuracy of the method was determined by calculating the recoveries, which ranged from 70 to 120 % for most pesticides and PPCPs, whereas limits of quantification ranged from 0.8 to 40 ng/L. After the validation step, the method was applied to drinking and surface waters. Pesticides and PPCPs were found in concentrations lower than 135.5 ng/L. The evaluation of different water sources with regard to contamination by pesticides and PPCPs has been quite poor in southern Brazil. PMID:23539208

Caldas, Sergiane Souza; Bolzan, Cátia Marian; Guilherme, Juliana Rocha; Silveira, Maria Angelis Kisner; Escarrone, Ana Laura Venquiaruti; Primel, Ednei Gilberto

2013-03-29

259

Relationship between bacterial diversity and function under biotic control: the soil pesticide degraders as a case study  

Microsoft Academic Search

In soil, the way biotic parameters impact the relationship between bacterial diversity and function is still unknown. To understand these interactions better, we used RNA-based stable-isotope probing to study the diversity of active atrazine-degrading bacteria in relation to atrazine degradation and to explore the impact of earthworm-soil engineering with respect to this relationship. Bulk soil, burrow linings and earthworm casts

Cécile Monard; Philippe Vandenkoornhuyse; Barbara Le Bot; Françoise Binet

2011-01-01

260

Pulmonary effects of acute exposure to degradation products of sulphur hexafluoride during electrical cable repair work  

Microsoft Academic Search

Six electrical workers accidentally exposed to degradation products of sulphur hexafluoride (SF6) during electrical repair work were followed up for one year. One degradation product, sulphur tetrafluoride (SF4), was identified from worksite measurements. Unprotected exposure in an underground enclosed space occurred for six hours over a 12 hour period. Initial symptoms included shortness of breath, chest tightness, productive cough, nose

A Kraut; R Lilis

1990-01-01

261

New methodology for estimating rumen protein degradation using the in vitro gas production technique  

Microsoft Academic Search

This paper explores the possibility of estimating in vitro degradable crude protein (IVDP) and effective crude protein (CP) degradation (EPD) of protein feeds in the rumen using a new method based on the in vitro gas production (GP) technique of Raab et al. [Raab, L., Cafantaris, B., Jilg, T., Menke, K.H., 1983. Rumen protein degradation and biosynthesis. 1. A new

L. Karlsson; M. Hetta; P. Udén; K. Martinsson

2009-01-01

262

Levels of organochlorine pesticides in crops and related products from Vojvodina, Serbia: estimated dietary intake.  

PubMed

Levels of 16 organochlorine pesticides (OCPs) were investigated in 39 composite samples of agricultural crops, related by-products, and foodstuffs collected in Vojvodina, Serbia, in 2002 through 2004. After extraction and cleanup, OCPs were determined by capillary gas chromatography using electron-capture detection. The highest mean level of 0.971 ng/g whole weight (ww) was found for alpha-HCH in wheat flour samples. OCPs levels were well lower than the respective maximum residue limits set by current European and Serbian regulations. Mean OCP levels were low (<1 ng/g ww) for all sample types. The most frequently determined residue was 4,4'-DDT (identified in 76.9% of all samples analyzed), followed by gamma-HCH (66.7%), beta-HCH (48.7%), and endosulfan II (41.0%). OCP levels were compared with data from other international surveys. Calculated daily intakes of OCPs by way of consumption of the crop products included in this study according to data of the Serbian National Institute for Statistics were compared with the acceptable daily intakes established by the Food and Agriculture Organization/World Health Organization. The average level of contamination of the Vojvodina diet was believed to be harmless regarding the studied food commodities. PMID:18197356

Skrbi?, B; Predojevi?, Z

2008-05-01

263

Comparative ecological risks of pesticides used in plantation production of papaya: application of the SYNOPS indicator.  

PubMed

Pesticides are used intensively for crop protection in tropical fruit plantations. Assessments of the relative risks posed by pesticides are needed to assist in the development of management plans that minimize ecological impacts. In this study, the risk indicator SYNOPS_2 was used to compare risks to aquatic ecosystems by pesticides commonly used in papaya plantations. Plant interception and spray drift were measured during six applications of three pesticides (chlorothalonil, chloropyrifos, and malathion) using a turbo fan driven sprayer. Plant interception was estimated to be higher (42.6+/-12.7%; p=0.04) in late (8-14 months old) than in early (4 months old) trees (20.1+/-25.3%). Chlorothalonil concentrations of up to 11.0 microg L(-1) were found in water from an adjacent ditch after field application. Concentrations of this pesticide (7.4+/-4.1 microg L(-1)) in runoff water were also significantly (p<0.01) higher than those of malathion (2.4+/-1.9 microg L(-1)) and chlorpyrifos (0.8+/-0.5 microg L(-1)). Good correlation between measured and predicted values (r2=0.56-0.85, p<0.01) showed that SYNOPS_2 is able to describe trends in runoff pollution in papaya plantations. Linear equations were obtained in order to correct numerical disagreement between measured and calculated runoff concentrations. An independent test showed a reasonable agreement between measured chlorothalonil concentrations and the predicted values using the proposed equations. Fifteen pesticides used in papaya cultivation were ranked according to their calculated chronic biological risk index. Pesticides with the highest risk index for non-target organisms were: chlorothalonil for algae, lambda cyahalotrin for Daphnia and fish, and malathion for earthworms. Chlorothalonil was the pesticide with the highest exposure level in water and therefore represents a high risk for aquatic life. Results show that SYNOPS_2 can be used as a pesticide risk indicator on papaya and possibly other tropical fruit plantations. PMID:17482661

Hernández-Hernández, Carlos N A; Valle-Mora, Javier; Santiesteban-Hernández, Antonio; Bello-Mendoza, Ricardo

2007-05-07

264

Toxicity of fipronil and its degradation products to Procambarus sp.: field and laboratory studies.  

PubMed

Fipronil is a phenylpyrazole insecticide that is the active ingredient in the pesticide Icon 6.2 FS which is applied to rice seeds targeting the rice water weevil. An arthropod-selective insecticide, fipronil blocks the GABA-gated chloride channel and is unique in that several of its degradation products have been indicated to be equal or more potent than fipronil. After application of rice seeds (2-3 days postplant) to flooded rice fields, water is typically pumped from the rice fields and can be used for the culture of crayfish (Procambarus sp.). Because fipronil is selective for arthropods, is transported via organic sediment, and crayfish consume organic sediment, 96-h LC(50) experiments were conducted with fipronil and three of its environmental derivatives in crayfish under conditions without carrier solvents in water of similar pH, alkalinity, and hardness as observed in south Louisiana crayfish culture ponds. Measured LC(50)s for fipronil to red swamp (Procambarus clarkii) and white river (Procambarus zonangulus) crayfish were 14.3 (95% CI; 5.1-23.4) and 19.5 (95% CI; 11.1-27.9) microg/L, respectively. LC(50)s of fipronil sulfone (11.2; 9.2-13.2 microg/L), fipronil sulfide (15.5; 13-18 microg/L); and the photoproduct, desulfinyl fipronil (68.6; 46-95.2 microg/L) displayed very high toxicity in crayfish. In situ toxicity studies using caged crayfish in culturing ponds receiving effluent from drained rice fields indicated that effluent from rice fields planted with Icon-treated seed was significantly more toxic compared to untreated surface water (40% survival compared to 83% survival). Hazard quotient comparisons using measured water concentrations in the field and laboratory-based LC(50)s indicated that fipronil and its metabolites in water resulting from Icon-treated rice seed planting poses a significant risk to crayfish survival. PMID:11503069

Schlenk, D; Huggett, D B; Allgood, J; Bennett, E; Rimoldi, J; Beeler, A B; Block, D; Holder, A W; Hovinga, R; Bedient, P

2001-10-01

265

Pesticides and oncogenic modulation.  

PubMed

Pesticides constitute a diverse class of chemicals used for the protection of agricultural products. Several lines of evidence demonstrate that organochlorine and organophosphate pesticides can cause malignant transformation of cells in in vitro and in vivo models. In the current minireview a comprehensive summary of recent in vitro findings is presented along with data reported from human population studies, regarding the impact of pesticide exposure on activation or dysregulation of oncogenes and tumor suppressor genes. Substantial mechanistic work suggests that pesticides are capable of inducing mutations in oncogenes and increase their transcriptional expression in vitro, whereas human population studies indicate associations between pesticide exposure levels and mutation occurrence in cancer-related genes. Further work is required to fully explore the exact mechanisms by which pesticide exposure affects the integrity and normal function of oncogenes and tumor suppressor genes in human populations. PMID:23354457

Vakonaki, Elena; Androutsopoulos, Vasilis P; Liesivuori, Jyrki; Tsatsakis, Aristidis M; Spandidos, Demetrios A

2013-01-24

266

Pretreatment of Refractory and Cyanide-Containing Pesticide Wastewater Using Sodium Hypochlorite  

Microsoft Academic Search

The cyanide-containing wastewater mainly derives from chemical Engineering industry such as pesticide production, electroplating and metallurgy. It is very important to treat this kind of wastewater, because of the redundant toxic contaminants it contains.In this paper,using refractory and cyanide-containing pesticide wastewater as the subject investigated the effect of sodium hypochlorite to its pretreatment. The results show that sodium hypochlorite degradation

Zhou Li; Lin Hai; Fu Kaibin; Yu Lulu; Wang Xiu; Tan Yuansi

2010-01-01

267

Effects of lindane on lindane-degrading Azotobacter chroococcum; evaluation of toxicity of possible degradation product(s) on plant and insect.  

PubMed

The effects of lindane on growth and plant growth-promoting traits of two lindane-degrading Azotobacter chroococcum strains (JL 15 and JL 104) were determined. The potential of both A. chroococcum strains to degrade lindane was also determined. Lower concentrations of lindane had a stimulatory effect, and higher concentrations generally had an inhibitory effect on growth and plant growth-promoting activities. A high percentage (>90%) of lindane was degraded by both strains at a lindane concentration of 10 ppm. Lindane at 1,000 ppm decreased seed germination and reduced seedling fresh weight. However, the possible degradation products for a starting lindane concentration of 10 ppm was found to be non-phytotoxic. Toxicity studies with larvae of Spilarctia obliqua resulted in an LC50 estimate of 3.41 ppm for lindane solutions into which leaf discs were dipped. No toxicity was observed for possible degradation products. PMID:23262986

Paul, Sangeeta; Paul, Bishwajeet; Aslam Khan, Md; Aggarwal, Chetana; Thakur, Jyoti K; Rathi, Maheshwar S

2012-12-22

268

Sensitivity analyses for four pesticide leaching models.  

PubMed

Sensitivity analyses using a one-at-a-time approach were carried out for leaching models which have been widely used for pesticide registration in Europe (PELMO, PRZM, PESTLA and MACRO). Four scenarios were considered for simulation of the leaching of two theoretical pesticides in a sandy loam and a clay loam soil, each with a broad distribution across Europe. Input parameters were varied within bounds reflecting their uncertainty and the influence of these variations on model predictions was investigated for accumulated percolation at 1-m depth and pesticide loading in leachate. Predictions for the base-case scenarios differed between chromatographic models and the preferential flow model MACRO for which large but transient pesticide losses were predicted in the clay loam. Volumes of percolated water predicted by the four models were affected by a small number of input parameters and to a small extent only, suggesting that meteorological variables will be the main drivers of water balance predictions. In contrast to percolation, predictions for pesticide loss were found to be sensitive to a large number of input parameters and to a much greater extent. Parameters which had the largest influence on the prediction of pesticide loss were generally those related to chemical sorption (Freundlich exponent nf and distribution coefficient Kf) and degradation (either degradation rates or DT50, QTEN value). Nevertheless, a significant influence of soil properties (field capacity, bulk density or parameters defining the boundary between flow domains in MACRO) was also noted in at least one scenario for all models. Large sensitivities were reported for all models, especially PELMO and PRZM, and sensitivity was greater where only limited leaching was simulated. Uncertainty should be addressed in risk assessment procedures for crop-protection products. PMID:12974348

Dubus, Igor G; Brown, Colin D; Beulke, Sabine

2003-09-01

269

Detection of pesticides and pesticide metabolites using the cross reactivity of enzyme immunoassays.  

PubMed

Enzyme immunoassay is an important environmental analysis method that may be used to identify many pesticide analytes in water samples. Because of similarities in chemical structure between various members of a pesticide class, there often may be an unwanted response that is characterized by a percentage of cross reactivity. Also, there may be cross reactivity caused by degradation products of the target analyte that may be present in the sample. In this paper, the concept of cross reactivity caused by degradation products or by nontarget analytes is explored as a tool for identification of metabolites or structurally similar compounds not previously known to be present in water samples. Two examples are examined in this paper from various water quality studies. They are alachlor and its metabolite, alachlor ethane sulfonic acid, and atrazine and its class members, prometryn and propazine. A method for using cross reactivity for the detection of these compounds is explained in this paper. PMID:11234804

Thurman, E M; Aga, D S

270

Pesticide\\/Environmental Exposures and Parkinson's Disease in East Texas  

Microsoft Academic Search

Epidemiological evidence suggests that pesticides and other environmental exposures may have a role in the etiology of idiopathic Parkinson's disease (PD). However, there is little human data on risk associated with specific pesticide products, including organic pesticides such as rotenone with PD. Using a case-control design, this study examined self-reports of exposure to pesticide products, organic pesticides such as rotenone,

Amanpreet S. Dhillon; G. Lester Tarbutton; Jeffrey L. Levin; George M. Plotkin; Larry K. Lowry; J. Torey Nalbone; Sara Shepherd

2008-01-01

271

RESISTANCE TO PESTICIDES  

Technology Transfer Automated Retrieval System (TEKTRAN)

The occurrence of pesticide resistance stands as one of the most chronic and formidable problems for crop production and public health worldwide. The evolution of different resistance mechanisms by pestiferous organisms has diminished the lethal action of pesticides and led to greater difficulties ...

272

PR notice 87-1. Notice to manufacturers, formulators, producers and registrants of pesticide products  

SciTech Connect

The notice describes the label improvement program for pesticides registered under Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) and applied through irrigation systems (also known as chemigation). The notice explains the program, defines who and what the notice applies to, and details about how the labeling is to be done. These label changes are necessary to prevent unnecessary human or animal exposure to the pesticide.

Not Available

1987-03-01

273

Effects of pesticides on songbird productivity in conjunction with pecan cultivation in southern Georgia: A multiple-exposure experimental design  

USGS Publications Warehouse

A prototypic experimental design was used to assess sublethal effects of multiple and varied organophosphates and carbamates on reproduction in birds. The design allowed for classification of pesticide exposure according to toxicity of applied compounds and type and frequency of applications. Daily survival rates (DSRs) of nests, eggs, and nestlings were determined for northern mockingbirds (Mimus polyglottos), brown thrashers (Toxostoma rufum), and northern cardinals (Cardinalis cardinalis) nesting along edges of pecan orchards and row crops in southern Georgia [USA]. Egg and nestling DSRs for all species combined varied inversely (P 0.05) among three exposure levels. Brain cholinesterase activities were age-dependent and substantiated adult, but not nestling, exposure. Results suggest that increasing exposure to pesticides may reduce songbird productivity.

Patnode, K.A.; White, D.H.

1991-01-01

274

The influence of albumin degradation products on central action of amphetamine and pentetrazol.  

PubMed

Trypsin degradation products of albumin given intraperitoneally and into the brain ventricle decrease psychostimulatory effects of amphetamine as evaluated by Lat's test and stereotypy. Albumin degradation products obtained by trypsin and leukocyte digestion increased the convulsant effects of pentetrazol. These effects are possibly connected with a neurohormonal background in the central nervous system. PMID:999469

Sobaniec, W; Moniuszko-Jakoniuk, J; Zarebski, M; Buczko, W; Tarasiewicz, S

1976-01-01

275

Intensification of Microbial Degradation of Crude Oil and Oil Products in the Presence of Perfluorodecalin  

Microsoft Academic Search

The possibility of using perfluorinated organic compounds for growing microorganisms and degrading xenobiotics has been demonstrated for the first time with perfluorodecalin (PFD), a gas-transporting component of the blood substitute Perftoran. This is particularly promising for intensifying microbial degradation of oil and oil products and the production of biodegrader biomass in synthetic mineral media. The addition of PFD to a

M. K. Bakulin; V. Yu. Zakharov; E. V. Chebotarev

2004-01-01

276

The global loss of net primary production resulting from human-induced soil degradation in drylands  

Microsoft Academic Search

Land degradation, the temporary or permanent reduction of land's productive capacity resulting from poor land management, has gained considerable attention as an environmental and development issue of global importance, in particular in the Earth's drylands. This study presents a global estimate of net primary production (NPP) losses caused by human-induced dryland degradation. Due to the large uncertainties related to international

Michael Zika; Karl-Heinz Erb

2009-01-01

277

The quantitative determination of aspirin and its degradation products in a model solution aerosol  

Microsoft Academic Search

Formulation of pressurized aerosol solutions in propellants for inhalation requires the use of high quantities of surfactants to solubilize the drug. Due to the lipophilic nature of these surfactants, analytical difficulties are created for those wishing to quantify the drug and its degradation products. In order to quantify drug and degradation products by LC it is necessary to separate surfactant

Frank E. Blondino; Peter R. Byron

1995-01-01

278

[Dietary risk assessment for pesticide residues in food of plant origin during the plant protection product's registration process].  

PubMed

One of the main goals of risk assessment during registration of plant protection product is to approve (or not) the proposed Maximum Residue Levels (MRLs) derived from the field trials conducted under Good Agricultural Practice (GAP). Generally, risk assessment at this stage is based on comparison of potential long- and short-term dietary intake of given pesticide with two earlier established outputs of hazard characterisation, i.e. Acceptable Daily Intake - ADI and Acute Reference Dose--ARfD. The first estimate of long-term hazard, which overestimates the risk, is comparing the Theoretical Maximum Daily Intake (TMDI) to the ADI of the pesticide. TMDI is based on assumption that all food products consumed over the lifetime of the consumer contain residues at level of MRL. Afterwards, the ADI is compared against International/National Estimated Daily Intake (IEDI/NEDI). I(N)EDI values provide a "best estimate" of dietary intake as they take into account residues in edible portions at level of median residue values from supervised trials. In case of short-term dietary exposure to acute toxic pesticides, the intake is compared to ARfD. The calculation of International/National Estimated Short-Term Intake IESTI/NESTI) requires single-day consumption data for the 97.5th percentile for each subgroups of consumers (so called "large portions") together with typical unit weight, and percentage of edible portion for each commodity as well as high, and median residue levels derived from the field trials. Additionally, in intake calculations for commodities with unit weight over 25 g, the variability factor (from 3 to 10) has been introduced, which reflects the possible high deposition of a pesticide on the individual unit, even when the quantified residue level in composite sample is relatively low. PMID:17713193

Struci?ski, Pawe?; Góralczyk, Katarzyna; Czaja, Katarzyna; Hernik, Agnieszka; Korcz, Wojciech; Ludwicki, Jan K

2006-01-01

279

Gamma radiolytic degradation of fluoranthene and monitoring of radiolytic products using GC MS and HPLC  

NASA Astrophysics Data System (ADS)

Removal of priority pollutant fluoranthene in methanol by gamma-irradiation under varied conditions has been optimized. The influence of applied dose and dose rate on the degradation of fluoranthene under nitrogen has been investigated. The preliminary radiolytic degradation efficiency has been monitored by spectrophotometry. HPLC and GC MS have been used to study the nature of degradation pattern. It is found that four main degradation products are formed and detected by HPLC. Different reversed phase columns have been used for the separation of degraded products under optimum chromatographic conditions. For 2 kGy dose ?80% fluoranthene has been degraded at dose rate 200 Gy/h. However, a dose of 370 Gy/h was more effective and it produces for less degradation products. Radiolytic degraded fluoranthene was also analyzed to detect various degradation products using GC MS. It was proposed that major products were hydrocarbons and methoxy group containing organic compounds after comparing their mass spectra with the installed NIST mass spectral library.

Bilal Butt, S.; Qureshi, Rashid Nazir

2008-06-01

280

Degradation process of grease due to SF/sub 6/ gas dissociation products  

SciTech Connect

It is known that some insulating materials are degraded due to dissociation products of SF/sub 6/ gas. Many studies related to the degradation of insulating materials have been accomplished. But no studies related to sealing materials, for instance (lubricating) grease and rubber have been made. This paper presents the degradation process of grease as follows. Properties of Lithium grease easily change in SF/sub 6/ gas including dissociation products owing to the degradation of Lithium soap used as thickner of grease. However, in the case of Bentonite grease and Urea grease, any changes of properties are not observed.

Suzuki, T.; Koyama, A.; Tomimuro, S.; Yoshiba, H.

1982-08-01

281

The role of purine degradation in methane biosynthesis and energy production in Methanococcus vannielii  

SciTech Connect

Research continues on the role of purine degradation in methane biosynthesis and energy production in Methanococcus vannielii. This report summarizes current progress of the research. Topics include: A survey of other methanogens for the purine degradation pathway; isolate and characterize the enzyme and products of formiminoglycine cleavage; ascertain the fate of glycine from the formiminoglycine cleavage; elucidate the route of incorporation of the formyl moiety of formiminoglycine into methane biosynthesis; determine the percent methane and amino acid synthesis from purine degradation; and related studies on xanthine dehydrogenase and pyrimidine degradation of M. Vannielii. (SM)

DeMoll, E.

