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1.
于2018年4—6月采集了江苏省10个市的茶园和农田表层土壤样品,采用气相色谱-三重四级杆质谱仪分析样品中12种拟除虫菊酯类农药的质量比和组成。结果表明,江苏省茶园和农田土壤中广泛检出拟除虫菊酯类农药,总量分别为27.1~50.7,56.9~97.0 ng/g。研究区域的拟除虫菊酯类农药含量存在差异,但组成相近,均是高效氯氟氰菊酯和联苯菊酯的比例较高。与国内其他地区土壤相比,江苏省茶园和农田土壤中拟除虫菊酯含量处于中等水平。  相似文献   

2.
Urban pesticide use has a direct impact on surface water quality. To determine the extent of pesticide contamination, the California Department of Pesticide Regulation initiated a multi-area urban monitoring program in 2008. Water and sediment samples were collected at sites unaffected by agricultural inputs in three areas: Sacramento (SAC), San Francisco Bay (SFB), and Orange County (OC). Samples were analyzed for up to 64 pesticides or degradates. Multiple detections were common; 50 % of the water samples contained five or more pesticides. Statewide, the most frequently detected insecticides in water were bifenthrin, imidacloprid, fipronil, fipronil sulfone, fipronil desulfinyl, carbaryl, and malathion. Bifenthrin was the most common contaminant in sediment samples. Key differences by area: OC had more pesticides detected than SAC or SFB with higher concentrations of fipronil, whereas SAC had higher concentrations of bifenthrin. The most frequently detected herbicides were 2,4-D, triclopyr, dicamba, diuron, and pendimethalin. Key differences by area: OC and SFB had higher concentrations of triclopyr, whereas SAC had higher concentrations of 2,4-D and dicamba. Detection frequency, number of pesticides per sample, and pesticide concentration increased during rainstorm events. In water samples, all of the bifenthrin, malathion, fipronil, permethrin, and λ-cyhalothrin detections, and most of the fipronil sulfone and cyfluthrin detections were above their lowest US EPA aquatic benchmark. Diuron was the only herbicide that was detected above its lowest benchmark. Based on the number of pesticides and exceedances of aquatic benchmarks or the high number of sediment toxicity units, pesticides are abundant in California surface waters.  相似文献   

3.
The California??s San Joaquin River and its tributaries including Orestimba (ORC) and Del Puerto (DPC) Creeks are listed on the 2006 US EPA Clean Water Act §303(d) list for pesticide impairment. From December 2007 through June 2008, water and sediment samples were collected from both creeks in Stanislaus County to determine concentrations of organophosphorus (OP) and pyrethroid insecticides and to identify toxicity to Ceriodaphnia dubia and Hyalella azteca. OPs were detected in almost half (10 of 21) of the water samples, at concentrations from 0.005 to 0.912 ??g L???1. Diazinon was the most frequently detected OP, followed by chlorpyrifos and dimethoate. Two water samples were toxic to C. dubia; based on median lethal concentrations (LC50), chlorpyrifos was likely the cause of this toxicity. Pyrethroids were detected more frequently in sediment samples (18 detections) than in water samples (three detections). Pyrethroid concentrations in water samples ranged from 0.005 to 0.021 ??g L???1. These concentrations were well below reported C. dubia LC50s, and toxicity was not observed in laboratory bioassays. Cyfluthrin, bifenthrin, esfenvalerate, and ??-cyhalothrin were detected in sediment samples at concentrations ranging from 1.0 to 74.4 ng g???1, dry weight. At DPC, all but one sediment sample caused 100% toxicity to H. azteca. Based on estimated toxicity units (TUs), bifenthrin was likely responsible for this toxicity and ??-cyhalothrin also contributed. At ORC, survival of H. azteca was significantly reduced in four of the 11 sediment samples. However, pyrethroids were detected in only two of these samples. Based on TUs, bifenthrin and ??-cyhalothrin likely contributed to the toxicity.  相似文献   

