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1.
Although pesticide regulatory tools are mainly based on individual substances, aquatic ecosystems are usually exposed to multiple pesticides from their use on the variety of crops within the catchment of a river. This study estimated the impact of measured pesticide mixtures in surface waters from 2002 and 2008 within three important Portuguese river basins (‘Mondego’, ‘Sado’ and ‘Tejo’) on primary producers, arthropods and fish by toxic pressure calculation. Species sensitivity distributions (SSDs), in combination with mixture toxicity models, were applied. Considering the differences in the responses of the taxonomic groups as well as in the pesticide exposures that these organisms experience, variable acute multi-substance potentially affected fractions (msPAFs) were obtained. The median msPAF for primary producers and arthropods in surface waters of all river basins exceeded 5%, the cut-off value used in the prospective SSD approach for deriving individual environmental quality standards. A ranking procedure identified various photosystem II inhibiting herbicides, with oxadiazon having the relatively largest toxic effects on primary producers, while the organophosphorus insecticides, chlorfenvinphos and chlorpyrifos, and the organochloride endosulfan had the largest effects on arthropods and fish, respectively. These results ensure compliance with European legislation with regard to ecological risk assessment and management of pesticides in surface waters.  相似文献   

2.
我国区域性水体农药污染现状研究分析   总被引:5,自引:0,他引:5  
以4大流域为基础,较为全面地概述了我国区域性农药污染情况,并对其污染原因进行了分析。结果表明:长江流域有机磷农药、氨基甲酸酯类农药以及部分拟除虫菊酯类农药的的残留量很高;珠江流域农药污染情况较轻,检出量均低于我国地表水环境质量标准;黄淮海流域和松辽流域主要检出农药为酰胺类和三嗪类农药,但具体检出物质存在差异。研究分析表明各流域农药污染与该区域的农作物种类有重要关系。  相似文献   

3.
There is increasing recognition that fine sediment represents an important diffuse source pollutant in surface waters, due to its role in governing the transfer and fate of many substances, including nutrients, heavy metals, pesticides and other organic contaminants, and because of its impacts on aquatic ecology. Catchment management strategies therefore frequently need to include provision for the control of sediment mobilisation and delivery. The sediment budget concept provides a valuable framework for assisting the management and control of diffuse source sediment pollution and associated problems, by identifying the key sources and demonstrating the importance of intermediate stores and the likely impact of upstream mitigation strategies on downstream suspended sediment and sediment-associated contaminant fluxes. Accordingly, the utility of the sediment budget concept for catchment management is further discussed, by introducing examples from several contrasting river basins.  相似文献   

4.
Pesticide pollution of surface waters represents a considerable hazard for the aquatic environment. However, the mean amount of pesticides reaching the water resources varies considerably between regions and depends highly upon application rates, chemical characteristics of pesticides and natural conditions during application. In this study a model was developed which estimates loss of 42 active ingredients applied to 11 field crops, vineyards and orchards along each non-point source path of entry (subsurface drains, runoff and spray drift). A spatially and temporally differentiated data set of application rates and periods was compiled for each active ingredient and target culture to enable the modeling of pesticide transport. The model results are provided in digital raster format (100 m×100 m) within a geographic information system (GIS). The calculated pesticide loads in surface waters were compared with measured loads from different catchments in Germany. Both data sets agreed as to the order of magnitude, nevertheless due to the scale of the study the estimated loads cannot be interpreted as absolute values and only differences between active ingredients, regions and application periods should be assessed.  相似文献   

5.
何姝  董慧峪  任南琪 《环境科学》2023,44(1):180-188
为阐明我国东南地区典型饮用水源地农药类微污染物的污染特征及生态风险,检测评估了某省7个水库的苯并咪唑类、酰胺类、三唑类和有机磷类等19类共55种常用农药的检出频率、检出浓度以及每种农药对于绿藻、水蚤和鱼类这3种不同营养级生物的风险商.在分析的55种农药中,多菌灵和乙草胺的检出频率为100%,12种农药的检出频率在80%以上.多菌灵的检出浓度最高(77.7 ng·L-1),其次是乙草胺(51.6 ng·L-1).风险评估结果显示,大部分农药在目标区域都处于低风险状态.对于3种生物来说,乙草胺是绿藻的风险主导型农药,而多菌灵是鱼类和水蚤的风险主导型农药.  相似文献   

6.
IntroductionMicro organiccompoundshavebeenidentifiedasoneofthemainriskagentgroupsindrinkingwater.Insurfacewater,agriculturalchemicalsaccountforalargepartoftheorganiccompoundcontents.InEastandSoutheastAsia ,includingChinaandJapan ,cultivatingofrice,themai…  相似文献   