1990-10-22

282

Hyaluronic acid degradation products induce neovascularization and fibroplasia in fetal rabbit wounds.  

PubMed

Scarless fetal wound healing occurs with mild fibroplasia and neovascularization, while the wound is persistently enriched with hyaluronic acid. Conversely, adult wounds are characterized by prominent fibroplasia, neovascularization, and scar formation, and hyaluronic acid is a transient component of the early adult wound matrix. Our group has reported that enzymatic degradation of fetal rabbit wound hyaluronic acid results in marked increases in fibroplasia, collagen deposition, and neovascularization. This altered, adultlike healing response is hypothesized to have resulted from the generation of biologically active hyaluronic acid degradation products. Therefore, this study analyzes the fibrovascular inductive activity of hyaluronic acid degradation products. Fetal rabbit wounds were treated with hyaluronic acid degradation products generated by methods known to produce oligosaccharides with significant angiogenic activity. Implants from wounds treated with either of the control solutions (n = 4 for each control) had identical histologic features characterized by a mild mononuclear cell infiltrate but neither infiltrating fibroblasts nor collagen. In marked contrast, implants from wounds treated with hyaluronic acid degradation products contained infiltrating fibroblasts and collagen intermixed with numerous blood vessels. Quantitation of capillary ingrowth showed a sixfold increase in the neovascular response in wounds treated with hyaluronic acid degradation products compared with either controls (p < 0.05). This study shows that hyaluronic acid degradation products stimulate neovascularization and fibroplasia in fetal wounds. These observations suggest that a balance between hyaluronic acid accumulation and degradation has significant regulatory influence in fetal tissue repair. PMID:17168864

Mast, B A; Frantz, F W; Diegelmann, R F; Krummel, T M; Cohen, I K

283

Evaluation of serum pesticide residue levels and liver function in persons exposed to dairy products contaminated with heptachlor  

SciTech Connect

The authors studied a group of 45 dairy farm family members who had consumed undiluted raw milk products known to be contaminated with residues of the pesticide heptachlor at concentrations as high as 89.2 ppm (fat basis). They compared results of serum pesticide assays for these exposed persons with results for an unexposed group of 94 persons from the same geographic area and the results from the Second National Health and Nutrition Examination Survey. The exposed group had significantly higher mean levels of primary heptachlor metabolites-i.e., heptachlor epoxide and oxychlordane than the unexposed group. In the exposed group, 21.2% had evaluated serum concentrations of these same metabolites; this rate was significantly greater than the rates in both the unexposed farm family members (heptachlor epoxide, 3.8%; oxychlordane, 6.3%) and the Second National Health and Nutrition Examination Survey sample (2.5% for both metabolites). However they found no evidence of related acute and/or subacute hepatic effects in these exposed persons regardless of their serum concentrations of pesticide residues.

Stehr-Green, P.A.; Wohlleb, J.C.; Royce, W.; Head, S.L.

1988-01-15

284

Chemoattractant activity of degradation products of fetal and adult skin extracellular matrix for keratinocyte progenitor cells  

PubMed Central

Biologic scaffolds composed of naturally occurring extracellular matrix (ECM) have been utilized as templates for the constructive remodeling of numerous tissues in preclinical studies and human clinical applications. The mechanisms by which ECM induces constructive remodeling are not well understood, but it appears that the degradation products of ECM scaffolds may play key roles in cell recruitment and constructive remodeling. The objective of the present study was to investigate the effects of age and species of the tissue from which ECM is harvested on the chemoattractant activity of degradation products of ECM for human keratinocyte stem and progenitor cells. Adult human skin ECM, fetal human skin ECM, and adult porcine skin ECM were prepared, enzymatically digested, characterized by SDS-PAGE, and evaluated for in vitro chemoattractant activity for human keratinocyte progenitor and stem cells (HEKn). Degradation products of human fetal skin ECM showed greater chemoattractant activity than human adult skin ECM degradation products for the HEKn. Degradation products of porcine adult skin ECM showed greater chemoattractant activity than human adult skin ECM. The human fetal skin ECM degradation products showed the strongest chemoattractant activity for the HEKn. The findings of this study support the concept that the mechanism of ECM scaffold remodeling involves the recruitment of lineage-directed progenitor cells by scaffold degradation products and that both the age and species of the tissue from which the ECM is harvested have an effect upon this chemoattractant potential.

Brennan, Ellen P.; Tang, Xiao-Han; Stewart-Akers, Ann M.; Gudas, Lorraine J.; Badylak, Stephen F.

2009-01-01

285

Biological Degradation of Common Pharmaceuticals and Personal Care Products in Soils with High Water Content  

Microsoft Academic Search

Biological degradation rates of six pharmaceuticals and personal care products were examined in soil from a land application\\u000a site and in adjacent soil with no prior history of effluent exposure. Microbial degradation rates were compared over 2 weeks\\u000a under standing water or saturated conditions and draining conditions after having been saturated for 3 days. Biological degradation\\u000a of 17?-estradiol exhibited rapid rates of

Deborah L. Carr; Audra N. Morse; John C. Zak; Todd A. Anderson

2011-01-01

286

SULFUR PESTICIDE REGISTRATION STANDARD  

EPA Science Inventory

The document contains information regarding reregistration of pesticide products containing the subject active ingredient. The document includes how to register under a registration standard, regulatory position and rationale, and summaries of data requirements and data gaps. Als...

287

Peritoneal dialysis patients with high effluent fibrin degradation products.  

PubMed

Encapsulating peritoneal sclerosis (EPS) is a major and fatal complication of peritoneal dialysis (PD). For treatment, the efficacies of steroids, tamoxifen, immunosuppressants, and surgical total intestinal enterolysis have been reported, but the results have not been sufficient. Because treatment after the onset of EPS is limited, a prophylactic therapy is needed. We previously reported that the level of effluent fibrin degradation products (eFDPs) is predictive of EPS. In the present study, we investigated the clinical course of PD cases with high eFDP levels, and the effect of prophylactic steroid therapy against EPS. Between January 2002 and August 2008, we investigated 310 PD patients, of whom 22 had an eFDP level of 30 microg/mL or more in 4-hour effluent from a fast peritoneal equilibration test (PET). Mean patient age was 62.6 +/- 11.1 years, and mean duration of dialysis was 42.7 +/- 45.5 months (range: 1 - 202 months). During a fast PET performed every 6 months, we measured, in 4-hour effluent, eFDPs, cancer antigen 125 (eCA125), and dialysate-to-plasma creatinine (D/P Cr). In addition, we calculated D/P beta2-microglobulin (beta2MG) from levels in overnight dialysis effluent and blood. In the 22 cases, the mean eFDP level was 66.6 +/- 39.2 microg/mL; the D/P Cr 0.78 +/- 0.1; and the D/P beta2MG 0.45 +/- 0.2. Steroid (5 - 30 mg daily) was administered to 8 of the 22 patients. In the 8 treated cases, the eFDP level, the D/P Cr, and the D/P beta2MG declined, but did not return to normal, and EPS developed in 2 patients. The eFDP level was high when dialysis was introduced, but returned to normal in 2 of the remaining 14 patients. In 1 of the 14 cases, peritonitis developed 5 times, followed by rapid elevation in the eFDP level. The patient with this intractable peritonitis was switched to hemodialysis. The other 11 patients received no steroid therapy. In 1 of these 11 patients, the eFDP level declined, but not in the others. We suggest that active steroid therapy for patients with a high level of eFDPs may prevent EPS development. PMID:19886315

Moriishi, Misaki; Kawanishi, Hideki; Tsuchiya, Shinichiro

2009-01-01

288

US EPA, Pesticide Product Label, BETZ ENTEC 349, 01/18 ...  

EPA Pesticide Factsheets

... PESTICIDE DISPOSIL:o. .l eoat ?? ia.t. Mlt.r.'", .rf,I' b, St"',1 ., ';s,ls.I.Ptstici" MI,tIS ." .etI, ."z.'.'.s ''''1' tllie.I"" ,Istiei ??? s"., .ilt,,,.I' ri".t. is I ,i,l.li., I' f ??? ~1 1 ??. lf ...

2011-04-21

289

US EPA, Pesticide Product Label, AQ - 90 TABLETS, 09/29 ...  

EPA Pesticide Factsheets

... aLutdy (.,A'lM'kvso DISPOSAL Of PESTICIDE '~~~~lJrjf:~~l'IrCi!iitfiSjfiiJ3~~: trH~~~::Bts~!P'r ~. Itt 01 excess pes/icicle, ~ay (1lix1U1e.O\\,~g\\QIe is ...

2011-04-21

290

DETECTION OF MUTAGENIC PROPERTIES OF PESTICIDES USED IN COMMERCIAL CORN PRODUCTION  

EPA Science Inventory

This project encompassed the analysis of 21 pesticides and 12 combinations of herbicides for their genotoxic properties. Three genetic assays were employed: reverse mutation in Salmonella typhimurium, gene conversion in S. cerveisiae and reverse mutation in Z. mays. The use of th...

291

Microbial production and degradation of ?-aminobutyric acid (GABA) in the abalone larval settlement habitat  

Microsoft Academic Search

By producing or degrading gamma-aminobutyric acid (GABA), microbes may affect the settlement of abalone (Haliotis) larvae. GABA was not detectable in extracts of crustose red algae (CRA) which are the preferred settlement substratum for Haliotis larvae. The CRA surfaces and their associated biofilms did not produce GABA from glutamate, and GABA production from putrescine required gabaculine (transaminase inhibitor). The GABA-degrading

H. F. Kaspar; D. O. Mountfort

1995-01-01

292

Fate of CL20 in sandy soils: Degradation products as potential markers of natural attenuation  

Microsoft Academic Search

Hexanitrohexaazaisowurtzitane (CL-20) is an emerging explosive that may replace the currently used explosives such as RDX and HMX, but little is known about its fate in soil. The present study was conducted to determine degradation products of CL-20 in two sandy soils under abiotic and biotic anaerobic conditions. Biotic degradation was prevalent in the slightly acidic VT soil, which contained

Fanny Monteil-Rivera; Annamaria Halasz; Dominic Manno; Roman G. Kuperman; Sonia Thiboutot; Guy Ampleman; Jalal Hawari

2009-01-01

293

CHEMICAL NATURE AND IMMUNOTOXICOLOGICAL PROPERTIES OF ARACHIDONIC ACID DEGRADATION PRODUCTS FORMED BY EXPOSURE TO OZONE  

EPA Science Inventory

Ozone (O3) exposure in vivo has been reported to degrade arachidonic acid (AA) in the lungs of rodents. The O3-degraded AA products may play a role in the lung responses to this toxicant. In order to study the chemical nature and biological activity of O3-exposed AA, we exposed A...

294

Spectroscopic study of degradation products of ciprofloxacin, norfloxacin and lomefloxacin formed in ozonated wastewater.  

PubMed

This study addressed the formation and properties of degradation products of ciprofloxacin, norfloxacin and lomefloxacin formed during ozonation of secondary wastewater effluent containing these fluoroquinolone antibiotics. The generation of the degradation products was interpreted in the context of transformations of effluent organic matter (EfOM) tracked via absorbance measurements. The structures of 20 degradation products were elucidated for ciprofloxacin and norfloxacin, respectively. 27 degradation products were identified for lomefloxacin. The prevalent oxidation pathways were suggested based on the structures of the identified products formed in the absence and presence of the hydroxyl radical scavenger t-butanol. These pathways were largely similar for all studied fluoroquinolones and involved attacks on the piperazine ring and the quinolone structure. The quinolone ring remained intact in the presence of t-butanol thus indicating that this functional group could only be oxidized by OH radicals while the piperazine ring was readily oxidized by molecular ozone. The cleavage of the quinolone moiety that resulted in several identified degradation products occurred via the attack by hydroxyl radicals on the carbon-carbon double bond adjacent to the carboxylic acid group. Lomefloxacin had more diverse oxidation products due to the presence of a methyl group on its piperazinyl ring. The concentrations of the identified degradation products behaved non-monotonically as a function of ozone dose or treatment time, yet exhibited interpretable correlations versus changes of EfOM absorbance. Examination of these correlations allowed developing a novel approach for elucidating the transformations of fluoroquinolone antibiotics during ozonation. PMID:22863026

Liu, Chen; Nanaboina, Venkateswarlu; Korshin, Gregory V; Jiang, Wenju

2012-07-20

295

Degradation of human collagen isoforms by Clostridium collagenase and the effects of degradation products on cell migration.  

PubMed

Clostridium collagenase has been widely used in biomedical research to dissociate tissues and isolate cells; and, since 1965, as a therapeutic drug for the removal of necrotic wound tissues. Previous studies found that purified collagenase-treated extracellular matrix stimulated cellular response to injury and increased cell proliferation and migration. This article presents an in vitro study investigating the digestive ability of Clostridium collagenase on human collagen types I, III, IV, V and VI. Our results showed that Clostridium collagenase displays proteolytic power to digest all these types of human collagen, except type VI. The degradation products derived were tested in cell migration assays using human keratinocytes (gold surface migration assay) and fibroblasts (chemotaxis cell migration assay). Clostridium collagenase itself and the degradation products of type I and III collagens showed an increase in keratinocyte and fibroblast migration, type IV-induced fibroblast migration only, and the remainder showed no effects compared with the control. The data indicate that Clostridium collagenase can effectively digest collagen isoforms that are present in necrotic wound tissues and suggest that collagenase treatment provides several mechanisms to enhance cell migration: collagenase itself and collagen degradation products. PMID:20529148

Shi, Lei; Ermis, Ryan; Garcia, Anastacia; Telgenhoff, Dale; Aust, Duncan

2010-04-01

296

METHOXYCHLOR AND DDT DEGRADATION IN WATER: RATES AND PRODUCTS  

EPA Science Inventory

Methoxychlor (2,2-bis(methoxyphenyl)-1,1,1-trichloroethane) and DDT (2,2-bis(chlorophenyl)-1,1,1-trichloroethane) undergo different hydrolytic degradation pathways in water at pH's common to the aquatic environment. For methoxychlor at common aquatic pH's, the reaction is pH inde...

297

Herbicides and herbicide degradation products in upper midwest agricultural streams during august base-flow conditions  

USGS Publications Warehouse

Herbicide concentrations in streams of the U.S. Midwest have been shown to decrease through the growing season due to a variety of chemical and physical factors. The occurrence of herbicide degradation products at the end of the growing season is not well known. This study was conducted to document the occurrence of commonly used herbicides and their degradation products in Illinois, Iowa, and Minnesota streams during base-flow conditions in August 1997. Atrazine, the most frequently detected herbicide (94%), was present at relatively low concentrations (median 0.17 ??g L-1). Metolachlor was detected in 59% and cyanazine in 37% of the samples. Seven of nine compounds detected in more than 50% of the samples were degradation products. The total concentration of the degradation products (median of 4.4 ??g L-1) was significantly greater than the total concentration of parent compounds (median of 0.26 ??g L-1). Atrazine compounds were present less frequently and in significantly smaller concentrations in streams draining watersheds with soils developed on less permeable tills than in watersheds with soils developed on more permeable loess. The detection and concentration of triazine compounds was negatively correlated with antecedent rainfall (April-July). In contrast, acetanalide compounds were positively correlated with antecedant rainfall in late spring and early summer that may transport the acetanalide degradates into ground water and subsequently into nearby streams. The distribution of atrazine degradation products suggests regional differences in atrazine degradation processes.

Kalkhoff, S. J.; Lee, K. E.; Porter, S. D.; Terrio, P. J.; Thurman, E. M.

2003-01-01

298

Reaction of hydrogen peroxide with ferrylhemoglobin: superoxide production and heme degradation.  

PubMed

The reaction of Fe(II) hemoglobin (Hb) but not Fe(III) hemoglobin (metHb) with hydrogen peroxide results in degradation of the heme moiety. The observation that heme degradation was inhibited by compounds, which react with ferrylHb such as sodium sulfide, and peroxidase substrates (ABTS and o-dianisidine), demonstrates that ferrylHb formation is required for heme degradation. A reaction involving hydrogen peroxide and ferrylHb was demonstrated by the finding that heme degradation was inihibited by the addition of catalase which removed hydrogen peroxide even after the maximal level of ferrylHb was reached. The reaction of hydrogen peroxide with ferrylHb to produce heme degradation products was shown by electron paramagnetic resonance to involve the one-electron oxidation of hydrogen peroxide to the oxygen free radical, superoxide. The inhibition by sodium sulfide of both superoxide production and the formation of fluorescent heme degradation products links superoxide production with heme degradation. The inability to produce heme degradation products by the reaction of metHb with hydrogen peroxide was explained by the fact that hydrogen peroxide reacting with oxoferrylHb undergoes a two-electron oxidation, producing oxygen instead of superoxide. This reaction does not produce heme degradation, but is responsible for the catalytic removal of hydrogen peroxide. The rapid consumption of hydrogen peroxide as a result of the metHb formed as an intermediate during the reaction of reduced hemoglobin with hydrogen peroxide was shown to limit the extent of heme degradation. PMID:11015232

Nagababu, E; Rifkind, J M

2000-10-10

299

The effects of trypsin digested globulin degradation products (TDPG) on the activity of central nervous system.  

PubMed

Studies on trypsin-digested globulin degradation products given to rats intraperitoneally or intraventricularly, revealed psychodepressive effects on the central nervous system. Peptides with a molecular weight of approximately 1,3000 were the most active. PMID:4456425

Wisniewski, K; Tarasiewicz, S; Ma?kowiak, J; Buczko, W; Moniuszko-Jakoniuk, J

1974-01-01

300

21 CFR 864.7320 - Fibrinogen/fibrin degradation products assay.  

Code of Federal Regulations, 2013 CFR

...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7320 Fibrinogen/fibrin degradation products assay. (a) Identification. A...

2013-04-01

301

Generic Rapid Analysis of Current and Prospective Nerve Agents and Their Degradation Products.  

National Technical Information Service (NTIS)

We have developed a rapid and highly reliable analytical methodology for current and prospective nerve agents and their degradation products. The approach is to augment existing analytical methods with a specific enzymatic transformation step. It utilizes...

I. Elashvili M. B. Potter G. Pellar

2005-01-01

302

Determination of trace amounts of chemical warfare agent degradation products in decontamination solutions with NMR spectroscopy.  

PubMed

Decontamination solutions are used for an efficient detoxification of chemical warfare agents (CWAs). As these solutions can be composed of strong alkaline chemicals with hydrolyzing and oxidizing properties, the analysis of CWA degradation products in trace levels from these solutions imposes a challenge for any analytical technique. Here, we present results of application of nuclear magnetic resonance spectroscopy for analysis of trace amounts of CWA degradation products in several untreated decontamination solutions. Degradation products of the nerve agents sarin, soman, and VX were selectively monitored with substantially reduced interference of background signals by 1D 1H-31P heteronuclear single quantum coherence (HSQC) spectrometry. The detection limit of the chemicals was at the low part-per-million level (2-10 microg/mL) in all studied solutions. In addition, the concentration of the degradation products was obtained with sufficient confidence with external standards. PMID:17973498

Koskela, Harri; Rapinoja, Marja-Leena; Kuitunen, Marja-Leena; Vanninen, Paula

2007-11-01

303

Methods of Analysis by the U.S. Geological Survey National Water Quality Laboratory - Determination of Moderate-Use Pesticides and Selected Degradates in Water by C-18 Solid-Phase Extraction and Gas Chromatography/Mass Spectrometry  

USGS Publications Warehouse

A method for the isolation and analysis of 21 parent pesticides and 20 pesticide degradates in natural-water samples is described. Water samples are filtered to remove suspended particulate matter and then are pumped through disposable solid-phase-extraction columns that contain octadecyl-bonded porous silica to extract the analytes. The columns are dried by using nitrogen gas, and adsorbed analytes are eluted with ethyl acetate. Extracted analytes are determined by capillary-column gas chromatography/mass spectrometry with selected-ion monitoring of three characteristic ions. The upper concentration limit is 2 micrograms per liter (?g/L) for most analytes. Single-operator method detection limits in reagent-water samples range from 0.00 1 to 0.057 ?g/L. Validation data also are presented for 14 parent pesticides and 20 degradates that were determined to have greater bias or variability, or shorter holding times than the other compounds. The estimated maximum holding time for analytes in pesticide-grade water before extraction was 4 days. The estimated maximum holding time for analytes after extraction on the dry solid-phase-extraction columns was 7 days. An optional on-site extraction procedure allows for samples to be collected and processed at remote sites where it is difficult to ship samples to the laboratory within the recommended pre-extraction holding time. The method complements existing U.S. Geological Survey Method O-1126-95 (NWQL Schedules 2001 and 2010) by using identical sample preparation and comparable instrument analytical conditions so that sample extracts can be analyzed by either method to expand the range of analytes determined from one water sample.

Sandstrom, Mark W.; Stroppel, Max E.; Foreman, William T.; Schroeder, Michael P.

