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1.
Environmental Science and Pollution Research - Adolescent females are often environmentally exposed to pesticides by living near agricultural fields, by using pesticides at home, or by having...  相似文献   

2.
随着对农药污染认识的深入,农药对生态系统的初级生产者———藻类毒性以及毒性机制的研究不断增多。农药对藻类的毒性在于破坏藻类生物膜的结构和功能、影响藻类的光合作用、改变呼吸作用以及固氮作用,影响藻类的生理进程并改变其生化组分。开展农药对藻类毒性机理的研究,揭示农药结构—活性关系,对农药的研制和应用,评价农药的生态风险,减少农药对藻类的毒害是重要的。在自然环境中还发现藻能富集和降解农药。因此,对于这些藻来说,农药对藻类的毒害作用和藻类对农药的富集和降解作用可能同时存在。本文综述了农药对藻类的毒性机理以及藻类对农药的富集和降解作用。  相似文献   

3.
Environmental Science and Pollution Research - The excessive use of pesticides is posing major threats to humans and the environment. However, the environmental exposure and impact of pesticides in...  相似文献   

4.
Organophosphorus pesticides (OPs) are ubiquitous in the environment and are highly toxic to amphibians. They deactivate cholinesterase, resulting in neurological dysfunction. Most chemicals in this group require oxidative desulfuration to achieve their greatest cholinesterase-inhibiting potencies. Oxon derivatives are formed within liver cells but also by bacterial decay of parental pesticides. This study examines the toxicity of chlorpyrifos, malathion and diazinon and their oxons on the foothill yellow-legged frog (Rana boylii). R. boylii is exposed to agricultural pesticides in the California Central Valley. Median lethal concentrations of the parental forms during a 96 h exposure were 3.00 mg/L (24h) for chlorpyrifos, 2.14 mg/L for malathion and 7.49 mg/L for diazinon. Corresponding oxons were 10 to 100 times more toxic than their parental forms. We conclude that environmental concentrations of these pesticides can be harmful to R. boylii populations.  相似文献   

5.
Abstract

This report discusses the responsibilities of government for the legislation of pesticides, and describes the impact of various statutes on the use of pesticides in agriculture. Governmental responsibilities for management of the economy, education, and enactment of laws and regulations are discussed, and the history of U.S. legislation of pesticides and related substances is presented. Finally, the impact of pesticide regulation on international trade is considered.  相似文献   

6.
Concentrations of selected organochlorine pesticides and PCBs in seven fish species (cichlids) from the north end of the Lake Tanganyika, Burundi, Africa were determined. Results were compared to previous work on the Lake Tanganyika and other water bodies and to the European Community maximum residue levels (MRLs) in edible fat. The analytical method included a hot Soxhlet extraction with a mixture of acetone: hexane (1:3, v/v), gravimetrically lipid determination, and a single step clean-up. For PCBs and stable pesticides, the clean-up was done on activated silica gel impregnated with concentrated sulfuric acid, while for non acid-stable pesticides superposed layers of alumina, silica and florisil impregnated with 15% methanolic solution of KOH were successively used. Recoveries of organochlorine pesticides from certified reference material (CRM 430) were ranging from 86% for p,p'-DDT to 107% for endrin, while recoveries from blank fat spiked fortified at three different levels were between 65% for alachlor at the lowest fortification level and 107% for mirex at the highest fortification level. The limits of detection for each analyte were ranging from 0.1 ng/g to 0.5 ng/g fat. All chlorinated pesticides were found in the analyzed species but at low concentrations. Boulengerochromis microlepis contained the highest concentrations of HCHs (288.2 +/- 15.5 ng/g fat) and DDTs (909.1 +/- 42.5 ng/g fat), while the highest PCB levels (166.7 +/- 37.4 ng/g fat for the sum of 12 congeners) were found in Oreochromis niloticus. However, there is no evidence that Lake Tanganyika is more contaminated with pesticides than other African water bodies.  相似文献   

7.
An analytical method, using supercritical fluid extraction (SFE), was assessed for residue analysis of the insecticides fipronil, acrinathrin and pyridaben and the fungicide kresoxim-methyl in melons. Extraction conditions were optimized on glass beads, as inert material, evaluating different pressures, temperatures, and CO(2) volumes. Also, the extractability of pesticides from hydromatrix and anhydrous magnesium sulfate was evaluated. Both adsorbents were evaluated for the preparation of SFE-spiked melon samples. Extractions of fortified samples were done using 20 mL of CO(2), 300 atm, and 50 degrees C. Different extraction conditions, including the addition of water and methanol as a static modifier, were used to assess the extractability of these pesticides, and the addition of methanol was demonstrated to improve the extraction of all the studied pesticides.  相似文献   