7.
This study provides the presence of carbonic anhydrase(CA) activity in waters of the Yangtze River basin, China, as well as the correlation of CA activity with HCO-3 concentration and CO_2 sink flux. Different degrees of CA activity could be detected in almost all of the water samples from different geological eco-environments in all four seasons. The CA activity of water samples from karst areas was significantly higher than from non-karst areas(PP3-concentration(r = 0.672, P2 sink flux(r = 0.602, P = 0.076) in karst areas. This suggests that CA in waters might have a promoting effect on carbon sinks for atmospheric CO_2 in karst river basins. In conditions of similar geological type, higher CA activity was generally detected in water samples taken from areas that exhibited better eco-environments, implying that the CA activity index of waters could be used as an indicator for monitoring ecological environments and protection of river basins. These findings suggest that the role of CA in waters in the karst carbon sink potential of river basins is worthy of further in-depth studies.  相似文献   

8.
The risk of drinking water is greatly concerned because of the large amount of pesticide applied to paddy field and the contamination of drinking water sources due to the runoff. A mathematical model is developed, based on the mass balance, to predict the fate of paddy field pesticides from application, runoff and mixing in a river, taking account of the physical-chemical properties and processes of volatilization, degradation, adsorption and desorption. The model is applied to a river basin in Japan to estimate the contaminant level of several popularly used pesticides at the water intakes. The health risk in drinking water induced by each pesticide concerned is estimated and evaluated by comparing with the acceptable daily intake values (ADI) and with that induced by trihalomethanes. An index to evaluate the total risk of all pesticides appearing in water is proposed. The methods for risk management are also discussed.  相似文献   

9.
Excessive use of pesticides poses increased risks to non target species including humans. In the developing countries, lack of proper awareness about the toxic potential of pesticides makes the farmer more vulnerable to pesticide linked toxicities, which could lead to diverse pathological conditions. The toxic potential of a pesticide could be determined by their ability to induce genetic mutations and cytotoxicity. Hence, determination of genetic mutation and cytotoxicity of each pesticide is unavoidable to legislate health and safety appraisal about pesticides. The objective of current investigation was to determine the genotoxic and cytotoxic potential of Endosulfan(EN) and Lambda-cyhalothrin(LC); individually and in combination. 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide(MTT) assay was utilized to determine cytotoxicity, while two mutant histidine dependent Salmonella strains(TA98, TA100) were used to determine the mutagenicity of EN and LC.Moreover, mutagenicity assay was conducted with and without S9 to evaluate the effects of metabolic activation on mutagenicity. Even though a dose dependent increase in the number of revertant colonies was detected with EN against both bacterial strains, a highly significant(p 〈 0.05) increase in the mutagenicity was detected in TA98 with S9. In comparison, data obtained from LC revealed less mutagenic potential than EN. Surprisingly,the non-mutagenic individual-concentrations of EN and LC showed dose dependent mutagenicity when combined. Combination of EN and LC synergistically induced mutagenicity both in TA98 and TA100. MTT assay spotlighted comparable dose dependent cytotoxicity effects of both pesticides. Interestingly, the combination of EN and LC produced increased reversion and cytotoxicity at lower doses as compared to each pesticide, concluding that pesticide exposure even at sub-lethal doses can produce cytotoxicity and genetic mutations, which could lead to carcinogenicity.  相似文献   

10.
The Environmental technology (ET) sector delivers environmentally preferably products. Little is known about whether companies in the ET sector set environmental objectives relating to their own production processes. This paper presents results from an online survey on environmental work in enterprises listed by the Swedish Environmental Technology Council (Swentec). The survey found that depending on the specific subsector, only between 21% and 45% of companies provide information about their environmental work on their website. This paper proposes environmental aspects of production and products as bases for corporate greening and for defining ‘green’ and ‘green-green’ business and identifies three main motivations for the companies within ET sector to operate as ‘green-green’ businesses: ‘competitive advantage’, ‘environmental responsibility’ and ‘environmental leadership’.  相似文献   

11.
Global pollinator declines have been attributed to habitat destruction, pesticide use, and climate change or some combination of these factors, and managed honey bees, Apis mellifera, are part of worldwide pollinator declines. Here we exposed honey bee colonies during three brood generations to sub-lethal doses of a widely used pesticide, imidacloprid, and then subsequently challenged newly emerged bees with the gut parasite, Nosema spp. The pesticide dosages used were below levels demonstrated to cause effects on longevity or foraging in adult honey bees. Nosema infections increased significantly in the bees from pesticide-treated hives when compared to bees from control hives demonstrating an indirect effect of pesticides on pathogen growth in honey bees. We clearly demonstrate an increase in pathogen growth within individual bees reared in colonies exposed to one of the most widely used pesticides worldwide, imidacloprid, at below levels considered harmful to bees. The finding that individual bees with undetectable levels of the target pesticide, after being reared in a sub-lethal pesticide environment within the colony, had higher Nosema is significant. Interactions between pesticides and pathogens could be a major contributor to increased mortality of honey bee colonies, including colony collapse disorder, and other pollinator declines worldwide.  相似文献   