2001-01-01

304

Effects of the herbicide atrazine and its degradation products, alone and in combination, on phototrophic microorganisms  

Microsoft Academic Search

Toxic effects of the herbicide atrazine and four of its degradation products were determined for growth, photosynthesis, and acetylene-reducing ability of two species of green algae and three species of cyanobacteria. Atrazine was significantly more toxic than its degradation products towards the above test criteria, yielding EC50 values ranging from 0.1 to 0.5 ppm (µg\\/ml) for photosynthesis and 0.03 to

Glenn W. Stratton

1984-01-01

305

The expanding role of LCMS in analyzing metabolites and degradation products of food contaminants  

Microsoft Academic Search

Liquid chromatography-mass spectrometry (LC-MS) has contributed significantly in advancing research in the analysis of metabolites and degradation products of food contaminants. Of particular interest is the comprehensive application of LC-MS to discovery of degradation products and metabolites. This review, covering research published between 2003 and 2008, describes how LC-MS has been used in this field, with the majority of work

Damià Barceló

2008-01-01

306

Glucose degradation products (GDP) retard remesothelialization independently of D-glucose concentration  

Microsoft Academic Search

Glucose degradation products (GDP) retard remesothelialization independently of D-glucose concentration.BackgroundGlucose degradation products (GDP) present in heat-sterilized dialysis fluids are thought to contribute to cellular dysfunction and membrane damage during peritoneal dialysis. To examine the effects of specific GDP on the remesothelialization process, the impact of conventional and low GDP peritoneal dialysis solutions, D-glucose, and individual GDP in a scratch-wounding model

Llinos W. Morgan; Anders Wieslander; Malcolm Davies; Takashi Horiuchi; Yuji Ohta; M. Janine Beavis; Kathryn J. Craig; John D. Williams; Nicholas Topley

2003-01-01

307

Microbial degradation and humification of the lawn care pesticide 2,4-dichlorophenoxyacetic acid during the composting of yard trimmings.  

PubMed Central

The fate of the widely used lawn care herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) during the composting of yard trimmings consisting of primarily leaves and grass is an important unexplored question. In this study, we determined the extent of 2,4-D mineralization, incorporation into humic matter, volatilization, and sorption during the composting of yard trimmings. Yard trimmings (2:1 [wt/wt] leaves-grass) were amended with 14C-ring-labeled 2,4-D (17 mg/kg of dry weight) and composted in a temperature-controlled laboratory scale compost system. During composting, thermophilic microbes were numerically dominant, reaching a maximum of 2 x 10(11)/g. At the end of composting, 46% of the organic matter (OM) present in the yard trimmings was lost and the compost was stable, with an oxygen uptake rate of 0.09 mg of O2 per g of OM per h, and was well humified (humification index, 0.39). Mineralization of the OM temporally paralleled mineralization of 2,4-D. In the final compost, 47% of the added 2,4-D carbon was mineralized, about 23% was complexed with high-molecular-weight humic acids, and about 20% was not extractable (humin fraction). Less than 1% of the added 14C was present in water expressed from the finished compost, suggesting a low potential for leaching of 2,4-D. Very little volatilization of 2,4-D occurred during composting. It is of interest that our results indicate active mineralization of 2,4-D at composting temperatures of 60 degrees C because microbial 2,4-D degradation at thermophilic temperatures has not been previously documented.

Michel, F C; Reddy, C A; Forney, L J

1995-01-01

308

Procyanidins modify insulinemia by affecting insulin production and degradation.  

PubMed

Previous studies from our research group have suggested that procyanidins modify glycemia and insulinemia. The aim of this work was to evaluate the effects of procyanidins on ?-cell functionality in a nonpathological system. Four groups of healthy rats were studied. The animals were given daily acute doses of grape seed procyanidin extract (GSPE) for different time periods and at different daily amounts. A ?-cell line (INS-1E) was treated with 25 mg GSPE/L for 24 h to identify possible mechanisms of action for the procyanidins. In vivo experiments showed that different doses of GSPE affected insulinemia in different ways by modifying ?-cell functionality and/or insulin degradation. The islets isolated from rats that were treated with 25 mg GSPE/kg of body weight for 45 days exhibited a limited response to glucose stimulation. In addition, insulin gene expression, insulin synthesis and expression of genes related to insulin secretion were all down-regulated. In vitro studies revealed that GSPE decreased the ability of ?-cells to secrete insulin in response to glucose. GSPE increased glucose uptake in ?-cells under high-glucose conditions but impaired glucose-induced mitochondrial hyperpolarization, decreased adenosine triphosphate (ATP) synthesis and altered cellular membrane potentials. GSPE also modified Glut2, glucokinase and Ucp2 gene expression as well as altered the expression of hepatic insulin-degrading enzyme (Ide), thereby altering insulin degradation. At some doses, procyanidins changed ?-cell functionality by modifying insulin synthesis, secretion and degradation under nonpathological conditions. Membrane potentials and Ide provide putative targets for procyanidins to induce these effects. PMID:22444499

Castell-Auví, Anna; Cedó, Lídia; Pallarès, Victor; Blay, M Teresa; Pinent, Montserrat; Motilva, M José; Garcia-Vallvé, Santiago; Pujadas, Gerard; Maechler, Pierre; Ardévol, Anna

2012-03-22

309

Relationship between in situ degradation kinetics and in vitro gas production fermentation using different mathematical models  

Microsoft Academic Search

In vitro and in situ studies were conducted to evaluate the influence of different mathematical models, used to fit gas production profiles of 15 feedstuffs, on estimates of nylon bag organic matter (OM) degradation kinetics. The gas production data were fitted to Exponential, Logistic, Gompertz and a Sigmoidal model. Using only gas production parameters allowed poor prediction of in situ

M. A. M. Rodrigues; J. W. Cone; L. M. M. Ferreira; M. C. Blok; C. V. M. Guedes

2009-01-01

310

Electrochemical biosensors for rapid determination of pesticide residues in agricultural products  

NASA Astrophysics Data System (ADS)

The biosensors, consisting of immobilized antibodies which were for specific recognition to target molecules and electrodes which were able to convert the binding event between antigen and antibody to a detectable signal, were developed for rapid detection of organophosphate (OPs) pesticides. Anti-OPs antibodies were immobilized onto indium-tin-oxide (ITO) coated interdigitated microsensor electrodes (IMEs). The Faradaic impedance spectra, presented as Nyquist plots (Z' vs Z'') and Bode diagrams, (impedance vs frequency) were recorded in the frequency range from 1Hz to 100 kHz respectively. A linear relationship between the electron-transfer resistance and concentrations of OPs pesticide was found ranging from 0.1 ppm to 100 ppm. The regression equations were Y = 658 X +1861, with the correlation coefficient of 0.977. The biosensing procedure was simple and rapid, and could be completed within 1 h.

Jiang, Xuesong; Wang, Jianping; Ying, Yibin; Ye, Zunzhong; Li, Yanbin

2005-11-01

311

Safe apples for baby-food production: Survey of pesticide treatment regimes leaving minimum residues  

Microsoft Academic Search

A total of 19 pesticide preparations were used according to agricultural practice in six trials in apple orchards. Using gas chromatography–mass spectrometry (GC–MS) and liquid chromatography–tandem mass spectrometry (LC–MS\\/MS), premature Golden Delicious apples collected 64, 50, 36 days before harvest and mature fruit were examined for residues of active ingredients. No residues of triflumuron, triazamate, chlorpyrifos, etofenprox, fenoxycarb, kresoxim-methyl, cyprodinyl,

Jana Ticha; Jana Hajslova; Tomas Kovalczuk; Martin Jech; Jiri Honzicek; Vladimir Kocourek; Miroslav Lansky; Jana Kloutvorova; Vladan Falta

2007-01-01

312

Pesticide Product Use and Risk of Non-Hodgkin Lymphoma in Women  

Microsoft Academic Search

A population-based, incidence case-control study was conducted among women in upstate New York to determine whether pesticide exposure is associated with an increase in risk of non-Hodgkin lymphoma (NHL) among women. The study involved 376 cases of NHL identified through the State Cancer Registry and 463 controls selected from the Medicare beneficiary files and state driver's license records. Information about

Ikuko Kato; Hiroko Watanabe-Meserve; Karen L. Koenig; Mark S. Baptiste; Patricia P. Lillquist; Glauco Frizzera; Jerome S. Burke; Miriam Moseson; Roy E. Shore

2004-01-01

313

Poly(L-lactide)-degrading enzyme production by Actinomadura keratinilytica T16-1 in 3 L airlift bioreactor and its degradation ability for biological recycle.  

PubMed

The optimal physical factors affecting enzyme production in an airlift fermenter have not been studied so far. Therefore, the physical parameters such as aeration rate, pH, and temperature affecting PLA-degrading enzyme production by Actinomadura keratinilytica strain T16-1 in a 3 l airlift fermenter were investigated. The response surface methodology (RSM) was used to optimize PLA-degrading enzyme production by implementing the central composite design. The optimal conditions for higher production of PLA-degrading enzyme were aeration rate of 0.43 vvm, pH of 6.85, and temperature at 46° C. Under these conditions, the model predicted a PLA-degrading activity of 254 U/ml. Verification of the optimization showed that PLA-degrading enzyme production of 257 U/ml was observed after 3 days cultivation under the optimal conditions in a 3 l airlift fermenter. The production under the optimized condition in the airlift fermenter was higher than un-optimized condition by 1.7 folds and 12 folds with un-optimized medium or condition in shake flasks. This is the first report on the optimization of environmental conditions for improvement of PLA-degrading enzyme production in a 3 l airlift fermenter by using a statistical analysis method. Moreover, the crude PLA-degrading enzyme could be adsorbed to the substrate and degraded PLA powder to produce lactic acid as degradation products. Therefore, this incident indicates that PLA-degrading enzyme produced by Actinomadura keratinilytica NBRC 104111 strain T16-1 has a potential to degrade PLA to lactic acid as a monomer and can be used for the recycle of PLA polymer. PMID:22297224

Sukkhum, Sukhumaporn; Tokuyama, Shinji; Kitpreechavanich, Vichien

2012-01-01

314

Ozonation of metoprolol in aqueous solution: ozonation by-products and mechanisms of degradation.  

PubMed

This study investigated the degradation pathway of metoprolol, a widely used ?-blocker, in the ozonation via the identification of generated ozonation by-products (OPs). Structure elucidation of OPs was performed using HPLC coupled with quadrupole time-of-flight high-resolution mass spectrometry. Seven OPs were identified, and four of these have not been reported elsewhere. Identified OPs of metoprolol included aromatic ring breakdown by-products; aliphatic chain degraded by-products and aromatic ring mono-, di-, and tetrahydroxylated derivatives. Based on the detected OPs, metoprolol could be degraded through aromatic ring opening reaction via reaction with ozone (O3) and degradation of aliphatic chain and aromatic ring via reaction with hydroxyl radical (•OH). PMID:23054788

Tay, Kheng Soo; Rahman, Noorsaadah Abd; Abas, Mhd Radzi Bin

2012-10-05

315

Chiral Pesticides: Identification, Description and Environmental Implications  

EPA Science Inventory

Anthropogenic chemicals, including pesticides, are a major source of contamination and pollution in the environment. Pesticides have many positive uses: increased food production, decreased damage to crops and structures, reduced disease vector populations, and more. Nevertheless...

316

Identification and in vitro cytotoxicity of ochratoxin A degradation products formed during coffee roasting.  

PubMed

The mycotoxin ochratoxin A is degraded by up to 90% during coffee roasting. In order to investigate this degradation, model heating experiments with ochratoxin A were carried out, and the reaction products were analyzed by HPLC-DAD and HPLC-MS/MS. Two ochratoxin A degradation products were identified, and their structure and absolute configuration were determined. As degradation reactions, the isomerization to 14-(R)-ochratoxin A and the decarboxylation to 14-decarboxy-ochratoxin A were identified. Subsequently, an analytical method for the determination of these compounds in roasted coffee was developed. Quantification was carried out by HPLC-MS/MS and the use of stable isotope dilution analysis. By using this method for the analysis of 15 coffee samples from the German market, it could be shown that, during coffee roasting, the ochratoxin A diastereomer 14-(R)-ochratoxin A was formed in amounts of up to 25.6% relative to ochratoxin A. The decarboxylation product was formed only in traces. For toxicity evaluations, first preliminary cell culture assays were performed with the two new substances. Both degradation products exhibited higher IC50 values and caused apoptotic effects with higher concentrations than ochratoxin A in cultured human kidney epithelial cells. Thus, these cell culture data suggest that the degradation products are less cytotoxic than ochratoxin A. PMID:18588316

Cramer, Benedikt; Königs, Maika; Humpf, Hans-Ulrich

2008-06-28

317

MONITORING AND MODELLING OF RADIOLYTIC DEGRADATION PRODUCTS OF TBP/n-DODECANE  

SciTech Connect

The Plutonium Uranium Extraction (PUREX) solvent system was developed for the separation of plutonium and uranium from irradiated fuel. Since the implementation of this process, the degradation chemistry associated with the irradiated solvent system, tributyl phosphate (TBP)/n-dodecane/nitric acid has been extensively studied as the integrity of the organic solvent is paramount for reproducible performance of the separation flowsheet (extraction/scrub/strip) during multiple cycles. In PUREX-like processes, the extent of decomposition is dependent not only upon the solvent, but also upon the presence of constituents, such as nitric acid, that interact with TBP and increase its susceptibility to radiolytic degradation. The build-up of degradation products in the organic phase alters process flowsheet performance via modification of the metal ions speciation, loss of solvent components, and enhanced water transport into the organic phase. On-line identification and quantification of the solvent degradation products would provide the necessary information for more detailed process control as well as providing the basis for timing solvent washing or replacement. In our research, we are exploring the potential of on-line monitoring for the PUREX solvent radiolytic degradation products. To identify degradation products, TBP/n-dodecane solvent, contacted with aqueous nitric acid solutions of variable concentrations are subjected to various gamma radiation external doses then analyzed by electro-spray ionization mass spectrometry (ESMS). In addition, vibrational spectroscopy is utilized to monitor and quantify major degradation products including dibutyl phosphoric acid (HDBP) and monobutyl phosphoric acid (H2MBP) in TBP/n-dodecane solvent. The compiled spectroscopic databases serve for developing interpretive and predictive chemometric models for the quantification of the PUREX solvent degradation products.

Peterson, James M.; Levitskaia, Tatiana G.; Bryan, Samuel A.

2011-10-03

318

Activity of meadowfoam (Limnanthes alba) seed meal glucolimnanthin degradation products against soilborne pathogens.  

PubMed

Meadowfoam (Limnanthes alba L.) is a herbaceous winter-spring annual grown as a commercial oilseed crop. The meal remaining after oil extraction from the seed contains up to 4% of the glucosinolate glucolimnanthin. Degradation of glucolimnanthin yields toxic breakdown products, and therefore the meal may have potential in the management of soilborne pathogens. To maximize the pest-suppressive potential of meadowfoam seed meal, it would be beneficial to know the toxicity of individual glucolimnanthin degradation products against specific soilborne pathogens. Meloidogyne hapla second-stage juveniles (J2) and Pythium irregulare and Verticillium dahliae mycelial cultures were exposed to glucolimnanthin as well as its degradation products. Glucolimnanthin and its degradation product, 2-(3-methoxyphenyl)acetamide, were not toxic to any of the soilborne pathogens at concentrations up to 1.0 mg/mL. Two other degradation products, 2-(3-methoxymethyl)ethanethioamide and 3-methoxyphenylacetonitrile, were toxic to M. hapla and P. irregulare but not V. dahliae. The predominant enzyme degradation product, 3-methoxybenzyl isothiocyanate, was the most toxic compound against all of the soilborne pathogens, with M. hapla being the most sensitive with EC(50) values (0.0025 ± 0.0001 to 0.0027 ± 0.0001 mg/mL) 20-40 times lower than estimated EC(50) mortality values generated for P. irregulare and V. dahliae (0.05 and 0.1 mg/mL, respectively). The potential exists to manipulate meadowfoam seed meal to promote the production of specific degradation products. The conversion of glucolimnanthin into its corresponding isothiocyanate should optimize the biopesticidal properties of meadowfoam seed meal against M. hapla, P. irregulare, and V. dahliae. PMID:22142246

Zasada, Inga A; Weiland, Jerry E; Reed, Ralph L; Stevens, Jan F

2011-12-16

319

Pesticide Program Pesticide Monitoring Database 2007  

Center for Food Safety and Applied Nutrition (CFSAN)

... Pesticide Program Pesticide Monitoring Database 2007. ... A report based on the information in this database is also available. ... More results from www.fda.gov/food/foodborneillnesscontaminants/pesticides

320

Determination of pesticides associated with suspended sediments in the San Joaquin River, California, USA, using gas chromatography-ion trap mass spectrometry  

USGS Publications Warehouse

An analytical method useful for the quantification of a range of pesticides and pesticide degradation products associated with suspended sediments was developed by testing a variety of extraction and cleanup schemes. The final extraction and cleanup methods chosen for use are suitable for the quantification of the listed pesticides using gas chromatography-ion trap mass spectrometry and the removal of interfering coextractable organic material found in suspended sediments. Methylene chloride extraction followed by Florisil cleanup proved most effective for separation of coextractives from the pesticide analytes. Removal of elemental sulfur was accomplished with tetrabutylammonium hydrogen sulfite. The suitability of the method for the analysis of a variety of pesticides was evaluated, and the method detection limits (MDLs) were determined (0.1-6.0 ng/g dry weight of sediment) for 21 compounds. Recovery of pesticides dried onto natural sediments averaged 63%. Analysis of duplicate San Joaquin River suspended-sediment samples demonstrated the utility of the method for environmental samples with variability between replicate analyses lower than between environmental samples. Eight of 21 pesticides measured were observed at concentrations ranging from the MDL to more than 80 ng/g dry weight of sediment and exhibited significant temporal variability. Sediment-associated pesticides, therefore, may contribute to the transport of pesticides through aquatic systems and should be studied separately from dissolved pesticides.

Bergamaschi, B. A.; Baston, D. S.; Crepeau, K. L.; Kuivila, K. M.

1999-01-01

321

The ARS Pesticide Properties Database  

NSDL National Science Digital Library

Maintained by the Agricultural Research Service's (ARS) Remote Sensing and Modeling Lab, the ARS Pesticide Properties Database "is a compendium of chemical and physical properties of 324 widely used pesticides." The database, organized alphabetically, focuses on "16 of the most important properties" affecting pesticide transport and degradation characteristics under different soil and weather conditions. For each pesticide, users will find information on CASRN, Molecular formula, Molecular weight, Physical state, Boiling point, Melting point, Decomposition point, Heat of vaporization, Rate Constants-Hydrolysis (Photolysis), Vapor pressure, Water solubility, Organic solubility, Henry's Law, Octanol/ water partitioning, Acid dissociation, Soil sorption, Field dissipation, and Soil halflife (aerobic, anaerobic). Also provided are several sections describing the properties and units of pesticide parameters, a Coden list, and links to a few related sites.

2005-12-06

322

The ARS Pesticide Properties Database  

NSDL National Science Digital Library

Maintained by the Agricultural Research Service's (ARS) Remote Sensing and Modeling Lab, the ARS Pesticide Properties Database "is a compendium of chemical and physical properties of 324 widely used pesticides." The database, organized alphabetically, focuses on "16 of the most important properties" affecting pesticide transport and degradation characteristics under different soil and weather conditions. For each pesticide, users will find information on CASRN, Molecular formula, Molecular weight, Physical state, Boiling point, Melting point, Decomposition point, Heat of vaporization, Rate Constants-Hydrolysis (Photolysis), Vapor pressure, Water solubility, Organic solubility, Henry's Law, Octanol/ water partitioning, Acid dissociation, Soil sorption, Field dissipation, and Soil halflife (aerobic, anaerobic). Also provided are several sections describing the properties and units of pesticide parameters, a Coden list, and links to a few related sites.

2005-01-01

323

Generation of toxic degradation products by sonication of Pluronic® dispersants: implications for nanotoxicity testing.  

PubMed

Abstract Poloxamers (known by the trade name Pluronic®) are triblock copolymer surfactants that contain two polyethylene glycol blocks and one polypropylene glycol block of various sizes. Poloxamers are widely used as nanoparticle dispersants for nanotoxicity studies wherein nanoparticles are sonicated with a dispersant to prepare suspensions. It is known that poloxamers can be degraded during sonication and that reactive oxygen species contribute to the degradation process. However, the possibility that poloxamer degradation products are toxic to mammalian cells has not been well studied. We report here that aqueous solutions of poloxamer 188 (Pluronic® F-68) and poloxamer 407 (Pluronic® F-127) sonicated in the presence or absence of multi-walled carbon nanotubes (MWNTs) can became highly toxic to cultured cells. Moreover, toxicity correlated with the sonolytic degradation of the polymers. These findings suggest that caution should be used in interpreting the results of nanotoxicity studies where the potential sonolytic degradation of dispersants was not controlled. PMID:23030523

Wang, Ruhung; Hughes, Tyler; Beck, Simon; Vakil, Samee; Li, Synyoung; Pantano, Paul; Draper, Rockford K

2012-10-29

324

Treatment of low level radioactive liquid waste containing appreciable concentration of TBP degraded products.  