4.
Butter (45) and ghee (55) samples were collected from rural and urban areas of cotton growing belt of Haryana and analysed for detecting the residues of organochlorine, synthetic pyrethroid and organophosphate insecticides. The estimation was carried out by using multi residue analytical technique employing GC-ECD and GC-NPD systems equipped with capillary columns. Butter samples were comparatively more contaminated (97%) than ghee (94%), showing more contamination with organochlorine insecticides from urban samples. About 11% samples of butter showed endosulfan residues above MRL value and 2% samples had residues of synthetic pyrethroids and organophosphates each above their respective MRL values. In ghee, residues of HCH & DDT both and of endosulfan exceeded the MRL values in 5 and 20% samples, respectively. Among organophosphates, only chlorpyriphos was detected with 9% samples showing its residue above MRL value. Irrespective of contamination levels, residues above the MRL values were more in ghee. More extensive study covering other agricultural regions/zones of Haryana has been suggested to know the overall scenario of contamination of milk products.  相似文献   

5.
Synthetic pyrethroids have been detected in recent California surface water monitoring. Filtration is avoided during sample workup because pyrethroids are extremely hydrophobic, tending to sorb to most surfaces. The resultant analytical pyrethroid concentrations reflect both dissolved pyrethroid and pyrethroid associated with suspended sediment in the water column. Such “whole-water” analytical data are not directly comparable to aquatic acute toxicity effect concentrations measured in laboratory sediment-free water. Consequently, any potential aquatic toxicity risk is indeterminate. In this study a simple probabilistic model was developed to allow a screening-level assessment of pyrethroid whole-water monitoring data. The results suggest that water column toxicity of pyrethroids is possible in California's agriculturally-dominated tributaries, and indicate that additional monitoring to better characterize pyrethroid water-column concentrations are warranted. Model refinement will depend on future work that more firmly establishes the relationship between pyrethroid partitioning and bioavailability, and that addresses the potential influence of dissolved organic carbon on pyrethroid sorption and bioavailability.  相似文献   

6.
This project was designed to establish baseline aquatic biological community structure and physical habitat conditions in select wadeable streams within the California Central Valley. A secondary objective was to evaluate possible water quality differences between site types and seasons. Two agricultural and two urban streams were monitored in spring and fall for two consecutive years beginning in the fall of 2002. Bioassessment sampling was conducted according to modified US EPA methods. The study included physical habitat assessment, water and sediment chemical analysis and characterization of the benthic macroinvertebrate community at each site. Water samples were analyzed for selected organophosphate insecticides, pyrethroid insecticides and herbicides, while sediment samples were analyzed for pyrethroids only. All sites had substantial physical habitat and water quality impairments, and the absence of pollution intolerant macroinvertebrates and dominance of pollution tolerant macroinvertebrates were indications of biological impairment. Due to the limited amount of water quality and pesticide data collected, it was not possible to definitively demonstrate any cause and effect relationships between BMI community structure and water quality or pesticide concentrations. Though most physical habitat parameters were similar and EPA physical habitat scores revealed on no significant differences between urban and agricultural sites (P? = ?0.290), a significant difference was seen in substrate embeddedness (P? = ?0.020). Dominant taxon found at all sites were chironomids, amphipods, and oligochaetes. Benthic macroinvertebrate metrics were significantly different between both types of sites (P? = ?0.001) and seasons (P? = ?0.014). Chironomidae taxon and those of the functional feeding group scrapers were greater at urban sites, while those of the functional feeding group filterers were greater at agricultural sites. In addition, the metric groups Chironomidae, filterers, and predators were found in greater numbers in the spring than the fall.  相似文献   