12.
In the first tier risk assessment (RA) of pesticides, risk for aquatic communities is estimated by using results from standard laboratory tests with algae, daphnids and fish for single pesticides such as herbicides, fungicides, and insecticides. However, fungi as key organisms for nutrient cycling in ecosystems as well as multiple pesticide applications are not considered in the RA. In this study, the effects of multiple low pesticide pulses using regulatory acceptable concentrations (RACs) on the dynamics of non-target aquatic fungi were investigated in a study using pond mesocosm. For that, fungi colonizing black alder (Alnus glutinosa) leaves were exposed to multiple, low pulses of 11 different pesticides over a period of 60 days using a real farmer''s pesticide application protocol for apple cropping. Four pond mesocosms served as treatments and 4 as controls. The composition of fungal communities colonizing the litter material was analyzed using a molecular fingerprinting approach based on the terminal Restriction Fragment Length Polymorphism (t-RFLP) of the fungal Internal Transcribed Spacer (ITS) region of the ribonucleic acid (RNA) gene(s). Our data indicated a clear fluctuation of fungal communities based on the degree of leaf litter degradation. However significant effects of the applied spraying sequence were not observed. Consequently also degradation rates of the litter material were not affected by the treatments. Our results indicate that the nutrient rich environment of the leaf litter material gave fungal communities the possibility to express genes that induce tolerance against the applied pesticides. Thus our data may not be transferred to other fresh water habitats with lower nutrient availability.  相似文献   

13.
扬州市长江段不同水层中鱼类有机氯农药残留研究   总被引:1,自引:0,他引:1  
鱼肉含有的蛋白质,脂肪,矿物质,维生素对人的健康起到重要的作用,因而被大多数人所青睐。由于有机氯农药具有较高的杀虫活性,曾被广泛使用。中国早已停产,但由于其性质稳定在自然界不易分解属于高残留农药,残留于植物中有机氯农药,可通过"食物链"或其他途径进入动物体内,鱼类也会受影响。本文根据淡水鱼在水中分布状况,选取了扬州市长江段生活在不同水层中三种鱼类为分析对象。选取容易富集有机氯农药的腹部肌肉为实验样品测定部位,采用加速溶剂萃取法前处理分析鱼肉中有机氯农药并对该分析方法进行完善,通过实验总结出能满足环境监测工作中对淡水河流中鱼类有机氯农药测定,并能及时掌握淡水鱼类中有机氯农药对人身健康状况的影响。  相似文献   

14.
农药工业是中国化学工业主要行业之一,有机磷农药在中国的农药结构中占有较高的份额,农药的"三废"问题以废水最为严峻和突出.有机磷农药是由有毒的化学原料合成的一种化学农药,合成过程中要排放出大量废水,每合成1吨农药约消耗3-4t化工原料,排放废水3-2t,且废水污染物浓度高.在分析了不同的有机磷农药其废水的产生来源,实际工作中接触到的淄博农药生产厂家几种主要有机磷农药废水的水量、水质.如何用有机磷农药废水常用的处理方法及回收利用.  相似文献   

15.
We reviewed organophosphorus pesticide use in Japan between 1982 and 2016 using data from the National Institute of Environmental Studies. Organophosphorus pesticide concentrations in river water throughout Japan were taken from the literature, and risk assessments were performed for some organophosphorus pesticides based on risk quotients and hazard quotients. Assessments were performed for 20 common pesticides, including insecticides, fungicides, and herbicides. The amounts used decreased in the order: insecticides?>?herbicides?>?fungicides. Organophosphorus insecticide and fungicide use have decreased over the last four decades, but organophosphorus herbicide use has increased. During this period, annual organophosphorus pesticide use was the highest for chlorpyrifos (105,263?tons/year) and the lowest for glyphosate-sodium (8?tons/year). The ecotoxicological risk assessment indicated that diazinon and fenitrothion posed strong risks to the Japanese aquatic environment, and chlorpyrifos and malathion have moderate risks. None of the pesticides that were assessed posed significant risks to humans. Continued use of organophosphorus pesticides in Japan may cause strong risks to aquatic environments. These risks should be reassessed periodically.  相似文献   

16.
牡丹江作为松花江第二大支流,是国家水污染防治重点流域。通过研究小流域的污染防治对策,可以解决牡丹江的污染及水质安全保障问题,在支流中起到示范作用,从而防止危害松花江的水质安全。本文以“十二五”规划思路为依托,以牡丹江流域为例,探讨小流域的水污染防治对策。  相似文献   

