宁波市鄞州区农作物农药残留现状与控制对策

对鄞州区种植的稻谷、叶菜类、水果类、豆类、茄果类和块茎类农产品按月进行了411个批次抽样,按照国家相关规定对22个农药项目进行了检测。检测结果发现样本农药项目检出率为0.3%,农产品农药残留合格率97.82%,农药残留检出项目中88.89%是杀虫剂。超出农药残留标准的样本主要是5-10月的青菜,叶菜类超标样本率达到3.72%。农药残留超标样本在平原、滨海地区种植散户中有发现,而在山区各规模农户中均有发现。小学文化程度农户样本农药残留超标率高达4.50%,是大学文化程度农户样本农药残留超标率的6.16倍。为了降低鄞州区农作物农药残留率,提出5方面的控制对策。     

Pesticide and Transformation Product Detections and Age‐Dating Relations from Till and Sand Deposits1

Abstract:  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.     

Transport and fate of nitrate and pesticides: hydrogeology and riparian zone processes

There is continuing concern over potential impacts of widespread application of nutrients and pesticides on ground- and surface-water quality. Transport and fate of nitrate and pesticides were investigated in a shallow aquifer and adjacent stream, Cow Castle Creek, in Orangeburg County, South Carolina. Pesticide and pesticide degradate concentrations were detected in ground water with greatest frequency and largest concentrations directly beneath and downgradient from the corn (Zea mays L.) field where they were applied. In almost all samples in which they were detected, concentrations of pesticide degradates greatly exceeded those of parent compounds, and were still present in ground waters that were recharged during the previous 18 yr. The absence of both parent and degradate compounds in samples collected from deeper in the aquifer suggests that this persistence is limited or that the ground water had recharged before use of the pesticide. Concentrations of NO(-)(3) in ground water decreased with increasing depth and age, but denitrification was not a dominant controlling factor. Hydrologic and chemical data indicated that ground water discharges to the creek and chemical exchange takes place within the upper 0.7 m of the streambed. Ground water had its greatest influence on surface-water chemistry during low-flow periods, causing a decrease in concentrations of Cl(-), NO(-)(3), pesticides, and pesticide degradates. Conversely, shallow subsurface drainage dominates stream chemistry during high-flow periods, increasing stream concentrations of Cl(-), NO(-)(3), pesticides, and pesticide degradates. These results point out the importance of understanding the hydrogeologic setting when investigating transport and fate of contaminants in ground water and surface water.     

Pesticide risk reduction on crops in the Province of Ontario

We analyzed the changes in pesticide use and risk in the Province of Ontario, Canada, from 1973 to 1998 to monitor the success of Food Systems 2002, a program to reduce pesticide use by 50%. Pesticide risk was calculated by multiplying the amount of pesticide used (kilograms of active ingredient) by the Environmental Impact Quotient (EIQ), a score for the potential risk of pesticides to farmworkers, consumers, and the environment. Pesticide use increased by 46% from 1973 to 1983. From 1983, the baseline year for Food Systems 2002, to 1998, pesticide use decreased by 38.5% and risk declined 39.5%. The reductions in pesticide use and risk were primarily on corn (Zea mays L.) and tobacco (Nicotiana tabacum L.), the crops with the highest pesticide use in 1983. Total pesticide use on soybean [Glycine max (L.) Merr.] did not change, but the mean application rate (kg ha(-1)) decreased by 57%. Corn and soybean account for 65% of pesticide use, but have a relatively low pesticide use and risk per hectare and per tonne of production. Total pesticide use on tobacco, fruits, and vegetables was lower than on corn or soybean, but the pesticide use and risk per hectare were much higher. Small reductions in pesticide use on corn and soybean may allow a 50% reduction in pesticide use, but greater reductions in risk can be achieved by reducing the use of "high risk" pesticides on fruit and vegetables.     

Summary of well water sampling in California to detect pesticide residues resulting from nonpoint-source applications

This report summarizes well sampling protocols, data collection procedures, and analytical results for the presence of pesticides in ground water developed by the California Department of Pesticide Regulation (DPR). Specific well sampling protocols were developed to meet regulatory mandates of the Pesticide Contamination Prevention Act (PCPA) of 1986 and to provide further understanding of the agronomic, chemical, and geographic factors that contribute to movement of residues to ground water. The well sampling data have formed the basis for the DPR's regulatory decisions. For example, a sampling protocol, the Four-Section Survey, was developed to determine if reported detections were caused by nonpoint-source agricultural applications, a determination that can initiate formal review and subsequent regulation of a pesticide. Selection of sampling sites, which are primarily rural domestic wells, was initially based on pesticide use and cropping patterns. Recently, soil and depth-to-ground water data have been added to identify areas where a higher frequency of detection is expected. In accordance with the PCPA, the DPR maintains a database for all pesticide well sampling in California with submission required by all state agencies and with invitations for submission extended to all local and federal agencies or other entities. To date, residues for 16 active ingredients and breakdown products have been detected in California ground water as a result of legal agricultural use. Regulations have been adopted for all detected parent active ingredients, and they have been developed regardless of the level of detection.     