7.
The Salinas River watershed along the central coast of California, U.S.A., supports rapidly growing urban areas and intensive agricultural operations. The river drains to an estuarine National Wildlife Refuge and a National Marine Sanctuary. The occurrence, spatial patterns, sources and causesof aquatic toxicity in the watershed were investigated by sampling four sites in the main river and four sites in representative tributaries during 15 surveys between September1998 and January 2000. In 96 hr toxicity tests, significant Ceriodaphnia dubia mortality was observed in 11% of the mainriver samples, 87% of the samples from a channel draining anurban/agricultural watershed, 13% of the samples fromchannels conveying agricultural tile drain runoff, and in 100% of the samples from a channel conveying agricultural surface furrow runoff. In six of nine toxicity identificationevaluations (TIEs), the organophosphate pesticides diazinon and/or chlorpyrifos were implicated as causes of observed toxicity, and these compounds were the most probable causes oftoxicity in two of the other three TIEs. Every sample collectedin the watershed that exhibited greater than 50% C. dubia mortality (n = 31) had sufficient diazinon and/or chlorpyrifos concentrations to account for the observed effects.Results are interpreted with respect to potential effects on other ecologically important species.  相似文献   

8.
A novel reagent was introduced for the facile and sensitive spectrophotometric determination of syntheitic pyrethroids in their formulations (fenvalerate, cypermethrin and decamethrin), water and grain samples. These methods were based on the hydrolysis of synthetic pyrethroids under the alkaline conditions to form respective aldehyde groups. These groups were condensation with 3-methyl-2-benzothiazolinone hydrochloride (MBTH) to yield color derivatives having λmax at 520 nm for fenvalerate, 516 nm for cypermethrin and 512 nm for decamethrin. The proposed method could be successfully applied for the determination of synthetic pyrethroids in their formulations, water and grain samples.  相似文献   

9.
Status of insecticide contamination of soil and water in Haryana, India   总被引:2,自引:0,他引:2  
Twelve samples each of soil and ground water were collected from paddy-wheat, paddy-cotton, sugarcane fields and tube wells from same or near by fields around Hisar, Haryana, India during 2002–2003 to monitor pesticide residues. Residues were estimated by GC-ECD and GC-NPD systems equipped with capillary columns for organochlorine, synthetic pyrethroid and organophosphate insecticides. In soil, HCH (0.002–0.051 μg g−1), DDT (0.001–0.066 μg g−1), endosulfan (0.002–0.039 μg g−1) and chlordane (0.0002–0.019 μg g−1) among organochlorines, cypermethrin (0.001–0.035 μg g−1) and fenvalerate (0.001–0.022 μg g−1) among synthetic pyrethroids and chlorpyriphos (0.002–0.172 μg g−1), malathion (0.002–0.008 μg g−1), quinalphos (0.001–0.010 μg g−1) among organophosphates were detected. Dominant contaminants were DDT, cypermethrin and chlorpyriphos from the respective groups. In water samples, HCH, DDT, endosulfan and cypermethrin residues were observed frequently. Only chlorpyriphos among organophosphates was detected in 10 samples. On consideration of tube well water for drinking purpose, about 80% samples were found to contain residues above the regulatory limits.  相似文献   

10.
The physicochemical analysis of bottom sediments of the Lujan River was done on samples from 14 sites situated along its course and covered grain size and organic matter, total N and P, sulfides, heavy metals, organochlorine, and pyrethroid pesticides. In addition, acute 10-day whole-sediment laboratory toxicity tests were carried with each sample, using the native amphipod Hyalella curvispina as test organism. In order to correlate both types of results, data were assessed by multivariate analysis, including principal component analysis (PCA). The physicochemical profile of samples resulted similar along the river course, though several anomalous data were registered in the middle course of the river, mainly in samples taken downstream a large industrial complex; with a few exceptions in upper basin sites characterized by the dominance of agricultural activities, the pesticides concentration were consistently below the analytical detection limits. Almost 50 % of the samples induced adverse effects on the amphipod when testing sublethal and lethal end points. The toxicity of the samples in terms of survival rate was extremely high in two sites, in particular in samples taken downstream the Pilar industrial complex. The integration of a selection of physicochemical and toxicological parameters of the sediments by PCA allowed discriminating areas of the river basin according the type and intensity of their particular pollution condition.  相似文献   