PubMed

The acidic and alkaline low level radioactive liquid waste (LLW) generated during the concentration of high level radioactive liquid waste (HLW) prior to vitrification and ion exchange treatment of intermediate level radioactive liquid waste (ILW), respectively are decontaminated by chemical co-precipitation before discharge to the environment. LLW stream generated from the ion exchange treatment of ILW contained high concentrations of carbonates, tributyl phosphate (TBP) degraded products and problematic radio nuclides like (106)Ru and (99)Tc. Presence of TBP degraded products was interfering with the co-precipitation process. In view of this a modified chemical treatment scheme was formulated for the treatment of this waste stream. By mixing the acidic LLW and alkaline LLW, the carbonates in the alkaline LLW were destroyed and the TBP degraded products got separated as a layer at the top of the vessel. By making use of the modified co-precipitation process the effluent stream (1-2 ?Ci/L) became dischargeable to the environment after appropriate dilution. Based on the lab scale studies about 250 m(3) of LLW was treated in the plant. The higher activity of the TBP degraded products separated was due to short lived (90)Y isotope. The cement waste product prepared using the TBP degraded product was having good chemical durability and compressive strength. PMID:21920663

Valsala, T P; Sonavane, M S; Kore, S G; Sonar, N L; De, Vaishali; Raghavendra, Y; Chattopadyaya, S; Dani, U; Kulkarni, Y; Changrani, R D

2011-09-02

325

Identification of Forced Degradation Products of Itopride by LC-PDA and LC-MS  

PubMed Central

Degradation products of itopride formed under different forced conditions have been identified using LC-PDA and LC-MS techniques. Itopride was subjected to forced degradation under the conditions of hydrolysis, photolysis, oxidation, dry and wet heat, in accordance with the International Conference on Harmonization. The stress solutions were chromatographed on reversed phase C18 (250×4.6 mm, 5 ?m) column with a mobile phase methanol:water (55:45, v/v) at a detection wavelength of 215 nm. Itopride degraded in acid, alkali and oxidative stress conditions. The stability indicating method was developed and validated. The degradation pathway of the drug to products II-VIII is proposed.

Joshi, Payal; Bhoir, Suvarna; Bhagwat, A. M.; Vishwanath, K.; Jadhav, R. K.

2011-01-01

326

[The structure and antimicrobial activity of the partial degradation products of the antibiotic eremomycin].  

PubMed

Antimicrobial activity of partial degradation products of eremomycin, a new glycopeptide antibiotic, was studied. The products formed by eremomycin deglycosylation (deseremosaminyl eremomycin, eremosaminyl aglycone and aglycone) and elimination of the chlorine atom from the molecule aglycone moiety (dechloroeremomycin). The spectral data in favour of the compounds structure are presented. It was found that partial degradation led to a decrease in the antimicrobial activity of the antibiotic. Dechloreremomycin had the highest activity among the products. Its MIC for the methicillin-resistant strains of Staphylococcus aureus was only twice as low as that of the initial antibiotic. PMID:1910324

Berdnikova, T F; Lomakina, N N; Olsuf'eva, E N; Aleksandrova, L G; Potapova, N P; Rozynov, B V; Malkova, I V; Orlova, G I

1991-06-01

327

The Need for Strategic Environmental Assessment of Fishery Products Regulations in the Taiwan Strait: Taking Health Perspectives of Organochlorine Pesticides in Seafood as an Example  

Microsoft Academic Search

This article proposes an integrated Health Impact Assessment\\/Strategic Environmental Assessment (HIA\\/SEA) framework that can be applied to fishery products regulations in Taiwan Strait. In recent years, many studies with regards to organochlorine pesticides (OCPs), especially DDT and its derivatives, in Taiwan's environment and aquatic biota indicated that DDT, DDD, and DDE in seafood, especially oysters, in the Kinmen, Manchu area

Ming-Lone Liou; Shin-Cheng Yeh; Yong-Chien Ling; Chien-Min Chen

2006-01-01

328

Effect of organic, low-input and conventional production systems on pesticide and growth regulator residues in wheat, potato and cabbage  

Microsoft Academic Search

The Nafferton factorial systems comparison (NFSC) experiments facilitate the investigation of effects of, and interaction between, three production system components - a) rotational position, b) fertility and c) crop protection management - in organic, conventional and low-input crop management systems. This paper presents first results on pesticide and growth regulator residues observed over a period of two years. Residues were

L. Lueck; J. M. Cooper; P. N. Shotton; J. Hajslova; V. Schulzova

2007-01-01

329

Time-dependent integrity during storage of natural surface water samples for the trace analysis of pharmaceutical products, feminizing hormones and pesticides  

Microsoft Academic Search

Monitoring and analysis of trace contaminants such as pharmaceuticals and pesticides require the preservation of the samples before they can be quantified using the appropriate analytical methods. Our objective is to determine the sample shelf life to insure proper quantification of ultratrace contaminants. To this end, we tested the stability of a variety of pharmaceutical products including caffeine, natural steroids,

Khadija Aboulfadl; Cyril De Potter; Michèle Prévost; Sébastien Sauvé

2010-01-01

330

Feasibility study of polyhydroxyalkanote production for materials recycling using naturally occurring pollutant degraders  

Microsoft Academic Search

For eco-friendly recycling and reuses of biomaterials with sustainability, this feasibility study tended to use indigenous pollutant degrading bacteria for the production of biodegradable polymers – polyhydroxyalkanotes (PHAs) during wastewater treatment. First, feasible PHA-producing strains were qualitatively screened among pollutant-degrading microbes via Sudan black B staining (SB staining). Next, according to batch cultures using lauric acid as sole carbon source,

Bor-Yann Chen; Tz-Jau Shiau; Yu-Hong Wei; Wen-Ming Chen; Bing-Hua Yu; Chia-Yi Yen; Chung-Chuan Hsueh

331

Hydrolysis patterns and the production of peptide intermediates during protein degradation in marine systems  

Microsoft Academic Search

Matrix-assisted laser desorption\\/ionization time of flight mass spectrometry (MALDI-TOF-MS) was used to evaluate the degradation of the protein bovine serum albumin (BSA) added to seawater. The production of peptides during degradation, the size of the peptides produced and the within-protein locations of protease attack were all monitored in an effort to evaluate whether specific types of proteases or specific peptide

Brook L. Nunn; Angela Norbeck; Richard G. Keil

2003-01-01

332

HPLC analysis, isolation and identification of a new degradation product in carvedilol tablets  

Microsoft Academic Search

Carvedilol (CV) is an antagonist of ?1 and ?1,?2 membrane adrenoceptors and also a modulator of cardiac electrophysiological properties. It is widely prescribed for the treatment of cardiovascular diseases. During stability testing of CV solid dosage forms an unknown degradation product referred as UP, exceeded the identification thresholds of ICH Q3B guidelines. The HPLC analysis of the detected unknown product

Olga Galanopoulou; Stavroula Rozou; Ekaterini Antoniadou-Vyza

2008-01-01

333

Reduced systemic advanced glycation endproducts in children receiving peritoneal dialysis with low glucose degradation product content  

Microsoft Academic Search

Background. Glucose degradation products (GDP) in peritoneal dialysis (PD) solutions are toxic to the peritoneal membrane and promote the formation of advanced glycation end products (AGE), which con- tribute to accelerated atherosclerosis and amyloidosis. Double chamber PD solutions have a markedly reduced GDP content. Methods. We analysed GDP and AGE kinetics in 21 children (7 months to 18 years) on

Claus Peter Schmitt; Dorothee von Heyl; Susanne Rieger; Klaus Arbeiter; Klaus Eugen Bonzel; Michel Fischbach; Joachim Misselwitz; Ann-Kathrin Pieper; Franz Schaefer

334

The influence of core degradation phenomena on in-vessel fission product behavior during severe accidents  

Microsoft Academic Search

In-vessel core degradation phenomena influence where fission products will be located and in what chemical forms they will exist and with what materials they will be associated at the time the lower vessel fails in an unmitigated accident sequence. Fission products released from the reactor vessel during the in-vessel phase of core melt progression in a severe reactor accident can

R. R. Hobbins; D. J. Osetek; D. A. Petti; D. L. Hagrman

1988-01-01

335

Soil Degradation and Soil Productivity Restoration and Maintenance in Hilly Land of Southern China  

Microsoft Academic Search

Soil fertility degeneration and land productivity loss caused by soil erosion are severe problems in hilly land of southern China. A long term field experiment was conducted during 1984 to 1993 to determine soil productivity in a typical degraded hilly area of purple soil (orthic Entisol) in Yanting, Sichuan, China. Results showed that a conservation tillage system with ridge-furrow cropping

Bo Zhu; Meirong Gao; Gangcai Liu; Jianhui Zhang; Shi Chen; Xianwan Zhang

2002-01-01

336

The white-rot fungus Phanerochaete chrysosporium: conditions for the production of lignin-degrading enzymes.  

PubMed

Investigating optimal conditions for lignin-degrading peroxidases production by Phanerochaete chrysosporium (P. chrysosporium) has been a topic for numerous researches. The capability of P. chrysosporium for producing lignin peroxidases (LiPs) and manganese peroxidases (MnPs) makes it a model organism of lignin-degrading enzymes production. Focusing on compiling and identifying the factors that affect LiP and MnP production by P. chrysosporium, this critical review summarized the main findings of about 200 related research articles. The major difficulty in using this organism for enzyme production is the instability of its productivity. This is largely due to the poor understanding of the regulatory mechanisms of P. chrysosporium responding to different nutrient sources in the culture medium, such as metal elements, detergents, lignin materials, etc. In addition to presenting the major conclusions and gaps of the current knowledge on lignin-degrading peroxidases production by P. chrysosporium, this review has also suggested further work, such as correlating the overexpression of the intra and extracellular proteins to the nutrients and other culture conditions to discover the regulatory cascade in the lignin-degrading peroxidases production process, which may contribute to the creation of improved P. chrysosporium strains leading to stable enzyme production. PMID:18810426

Singh, Deepak; Chen, Shulin

2008-09-20

337

Application of degradation test data to advertisement of consumer electronic products  

Microsoft Academic Search

Two kinds of reliability tests (accelerated life test and degradation test) are often performed in the process of developing a new electronic product in order to guarantee its improved performance over the lifetime. As a result of such tests, several reliability indices (parameters) can be estimated. Advertisers of a new product can utilise one of these indices as a benchmarking

So Young Sohn

2000-01-01

338

The dioxin/POPs legacy of pesticide production in Hamburg: part 2--waste deposits and remediation of Georgswerder landfill.  

PubMed

?-HCH, ?-HCH, and ?-HCH (lindane) were listed as persistent organic pollutants in the Stockholm Convention. Therefore, they need to be globally addressed including the wastes remaining from historic use and production. While at most lindane production sites the unintentionally produced 85% HCH waste isomers have been deposited, at a former pesticide factory in Hamburg-Moorfleet HCH waste isomers have been recycled from 1953 to 1984 by thermal decomposition to chlorobenzenes and resulted in high polychlorinated dibenzo-p-dioxin/polychlorinated dibenzofuran (PCDD/PCDF)-contaminated residues. The management of the PCDD/PCDF-contaminated waste from the former pesticide factory in Hamburg has been assessed and quantified. Based on past accredited PCDD/PCDF measurements, the registered 3,700 tonnes of disposed thermal HCH decomposition residue contained 333 to 854 kg of PCDD/PCDF toxicity equivalent (I-TEQ) in 53-102 tonnes total sum of PCDD/PCDF. The wastes have been deposited together with other wastes in landfills in Hamburg and other parts of Germany. For the Georgswerder landfill (Hamburg), where approximately 50% of the PCDD/PCDF is disposed, current and previous situation and remediation activities are described. While PCDD/PCDF leaching from the landfill is controlled and incinerated, more water soluble organochlorines (vinyl chloride, cis-1,2-dichlorethene, chlorobenzenes) and benzene remain as a challenge for groundwater management. A comprehensive aftercare program has been established and will need to be operated by future generations including renewal of containment systems. Former lindane/HCH productions need-in addition to HCH deposits-to be assessed for possible recycling practice of HCH and related PCDD/PCDF-containing deposits. This could systematically be addressed within the Stockholm Convention implementation. PMID:22777611

Götz, Rainer; Sokollek, Volker; Weber, Roland

2012-07-10

339

A mass spectrometry-based method to measure dialkylphosphate degradation products of organophosphorous insecticides in dust and orange juice.  

PubMed

Dialkylphosphates (DAPs) are urinary metabolites and breakdown products of organophosphorous (OP) pesticides. Urinary DAPs are widely used to assess exposure to OP pesticides in epidemiologic studies. Recent evidence suggests that preformed DAPs are present in food and that they may also be present in other parts of the environment. Thus, DAP concentrations observed in urine may reflect a person's exposure to both parent OP pesticides and preformed DAPs in food and other environmental media. The presence of preformed DAPs in multiple media may indicate that previous studies have overestimated exposure to OP pesticides and that the use of urinary DAPs as biomarkers of exposure for OP pesticides may not accurately characterize exposure in non-acute settings. To establish the presence of DAPs in environmental and food media, we developed analytical methods to measure six DAPs in dust and orange juice. The limits of detection (LOD) for the dimethyl phosphates (dimethylphosphate (DMP), dimethylthiophosphate, and dimethyldithiophosphate) ranged from 2.8-9.9 ng g(-1) and 0.2-0.4 ng mL(-1) in dust and juice, respectively. The LODs for the diethyl phosphates (diethylphosphate (DEP), diethylthiophosphate, diethyldithiophosphate) ranged from 5.2-10.4 ng g(-1) and 0.5-3.0 ng mL(-1) in dust and juice, respectively. The extraction efficiencies for the analytes ranged from 23% to 91% and from 41% to 85% in dust and orange juice, respectively. DMP was detected in about half of the dust samples whereas DEP was detected in 80% of the dust samples tested. Other DAPs were less frequently detected in dust. Less than 3% of intact pesticide present in the matrices was converted to their respective DAPs during the pre-analytic and analytic process. Evaluation of the conversion of intact pesticides in the samples to DAPs will help us to better understand the contribution of preformed DAPs to urinary DAP concentrations. PMID:20449223

Weerasekera, Gayanga; Smith, Kimberly D; Quirós-Alcalá, Lesliam; Fernandez, Carolina; Bradman, Asa; Eskenazi, Brenda; Needham, Larry L; Barr, Dana B

2009-04-23

340

Relation of pesticide concentrations to season, streamflow, and land use in seven New Jersey streams  

USGS Publications Warehouse

The presence and variability of pesticides in seven New Jersey streams was documented by analyzing 146 samples collected from the streams from April 1996 through June 1998. The samples were analyzed for 85 pesticides, including 50 herbicides, 28 insecticides, and 7 degradation products, at method detection limits that ranged from 0.001 to 0.018 ?g/L (micrograms per liter). Pesticides were frequently detected; however, concentrations were generally low. The pesticides most frequently detected were atrazine, in 97 percent of the samples; prometon, 96 percent; metolachlor, 95 percent; desethyl-atrazine, 91 percent; simazine, 88 percent; diazinon, 58 percent; alachlor, 56 percent; and carbaryl, 54 percent. Detection frequencies were highest during the growing season (April-September). At least one pesticide was detected in all but one of these samples, and 49 percent of the samples contained 9 or more pesticides. The numbers of pesticides detected at a given site ranged from 13 to 29. Ten pesticides were detected at concentrations that exceeded established water-quality criteria. Thirty-one of these detections were in samples collected during the growing season and one during the nongrowing season. The pesticides that exceeded the U.S. Environmental Protection Agency (USEPA) maximum contaminant level for drinking water were atrazine, which exceeded 3 ?g/L in four samples, and alachlor, 2 ?g/L in two samples. Cyanazine exceeded the USEPA liftime health advisory level (HAL) of 1 ?g/L in two samples. These eight detections occurred during runoff shortly after spring pesticide applications and represent a potential threat to municipal water supplies in the Raritan River basin. Concentrations of chlorpyrifos, chlorthalonil, diazinon, ethyl-parathion, and methyl-azinphos exceeded the chronic life criteria for the protection of aquatic life (ACQR) in 20 samples at four sites during the growing season. Dieldrin was detected in four samples and DDE in two samples at concentrations that exceeded New Jersey Department of Environmental Protection (NJDEP) human health criteria. Individual and total-pesticide concentrations and total numbers of pesticides detected in the samples varied with season and flow conditions. Median and maximum concentrations of most of the pesticides were highest during runoff in the growing season. Pesticide concentrations were typically lower and less variable in the nongrowing season than in the growing season, regardless of changes in hydrologic conditions; however, median concentrations of most pesticides were slightly lower during runoff than during base flow. The median total-pesticide concentration and median total number of pesticides detected were highest and most variable in runoff samples in the growing season. In the nongrowing season, the median total-pesticide concentration was lowest in runoff samples and least variable during base-flow conditions. Median total numbers of pesticides were lowest and least varibale in the nongrowing season during base-flow conditions at most sites. The highest total-pesticide concentrations were detected in samples from the two small agricultural basins (greater than 25 percent of land use is agricultural) during runoff in late spring and early summer. In general, insecticides were detected more frequently and in greater concentrations at urban sites. Concentrations of agricultural herbicides generally decreased with increasing flow at the four sites with less than 10 percent agriculture land use and increased with increasing flow at the three sites with more than 25 percent agricultural land use. Most of the pesticides that correlated positively with streamflow were detected at sites where land use in the basin would indicate the use of those particular pesticides. Most of the pesticides that correlated negatively with streamflow were present at the site in the Coastal Plain or at sites in which the land use in the basin would not indicate heavy u

Reiser, Robert G.

1999-01-01

341

Forced degradation studies of corticosteroids with an alumina-steroid-ethanol model for predicting chemical stability and degradation products of pressurized metered-dose inhaler formulations.  

PubMed

An alumina (Al(2)O(3))-steroid-ethanol model is used for forced degradation testing of corticosteroids to predict chemical stability and degradation products in pressurized metered-dose inhaler (pMDI) solution formulations. The model involves an ethanolic solution of a test steroid with Al(2)O(3), stressed at elevated temperatures to mimic the chemical interaction of drug, excipient, and packaging (an aluminum aerosol canister). The reactivity order of eight synthetic corticosteroids toward Al(2)O(3)-induced reactions is ranked with the stress model. The corticosteroids containing a C21-OH group possess the highest reactivity, suggesting that aluminum canisters with an inert interior coating are needed to stabilize their solution pMDIs. The Al(2)O(3)-induced degradation products and degradation pathways of a steroid containing C21-OH and triamcinolone acetonide are presented, and the role of Al(2)O(3) in the degradation pathways is briefly discussed. A potential degradation profile of beclomethasone dipropionate (BDP) established with an Al(2)O(3)-BDP-ethanol stress model is the same as the actual degradation profile of the BDP pMDI product, indicating that the model indeed predicts the degradation products. PMID:22410760

Wu, Zheng-Zhi; Thatcher, Matthew L; Lundberg, James K; Ogawa, Mark K; Jacoby, Cliffton B; Battiste, John L; Ledoux, Katherine A

2012-03-12

342

Photocatalytic oxidation of pesticide rinsate.  

PubMed

Pesticide rinsate has been considered as one of the major threats for the environment. In this study, photocatalysts such as TiO2 and O3 were used to promote the efficiency of direct UV photolysis to prevent such wastewater pollution. Carbofuran (a carbamate pesticide) and mevinphos (an organophosphate pesticide) with a concentration of 100 mg/L were selected as the test pesticide rinsates. Parent pesticide compound, COD, and microtoxicity analysis were employed to investigate the effect of photocatalyst on the degradation efficiency of pesticide in rinsate. It was found that the photocatalytic oxidation process (UV/O3, UV/TiO2) showed much higher COD removal and microtoxicity reduction efficiency for pesticide rinsate than did direct UV photolysis under the imposed conditions, suggesting that photocatalytic oxidation processes such as UV/O3 and UV/TiO2 could be a better alternative to treat pesticide rinsate. In addition, it was noted that increasing the initial pH of mevinphos rinsate to a basic level was required to reach higher COD removal efficiency and positive microtoxicity reduction efficiency while it was not necessary for the treatment of carbofuran rinsate. PMID:11990360

Kuo, Wen S

2002-01-01

343

Sublethal effects of three pesticides on larval survivorship, growth, and macromolecule production in the aquatic midge, Chironomus tentans (diptera: chironomidae).  

PubMed

Effects of long-term exposure to each of three pesticides including atrazine, DDT, and chlorpyrifos on larval survivorship, growth, and macromolecule (total body protein and RNA) production were evaluated in the aquatic midge, Chironomus tentans, under laboratory conditions. Newly hatched larvae were exposed to atrazine at 30 and 150 microg/L, DDT at 0.01 and 0.05 microg/L, or chlorpyrifos at 0.02 and 0.10 microg/L throughout one life cycle. Larval survivorship was evaluated at 20 d and the end of the test, and larval growth at 20 d. Chlorpyrifos at 0.1 microg/L reduced the midge survivorship by 67% after 20-d exposure. However, neither atrazine nor DDT affected larval survivorship. The ash-free dry weight of midge larvae exposed to chlorpyrifos at 0.1 microg/L was 1.5-fold greater than that of the control whereas neither atrazine nor DDT showed a significant effect on the ash-free dry weight. In addition, exposures of midges to chlorpyrifos at 0.1 microg/L increased the adult emergence rate by 81% as compared to the control although the actual number of adults that emerged from chlorpyrifos-treated larvae was significantly decreased. Both the increased ash-free dry weight of larvae and increased adult emergence rate were likely caused by reduced competition for both food and space among the survivors due to increased larval mortality. Although neither total protein nor total RNA production was significantly affected in larvae exposed to each pesticide for 20 d, a significantly higher number of males over females (ratio = 4) emerged from midges exposed to DDT at 0.05 microg/L. Our study indicates that chronic exposure to low concentrations of chlorpyrifos and DDT results in significant mortality of midge larvae and alteration of the sex ratio of adult emergence, respectively. Because midges are important components of the food web, our results suggest that effects elicited directly or indirectly by long-term pesticide exposures may potentially disrupt both food chains and community structure in aquatic environments. PMID:16865603

Rakotondravelo, Mamy L; Anderson, Troy D; Charlton, Ralph E; Zhu, Kun Yan

2006-07-21

344

Simultaneous Filtration and SolidPhase Extraction Combined with Large-Volume Injection in GC\\/MS for UltraTrace Analysis of Polar Pesticides in Surface Water  

Microsoft Academic Search

A method combining simultaneous filtration and solid-phase extraction (SPE) with large-volume injection (LVI) in gas chromatography\\/mass spectrometry (GC\\/MS) was developed to determine 13 polar pesticides in surface water. The selected pesticides - 4 organophosphorus, 7 organonitrogens and 2 triazine degradation products - were extracted from 0.5-L samples of filtered and raw water using cartridges filled with a silica-bonded material (1

Hassan Sabik; Bernard Rondeau; Pierre Gagnon; Roger Jeannot; Katja Dohrendorf

2003-01-01

345

Degradation and Sorption of Imidacloprid in Dissimilar Surface and Subsurface Soils  

Technology Transfer Automated Retrieval System (TEKTRAN)

Degradation and sorption/desorption are important processes affecting the leaching of pesticides through soil. Once pesticides move past the surface soil layers, subsurface soil physical, chemical, and biological properties significantly affect pesticide fate and the potential for groundwater contam...