8.
Environmental Science and Pollution Research - The elimination of persistent organic pollutants (POPs) obsolete pesticides stockpiles, particularly the organochlorine pesticides (OCPs), is one of...  相似文献   

9.
An analytical method, using supercritical fluid extraction (SFE), was assessed for residue analysis of the insecticides fipronil, acrinathrin and pyridaben and the fungicide kresoxim-methyl in melons. Extraction conditions were optimized on glass beads, as inert material, evaluating different pressures, temperatures, and CO2 volumes. Also, the extractability of pesticides from hydromatrix and anhydrous magnesium sulfate was evaluated. Both adsorbents were evaluated for the preparation of SFE-spiked melon samples. Extractions of fortified samples were done using 20 mL of CO2, 300 atm, and 50°C. Different extraction conditions, including the addition of water and methanol as a static modifier, were used to assess the extractability of these pesticides, and the addition of methanol was demonstrated to improve the extraction of all the studied pesticides.  相似文献   

10.
Abstract

This research is a case study on detection of pesticides in river water, sediment as well as fish samples from Tapi River, among the major rivers of Gujarat, India. To investigate the misuse, concentration level and occurrence patterns of persistent pesticides, samples were collected from the river. Chlorpyrifos, methyl parathion, hexachlorocyclohexane (HCH), dichloro diphenyl trichloroethane (DDT) and endosulfan were analyzed by gas chromatography technique with flame ionization detector (FID). Scanty reports are available, but after 1999, no such data are reported as some of these pesticides have been banned. Although these pesticides are still in use which we observed from the obtained results. In this river, the amount of endosulfan, chlorpyrifos, and methyl parathion was observed in surface water with concentrations of 37.56?µg/L, 0.86?µg/L and 0.43?µg/L, respectively. Endosulfan, DDT and methyl parathion detected in sediment were 38.38?ng/g, 0.65?ng/g and 0.77?ng/g, respectively. In fish samples, levels of endosulfan, chlorpyrifos, and methyl parathion detected were 101.28, 0.392, and 3.49?ng/g correspondingly. Results showed that highly toxic pesticides are still being used in the surrounding area, and there is an urgent need for enforcement of rules to control the production and application of such pesticides.  相似文献   

11.
A method is described for the determination of organochlorine and organophosphate pesticide residues in fruits, vegetables and sediments. The concentrated solvent extract was sealed in a polymeric membrane tube, dialysed in cyclohexane and the solvent replaced with hexane. The organophosphates were analysed on a specific thermionic detector without further clean-up. For the organochlorine pesticides the extract was eluted through 3 g of alumina and analysed on GC/ECD. The clean-up for sediment extract was carried out on a 10 g alumina column with 100 mL hexane containing 5% acetone and the eluate was concentrated to 5 mL. The detection limit for organophosphates on a 40 g sample and a final volume of 10 mL was on the average 0.01 mg/kg. The detection limit for organochlorine pesticides, with the final volume of 25 mL, was 0.005 mg/kg for all pesticides except for p,p'-DDT and endosulfan sulphate, which was 0.01 mg/kg. The detection limit for organochlorine pesticides in sediment, with the final volume of 2 mL, was less than 1 microgram/kg and for organophosphate pesticides less than 10 micrograms/kg when the final volume was made to 0.5 mL. At the detection limits the method produced a very high coefficient of variation for both organochlorine and organophosphate pesticides.  相似文献   

12.
Abstract

A method is described for the determination of organochlorine and organophosphate pesticide residues in fruits, vegetables and sediments. The concentrated solvent extract was sealed in a polymeric membrane tube, dialysed in cyclohexane and the solvent replaced with hexane. The organophosphates were analysed on a specific thermionic detector without further clean‐up. For the organochlorine pesticides the extract was eluted through 3 g of alumina and analysed on GC/ECD. The clean‐up for sediment extract was carried out on a10 g alumina column with 100 mL hexane containing 5% acetone and the eluate was concentrated to 5 mL.

The detection limit for organophosphates on a 40 g sample and a final volume of 10 mL was on the average 0.01 mg/kg. The detection limit for organochlorine pesticides, with the final volume of 25 mL, was 0.005 mg/kg for all pesticides except for p,p'‐DDT and endosulfan sulphate, which was 0.01 mg/kg.