11.
Recent and past studies have documented the prevalence of pyrethroid and organophosphate pesticides in urban and agricultural watersheds in California. While toxic concentrations of these pesticides have been found in freshwater systems, there has been little research into their impacts in marine receiving waters. Our study investigated pesticide impacts in the Santa Maria River estuary, which provides critical habitat to numerous aquatic, terrestrial, and avian species on the central California coast. Runoff from irrigated agriculture constitutes a significant portion of Santa Maria River flow during most of the year, and a number of studies have documented pesticide occurrence and biological impacts in this watershed. Our study extended into the Santa Maria watershed coastal zone and measured pesticide concentrations throughout the estuary, including the water column and sediments. Biological effects were measured at the organism and community levels. Results of this study suggest the Santa Maria River estuary is impacted by current-use pesticides. The majority of water samples were highly toxic to invertebrates (Ceriodaphnia dubia and Hyalella azteca), and chemistry evidence suggests toxicity was associated with the organophosphate pesticide chlorpyrifos, pyrethroid pesticides, or mixtures of both classes of pesticides. A high percentage of sediment samples were also toxic in this estuary, and sediment toxicity occurred when mixtures of chlorpyrifos and pyrethroid pesticides exceeded established toxicity thresholds. Based on a Relative Benthic Index, Santa Maria estuary stations where benthic macroinvertebrate communities were assessed were degraded. Impacts in the Santa Maria River estuary were likely due to the proximity of this system to Orcutt Creek, the tributary which accounts for most of the flow to the lower Santa Maria River. Water and sediment samples from Orcutt Creek were highly toxic to invertebrates due to mixtures of the same pesticides measured in the estuary. This study suggests that the same pyrethroid and organophosphate pesticides that have been shown to cause water and sediment toxicity in urban and agriculture water bodies throughout California, have the potential to affect estuarine habitats. The results establish baseline data in the Santa Maria River estuary to allow evaluation of ecosystem improvement as management initiatives to reduce pesticide runoff are implemented in this watershed.  相似文献   

12.
Analysis of 84 farm gate samples of seasonal vegetables carried out on GC-ECD and GC-NPD systems equipped with capillary columns by using a multi residue analytical technique revealed that 26% samples contained residues above MRL values. The contamination was mainly with organophosphates followed by synthetic pyrethroids and organochlorines. Among organophosphates, residues of monocrotophos, quinalphos and chlorpyriphos exceeded the MRL value in 23% samples. Residues of monocrotophos were higher than MRL value in 3 samples of brinjal and one sample each of okra, cauliflower and smooth gourd, of chlorpyriphos in 3 samples of cauliflower and 8 of cabbage and of quinalphos in one sample each of okra and cauliflower. Among synthetic pyrethroids, cypermethrin was the major contaminant and its residue exceeded the MRL value in one sample each of brinjal, okra and cucumber. Only aldicarb among the carbamates was detected in potato. The residues of some organochlorines, i.e. HCH, DDT and endosulfan were found in all the samples but did not exceed the tolerence limit.  相似文献   

13.
In this study, 226 samples of seven types of domestic vegetables collected from several vegetable-growing regions in Hebei Province of China were tested for the presence of 38 different agricultural pesticides using a gas chromatograph equipped with electron capture and nitrogen phosphorus detectors. The aim of this study was to investigate the distribution of pesticides in main vegetables from Hebei Province. Results showed that, in 65.93 % of the samples, no residues were found, 31.42 % of the samples contained pesticide residues at or below the maximum residue levels (MRLs), and 2.65 % of the samples contained pesticide residues above MRL. The most frequently detected pesticides were acephate (31), followed by cyhalothrin (15), bifenthrin (8), omethoate (6), isazophos (6), dimethoate (5), chlorpyrifos (2), and malathion (1). Some (1.33 %) of the samples contained multiple residues. The results provide useful information on the current contamination status of a key agricultural area in North China, and points to the continuous monitoring and strict regulation of pesticide use on vegetables are necessary.  相似文献   