346

Model approach for estimating potato pesticide bioconcentration factor  

Microsoft Academic Search

We presented a model that estimates the bioconcentration factor (BCF) of pesticides in potatoes supposing that the pesticide in the soil solution is absorbed by the potato by passive diffusion, following Fick’s second law. The pesticides in the model are nonionic organic substances, traditionally used in potato crops that degrade in the soil according to a first-order kinetic equation. This

Lourival Costa Paraíba; Karen Kataguiri

2008-01-01

347

Analysis of bioremediation of pesticides by soil microorganisms  

NASA Astrophysics Data System (ADS)

The application of new pesticides requires careful monitoring of their distribution in the environment. The effect of the soil microflora on the stability of the [14C]- labelled juvenoid hormone analogue W-328 was estimated. The micro-organisms from two different soil samples were isolated and tested for their ability to decompose W-328. One bacterial strain, yeast and mold isolates, exhibited the degradation activity. The growth characteristics such as pH and temperature optima were determined. The degradation products were estimated using HPLC.

Ruml, Tomas; Klotz, Dietmar; Tykva, R.

1995-10-01

348

Occurrence and distribution of pesticides in surface waters of the Hood River basin, Oregon, 1999-2009  

USGS Publications Warehouse

The U.S. Geological Survey analyzed pesticide and trace-element concentration data from the Hood River basin collected by the Oregon Department of Environmental Quality (ODEQ) from 1999 through 2009 to determine the distribution and concentrations of pesticides in the basin's surface waters. Instream concentrations were compared to (1) national and State water-quality standards established to protect aquatic organisms and (2) concentrations that cause sublethal or lethal effects in order to assess their potential to adversely affect the health of salmonids and their prey organisms. Three salmonid species native to the basin are listed as "threatened" under the U.S. Endangered Species Act: bull trout, steelhead, and Chinook salmon. A subset of 16 sites was sampled every year by the ODEQ for pesticides, with sample collection targeted to months of peak pesticide use in orchards (March-June and September). Ten pesticides and four pesticide degradation products were analyzed from 1999 through 2008; 100 were analyzed in 2009. Nineteen pesticides were detected: 11 insecticides, 6 herbicides, and 2 fungicides. Two of four insecticide degradation products were detected. All five detected organophosphate insecticides and the one detected organochlorine insecticide were present at concentrations exceeding water-quality standards, sublethal effects thresholds, or acute toxicity values in one or more samples. The frequency of organophosphate detection in the basin decreased during the period of record; however, changes in sampling schedule and laboratory reporting limits hindered clear analysis of detection frequency trends. Detected herbicide and fungicide concentrations were less than water-quality standards, sublethal effects thresholds, or acute toxicity values. Simazine, the most frequently detected pesticide, was the only herbicide detected at concentrations within an order of magnitude (factor of 10) of concentrations that impact salmonid olfaction. Some detected pesticides are of concern, not for their toxicity alone, but for their ability to potentiate the harmful impacts of other pesticides, particularly organophosphates, on salmonids or their prey. Many samples contained mixtures of pesticides, but the effects to salmonids of relevant mixtures at environmentally realistic concentrations for the basin are unknown. Trace-element concentration data, although limited, indicate that eight trace elements are also of concern for their potential to harm salmonid health. The dataset is limited with regard to the spatial and seasonal distribution of pesticides and trace elements in all salmonid-bearing streams, the presence of particle-bound pesticides, and the presence of several unmonitored pesticides known to be used in the basin.

Temple, Whitney B.; Johnson, Henry M.

2011-01-01

349

Pesticide regulations and residue problems in Japan  

Microsoft Academic Search

There are three laws concerned with pesticides in Japan. The Agricultural Chemicals Control Law is aimed primarily at ensuring the quality of pesticides and plant-growth regulators and preventing inferior products from reaching the market. The law was amended in 1963 to strengthen regulatory measures for preventing fishery damages. Pesticides with high mammalian toxicity are further controlled by the Poisonous and

K. Fukunaga; Y. Tsukano

1969-01-01

350

The sources, fate, and toxicity of chemical warfare agent degradation products.  

PubMed

We include in this review an assessment of the formation, environmental fate, and mammalian and ecotoxicity of CW agent degradation products relevant to environmental and occupational health. These parent CW agents include several vesicants: sulfur mustards [undistilled sulfur mustard (H), sulfur mustard (HD), and an HD/agent T mixture (HT)]; nitrogen mustards [ethylbis(2-chloroethyl)amine (HN1), methylbis(2-chloroethyl)amine (HN2), tris(2-chloroethyl)amine (HN3)], and Lewisite; four nerve agents (O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothioate (VX), tabun (GA), sarin (GB), and soman (GD)); and the blood agent cyanogen chloride. The degradation processes considered here include hydrolysis, microbial degradation, oxidation, and photolysis. We also briefly address decontamination but not combustion processes. Because CW agents are generally not considered very persistent, certain degradation products of significant persistence, even those that are not particularly toxic, may indicate previous CW agent presence or that degradation has occurred. Of those products for which there are data on both environmental fate and toxicity, only a few are both environmentally persistent and highly toxic. Major degradation products estimated to be of significant persistence (weeks to years) include thiodiglycol for HD; Lewisite oxide for Lewisite; and ethyl methyl phosphonic acid, methyl phosphonic acid, and possibly S-(2-diisopropylaminoethyl) methylphosphonothioic acid (EA 2192) for VX. Methyl phosphonic acid is also the ultimate hydrolysis product of both GB and GD. The GB product, isopropyl methylphosphonic acid, and a closely related contaminant of GB, diisopropyl methylphosphonate, are also persistent. Of all of these compounds, only Lewisite oxide and EA 2192 possess high mammalian toxicity. Unlike other CW agents, sulfur mustard agents (e.g., HD) are somewhat persistent; therefore, sites or conditions involving potential HD contamination should include an evaluation of both the agent and thiodiglycol. PMID:10585900

Munro, N B; Talmage, S S; Griffin, G D; Waters, L C; Watson, A P; King, J F; Hauschild, V

1999-12-01

351

PCB-degrading recombinant bacterium, product for the bioremediation and method of bioremediation  

US Patent & Trademark Office Database

A recombinant bacterium capable to completely degrade or mineralize pollutants such as polychlorobiphenyls (PCBs), which corresponds to Cupriavidus necator strain JMS34, deposited under the access number NRRL B-30817 a product for the bioremediation of environments contaminated with PCBs, where the product includes a bacterial inoculum of this recombinant strain and a method for the bioremediation of environments contaminated with PCBs, which uses this product for the bioremediation.

2011-08-02

352

Composition of the ozonolytic degradation products of the organic matter of Barzasskii sapromyxite coal  

SciTech Connect

The ozonization of Barzasskii sapromyxite coal in chloroform and the composition of ozonolytic degradation products were studied. Water-insoluble high-molecular-weight products were predominant among the ozonization products. A half of water-soluble substances consisted of aliphatic C{sub 5}-C{sub 12} dicarboxylic acids and benzenedicarboxylic acid derivatives. Sapromyxite has been suggested as a substitute for crude petroleum in the manufacture of motor fuels.

S.A. Semenova; Y.F.Patrakov [Russian Academy of Sciences, Kemerovo (Russian Federation). Institute of Coal and Coal Chemistry

2009-04-15

353

Spatial moment analysis of transport of nonlinearly adsorbing pesticides using analytical approximations  

NASA Astrophysics Data System (ADS)

Analytical approximations were derived for solute transport of pesticides subject to Freundlich sorption, and first-order degradation restricted to the liquid phase. Solute transport was based on the convection-dispersion equation (CDE) assuming steady flow. The center of mass (first spatial moment) was approximated both for a non-degraded solute pulse and for a pulse degraded in the liquid phase. The remaining mass (zeroth spatial moment) of a linearly sorbing solute degraded in the liquid phase was found to be a function of only the center of mass (first spatial moment) and the Damköhler number (i.e., the product of degradation rate coefficient and dispersivity divided by flow velocity). This relationship between the zeroth and first spatial moments was shown to apply to nonlinearly sorbing pulses as well. The mass fraction leached of a pesticide subject to Freundlich sorption and first-order degradation in the solution phase only was found to be a function of the Damköhler number and of the dispersivity, so independent of sorption. Hence perceptions of the effects of sorption on pesticide leaching should be reconsidered. These conclusions equally hold for other micropollutants that degrade in the solution phase only.

Beltman, Wim H. J.; Boesten, Jos J. T. I.; van der Zee, Sjoerd E. A. T. M.

2008-05-01

354

Choosing Organic Pesticides over Synthetic Pesticides May Not Effectively Mitigate Environmental Risk in Soybeans  

Microsoft Academic Search

Background: Selection of pesticides with small ecological footprints is a key factor in developing sustainable agricultural systems. Policy guiding the selection of pesticides often emphasizes natural products and organic-certified pesticides to increase sustainability, because of the prevailing public opinion that natural products are uniformly safer, and thus more environmentally friendly, than synthetic chemicals. Methodology\\/Principal Findings: We report the results of

Christine A. Bahlai; Yingen Xue; Cara M. McCreary; Arthur W. Schaafsma; Rebecca H. Hallett

2010-01-01

355

40 CFR 158.2220 - Product performance.  

Code of Federal Regulations, 2013 CFR

... DATA REQUIREMENTS FOR PESTICIDES Antimicrobial Pesticide Data Requirements § 158...Product performance requirement for all antimicrobial pesticides. Each applicant...product performance data requirements for antimicrobial pesticide products. (b)...

2013-07-01

356

Produtos de degradacao do TBP. Separacao e determinacao por cromatografia gasosa. (TBP degradation products. Separation and gas-chromatographic determination).  

National Technical Information Service (NTIS)

A separation method for di butylphosphate, mono butylphosphate and phosphoric acid as degradation products in organic and aqueous streams of the process containing variable amounts of actinides and fission products is described. The products were separate...

T. A. Kuada C. M. Alem H. T. Matsuda B. F. Araujo J. Araujo

1991-01-01

357

Analytical methods for environmental sampling of chemical warfare agents and their degradation products  

SciTech Connect

This first technical conference promoted the standardization of analytical procotols to reliably detect chemical warfare agents and their degradation products in soil, water, and other complex environmental media. This supports the various chemical weapons disposal and emergency preparedness programs, Chemical Weapons Convention treaty compliance, installation restoration and base closure decisions. Five major topics were addressed: Implementation for treaty compliance, installation, restoration and stockpile disposal decisions, existing analytical methods, practical applications of existing analytical techniques, immunoassay technologies, environmental and biological fate of agents and their degradation products. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database.

Watson, A.P. [ed.] [Oak Ridge National Lab., TN (United States); Kistner, S. [ed.] [Army Center for Health Promotion and Preventive Medicine, Aberdeen Proving Ground, MD (United States)

1995-06-01

358

Determination of pesticide residues in fruit-based soft drinks.  

PubMed

Here we report the first worldwide reconnaissance study of the presence and occurrence of pesticides in fruit-based soft drinks. While there are strict regulations and exhaustive controls for pesticides in fruits, vegetables, and drinking water, scarce attention has been paid to highly consumed derivate products, which may contain these commodities as ingredients. In the case of the fruit-based soft drinks industry, there are no clear regulations, relating to pesticides, which address them, even when there is significant consumption in vulnerable groups such as children. In this work, we have developed a screening method to search automatically for up to 100 pesticides in fruit-based soft drinks extracts based on the application of liquid chromatography-electrospray time-of-flight mass spectrometry (LC-TOF MS). The sample extracts injected were obtained by a preliminary sample treatment step based on solid-phase extraction using hydrophilic-lipophilic balanced polymer-based reverse phase cartridges and methanol as eluting solvent. Subsequent identification, confirmation, and quantitation were carried out by LC-TOF MS analysis: the confirmation of the target species was based on retention time matching and accurate mass measurements of protonated molecules ([M + H]+) and fragment ions (obtaining accuracy errors typically lower than 2 ppm). With the proposed method, we measured over 100 fruit-based soft drink samples, purchased from 15 different countries from companies with brands distributed worldwide and found relatively large concentration levels of pesticides in most of the samples analyzed. The concentration levels detected were of the micrograms per liter level, low when considering the European maximum residue levels (MRLs) set for fruits but very high (i.e., 300 times) when considering the MRLs for drinking or bottled water. The detected pesticides (carbendazim, thiabendazole, imazalil and its main degradate, prochloraz and its main degradate, malathion, and iprodione) are mainly those applied to crops in the final stages of production (postharvest treatment), some of them contain chlorine atoms in their structures. Therefore, steps should be taken with the aim of removing any traces of pesticides in these products, in order to avoid this source of pesticide exposure on the consumer, particularly on vulnerable groups with higher exposure, such as children. PMID:19551973

García-Reyes, Juan F; Gilbert-López, Bienvenida; Molina-Díaz, Antonio; Fernández-Alba, Amadeo R

2008-12-01

359

The degradation of strong basic anion exchange resins and mixed-bed ion-exchange resins: Effect of degradation products on radionuclide speciation  

Microsoft Academic Search

The most important water-soluble products of the radiolytic degradation of anion exchange resins in a cementitious environment are ammonia and methylamines. These ligands do not form complexes with most radionuclides. Exceptions are Ni, Ag, and Pd, which form strong complexes with amines. Other degradation products of anion and mixed-bed ion-exchange resins are of no importance concerning the complexation of trivalent

L. R. van Loon; W. Hummel

1999-01-01

360

Spatial modeling of personalized exposure dynamics: the case of pesticide use in small-scale agricultural production landscapes of the developing world  

PubMed Central

Background Pesticide poisoning is a global health issue with the largest impacts in the developing countries where residential and small-scale agricultural areas are often integrated and pesticides sprayed manually. To reduce health risks from pesticide exposure approaches for personalized exposure assessment (PEA) are needed. We present a conceptual framework to develop a spatial individual-based model (IBM) prototype for assessing potential exposure of farm-workers conducting small-scale agricultural production, which accounts for a considerable portion of global food crop production. Our approach accounts for dynamics in the contaminant distributions in the environment, as well as patterns of movement and activities performed on an individual level under different safety scenarios. We demonstrate a first prototype using data from a study area in a rural part of Colombia, South America. Results Different safety scenarios of PEA were run by including weighting schemes for activities performed under different safety conditions. We examined the sensitivity of individual exposure estimates to varying patterns of pesticide application and varying individual patterns of movement. This resulted in a considerable variation in estimates of magnitude, frequency and duration of exposure over the model runs for each individual as well as between individuals. These findings indicate the influence of patterns of pesticide application, individual spatial patterns of movement as well as safety conditions on personalized exposure in the agricultural production landscape that is the focus of our research. Conclusion This approach represents a conceptual framework for developing individual based models to carry out PEA in small-scale agricultural settings in the developing world based on individual patterns of movement, safety conditions, and dynamic contaminant distributions. The results of our analysis indicate our prototype model is sufficiently sensitive to differentiate and quantify the influence of individual patterns of movement and decision-based pesticide management activities on potential exposure. This approach represents a framework for further understanding the contribution of agricultural pesticide use to exposure in the small-scale agricultural production landscape of many developing countries, and could be useful to evaluate public health intervention strategies to reduce risks to farm-workers and their families. Further research is needed to fully develop an operational version of the model.

Leyk, Stefan; Binder, Claudia R; Nuckols, John R

2009-01-01

361

Modification of Water-Soluble Coal-Derived Products by Dibenzothiophene-Degrading Microorganisms  

PubMed Central

To study mechanisms by which microorganisms oxidize thiophenic sulfur in coal, we tested bacterial cultures for the ability to degrade dibenzothiophene (DBT), DBT-5-oxide, and DBT-sulfone and to modify water-soluble coal products derived from Illinois no. 6 and Ugljevik coals. In yeast extract medium, the majority of selected isolates degraded DBT and accumulated DBT-5-oxide in culture fluids; all but one of the cultures degraded DBT-5-oxide, and none of them degraded DBT-sulfone. Elemental analysis data indicated that the microbial cultures were able to decrease the amount of sulfur in soluble coal products derived from Illinois no. 6 and Ugljevik coals. However, these data suggested that microbially mediated sulfur removal from soluble Ugljevik coal occurred by nonspecific mechanisms. That is, extensive degradation of the carbon structure was concurrent with the loss of sulfur. This conclusion was supported by X-ray photoelectron spectroscopic data which indicated that the reduced sulfur forms in the soluble Ugljevik coal product was not oxidized by microbial treatment.

Stoner, D. L.; Wey, J. E.; Barrett, K. B.; Jolley, J. G.; Wright, R. B.; Dugan, P. R.

1990-01-01

362

Nonphosphate Degradation Products of Tributyl Phosphate and Their Reactivities in Purex Media Under Extreme Conditions  

SciTech Connect

The chemical degradation of tributyl phosphate (TBP) in liquid systems, where TBP was in contact with aqueous solutions containing nitric acid and/or uranyl nitrate, was studied experimentally to clarify the mechanisms of the formation and successive reactions of nonphosphate products under atmospheric pressure. Butyl nitrate, propionic acid, acetic acid, butric acid, and butyl alcohol were formed as the nonphosphate butyl products derived from the butyl-groups of TBP in an open system. The total amount of these products almost equals the amount of the major intermediate phosphate products reduced, i.e., di- and monobutyl phosphates and phosphoric acid. Butyl alcohol was found to be the precursor of the other nonphosphate products.Even when the extremely degraded solvent was further contacted with 10 M nitric acid at 90 deg. C, no significant heat evolution was observed at atmospheric pressure. Only butyl alcohol changed into carboxylic acids by exothermic oxidative reactions.

Tashiro, Yoshikazu [Sumitomo Metal Mining Company, Ltd. (Japan); Kodama, Ryuji [Sumitomo Metal Mining Company, Ltd. (Japan); Sugai, Hiroshi [Sumitomo Metal Mining Company, Ltd. (Japan); Suzuki, Katsuhiko [Japan Nuclear Fuel, Ltd. (Japan); Matsuoka, Shingo [Japan Nuclear Fuel, Ltd. (Japan)

2000-01-15

363

Identification, characterization and cytotoxicity in vitro assay of nitazoxanide major degradation product.  

PubMed

Stress studies of the broad-spectrum antiparasitic nitazoxanide were conducted in order to isolate and elucidate the major degradation product involved in thermal, acid, alkaline, oxidative and photolytic decomposition of the drug in solution and solid state. The major degradation product was identified and characterized using techniques namely LC-DAD, (1)H NMR, (13)C NMR, IR, and MS/MS. The stability of nitazoxanide raw material and nitazoxanide in tablets and in suspension powder was studied under different conditions and the results suggest the formation of the same deacetylated degradation product occur in all cases. This product was also studied in order to determine the preliminary cytotoxicity in vitro with mononuclear cells. Compared with nitazoxanide, the degradation product showed a higher cytotoxicity at a concentration of 40 ?g mL(-1) after 48 h of incubation, under tested conditions. Therefore, stress studies showed that special care must be taken during the preparation, manufacture, and storage of this pharmaceutical drug. PMID:22483900

Malesuik, Marcelo Donadel; Gonçalves, Heloísa Mazotti Lopes; Garcia, Cássia Virginia; Trein, Márcia Rodrigues; Nardi, Nance Beyer; Schapoval, Elfrides Eva Scherman; Steppe, Martin

2012-02-23

364

Evaluation of the pesticide contamination of groundwater sampled over two years from a vulnerable zone in Portugal.  

PubMed

A monitoring program of pesticides was implemented in the "ZV1" vulnerable zone (Directive 91/676/EEC) in Portugal, in order to assess the impact of intensive horticulture practices on groundwater contamination. The monitoring network comprised 23 sampling points sampled every 3 months during a 2-year period. Forty-two pesticides belonging to varied chemical families, including current pesticides, persistent organic pollutants (POPs), and degradation products, were analyzed by solid-phase microextraction (SPME) and gas chromatography with electron-capture detection-thermoionic specific detection (GC-ECD-TSD) or mass spectrometry (GC-MS). Statistical treatment was performed by descriptive analysis followed by chemometric multivariate analysis. The latter included cluster analysis, linear discriminant analysis, and factor analysis. Twenty-two pesticides were quantitated, 20 pesticides were not detected, and metalaxyl, benalaxyl, quinalphos, pirimicarb, and prometryn were only qualitatively detected. The most frequently detected pesticides (% of samples analyzed) were lindane (53%), pendimethalin (49%), endosulfan sulfate (44%), and endosulfan (38%) while those that most frequently exceeded the 0.1 mug L-1 European Union (EU) limit were pendimethalin (13%), endosulfan (12%), endosulfan sulfate (11%), and atrazine (9%). 45% of the samples exceeded the EU limit for individual pesticides while 27% exceeded the limit set to the sum of pesticides (0.5 mug L-1). Principal component analysis revealed five principal components that were attributed to environmental/agrochemical managing factors. The broad range of pesticides investigated combined with the intensive character of the local agriculture contributed to the diversity of pesticides that were detected. However, the frequency of pesticides above the EU regulatory limit is comparable to that found in the literature concerning different Portuguese and European regions. PMID:17608425

Gonçalves, Carlos M; Silva, Joaquim C G Esteves da; Alpendurada, Maria F

2007-07-03

365

Isolation and structure elucidation of degradation products in the potential anticancer drug PAC-1.  