The detection limit for oganochlorine pesticides in sediment, with the final volume of 2 mL, was less than 1 μg/kg and for organophosphate pesticides less than 10 μg/kg when the final volume was made to 0.5 mL. At the detection limits the method produced a very high coefficient of variation for both organochlorine and organophosphate pesticides.  相似文献   

13.
In this work we evaluate the contamination caused by HCH residues in the soil, leachates, river water and sediments of an industrial estate of the NW of Spain. We study the distribution of the isomers in the different matrices, analysing 37 soil samples, collected in eight points at several depths, six natural leachates, four river water samples and three river sediments. Soil and leachate samples present very high levels of HCH isomers, higher than the established by legislation, and some pesticides were also detected in the analysed river water whereas no pesticides were detected in the river sediments. The distribution of isomers was different depending on the matrix analysed. Some natural degradation products and also other organochlorine pesticides were detected in the samples analysed.  相似文献   

14.
Tonghui River, a typical river in Beijing, People's Republic of China, was studied for its water and sediment quality, by determining the levels of 16 polycyclic aromatic hydrocarbons (PAHs), 12 polychlorinated biphenyls (PCBs) and 18 organochlorine pesticides in water and sediment samples. Total PAHs, PCBs and organochlorine pesticides concentrations in water varied from 192.5 to 2651 ng/l, 31.58-344.9 ng/l and 134.9-3788 ng/l, respectively. The total PAHs, PCBs and organochlorine pesticides concentrations in surficial sediments were 127-928 ng/g, 0.78-8.47 ng/g and 1.79-13.98 ng/g dry weight, respectively. The results showed that the concentration of these selected organic pollutants in sediment was higher than those in surface water. It may be due to the fact that organic hydrophobic pollutants tend to stay in the sediments. The PAHs were dominated by 2-, 3-ring components in water samples and by 3- and 4-ring compounds in sediment. For organochlorines, alpha-HCH, delta-HCH, Heptachlor, Endosulfan II, DDT are the major organochlorine pesticides in water while Heptachlor, Dieldrin and DDE composed of 95% of total organochlorine pesticides in sediment. For HCHs (HCHs=alpha-HCH+beta-HCH+gamma-HCH+delta-HCH), the predominance of alpha-HCH of total HCHs were clearly observed in water and sediment. PCB18, PCB31 and PCB52 were predominant in water, on average these compounds collectively accounted for 67% of total PCBs. But in sediment, the predominant compounds were PCB28, PCB31 and PCB153, which accounted for 71% of total PCBs in sediment. The levels of micro pollutants in our study areas were compared with other studies.  相似文献   

15.
Stanek K  Drobne D  Trebse P 《Chemosphere》2006,64(10):1745-1752
In parallel laboratory experiments, we determined the effect of a typical representative of organophosphorous pesticides, diazinon, on AChE activity, lipid, protein and glycogen content, weight change, feeding activity and mortality of juvenile and adult terrestrial isopods Porcellio scaber (Isopoda, Crustacea). Organophosphorous pesticides (OP) are among the most extensively used pesticides, which have replaced organochlorine pesticides. OPs inhibit the enzyme acetylcholinesterase (AChE), resulting in neurotoxicity. They have more widespread effects on non-target organisms than do organochlorine pesticides. The aim of this study was to link effect of diazinon on target enzyme to energy reserves and to integrated biomarker responses in juvenile and adult P. scaber. The non-observed effect concentration (NOEC) for AChE activity after diazinon exposure in two weeks toxicity study with isopods was below 5 microg/g diazinon. There was a good agreement between concentrations at which AChE and survival were affected (10 microg/g diazinon in juveniles, 100 microg/g diazinon in adults). We revealed a link among AChE activity, protein content and mortality. Glycogen and lipid content, feeding activity and weight change were not affected in two weeks diazinon exposure up to 100 microg/g diazinon. Juveniles were affected at concentrations that were an order of magnitude lower than those provoking similar effects on adults. Recommendations are made for future toxicity studies with terrestrial isopods.  相似文献   

16.
The objective of this study was to evaluate the presence of organochlorine pesticides in samples of forage, soil, water, and milk in four units of an organic production system for cow´s milk (samples of forage, milk, soil, and water) in Tecpatan, Chiapas, Mexico. The organochlorine pesticides were extracted from forage, soil and water based on the USEPA (2005) guideline and from milk based on the IDF 1991 guideline. The pesticides were identified and quantified by gas chromatography with electron capture detector (CG-ECD). In general, the highest average concentration of total pesticides was found in the samples of milk and forage (311 ± 328 and 116.5 ±77 ng g?1 respectively). Although, the production systems analyzed are organic, organochlorine pesticides were detected in all environmental samples (forage, soil, water, and organic milk). Although no values surpassed the defined limits of Mexican and International regulation it is advisable that a monitoring program of contaminants in these production systems is continued.  相似文献   