14.
In the present study we quantified the residues of organophosphorus (e.g. ethion and chlorpyrifos), organochlorine (e.g. heptachlor, dicofol, alpha-endosulfan, beta-endosulfan, endosulfan sulfate) and synthetic pyrethroid (e.g. cypermethrin and deltamethrin) pesticides in made tea, fresh tea leaves, soils and water bodies from selected tea gardens in the Dooars and Hill regions of West Bengal, India during April and November, 2006. The organophosphorus (OP) pesticide residues were detected in 100% substrate samples of made tea, fresh tea leaves and soil in the Dooars region. In the Hill region, 20% to 40% of the substrate samples contained residues of organophosphorus (OP) pesticides. The organochlorine (OC) pesticide residues were detected in 33% to 100% of the substrate samples, excluding the water bodies in the Dooars region and 0% to 40% in the Hill region. The estimated mean totals of studied pesticides were higher in fresh tea leaves than in made tea and soils. The synthetic pyrethroid (SP) pesticide residues could not be detected in the soils of both the regions and in the water bodies of the Dooars. Sixteen percent and 20% of the made tea samples exceeded the MRL level of chlorpyrifos in Dooars and Hill regions respectively. The residues of heptachlor exceeded the MRL in 33% (April) and 100% (November) in the Dooars and 40% (April) and 20% (November) in the Hill region. Based on the study it was revealed that the residues of banned items like heptachlor and chlorpyrifos in made tea may pose health hazards to the consumers.  相似文献   

15.
There is concern that insecticides are able to mimic the action of 17beta-estradiol by interaction with the human estrogen receptor. Pyrethroids are commonly used insecticides and several have been assessed for potential endocrine disrupting activity by various methods. It has been noted that some metabolites of pyrethroids, in particular, permethrin and cypermethrin, have chemical structures that are more likely to interact with the cellular estrogen receptor than the parent pyrethroid. For this study permethrin and cypermethrin metabolites 3-(4-hydroxy-3-phenoxy)benzyl alcohol, 3-(4-hydroxy-3-phenoxy)benzoic acid, and N-3-(phenoxybenzoyl)glycine were synthesised, and together with the commercially available 3-phenoxybenzyl alcohol, 3-phenoxybenzaldehyde, and 3-phenoxybenzoic acid, were studied in a recombinant yeast assay expressing human estrogen receptors (YES). Three metabolites, 3-phenoxybenzyl alcohol, 3-(4-hydroxy-3-phenoxy)benzyl alcohol, and 3-phenoxybenzaldehyde, showed estrogenic activity of approximately 10(5) less than that of 17beta-estradiol. No activity was observed in the yeast assay for 3-phenoxybenzoic acid, 3-(4-hydroxy-3-phenoxy)benzoic acid, and N-3-(phenoxybenzoyl)glycine. The results from this study show that pyrethroid metabolites are capable of interacting with the human estrogen receptor, and so might present a risk to human health and environmental well being. The impact would be expected to be small, but still add to the overall environmental xenoestrogen load.  相似文献   

16.
以正己烷/丙酮混合溶剂(体积比为1∶1)为提取剂,采用Florisil柱净化、气相色谱电子捕获检测器测定土壤中菊酯类农药残留,优化了提取条件。4种菊酯类农药在0.010 mg/L~1.00 mg/L范围内线性良好,方法检出限为0.005 mg/L~0.010 mg/L,甲氰菊酯回收率为85.2%~103%,RSD为2.3%~5.4%;氯氰菊酯回收率为80.5%~103%,RSD为2.8%~6.7%;氰戊菊酯回收率为80.2%~103%,RSD为2.3%~6.0%;溴氰菊酯回收率为80.8%~103%,RSD为2.4%~6.2%。  相似文献   