PubMed

PAC-1 was subjected to acid degradation conditions at 80 degrees C for 10h. Four unknown degradation products were isolated from PAC-1 by semi-preparative high performance liquid chromatography using isocratic elution conditions. Based on the ESI-MS and NMR spectral data the structures of these four degradation products were characterized as 2-allyl-6-((E)-((E)-(2-hydroxy-3-(2-hydroxypropyl)benzylidene)hydrazono)methyl)phenol, 2-hydroxy-3-(2-propenyl)-[[2-hydroxy-3-(2-propenyl)phenyl]methylene]hydrazone, 6,6'-(1E,1'E)-hydrazine-1,2-diylidenebis(methan-1-yl-1-ylidene)bis(2-(2-hydroxypropyl)phenol) and 2-hydroxy-3-(2-hydroxypropyl)benzaldehyde. PMID:19889506

Song, Zhen; Chen, Xiaohui; Zhang, Di; Gong, Ping; Bi, Kaishun

2009-10-13

366

Degradation of trichloronitromethane by iron water main corrosion products.  

PubMed

Halogenated disinfection byproducts (DBPs) may undergo reduction reactions at the corroded pipe wall in drinking water distribution systems consisting of cast or ductile iron pipe. Iron pipe corrosion products were obtained from several locations within two drinking water distribution systems. Crystalline-phase composition of freeze-dried corrosion solids was analyzed using X-ray diffraction, and ferrous and ferric iron contents were determined via multiple extraction methods. Batch experiments demonstrated that trichloronitromethane (TCNM), a non-regulated DBP, is rapidly reduced in the presence of pipe corrosion solids and that dissolved oxygen (DO) slows the reaction. The water-soluble iron content of the pipe solids is the best predictor of TCNM reaction rate constant. These results indicate that highly reactive DBPs that are able to compete with oxygen and residual disinfectant for ferrous iron may be attenuated via abiotic reduction in drinking water distribution systems. PMID:18207489

Lee, Jeong-Yub; Pearson, Carrie R; Hozalski, Raymond M; Arnold, William A

2007-12-23

367

Applying pesticides  

NSDL National Science Digital Library

Fertilizer is one way to provide crops with the nutrients they need. Pesticides can also be applied to crops to keep them healthy and free of insects. However, applying too much fertilizer or pesticide protection could harm the environment and organisms.

Scott Bauer (USDA-ARS;Yakima Agricultural Research Laboratory)

2006-05-23

368

Analysis of atrazine and four degradation products in the pore water of the vadose zone, central Indiana  

USGS Publications Warehouse

A new method is described for the analysis of atrazine and four of its degradation products (desethylatrazine, deisopropylatrazine, didealkylatrazine, and hydroxyatrazine) in water. This method uses solid- phase extraction on a graphitized carbon black cartridge, derivatization of the eluate with N-methyl-N-(tert-butyldimethylsilyl)trifluoroacetamide (MTBSTFA), and analysis by gas chromatography/mass spectrometry (GC/MS). This method was used to analyze lysimeter samples collected from a field in central Indiana in 1994 and 1995. Atrazine and its degradation products were transported rapidly through the vadose zone. Maximum values of atrazine ranged from 2.61 to 8.44 ??g/L and occurred from 15 to 57 days after application. Maximum concentrations of the degradation products occurred from 11 to 140 days after atrazine application. The degradation products were more persistent than atrazine in pore water. Desethylatrazine was the dominant degradation product detected in the first year, and didealkylatrazine was the dominant degradation product detected in the second year. Concentrations of atrazine and the degradation products sorbed onto soil were estimated; maximum concentrations ranged from 7.3 to 24 ??g/kg for atrazine and were less than 5 ??g/kg for all degradation products. Degradation of atrazine and transport of all five compounds were simulated by the vadose zone flow model LEACHM. LEACHM was run as a Darcian-flow model and as a non-Darcian-flow model.

Panshin, S. Y.; Carter, D. S.; Bayless, E. R.

2000-01-01

369

Pesticides' influence on wine fermentation.  

PubMed

Wine quality strongly depends on the grape quality. To obtain high-quality wines, it is necessary to process healthy grapes at the correct ripeness stage and for this reason the farmer has to be especially careful in the prevention of parasite attacks on the grapevine. The most common fungal diseases affecting grape quality are downy and powdery mildew (Plasmopara viticola and Uncinula necator), and gray mold (Botrytis cinerea). On the other hand, the most dangerous insects are the grape moth (Lobesia botrana), vine mealybug (Planococcus ficus), and the citrus mealybug (Planococcus citri). Farmers fight grape diseases and insects applying pesticides that can be found at harvest time on grapes. The persistence of pesticides depends on the chemical characteristic of the active ingredients as well as on photodegradation, thermodegradation, codistillation, and enzymatic degradation. The pesticide residues on grapes can be transferred to the must and this can influence the selection and development of yeast strains. Moreover, yeasts can also influence the levels of the pesticides in the wine by reducing or adsorbing them on lees. During the fermentative process, yeasts can cause the disappearance of pesticide residues by degradation or absorption at the end of the fermentation when yeasts are deposited as lees. In this chapter, we reviewed the effect of commonly used herbicides, insecticides, and fungicides on yeasts. We also studied the effect of alcoholic and malolactic fermentation on pesticide residues. PMID:20610173

Caboni, Pierluigi; Cabras, Paolo

2010-06-24

370

EXPOSURE TO PAINT DEGRADATION PRODUCTS WHEN WELDING, FLAME CUTTING, OR STRAIGHTENING PAINTED STEEL  

Microsoft Academic Search

Welding or flame cutting of coated steel gives rise to organic contaminants in addition to inorganic fumes and gases. The exposure of metal workers to paint degradation products was studied by measuring the concentrations of characteristic pollutants in the breathing zone during welding, flame cutting, and straightening painted steel in Finnish shipyards. The sampling was done using an XAD-2 adsorption

Berndt Engström; Maj-Len Henriks-Eckerman; Eeva Ånäs

1990-01-01

371

STRATEGIES FOR THE OPTIMUM SEPARATION OF GAMMA RADIOLYTIC DEGRADATION PRODUCTS OF METHOXYCHLOR USING RP-HPLC  

Microsoft Academic Search

Different types of reversed phase (RP) columns have been incorporated for the separation of gamma radiolytic degradation products (DPs) of methoxychlor. The effect of carbon chain length, carbon content, surface area, pore size, pore volume, and column dimensions of RP columns on DPs separation has also been investigated. The separation of DPs has been optimized employing methanol-water mobile phase and

S. Bilal Butt; M. Riaz

2012-01-01

372

Effects of Water Soluble Extract and Bacterial Degradation Products of Diesel Oil on Marine Phytoplankton  

Microsoft Academic Search

The primary objective of this research was to provide information on the relative toxicity of diesel oil (No. 2 fuel oil) and the microbial degradation products of this fuel on marine phytoplankton. These organisms comprise an essential element of the marine food web. An assessment o f the effects of oil pollution on the growth and photosynthesis of marine phytoplankton

Ching-Hwa Huang

1974-01-01

373

Rhodococcus sp. F92 immobilized on polyurethane foam shows ability to degrade various petroleum products.  

PubMed

This work reports on the immobilization and performance of a hydrocarbon-degrading microorganism on polyurethane foam (PUF) in the bioremediation of petroleum hydrocarbons. The ability of four different microorganisms to immobilize on PUF and to degrade various petroleum products (Arabian light crude (ALC), Al-Shaheen crude (ASC), diesel and oil slops) was assessed by measuring the n-alkane fraction remaining in the petroleum products over time. A Rhodococcus sp. (designated as F92) had the highest number of immobilized viable cells (10(9) cells per cm3 PUF) and a maximum attachment efficiency of 90% on PUF of a density of 14 kg/m3. Scanning electron microscopy showed the presence of extracellular structures that could play an important role in the immobilization of F92 on PUF. Analysis by GC-MS revealed that both free and immobilized F92 cells were able to degrade approximately 90% of the total n-alkanes in the petroleum products tested within 1 week at 30 degrees C. Rhodococcus sp. F92 was efficiently immobilized onto PUF and the immobilized cells were able to degrade a variety of petroleum products such as ALC, ASC, diesel and oil slops. The results suggest the potential of using PUF-immobilized Rhodococcus sp. F92 to bioremediate petroleum hydrocarbons in an open marine environment. PMID:16154500

Quek, Eugene; Ting, Yen-Peng; Tan, Hai Meng

2005-04-12

374

Thermal degradation of municipal plastic waste for production of fuel-like hydrocarbons  

Microsoft Academic Search

Fuel-like utilization is one way of chemical recycling of liquids from waste polymers. The degradation of different mixtures of the most frequently occurring waste polymers (polyethylene, polypropylene, polystyrene, polyamide, ethylene-propylene copolymer and polyurethane rubber) was investigated in a horizontal tube reactor. The effects of cracking temperature and residence time on the yields and structure of the products were studied. The

N. Miskolczi; L. Bartha; G. Deák; B. Jóver

2004-01-01

375

Metabolic labeling of RNA uncovers principles of RNA production and degradation dynamics in mammalian cells  

Microsoft Academic Search

Cellular RNA levels are determined by the interplay of RNA production, processing and degradation. However, because most studies of RNA regulation do not distinguish the separate contributions of these processes, little is known about how they are temporally integrated. Here we combine metabolic labeling of RNA at high temporal resolution with advanced RNA quantification and computational modeling to estimate RNA

Michal Rabani; Joshua Z Levin; Lin Fan; Xian Adiconis; Raktima Raychowdhury; Manuel Garber; Andreas Gnirke; Chad Nusbaum; Nir Hacohen; Nir Friedman; Ido Amit; Aviv Regev

2011-01-01

376

Liquid chromatographic assay of diatrizoic acid and its diiodo degradation products in radio-opaque solutions  

SciTech Connect

A liquid chromatographic method is described for the analysis of diatrizoic acid (2,4,6-triiodo-3,5-diacetamidobenzoic acid) and its 2,4- and 2,6-diiodo degradation products in radio-opaque injection solutions. The method is accurate, precise, and linear at a concentration range of 5-50 ppm. 12 refs., 6 figs., 5 tabs.

Farag, S.A. [Food and Drug Administration, St. Louis, MO (United States)

1995-03-01

377

Significance of the Quantitative Determination of 'Fibrin Degradation Products' in Renal Diseases.  

National Technical Information Service (NTIS)

For 2 years the immunohemagglutination inhibition test, using glutaraldehyde-treated human 'O' red blood cells as the carrier of antigen (fibrinogen), has been done to determine the fibrin and/or fibrinogen degradation products (FDP) in the blood and urin...

1980-01-01

378

Detecting and quantifying lewisite degradation products in environmental samples using arsenic speciation  

SciTech Connect

This report describes a unique method for identifying and quantifying lewisite degradation products using arsenic (III) and arsenic (IV) speciation in solids and in solutions. Gas chromatographic methods, as well as high-performance liquid chromatographic methods are described for separation of arsenic species. Inductively coupled plasma-mass spectrographic methods are presented for the detection of arsenic.

Bass, D.A.; Yaeger, J.S.; Kiely, J.T.; Crain, J.S.; Shem, L.M.; O`Neill, H.J.; Gowdy, M.J. [Argonne National Lab., IL (United States); Besmer, M.; Mohrman, G.B. [Rocky Mountain Arsenal, Commerce City, CO (United States)

1995-12-31

379

The effect of insecticides on growth, germination and cuticle degrading enzyme production by Isaria fumosorosea  

Microsoft Academic Search

The influence of six chemical insecticides on growth, sporulation, conidial germination and cuticle degrading enzyme production by Isaria fumosorosea were investigated under laboratory conditions. Maximum reduction in vegetative growth, sporulation and conidial germination in relation to the control treatment was observed for Chloranthraniliprole whereas Indoxacarb proved to be the safest insecticide causing lowest reduction in these parameters. Chloranthraniliprole, Chlorpyrifos and

Shaukat Ali; Zhen Huang; Shixing Zou; Muhammad Hamid Bashir; Zeqing Wang; Shunxiang Ren

2012-01-01

380

HYDROLOGIC CONDITIONS AFFECTING THE TROPOSPHERIC FLUX OF VINCLOZOLIN AND ITS DEGRADATION PRODUCTS  

EPA Science Inventory

A laboratory chamber was used to determine hydrologic conditions that lead to the tropospheric flux of a suspected anti-androgenic dicarboximide fungicide, vinclozolin (3-(3,5-dichlorophenyl)-5-methyl-5-vinyl-oxzoli-dine-2,4-dione) and three degradation products from sterilized...

381

Analytical methods for environmental sampling of chemical warfare agents and their degradation products  

Microsoft Academic Search

This first technical conference promoted the standardization of analytical procotols to reliably detect chemical warfare agents and their degradation products in soil, water, and other complex environmental media. This supports the various chemical weapons disposal and emergency preparedness programs, Chemical Weapons Convention treaty compliance, installation restoration and base closure decisions. Five major topics were addressed: Implementation for treaty compliance, installation,

A. P. Watson; S. Kistner

1995-01-01

382

Identification of a new degradation product of the antifouling agent Irgarol 1051 in natural samples  

USGS Publications Warehouse

A main degradation product of Irgarol [2-(methylthio)-4-(tert-butylamino)-6-(cyclopropylamino)-s-triazine], one of the most widely used compounds in antifouling paints, was detected at trace levels in seawater and sediment samples collected from several marinas on the Mediterranean coast. This degradation product was identified as 2-methylthio-4-tert-butylamino-s-triazine. The unequivocal identification of this compound in seawater samples was carried out by solid-phase extraction (SPE) coupled on-line with liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry (LC-APCI-MS). SPE was carried out by passing 150 ml of seawater sample through a cartridge containing a polymeric phase (PLRP-s), with recoveries ranging from 92 to 108% (n=5). Using LC-MS detection in positive ion mode, useful structural information was obtained by increasing the fragmentor voltage, thus permitting the unequivocal identification of this compound in natural samples. Method detection limits were in the range of 0.002 to 0.005 ??g/l. Overall, the combination of on-line SPE and LC-APCI-MS represents an important advance in environmental analysis of herbicide degradation products in seawater, since it demonstrates that trace amounts of new polar metabolites may be determined rapidly. This paper reports the LC-MS identification of the main degradation product of Irgarol in seawater and sediment samples. ?? 2001 Elsevier Science B.V. All rights reserved.

Ferrer, I.; Barcelo, D.

2001-01-01

383

Reduction of hazardous organic solvent in sample preparation for hydrophilic pesticide residues in agricultural products with conventional liquid chromatography.  

PubMed

An original extraction method using water as an extractant has been established for environmentally friendly sample preparation procedures for hydrophilic pesticides (acetamiprid, clothianidin, dinotefuran, flonicamid, imidacloprid, methomyl, pymetrozine, thiacloprid, and thiamethoxam) in agricultural samples with conventional HPLC. Water-based extraction and cleanup with two solid-phase extraction cartridges can recover target hydrophilic pesticides quantitatively. The matrix effects of tested samples on the proposed method developed herein were negligibly small. Under the optimized conditions, the recoveries of almost all tested pesticides were 70-120% with satisfactory precision (%CV < 20%). The analytical data are in good accordance with Japanese or European Union guidelines for pesticide residue analysis. The reduction rate of hazardous organic solvents used for the proposed method and by reducing the sample size for extraction was about 70% compared with the Japanese authorized reference method used in this work. The results demonstrate the feasibility of the proposed sample preparation procedures for hydrophilic pesticides. PMID:23614723

Watanabe, Eiki; Kobara, Yuso; Baba, Koji; Eun, Heesoo

2013-05-13

384

Stimulation of aryl metabolite production in the basidiomycete Bjerkandera sp. strain BOS55 with biosynthetic precursors and lignin degradation products  

Microsoft Academic Search

Aryl metabolites are known to have an important role in the ligninolytic system of white rot fungi. The addition of known precursors and aromatic acids representing lignin degradation products stimulated the production of aryl metabolites (veratryl alcohol, veratraldehyde, p-anisaldehyde, and 3-chloro-p-anisaldehyde) in the white rot fungus Bjerkandera sp. strain BOS55. The presence of manganese (Mn) is known to inhibit the

TUNDE MESTER; HENK J. SWARTS; I. Romero; S. Sole; Bont de J. A. M; J. A. Field

1997-01-01

385

78 FR 53139 - Pesticide Product Registration; Receipt of Application for New Uses  

Federal Register 2010, 2011, 2012, 2013

...products containing the insecticide flonicamid, pursuant to the provisions of the...products containing the insecticide, flonicamid (N-(cyanomethyl)-4-(trifluoromethyl...Concord, OH 44077. Active ingredient: Flonicamid. Product Name: Technical...

2013-08-28

386

Superoxide mediated production of hydroxyl radicals by magnetite nanoparticles: demonstration in the degradation of 2-chlorobiphenyl.  

PubMed

Increasing attention has been paid to magnetite nanoparticles (MNPs) due to their highly reductive reactivity toward environmental contaminants. However, there is little information related to the generation of reactive oxygen species (ROS) by MNPs, which in fact plays a vital role for the transformation of contaminants. In this paper, the degradation of 2-chlorobiphenyl (2-CB) by MNPs was investigated. The role of ROS generated by MNPs in this process was elucidated. The results demonstrated that hydroxyl radicals (OH) generated by MNPs at low pH could efficiently degrade 2-CB. The mechanism of the formation of OH by MNPs was divided into two steps: (i) the superoxide radical anion (O2(-)) mediated production of hydrogen peroxide (H2O2), and (ii) the reaction of formed H2O2 with Fe(II) dissolved from MNPs to produce OH through Fenton reaction. Comparison of the degradation products of 2-CB by MNPs with MNPs/ethanol and Fenton reagents further supported the involvement of OH in the degradation of 2-CB. The degradation efficiency of 2-CB by MNPs under acidic conditions was higher than that in alkaline solution. These findings provide a new insight into the understanding of reactivity of MNPs for the transformation of 2-CB and possibly other relevant environmental contaminants. PMID:23434481

Fang, Guo-Dong; Zhou, Dong-Mei; Dionysiou, Dionysios D

2013-01-31

387

78 FR 21945 - Notice of Receipt of Pesticide Products; Registration Applications To Register New Uses  

Federal Register 2010, 2011, 2012, 2013

...Concord, OH 44077. Active ingredient: Flonicamid. Product Type: Insecticide. Proposed Use: Technical Flonicamid Insecticide for Manufacturing and Repacking...Concord, OH 44077. Active ingredient: Flonicamid. Product Type: Insecticide....

2013-04-12

388

Concentrations of selected chlorinated pesticides in shrimp collected from the Calcasieu River/Lake Complex, Louisiana  

SciTech Connect

For several decades inland and coastal aquatic ecosystems have been affected by a multitude of synthetic chemical substances. This is a consequence of population growth and increased industrial and agricultural activity. Many of these chemicals, the by-products of their production, and degradation products ultimately find their way into the aquatic environment as pollutants. The extent to which these pollutants affect the environment and its inhabitants depends largely upon the quantity and nature of the particular compounds involved. Halogenated hydrocarbons, particularly polychlorinated biphenyls (PCBs), and the pesticide DDT and its degradation products have received much attention as environmental pollutants. Because of the economic importance of the shrimping industry to southwest Louisiana, the objective of this study was to analyze shrimp collected from the Calcasieu River/Lake Complex for the presence of selected chlorinated pesticides. The presence of these compounds within shrimp tissues would serve as an indicator for the extent of pollution throughout this important estuarine system.

Murray, H.E.; Beck, J.N. (McNeese State Univ., Lake Charles, LA (USA))

1990-05-01

389

A resource recycling technique of hydrogen production from the catalytic degradation of organics in wastewater  

Microsoft Academic Search

A resource recycling technique of hydrogen production from the catalytic degradation of organics in wastewater by aqueous\\u000a phase reforming (APR) has been proposed. It is worthy of noting that this technique may be a potential way for the purification\\u000a of refractory and highly toxic organics in water for hydrogen production. Hazardous organics (such as phenol, aniline, nitrobenzene,\\u000a tetrahydrofuran (THF), toluene,

XiaoNian Li; LingNiao Kong; YiZhi Xiang; YaoMing Ju; XiaoQiong Wu; Feng Feng; JunFeng Yuan; Lei Ma; ChunShan Lu; QunFeng Zhang

2008-01-01

390

Antiglycation and Antioxidant Effect of Carnosine against Glucose Degradation Products in Peritoneal Mesothelial Cells  

Microsoft Academic Search

Background\\/Aim:Toxicity with advanced glycation end products (AGEs) is a major problem in uremic patients. Treatment with peritoneal dialysis (PD) exacerbates AGE formation as a result of bioincompatibility of the conventional peritoneal dialysis fluid (PDF). The presence of glucose degradation products (GDPs) in PDF is the main cause of its bioincompatibility. Carnosine is an endogenous dipeptide with a powerful antiglycation\\/antioxidant activity.