17.
The purpose of this study was to quantify the transfer of viral and bacterial pathogens in water used to dilute pesticides sprayed onto the surfaces of cantaloupe, iceberg lettuce, and bell peppers. The average percent transfer of bacteria was estimated to range from 0.00021 to 9.4%, while average viral transfer ranged from 0.055 to 4.2%, depending on the type of produce. Based on these values the concentrations of hepatitis A virus (HAV) and Salmonella in water necessary to achieve a 1:10,000 annual risk of infection were calculated. Under worst case scenario assumptions, in which a pesticide is applied on the same day that the produce is harvested and when maximum transfer values are used, concentrations of 1.5 × 10−3 CFU Salmonella or 2.7 × 10−7 MPN HAV per 100 ml of the water used for application would result in 1:10,000 annual infection risk to anyone who consumes the fresh produce. If harvesting does not occur until at least 14 days after the application, to produce the same risk of infection, the numbers of Salmonella in 100 ml of water used to dilute the pesticides will be greater by up to five orders of magnitude, while the HAV numbers will have increased by up to two orders of magnitude. Based on the reported concentrations of enteric viruses in surface and ground waters in the United States, a 1:10,000 annual risk of infection could easily be exceeded with some groundwater sources used in the United States. To reduce the risks associated with the consumption of fresh produce, water used to prepare pesticides in spray applications should be evaluated for its microbiological quality.  相似文献   

18.
Chiral pesticides account for 30% of pesticides. Pesticides are inevitably leached into the groundwater by runoff. At the watershed level, the distribution characteristics of enantiomers in sediments collected from the river network of an agricultural area near the middle and lower reaches of the Yangtze River were tested, and their potential correlations with the physicochemical properties and microbial communities of the sediments were analyzed. The sediment pollution was serious at sites 8 and 9, with their pollution source possibly being agricultural or industrial sewage. Moreover, there were higher cumulative contents of pesticide residues at sites 4, 8, and 9. Specifically, Cycloxaprid was the most detected chiral pesticide in the study area, followed by Dinotefuran and Diclofop-methyl. Additionally, Ethiprole and Difenoconazole had strong enantioselectivity in the study area. Interestingly, the enantiomers of some chiral pesticides, such as Tebuconazole, had completely different distributions at different sites. Pearson correlation analysis showed that sediment catalase and microbial biomass carbon were important factors for enantioselectivity of chiral pesticides. The effect of sediment physicochemical properties on enantioselective distribution was achieved by influencing the microorganisms in the sediment. Furthermore, the enantioselective distribution of Tebuconazole was closely related to the genus Arenimonas. Overall, the enantioselective distribution of most of the chiral pesticides was positively correlated with the prokaryotic microbial community. This study provides empirical support for agricultural non-point source pollution caused by chiral pesticides, and also lays a research foundation for exploring the factors that affect the fate of chiral pesticides in the environment.  相似文献   

19.
The present study was performed to characterise in-stream pesticide exposure within the Palatinate vineyard region in south-west Germany, evaluate the influence of buffer strip widths and identify mitigation measures for the relevant entry pathways. In-stream water and sediment samples that were taken at nine sampling sites of different buffer widths following intense rainfall, and edge-of-field runoff that were sampled in erosion rills were analysed regarding 28 active ingredients of pesticides including copper. In-stream samples contained a mix of 8 ± 4 pesticide compounds, resulting in total pesticide concentrations of 1.4-8.9 μg l−1 for water and 16-670 μg kg−1 dw for sediment. Following an exceptional rainfall event with a previous 34-day drought period, pesticide concentrations reached 7.0-83.4 μg l−1. Fungicides were the most important pesticides found and were significantly correlated with the pesticide application frequency and rate. The calculated toxicity values per sample (TUmax) indicated that both organic pesticides and copper concentrations likely cause ecotoxicological effects in the field. The buffer strip width was of little importance for pesticide in-stream concentrations because pesticide entry occurred mainly via the field path network and erosion rills. Pesticide in-stream concentrations were significantly and positively correlated with the concentrations detected in erosion rills (R2 = 0.56). As possible risk mitigation measures, we suggest the implementation of grassed field paths and vegetated ditches or wetlands.  相似文献   

20.
在夏季对海河与渤海湾表层水中溶解态的多氯联苯(PCBs)和有机氯农药(OCPs)的污染状况进行了调查.结果表明,海河和渤海湾表层水中PCBs、六六六和滴滴涕的含量分别为0.06~3.11 μg/L、0.05~1.07 μg/L和0.01~0.15 μg/L.海河干流流域内的工业废水排放等陆源输入可能是渤海湾中PCBs和OCPs的重要来源.研究表明该地区PCBs与水中的DOC(dissolved organic carbon)具有一定的正相关.与国内外类似水体相比,海河中PCBs和OCPs污染情况较为严重,而渤海湾则处于中等水平.  相似文献   

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