17.
Market samples (60) of six seasonal vegetables were monitoredduring 1996–1997 to determine the magnitude of pesticidalcontamination. The estimation of insecticide residuesrepresenting four major chemical groups i.e. organochlorine,organophosphorous, synthetic pyrethroid and carbamate, was doneby adopting a multiresidue analytical technique employingGC-ECD and GC-NPD systems with capillary columns. The testedsamples showed 100% contamination with low but measurableamounts of residues. Among the four chemical groups, theorganophosphates were dominant followed by organochlorines,synthetic pyrethroids and carbamates. About 23% of the samplesshowed contamination with organophosphorous compounds abovetheir respective MRL values. More extensive studies coveringdifferent regions of Haryana state are suggested to get a clearidea of the magnitude of vegetable contamination with pesticideresidues.  相似文献   

18.
The increasing application of pesticides in the uplands of northern Thailand has increased the transfer of pesticides to surface water. To assess the risk of pesticide use for stream water quality, we monitored the concentrations of seven pesticides (atrazine, dichlorvos, chlorpyrifos, dimethoate, chlorothalonil, (α-, β-) endosulfan, cypermethrin) frequently used in the Mae Sa watershed (77 km2) in water and sediment samples over a period of one and a half years (2007–2008). All investigated pesticides were recorded in the river. Chlorpyrifos was detected most often in water samples (75 % at the headwater station), while cypermethrin was most often found in riverbed (86 %) and in all suspended sediment samples. The highest concentrations of the pesticides were detected during the rainy season. About 0.002 to 4.1 % by mass of the applied pesticides was lost to surface water. The risk assessment was based on the risk characterization ratio (RCR). The RCRs of dichlorvos in water, (α-, β-) endosulfan, and cypermethrin in water and sediments were higher than unity indicating that they are likely to pose a threat to aquatic ecosystem. Finally, we discuss the role of sampling design on ecotoxicological risk assessment. Our study shows that pesticide contamination of surface waters is an environmental issue in the Mae Sa watershed and that measures need to be undertaken to reduce the loss of pesticides from soil to surface waters.  相似文献   

19.
毛细管柱气相色谱法测定水中痕量拟除虫菊酯杀虫剂   总被引:11,自引:1,他引:10  
采用石油醚萃取水样 ,萃取液经氮气吹扫浓缩后 ,用气相色谱仪对水样中拟除虫菊酯杀虫剂——甲氰菊酯、三氟氯氰菊酯 (功夫 )、高效氯氰菊酯、氰戊菊酯、溴氰菊酯进行了定量测定。由于毛细管柱的高柱效和微池 ECD的高灵敏度 ,使得上述目标组分与水样中的其它杂质能达到较好的分离 ,即使含量极低也能被检出。本方法省去了样品萃取液的净化处理这一步骤 ,可较快地测定拟除虫菊酯杀虫剂 ,在污染事故应急监测方面具有实用性。  相似文献   

20.
Benthic algal assemblages, water chemistry, and habitat were characterized at 25 stream sites in the Willamette Basin, Oregon, during low flow in 1994. Seventy-three algal samples yielded 420 taxa — mostly diatoms, blue-green algae, and green algae. Algal assemblages from depositional samples were strongly dominated by diatoms (76% mean relative abundance), whereas erosional samples were dominated by blue-green algae (68% mean relative abundance).Canonical correspondence analysis (CCA) of semiquantitative and qualitative (presence/absence) data sets identified four environmental variables (maximum specific conductance, % open canopy, pH, and drainage area) that were significant in describing patterns of algal taxa among sites. Based on CCA, four groups of sites were identified: streams in forested basins that supported oligotrophic taxa, such as Diatoma mesodon;small streams in agricultural and urban basins that contained a variety of eutrophic and nitrogen-heterotrophic algal taxa; larger rivers draining areas of mixed land use that supported planktonic, eutrophic, and nitrogen-heterotrophic algal taxa; and streams with severely degraded or absent riparian vegetation (> 75% open canopy) that were dominated by other planktonic, eutrophic, and nitrogen-heterotrophic algal taxa. Patterns in water chemistry were consistent with the algal autecological interpretations and clearly demonstrated relationships between land use, water quality, and algal distribution patterns.  相似文献   

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