Mohamed-Saiel Saeed Alhamdani; Abdul-Hameed A.-M. Al-Kassir; Fawzi K. H. Abbas; Nidham A. Jaleel; Maha F. Al-Taee

2007-01-01

391

The influence of lignin degradation products on xylose fermentation by Klebsiella pneumoniae  

Microsoft Academic Search

The inhibitory effects of seven closely related lignin degradation products on xylose fermentation by Klebsiella pneumoniae were studied. Compounds were added in varying concentrations. Less heavily substituted phenolics (at concentrations of, 0.1–0.4 g\\/l) were more inhibitory to growth and solvent production than vanillyl or syringyl derivatives. All of the cultures recovered from this inhibition after a prolonged incubation period. When

Nora K. Nishikawa; Roger Sutcliffe; John N. Saddler

1988-01-01

392

Refined methodology for the determination of neonicotinoid pesticides and their metabolites in honey bees and bee products by liquid chromatography-tandem mass spectrometry (LC-MS/MS).  

PubMed

An analytical method was refined for the extraction and determination of neonicotinoid pesticide residues and their metabolites in honey bees and bee products. Samples were extracted with 2% triethylamine (TEA) in acetonitrile (ACN) followed by salting out, solid phase extraction (SPE) cleanup, and detection using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The method was validated in triplicate at three fortification concentrations in each matrix. Good recoveries were observed for most analytes and ranged between 70 and 120% with relative standard deviations between replicates of <20% in most cases. The method limits of detection were 0.2 ng/g for the parent neonicotinoid pesticides and ranged between 0.2 and 15 ng/g for the neonicotinoid metabolites. This refined method provides lower detection limits and improved recovery of neonicotinoids and their metabolites, which will help researchers evaluate subchronic effects of these pesticides, address data gaps related to colony collapse disorder (CCD), and determine the role of pesticides in pollinator decline. PMID:20163114

Kamel, Alaa

2010-05-26

393

Premature Translational Termination Products Are Rapidly Degraded Substrates for MHC Class I Presentation  

PubMed Central

Nearly thirty percent of all newly synthesized polypeptides are targeted for rapid proteasome-mediated degradation. These rapidly degraded polypeptides (RDPs) are a source of antigenic substrates for the MHC class I presentation pathway, allowing for immunosurveillance of newly synthesized proteins by cytotoxic T lymphocytes. Despite the recognized role of RDPs in MHC I presentation, it remains unclear what molecular characteristics distinguish RDPs from their more stable counterparts. It has been proposed that premature translational termination products may constitute a form of RDP; indeed, in prokaryotes translational drop-off products are normal by-products of protein synthesis and are subsequently rapidly degraded. To study the cellular fate of premature termination products, we used the antibiotic puromycin as a means to experimentally manipulate prematurely terminated polypeptide production in human cells. At low concentrations, puromycin enhanced flux into rapidly degraded polypeptide pools, with small polypeptides being markedly more labile then high molecular weight puromycin adducts. Immunoprecipitation experiments using anti-puromycin antisera demonstrated that the majority of peptidyl-puromycins are rapidly degraded in a proteasome-dependent manner. Low concentrations of puromycin increased the recovery of cell surface MHC I-peptide complexes, indicating that prematurely terminated polypeptides can be processed for presentation via the MHC I pathway. In the continued presence of puromycin, however, MHC I export to the cell surface was inhibited, coincident with the accumulation of polyubiquitinated proteins. The time- and dose-dependent effects of puromycin suggest that the pool of peptidyl-puromycin adducts differ in their targeting to various proteolytic pathways that, in turn, differ in the efficiency with which they access the MHC I presentation machinery. These studies highlight the diversity of cellular proteolytic pathways necessary for the metabolism and immunosurveillance of prematurely terminated polypeptides that are, by their nature, highly heterogeneous.

Lacsina, Joshua R.; Marks, Odessa A.; Liu, Xiongfei; Reid, David W.; Jagannathan, Sujatha; Nicchitta, Christopher V.

2012-01-01

394

A validated stability-indicating RP-HPLC method for levofloxacin in the presence of degradation products, its process related impurities and identification of oxidative degradant.  

PubMed

The objective of current study was to develop a validated specific stability indicating reversed-phase liquid chromatographic method for the quantitative determination of levofloxacin as well as its related substances determination in bulk samples, pharmaceutical dosage forms in the presence of degradation products and its process related impurities. Forced degradation studies were performed on bulk sample of levofloxacin as per ICH prescribed stress conditions using acid, base, oxidative, water hydrolysis, thermal stress and photolytic degradation to show the stability indicating power of the method. Significant degradation was observed during oxidative stress and the degradation product formed was identified by LCMS/MS, slight degradation in acidic stress and no degradation was observed in other stress conditions. The chromatographic method was optimized using the samples generated from forced degradation studies and the impurity spiked solution. Good resolution between the peaks corresponds to process related impurities and degradation products from the analyte were achieved on ACE C18 column using the mobile phase consists a mixture of 0.5% (v/v) triethyl amine in sodium dihydrogen orthophosphate dihydrate (25 mM; pH 6.0) and methanol using a simple linear gradient. The detection was carried out at 294 nm. The limit of detection and the limit of quantitation for the levofloxacin and its process related impurities were established. The stressed test solutions were assayed against the qualified working standard of levofloxacin and the mass balance in each case was in between 99.4 and 99.8% indicating that the developed LC method was stability indicating. Validation of the developed LC method was carried out as per ICH requirements. The developed LC method was found to be suitable to check the quality of bulk samples of levofloxacin at the time of batch release and also during its stability studies (long term and accelerated stability). PMID:19632800

Lalitha Devi, M; Chandrasekhar, K B

2009-06-06

395

Sustainable agricultural practices: energy inputs and outputs, pesticide, fertilizer and greenhouse gas management.  

PubMed

The food security issue was addressed by the development of "modern agriculture" in the last century. But food safety issues and environment degradation were the consequences suffered as a result. Climate change has been recognized as the result of release of stored energy in fossil fuel into the atmosphere. Homogeneous crop varieties, machinery, pesticides and fertilizers are the foundation of uniform commodities in modern agriculture. Fossil fuels are used to manufacture fertilizers and pesticides as well as the energy source for agricultural machinery, thus characterizes modern agriculture. Bio-fuel production and the possibility of the agriculture system as a form of energy input are discussed. PMID:19965338

Wang, Yue-Wen

2009-01-01

396

Biodegradation of Leonardite by an alkali-producing bacterial community and characterization of the degraded products.  

PubMed

In this study, three bacterial communities were obtained from 12 Leonardite samples with the aim of identifying a clean, effective, and economic technique for the dissolution of Leonardite, a type of low-grade coal, in the production of humic acid (HA). The biodegradation ability and characteristics of the degraded products of the most effective bacterial community (MCSL-2), which degraded 50% of the Leonardite within 21 days, were further investigated. Analyses of elemental composition, (13)C NMR, and Fourier transform infrared revealed that the contents of C, O, and aliphatic carbon were similar in biodegraded humic acid (bHA) and chemically (alkali) extracted humic acid (cHA). However, the N and carboxyl carbon contents of bHA was higher than that of cHA. Furthermore, a positive correlation was identified between the degradation efficiency and the increasing pH of the culture medium, while increases of manganese peroxidase and esterase activities were also observed. These data demonstrated that both alkali production and enzyme reactions were involved in Leonardite solubilization by MCSL-2, although the former mechanism predominated. No fungus was observed by microscopy. Only four bacterial phylotypes were recognized, and Bacillus licheniformis-related bacteria were identified as the main group in MCSL-2 by analysis of amplified 16S rRNA genes, thus demonstrating that Leonardite degradation ability has a limited distribution in bacteria. Hormone-like bioactivities of bHA were also detected. In this study, a bacterial community capable of Leonardite degradation was identified and the products characterized. These data implicate the use of such bacteria for the exploitation of Leonardite as a biofertilizer. PMID:22075634

Gao, Tong-Guo; Jiang, Feng; Yang, Jin-Shui; Li, Bao-Zhen; Yuan, Hong-Li

2011-11-11

397

(Pesticide chemistry)  

SciTech Connect

This report summarizes a trip by L. W. Barnthouse of the Environmental Sciences Division (ESD), Oak Ridge National Laboratory (ORNL), to Hamburg, Federal Republic of Germany (FRG), where he participated in the 7th International Congress of Pesticide Chemistry. He chaired a workshop on experimental systems for determining effects of pesticides on nontarget organisms and gave an oral presentation at a symposium on pesticide risk assessment. Before returning to the United States, Dr. Barnthouse visited the Netherlands Institute for Sea Research in Texel, the Netherlands.

Barnthouse, L.W.

1990-09-04

398

Studies on the Degradation Products of Paper with and without Pollutants in a Closed Environment. 1. Preliminary Results.  

National Technical Information Service (NTIS)

The authors have developed methods using Mass Spectroscopy, Liquid Chromatography and Gas Chromatography to detect degradation products of rag paper and newsprint in the presence of some common air pollutants. They have searched for products that might th...

E. J. Parks C. M. Guttman K. L. Jewett F. E. Brinckman

1990-01-01

399

Use of liquid chromatography quadrupole time-of-flight mass spectrometry in the elucidation of transformation products and metabolites of pesticides. Diazinon as a case study  

Microsoft Academic Search

Liquid chromatography (LC) coupled to hybrid quadrupole time-of-flight (QTOF) mass spectrometry (MS) is a useful analytical\\u000a tool in the elucidation and confirmation of transformation products (TPs)\\/metabolites of pesticides with a wide range of polarity,\\u000a in both environmental and biological samples. Firstly, the versatility of LC allows the determination of very distinct TPs\\/metabolites\\u000a as chromatographic conditions can be easily changed and

María Ibáñez; Juan V. Sancho; Óscar J. Pozo; Félix Hernández

2006-01-01

400

40 CFR 158.2120 - Microbial pesticides product analysis data requirements table.  

Code of Federal Regulations, 2012 CFR

...Data Requirements Guideline Number Data Requirement All Use Patterns Test Substance MP EP Test Notes Product Chemistry and Composition 885.1100 Product Identity R MP EP -- 885.1200 Manufacturing process R TGAI and...

2012-07-01

401

40 CFR 158.2120 - Microbial pesticides product analysis data requirements table.  

Code of Federal Regulations, 2011 CFR

...Data Requirements Guideline Number Data Requirement All Use Patterns Test Substance MP EP Test Notes Product Chemistry and Composition 885.1100 Product Identity R MP EP -- 885.1200 Manufacturing process R TGAI and...

2011-07-01

402

40 CFR 158.2171 - Experimental use permit microbial pesticides product analysis data requirements table.  

Code of Federal Regulations, 2011 CFR

...Data Requirements Guideline Number Data Requirement All Use Patterns Test Substance MP EP Test Notes Product Chemistry and Composition 885.1100 Product Identity R MP EP -- 885.1200 Manufacturing process R TGAI and...

2011-07-01

403

77 FR 59610 - Flonicamid; Applications To Add New Food Uses on Previously Registered Pesticide Products  

Federal Register 2010, 2011, 2012, 2013

...EPA-HQ-OPP-2011-0985; FRL-9358-5] Flonicamid; Applications To Add New Food Uses...products containing the insecticide, flonicamid, N-(cyanomethyl)-4-(trifluoromethyl...Concord, OH 44077. Active ingredient: Flonicamid. Product Name: Technical...

2012-09-28

404

77 FR 50686 - Pesticide Products; Receipt of Applications To Register New Uses  

Federal Register 2010, 2011, 2012, 2013

...Imazosulfuron. Product Type: Herbicide. Proposed Uses: Melons (cantaloupe, citron melon, muskmelon, watermelon); and vegetables, tuberous...Fluoxastrobin. Product Type: Fungicide. Proposed Uses: Melon, subgroup 9A; and sorghum. Contact:...

2012-08-22

405

78 FR 64937 - Pesticide Products; Registration Applications for New Active Ingredients  

Federal Register 2010, 2011, 2012, 2013

...Moncada (Valencia) Spain. Active ingredient: Bacillus subtilis strain IAB/BS03. Product type: Fungicide. Proposed...Moncada (Valencia) Spain. Active ingredient: Bacillus subtilis strain IAB/BS03. Product type: Fungicide....

2013-10-30

406

Lignin-degrading enzyme production by Bjerkandera adusta immobilized on polyurethane foam.  

PubMed

Production of the lignin-degrading enzymes lignin peroxidase (Lip), manganese peroxidase (MnP), and laccase (Lac) by the white-rot fungus Bjerkandera adusta was investigated experimentally using polyurethane foam (PUF) as a carrier of immobilized fungal mycelia. An immobilized cell culture with a low-nitrogen medium yielded significantly greater LiP, MnP, and Lac activities in comparison with those obtained in a liquid culture. The maximum activities of the three enzymes were 450, 370, and 100 U/ml, respectively, under the following incubation condition: glucose concentration, 20 g/l; temperature, 30 degrees C; pH 4.5. The activities of MnP and Lac were significantly higher than those reported using other incubation methods. Lignin was degraded to the extent of 40% and its decolorization ratio was about 70% at an incubation time of 40 h using lignin-degrading enzymes from B. adusta. Six different isozymes of MnP were synthesized by B. adusta, two of which exhibited high MnP activity. Our preliminary finding that extracellular enzymes from B. adusta are capable of degrading and decoloring lignin makes these enzymes attractive for further research aimed at their large-scale application in lignin depolymerization, pulp biobleaching, and the degradation of toxic pollutants. PMID:16232571

Nakamura, Y; Sungusia, M G; Sawada, T; Kuwahara, M

1999-01-01

407

77 FR 59190 - Halofenozide; Notice of Receipt of Requests To Voluntarily Cancel Pesticide Registrations and...  

Federal Register 2010, 2011, 2012, 2013

...Pesticide Registrations and Terminate All Uses AGENCY: Environmental Protection...voluntarily cancel pesticide registrations of all products containing the pesticide halofenozide. The requests would cancel all technical and end-use...

2012-09-26

408

Method for determination of methyl tert-butyl ether and its degradation products in water  

USGS Publications Warehouse

An analytical method is described that can detect the major alkyl ether compounds that are used as gasoline oxygenates (methyl tert-butyl ether, MTBE; ethyl tert-butyl ether, ETBE; and tert-amyl methyl ether, TAME) and their most characteristic degradation products (tert-butyl alcohol, TBA; tert-butyl formate, TBF; and tert-amyl alcohol, TAA) in water at sub-ppb concentrations. The new method involves gas chromatography (GC) with direct aqueous injection (DAI) onto a polar column via a splitless injector, coupled with detection by mass spectrometry (MS). DAI-GC/MS gives excellent agreement with conventional purge-and-trap methods for MTBE over a wide range of environmentally relevant concentrations. The new method can also give simultaneous identification of polar compounds that might occur as degradation products of gasoline oxygenates, such as TBA, TBF, TAA, methyl acetate, and acetone. When the method was applied to effluent from a column microcosm prepared with core material from an urban site in New Jersey, conversion of MTBE to TBA was observed after a lag period of 35 days. However, to date, analyses of water samples from six field sites using the DAI-GC/MS method have not produced evidence for the expected products of in situ degradation of MTBE.An analytical method is described that can detect the major alkyl ether compounds that are used as gasoline oxygenates (methyl tert-butyl ether, MTBE; ethyl tert-butyl ether, ETBE; and tert-amyl methyl ether, TAME) and their most characteristic degradation products (tert-butyl alcohol, TBA; tert-butyl formate, TBF; and tert-amyl alcohol, TAA) in water at sub-ppb concentrations. The new method involves gas chromatography (GC) with direct aqueous injection (DAI) onto a polar column via a splitless injector, coupled with detection by mass spectrometry (MS). DAI-GC/MS gives excellent agreement with conventional purge-and-trap methods for MTBE over a wide range of environmentally relevant concentrations. The new method can also give simultaneous identification of polar compounds that might occur as degradation products of gasoline oxygenates, such as TBA, TBF, TAA, methyl acetate, and acetone. When the method was applied to effluent from a column microcosm prepared with core material from an urban site in New Jersey, conversion of MTBE to TBA was observed after a lag period of 35 days. However, to date, analyses of water samples from six field sites using the DAI-GC/MS method have not produced evidence for the expected products of in situ degradation of MTBE.

Church, C. D.; Isabelle, L. M.; Pankow, J. F.; Rose, D. L.; Tratnyek, P. G.

1997-01-01

409

Thermal degradation of Fenitrothion: identification and eco-toxicity of decomposition products.  

PubMed

The thermal decomposition of Fenitrothion [phosphorothioic acid O,O-diethyl O-(3-methyl-4-nitrophenyl) ester] was investigated. Results obtained by different scale calorimetric techniques show that the thermal decomposition of Fenitrothion involves two main steps. Intermediate and final thermal degradation products formed during isothermal and adiabatic thermal decomposition experiments were identified. The eco-toxicological profile of the decomposition products was assessed experimentally and compared to results obtained with a predictive software (ECOSAR). A specific index was defined to assess the change in ecotoxicity profile of decomposition products with respect to the original compound. PMID:22138175

Sanchirico, Roberto; Pinto, Gabriele; Pollio, Antonino; Cordella, Mauro; Cozzani, Valerio

2011-11-17

410

Determination of penicillin G and its degradation products in a penicillin production wastewater treatment plant and the receiving river.  

PubMed

To investigate the fate of penicillin G (PEN G) in the wastewater from a PEN G production facility and the receiving river, an analytical method was developed for the simultaneous detection of PEN G and five degradation products using liquid chromatography-electrospray ionization mass spectrometry (LC-ESI/MS). PEN G had already undergone transformation before entering into the wastewater treatment plant (WWTP), with concentrations of 153+/-4 microg/L in raw wastewater. Most of the PEN G could be eliminated following successive treatments of anaerobic, hydrolysis, and two aerobic units under a hydraulic residence time (HRT) of 30 h, and the final concentrations were 1.68+/-0.48 microg/L in treated water. In the receiving river, the concentration of PEN G decreased from 0.31+/-0.04 microg/L at the discharging point to under the detection limit (0.03 microg/L) at the last sampling site (about 30 km from the discharging point). The main PEN G degradation products in surface water were found to be penilloic acid, penicilloic acid and isopenillic acid, which occupied 65.8%, 20.4% and 12.9%, respectively, of the total concentration at the last site. This is the first study on the behaviors of PEN G and its main degradation products in wastewater treatment processes and the aquatic environment. PMID:17675133

Li, Dong; Yang, Min; Hu, Jianying; Zhang, Yu; Chang, Hong; Jin, Fen

2007-07-20

411

Characterization of stress degradation products of benazepril by using sophisticated hyphenated techniques.  

PubMed

Benazepril, an anti-hypertensive drug, was subjected to forced degradation studies. The drug was unstable under hydrolytic conditions, yielding benazeprilat, which is a known major degradation product (DP) and an active metabolite. It also underwent photochemical degradation in acid and neutral pH conditions, resulting in multiple minor DPs. The products were separated on a reversed phase (C18) column in a gradient mode, and subjected to LC-MS and LC-NMR studies. Initially, comprehensive mass fragmentation pathway of the drug was established through support of high resolution mass spectrometric (HR-MS) and multi stage tandem mass spectrometric (MS(n)) data. The DPs were also subjected to LC-MS/TOF studies to obtain their accurate masses. Along with, on-line H/D exchange data were obtained to ascertain the number of exchangeable hydrogens in each molecule. LC-(1)H NMR and LC-2DNMR data were additionally acquired in a fraction loop mode. The whole information was successfully employed for the characterization of all the DPs. A complete degradation pathway of the drug was also established. PMID:23237710

Narayanam, Mallikarjun; Sahu, Archana; Singh, Saranjit

2012-11-27

412

Fate of CL-20 in sandy soils: degradation products as potential markers of natural attenuation.  

PubMed

Hexanitrohexaazaisowurtzitane (CL-20) is an emerging explosive that may replace the currently used explosives such as RDX and HMX, but little is known about its fate in soil. The present study was conducted to determine degradation products of CL-20 in two sandy soils under abiotic and biotic anaerobic conditions. Biotic degradation was prevalent in the slightly acidic VT soil, which contained a greater organic C content, while the slightly alkaline SAC soil favored hydrolysis. CL-20 degradation was accompanied by the formation of formate, glyoxal, nitrite, ammonium, and nitrous oxide. Biotic degradation of CL-20 occurred through the formation of its denitrohydrogenated derivative (m/z 393 Da) while hydrolysis occurred through the formation of a ring cleavage product (m/z 156 Da) that was tentatively identified as CH(2)=N-C(=N-NO(2))-CH=N-CHO or its isomer N(NO(2))=CH-CH=N-CO-CH=NH. Due to their chemical specificity, these two intermediates may be considered as markers of in situ attenuation of CL-20 in soil. PMID:18801604

Monteil-Rivera, Fanny; Halasz, Annamaria; Manno, Dominic; Kuperman, Roman G; Thiboutot, Sonia; Ampleman, Guy; Hawari, Jalal

2008-09-17

413

Stress Degradation Behavior of Atorvastatin Calcium and Development of a Suitable Stability-Indicating LC Method for the Determination of Atorvastatin, its Related Impurities, and its Degradation Products  

PubMed Central

A rapid, reversed-phase liquid chromatographic method was developed for the quantitative determination of Atorvastatin calcium, its related substances (12 impurities), and degradation impurities in bulk drugs. The chromatographic separation was achieved on a Zorbax Bonus-RP column by employing a gradient elution with water–acetonitrile–trifluoroacetic acid as the mobile phase in a shorter run time of 25 min. The flow rate was 1.0 mL/min and the detection wavelength was 245 nm. The drug substance was subjected to stress studies such as hydrolysis, oxidation, photolysis, and thermal degradation, and considerable degradation was observed in acidic hydrolysis, oxidative, thermal, and photolytic stress conditions. The formed degradation products were reported and were well-resolved from the Atorvastatin and its related substances. The stressed samples were quantified against a qualified reference standard and the mass balance was found to be close to 99.5% (w/w) when the response of the degradant was considered to be equal to the analyte (i.e. Atorvastatin), which demonstrates the stability-indicating capability of the method. The method was validated in agreement with ICH requirements. The method developed here was single and shorter (25 min method for the determination of all 12 related impurities of Atorvastatin and its degradation products), with clearly better resolution and higher sensitivity than the European (85 min method for the determination of six impurities) and United States pharmacopeia (115 min and 55 min, two different methods for the determination of six related substances).