17.
Abstract

Scientific and regulatory interest in ground water contamination by pesticides increased significantly in 1979. This was prompted by findings of the nematicide 1,2‐dibromo‐3‐chloropropane (DBCP) and the nematicide/insecticide aldicarb (Temik®) in ground water in several states. Since that time, at least 130 pesticides and pesticide metabolites have been detected in ground water in over 150 studies, but detection frequencies are 4–10% nationally. Detection frequencies of pesticides over Health Advisory Levels are generally lower. Screening‐level models and detailed computer simulation models are useful for risk assessments and regulatory decisions. Attenuation Factor, CMLS, PRZM2, GLEAMS, and LEACHM are all useful models.  相似文献   

18.
Earthworms,pesticides and sustainable agriculture: a review   总被引:1,自引:0,他引:1  
The aim of this review is to generate awareness and understand the importance of earthworms in sustainable agriculture and effect of pesticides on their action. The natural resources are finite and highly prone to degradation by the misuse of land and mismanagement of soil. The world is in utter need of a healthy ecosystem that provides with fertile soil, clean water, food and other natural resources. Anthropogenic activities have led to an increased contamination of land. The intensification of industrial and agricultural practices chiefly the utilization of pesticides has in almost every way made our natural resources concave. Earthworms help in a number of tasks that support many ecosystem services that favor agrosystem sustainability but are degraded by exhaustive practices such as the use of pesticides. The present review assesses the response of earthworm toward the pesticides and also evaluates the relationship between earthworm activity and plant growth. We strictly need to refresh and rethink on the policies and norms devised by us on sustainable ecology. In an equivalent way, the natural resources should be utilized and further, essential ways for betterment of present and future livelihood should be sought.  相似文献   

19.
Singh KP  Mohan D  Sinha S  Dalwani R 《Chemosphere》2004,55(2):227-255
Studies were undertaken to assess the impact of wastewater/sludge disposal (metals and pesticides) from sewage treatment plants (STPs) in Jajmau, Kanpur (5 MLD) and Dinapur, Varanasi (80 MLD), on health, agriculture and environmental quality in the receiving/application areas around Kanpur and Varanasi in Uttar Pradesh, India. The raw, treated and mixed treated urban wastewater samples were collected from the inlet and outlet points of the plants during peak (morning and evening) and non-peak (noon) hours. The impact of the treated wastewater toxicants (metals and pesticides) on the environmental quality of the disposal area was assessed in terms of their levels in different media samples viz., water, soil, crops, vegetation, and food grains. The data generated show elevated levels of metals and pesticides in all the environmental media, suggesting a definite adverse impact on the environmental quality of the disposal area. The critical levels of the heavy metals in the soil for agricultural crops are found to be much higher than those observed in the study areas receiving no effluents. The sludge from the STPs has both positive and negative impacts on agriculture as it is loaded with high levels of toxic heavy metals and pesticides, but also enriched with several useful ingredients such as N, P, and K providing fertilizer values. The sludge studied had cadmium, chromium and nickel levels above tolerable levels as prescribed for agricultural and lands application. Bio-monitoring of the metals and pesticides levels in the human blood and urine of the different population groups under study areas was undertaken. All the different approaches indicated a considerable risk and impact of heavy metals and pesticides on human health in the exposed areas receiving the wastewater from the STPs.  相似文献   

20.
Soil column experiments are used to investigate the fate of three pesticides of high, intermediate, and low solubility in groundwater: N- phosphonomethyl glycine (glyphosate); O,O-diethyl-S-[(ethylthio)methyl]phosphorodithioate (phorate); (2,4-dichlorophenoxy)acetic acid (2,4-D). Feed solutions are prepared by adding each pesticide (100 mg/L glyphosate, 50 micro g/L phorate, 50 mg/L 2,4-D) along with conservative tracer, KBr, in synthetic groundwater. The concentration of the pesticides in effluents is detected by ion chromatography (glyphosate, 2,4-D) and GC-FID (phorate). The Br(-) breakthrough curves are employed to estimate the dispersion coefficient and mean pore velocity in each column. Solute transport and reactive models accounting for equilibrium/non-equilibrium sorption and biodegradation are coupled with inverse modeling numerical codes to estimate the kinetic parameters for all pesticides.  相似文献   

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