Vukkum, Pallavi; Moses Babu, J.; Muralikrishna, R.

2013-01-01

414

Synergistic collaboration of gut symbionts in Odontotermes formosanus for lignocellulosic degradation and bio-hydrogen production.  

PubMed

In this work, gut microbes from the macrotermitine termite Odontotermes formosanus the cellulolytic Bacillus and fermentative Clostridium were studied in batch experiments using different carbon substrates to bio-mimic the termite gut for hydrogen production. Their fungus comb aging and the in vitro lignocellulosic degradation of the mango tree substrates by the synergistic interaction of Bacillus, Clostridium and Termitomyces were detected by Solid-state NMR. From the results, Bacillus species acted as a mutualist, by initiating an anaerobic environment for the growth of Clostridium, for bio-hydrogen production and the presence of Termitomyces enhanced the lignocellulosic degradation of substrates in vitro and in vivo. Thus, the synergistic collaboration of these three microbes can be used for termite-derived bio-fuel processing technology. PMID:23298769

Mathew, Gincy Marina; Mathew, Dony Chacko; Lo, Shou-Chen; Alexios, Georgy Mathew; Yang, Jia-Cih; Sashikumar, Jagathala Mahalingam; Shaikh, Tanveer Mahamadali; Huang, Chieh-Chen

2012-12-20

415

Fenton and Fenton-like oxidation of pesticide acetamiprid in water samples: Kinetic study of the degradation and optimization using response surface methodology.  

PubMed

The aims of this study were (a) to evaluate the degradation of acetamiprid with the use of Fenton reaction, (b) to investigate the effect of different concentrations of H2O2 and Fe(2+), initial pH and various iron salts, on the degradation of acetamiprid and (c) to apply response surface methodology for the evaluation of degradation kinetics. The kinetic study revealed a two-stage process, described by pseudo- first and second order kinetics. Different H2O2:Fe(2+) molar ratios were examined for their effect on acetamiprid degradation kinetics. The ratio of 3mgL(-1) Fe(2+): 40mgL(-1) H2O2 was found to completely remove acetamiprid at less than 10min. Degradation rate was faster at lower pH, with the optimal value at pH 2.9, while Mohr salt appeared to degrade acetamiprid faster. A central composite design was selected in order to observe the effects of Fe(2+) and H2O2 initial concentration on acetamiprid degradation kinetics. A quadratic model fitted the experimental data, with satisfactory regression and fit. The most significant effect on the degradation of acetamiprid, was induced by ferrous iron concentration followed by H2O2. Optimization, aiming to minimize the applied ferrous concentration and the process time, proposed a ratio of 7.76mgL(-1) Fe(II): 19.78mgL(-1) H2O2. DOC is reduced much more slowly and requires more than 6h of processing for 50% degradation. The use to zero valent iron, demonstrated fast kinetic rates with acetamiprid degradation occurring in 10min and effective DOC removal. PMID:23871596

Mitsika, Elena E; Christophoridis, Christophoros; Fytianos, Konstantinos

2013-07-18

416

Fungicide dissipation and impact on metolachlor aerobic soil degradation and soil microbial dynamics  

Microsoft Academic Search

Pesticides are typically applied as mixtures and or sequentially to soil and plants during crop production. A common scenario is herbicide application at planting followed by sequential fungicide applications post-emergence. Fungicides depending on their spectrum of activity may alter and impact soil microbial communities. Thus there is a potential to impact soil processes responsible for herbicide degradation. This may change

Paul M. White; Thomas L. Potter; Albert K. Culbreath

2010-01-01

417

77 FR 72342 - Notice of Receipt of Pesticide Products; Registration Applications  

Federal Register 2010, 2011, 2012, 2013

...metabolite (5- chloro-4-nitro-1H-pyrazol-3-yl)-methanol (CHNP) at 96.5%. Product type: Plant regulator. Proposed...metabolite (5- chloro-4-nitro-1H-pyrazol-3-yl)-methanol (CHNP) at17%. Product type: Plant regulator...

2012-12-05

418

Toxicity and efficacy of selected pesticides and new acaricides to stored product mites (Acari: Acaridida)  

Technology Transfer Automated Retrieval System (TEKTRAN)

Stored product mites (Acari: Acaridida) can often infest stored products, but currently there is little information regarding efficacy of insecticides or miticides that can be used for control. In this study we evaluated several common insecticides (chlorpyrifos, deltametrhin, beta-cyfluthrin, and a...

419

Photo-assisted electrochemical detection (PAED) following HPLC-UV for the determination of nitro explosives and degradation products  

NASA Astrophysics Data System (ADS)

Continuous efforts implemented by government agencies such as the United States Geological Survey (USGS) aim to manage and protect the integrity of the environment's natural resources. RDX is one of the most frequently utilized nitramine explosives for mining, demolition and munitions purposes in the United States (US). The degradation of RDX in natural environments is of particular importance as a result of the accumulation of consequential degradation products in nature. Specifically, RDX has the potential to be degraded by microorganisms resulting in hazardous levels of harmful degradation products in soil and groundwater. The necessity for the detection of these particular degradation products is emphasized as a consequence of their toxicity as these products are recognized as potential mutagens. Photo-assisted electrochemical detection (PAED) following HPLC-UV is used to develop an analytical method qualified for the assessment of RDX and degradation products. The technique offers unique selectivity possessed by the photochemical reactor coupled to EC detection serving to eliminate the need for repetitive analysis using different column technologies. Furthermore, on-line sample pretreatment is developed and optimized specifically for the preparation of samples consisting of RDX and degradation products. Analytical figures of merit determined for all target analytes using on-line SPE-HPLC-UV-PAED revealed detection limits in the sub part per billion range for RDX and degradation product MEDINA. The effectiveness of the method is exemplified in collaborative studies with the USGS in monitoring the degradation of RDX and formation of degradation products once the nitro explosive is subject to anaerobic microorganisms WBC-2.

Fedorowski, J.; LaCourse, William R.; Lorah, Michelle M.

2012-05-01

420

Determination of terbutaline sulfate and its degradation products in pharmaceutical formulations using LC  

Microsoft Academic Search

There is a lack of information concerning analysis of terbutaline sulfate and quantification of its related substances particularly in the liquid dosage forms. This work aimed at developing and validating an HPLC method for determination of terbutaline sulfate and its possible degradation products, namely, 3,5-dihydroxybenzoic acid, 3,5 dihydroxybenzaldehyde and 1-(3,5-dihydroxyphenyl)-2-[(1,1-dimethylethyl) amino]-ethanone that might appear as impurities in the starting material

N Daraghmeh; M. M Al-Omari; Z Sara; A. A Badwan; A. M. Y Jaber

2002-01-01

421

Liquid chromatographic–mass spectrometric—analyses of anaerobe protein degradation products  

Microsoft Academic Search

A liquid chromatography–electrospray ionisation-mass spectrometry (LC–ESI-MS) method and a liquid chromatography–atmospheric pressure chemical ionisation-mass spectrometry (LC–APCI-MS) method was developed to identify metabolites from the anaerobe protein degradation to biogas. As consequence of a process failure the biogas production breaks down with increasing substrate loading, whereas different metabolites accumulate in the fermentation media. These compounds were identified as metabolites from the

C. Hecht; S. Bieler; C. Griehl

2005-01-01

422

Mechanisms of product formation from the pyrolytic thermal degradation of catechol  

Microsoft Academic Search

Catechol has been identified as one of the most abundant organic products in tobacco smoke and a major molecular precursor for semiquinone type radicals in the combustion of biomass material. The high-temperature gas-phase pyrolysis of catechol under hydrogen-rich and hydrogen-lean conditions was studied using a fused-silica tubular flow reactor coupled to an in-line GC\\/MS analytical system. Thermal degradation of catechol

Slawomir Lomnicki; Hieu Truong; Barry Dellinger

2008-01-01

423

Industrial hygiene evaluation of thermal degradation products from PVC film in meat-wrapping operations  

Microsoft Academic Search

An industrial hygiene evaluation is presented concerning experimental data included in the preceding paper on thermal degradation products from hot-wire and “cool”-rod cutting of PVC film but, in this paper, limited to film used in meat-wrapping operations. Room air concentrations of less than 0.2?ppm HCI and less than 0.05?ppm benzene can be maintained by a number of factors, including minimal

WARREN A. COOK

1980-01-01

424

Degradation products of myelin-oligodendrocyte-associated proteins in a light CNS subcellular fraction  

Microsoft Academic Search

The presence of degradation products of the myelin\\/oligodendrocyte glycoprotein (MOG) and a new myelin\\/oligodendrocyte associated protein, FD1, defined by a monoclonal antibody was established in a subfraction (the floating fraction, or FF) of adult rabbit CNS. The histochemical distribution of FD1 was determined by indirect immunofluorescense using conventional and confocal microscopy. FD1 was found to be present in oligodendrocytes, and

Håkan Persson

1991-01-01

425

Cytotoxicities of ginseng saponins and their degradation products against some cancer cell lines  

Microsoft Academic Search

In order to elucidate the cytotoxicity-structure correlation of ginseng-derived components, several prosapogenins and sapogenins\\u000a were prepared from Korean red ginseng (Panax ginseng) saponins by acid hydrolysis or alkaline cleveage, and their chemical structures were identified by a combination of spectral\\u000a and physical methods. Some of these degradation products showed the cytotoxic activities against various cancer cell lines,\\u000a A549, SK-OV-3, SK-Mel-2,

Nam-In Baek; Dong Seon Kim; You Hui Lee; Jong Dae Park; Chun Bae Lee; Shin Il Kim

1995-01-01

426

Analytical modeling of degradation product partitioning kinetics in source zones containing entrapped DNAPL  

Microsoft Academic Search

Liquid-liquid equilibrium experiments indicate that there is a strong thermodynamic driving force for the reversible sequestration of cis-dichloroethene (DCE) within microbially active dense nonaqueous phase liquid (DNAPL) source zones containing chlorinated ethene solvents. Assessment of the importance of degradation product sequestration, however, requires accurate description of the mass transfer kinetics. Partitioning kinetics of cis-DCE were assessed in a series of

C. Andrew Ramsburg; John A. Christ; Scott R. Douglas; Ali Boroumand

2011-01-01

427

Production of an amylase-degrading raw starch by Gibberella pulicaris  

Microsoft Academic Search

An endophytic fungus, Gibberella pulicaris, produced an amylase which degraded raw starches from cereals and other crops including raw potato, sago, tapioca, corn, wheat and rice starch. In each case, glucose was the main product. Among the raw starches used, raw potato starch gave the highest enzyme activity (85 units mg-1 protein) and raw wheat starch the lowest (49 units mg-1 protein).

Yetti Marlida; Nazamid Saari; Son Radu; Fatimah Abu Bakar

2000-01-01

428

Biodegradation of polyurethanes and nanocomposites to non-cytotoxic degradation products  

Microsoft Academic Search

Polyurethanes with controllable biodegradable properties have been considered for biomedical applications. However, the potential toxicity of their biodegraded by-products is still a concern. In this study, biodegradable polyurethanes based on poly(?-caprolactone) (PCL) and\\/or poly(ethylene glycol) as soft segments and biodegradable polyurethanes containing montmorillonite nanoparticles were synthesized and were subjected to in vitro biodegradation for 4 months. The post-degraded polyurethanes and

Gisele Rodrigues da Silva; Armando da Silva-Cunha Jr.; Francine Behar-Cohen; Eliane Ayres; Rodrigo L. Oréfice

2010-01-01

429

Contribution of lactate buffer, glucose and glucose degradation products to peritoneal injury in vivo  

Microsoft Academic Search

Background. Long-term peritoneal dialysis (PD) is associated with the development of functional and structural alterations of the peritoneal membrane. In this study, we investigated the contribution of low pH lactate buffer, high glucose concentration and glucose degradation products to peritoneal injury in a rat peritoneal exposure model. Methods. Rats received daily 10 ml of either heat- sterilized (3.86% glucose, pH

Mohammad Zareie; Liesbeth H. P. Hekking; Angelique G. A. Welten; Bas A. J. Driesprong; Inge L. Schadee-Eestermans; Dirk Faict; Anne Leyssens; Casper G. Schalkwijk; Robert H. J. Beelen; Jacob van den Born

430

Partial Transformation Products as Indicators of Microbial Hydrocarbon Degradation in Soils  

NASA Astrophysics Data System (ADS)

Monitored natural decay (intrinsic bioremediation), a cost-effective method for remediating contaminated property, is widely applied to fuel contaminated sites. If an intrinsic bioremediation approach could be supported for the clean up of polynuclear aromatic hydrocarbon (PAH) contaminated properties, millions of dollars in clean-up costs could potential be saved, especially in transfers of industrial properties that will continue to be used for industrial purposes. Proving intrinsic biodegradation of polynuclear aromatic hydrocarbons (PAHs) is problematic. Slow PAH biodegradation rates in contaminated soils mean that oxygen mass transfer rates into the soil exceeds bacterial oxygen demand. Likewise carbon dioxide production during degradation is sufficiently slow that carbon dioxide will not accumulate in the soil gas to levels exceeding background, uncontaminated soils. Therefore, oxygen depletion and carbon dioxide accumulation, typical indicators of intrinsic remediation activity at fuel contaminated sites, are of little use in demonstrating intrinsic PAH remediation. Additionally, direct measurement of PAH loss over time is of limited use in the absence of extensive historical records, especially at sites that are still emitting PAHs as part of their operations. PAH loss rates may be in the order of 10% per year, whereas combined sampling and analytical error can be greater than 50%. It is our hypothesis that PAH degradation products, such as aromatic carboxylic acids and dihydrodiols, will be present in soils where biodegradation is occurring and absent in soils that are biologically inactive. We have developed methods for the extraction of PAH biodegradation products from soils and the analysis of these metabolites by both gas chromatography and high performance liquid chromatography. We have tested our hypothesis against soils undergoing both active and passive bioremediation. Our results indicate that PAH degradation products are detectable in many soils and that the presence of metabolites is correlated with PAH degradation.

Stringfellow, W. T.

2001-12-01

431

Detection of simulants and degradation products of chemical warfare agents by vibrational spectroscopy  

Microsoft Academic Search

This work was focused in the measurement of spectroscopic signatures of Chemical Warfare Agent Simulants (CWAS) and degradation products of chemical agents using vibrational spectroscopy for the generation of spectroscopic libraries. The chemicals studied were: DMMP, DIMP, 2-CEES, 2-BAET, 1,4-thioxane, thiodiglycol sulfoxide, dihexylamine, cyclohexylamine, among others. Raman microscopy experiments were performed at different excitation wavelengths that spanned from NIR at

Orlando Ruiz-Pesante; Leonardo C. Pacheco-Londoño; Oliva M. Primera-Pedrozo; William Ortiz; Yadira M. Soto-Feliciano; Deborah E. Nieves; Michael L. Ramirez; Samuel P. Hernández-Rivera

2007-01-01

432

Utilization of Ganglioside-Degrading Paenibacillus sp. Strain TS12 for Production of Glucosylceramide  

PubMed Central

Gangliosides, sialic acid-containing glycosphingolipids, are membrane constituents of vertebrates and are known to have important roles in cellular differentiation, adhesion, and recognition. We report here the isolation of a bacterium capable of degrading gangliotetraose-series gangliosides and a new method for the production of glucosylceramide with this bacterium. GM1a ganglioside was found to be sequentially degraded by Paenibacillus sp. strain TS12, which was isolated from soil, as follows: GM1a ? asialo GM1 ? asialo GM2 ? lactosylceramide ? glucosylceramide. TS12 was found to produce a series of ganglioside-degrading enzymes, such as sialidases, ?-galactosidases, and ?-hexosaminidases. TS12 also produced ?-glucosidases, but glucosylceramide was somewhat resistant to the bacterial enzyme under the conditions used. Taking advantage of the specificity, we developed a new method for the production of glucosylceramide using TS12 as a biocatalyst. The method involves the conversion of crude bovine brain gangliosides to glucosylceramide by coculture with TS12 and purification of the product by chromatography with Wakogel C-300 HG.

Sumida, Tomomi; Sueyoshi, Noriyuki; Ito, Makoto

2002-01-01

433

Microbially Mediated Degradation of Common Pharmaceuticals and Personal Care Products in Soil Under Aerobic and Reduced Oxygen Conditions  

Microsoft Academic Search

Biological degradation rates of estrogen compounds and common pharmaceutical and personal care products (PPCPs) were examined\\u000a in soils with a long history of exposure to these compounds through wastewater effluent and in soil not previously exposed.\\u000a Biological degradation rates over 14 days were compared under aerobic and anaerobic conditions. Estrogen compounds including\\u000a estrone, 17?-estradiol, estriol, and 17?-ethinylestradiol exhibited rapid degradation by

Deborah L. Carr; Audra N. Morse; John C. Zak; Todd A. Anderson

2011-01-01

434

77 FR 48519 - Registration Applications for Pesticide Products Containing New Active Ingredients  

Federal Register 2010, 2011, 2012, 2013

...EPA-HQ-OPP-2012-0485. Applicant: Summit Chemical Company, 235 South Kresson Street, Baltimore, MD 21224-2616. Active Ingredient: Bacillus thuringiensis subsp. israelensis, Strain SUM-6218 at 100.0%. Product Type: microbial insecticide. Proposed...

2012-08-14

435

78 FR 55695 - Notice of Receipt of Pesticide Products; Registration Applications To Register New Uses  

Federal Register 2010, 2011, 2012, 2013

...Indianapolis, IN 46268-1054. Active ingredient: 1,3- Dichloropropene. Product Type: Fumigant (Fungicide). Proposed Use: Pineapple. 8. EPA Registration File Symbol/Registration Number: 86203-EA and 86203-1. Docket ID Number:...

2013-09-11

436

78 FR 9389 - Notice of Receipt of Pesticide Products; Registration Applications To Register New Uses  

Federal Register 2010, 2011, 2012, 2013

...13-07H and cucurbit vegetables (crop group 9...Barley, fruiting vegetable group 8-10, citrus...southern pea), fruiting vegetable group 8-10, pome...Forchlorfenuron. Product Type: Plant Growth Regulator....

2013-02-08

437

77 FR 66836 - Notice of Receipt of Pesticide Products; Registration Applications  

Federal Register 2010, 2011, 2012, 2013

...Riverside, CA 92507. Active ingredient: Biochemical Pheromone (Mating Disruptor) with...Riverside, CA 92507. Active ingredient: Biochemical Pheromone (Mating Disruptor) with...11-Dodecatrien-1-ol, formate at 2%. Product Type: Biochemical Pheromone. Proposed Use:...

2012-11-07

438

77 FR 75152 - Notice of Receipt of Pesticide Products; Registration Applications  

Federal Register 2010, 2011, 2012, 2013

...at 5.25%. Product type: Plant Growth Regulator. Proposed use: Fruit color development/color enhancement on red apple varieties. Contact: Gina Burnett, BPPD, (703) 605-0513, email address: burnett.gina@epa.gov. List...

2012-12-19

439

Fate and transport of pesticides in the ground water systems of southwest Georgia, 1993-2005  

USGS Publications Warehouse

Modern agricultural practices in the United States have resulted in nearly unrivaled efficiency and productivity. Unfortunately, there is also the potential for release of these compounds to the environment and consequent adverse affects on wildlife and human populations. Since 1993, the National Water-Quality Assessment (NAWQA) program of the U.S. Geological Survey has evaluated water quality in agricultural areas to address these concerns. The objective of this study is to evaluate trends in pesticide concentrations from 1993-2005 in the surficial and Upper Floridan aquifers of southwest Georgia using pesticide and pesticide degradate data collected for the NAWQA program. There were six compounds - five herbicides and one degradate - that were detected in more than 20% of samples: atrazine, deethylatrazine (DEA), metolachlor, alachlor, floumeturon, and tebuthiuron. Of the 128 wells sampled during the study, only eight wells had pesticide concentrations that either increased (7) or decreased (1) on a decadal time scale. Most of the significant trends were increasing concentrations of pesticides in older water; median pesticide concentrations did not differ between the surficial and Upper Floridan aquifers from 1993 and 2005. Deethylatrazine, in the Upper Floridan aquifer, was the only compound that had a significant change (increase) in concentration during the study. The limited number of wells with increases in pesticide concentrations suggest that ground-water sources of these compounds are not increasing in concentration over the time scale represented in this study. Copyright ?? 2008 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.