Sustainable pesticide governance in Bangladesh: socio-economic and legal status interlinking environment,occupational health and food safety

Pesticides, regardless of their known toxic impacts to human health and environment, are widely used in the rapid growing agricultural sectors of developing countries. As an agricultural country with small lands and enormous population to feed, a developing country like Bangladesh rely heavily on the uses of pesticides to increase crop yields. Nevertheless, during the past decades, Peoples’ Republic of Bangladesh has experienced 26.46% decrease in total pesticide consumption. However, the presence of unregistered pesticides in the environmental samples and agricultural products has pointed out the weakness in the existing legal regime of the pesticide governance. This, in turn, is threatening the livelihood and health of the farmers, food safety and consumer health. This paper reviews the antiquity of the status of pesticide consumption, evolution and drawbacks of pesticide in the context of existing socio-economic position of Bangladesh. A consolidated uniform system is lacking to project pesticide management in the country. Existing legal policy, rules and regulations in the context of international agreements regarding pesticide management have been reviewed and suggested for further amendment. Moreover, role of green microfinance in sustainable management of pesticides and food safety were recommended. A framework is proposed for pesticide governance with a stronger pesticide surveillance program and coordination of ministries interlinking environmental, occupational health and food safety.     

Comparison of Two Parametric Methods to Estimate Pesticide Mass Loads in California’s Central Valley1

Saleh, Dina K., David L. Lorenz, and Joseph L. Domagalski, 2010. Comparison of Two Parametric Methods to Estimate Pesticide Mass Loads in California’s Central Valley. Journal of the American Water Resources Association (JAWRA) 00(0):1‐11. DOI: 10.1111/j.1752‐1688.2010.00506.x Abstract: Mass loadings were calculated for four pesticides in two watersheds with different land uses in the Central Valley, California, by using two parametric models: (1) the Seasonal Wave model (SeaWave), in which a pulse signal is used to describe the annual cycle of pesticide occurrence in a stream, and (2) the Sine Wave model, in which first‐order Fourier series sine and cosine terms are used to simulate seasonal mass loading patterns. The models were applied to data collected during water years 1997 through 2005. The pesticides modeled were carbaryl, diazinon, metolachlor, and molinate. Results from the two models show that the ability to capture seasonal variations in pesticide concentrations was affected by pesticide use patterns and the methods by which pesticides are transported to streams. Estimated seasonal loads compared well with results from previous studies for both models. Loads estimated by the two models did not differ significantly from each other, with the exceptions of carbaryl and molinate during the precipitation season, where loads were affected by application patterns and rainfall. However, in watersheds with variable and intermittent pesticide applications, the SeaWave model is more suitable for use on the basis of its robust capability of describing seasonal variation of pesticide concentrations.     

Beyond a bottle of liquid: pesticide dependence in transitional rural China

Pesticide dependence is a major threat to food safety and local environment. Although numerous studies have explored different causes of pesticide dependence, few have examined how pesticides are locked into agricultural modernisation and rural transformation. Based on a case study of a Chinese village, this paper demonstrates how agricultural modernisation trajectory and rural changes have perpetuated the use of pesticides as necessities in agriculture as well as for farmers' livelihoods. Modern technologies, such as hybrid rice, conservation tillage, changes in crop structure, and reduction of intercropping all contribute highly towards pesticide dependence. The household responsibility system in China has provided the institutional foundation for increased pesticide use. Rural transformations driven by livelihoods diversification have created conducive social spaces for pesticide application. To step out of pesticide dependence, promotion of genetic diversity in agriculture, a reassessment of locational suitability of conservation tillage, institutional strengthening and the promotion of integrated pest management methods are suggested.     

Evaluation of Three Watershed‐Scale Pesticide Environmental Transport and Fate Models1

Abstract: The U.S. Environmental Protection Agency (USEPA) Office of Pesticide Programs (OPP) has completed an evaluation of three watershed‐scale simulation models for potential use in Food Quality Protection Act pesticide drinking water exposure assessments. The evaluation may also guide OPP in identifying computer simulation tools that can be used in performing aquatic ecological exposure assessments. Models selected for evaluation were the Soil Water Assessment Tool (SWAT), the Nonpoint Source Model (NPSM), a modified version of the Hydrologic Simulation Program‐Fortran (HSPF), and the Pesticide Root Zone Model‐Riverine Water Quality (PRZM‐RIVWQ) model. Simulated concentrations of the pesticides atrazine, metolachlor, and trifluralin in surface water were compared with field data monitored in the Sugar Creek watershed of Indiana’s White River basin by the National Water Quality Assessment (NAWQA) program. The evaluation not only provided USEPA with experience in using watershed models for estimating pesticide concentration in flowing water but also led to the development of improved statistical techniques for assessing model accuracy. Further, it demonstrated the difficulty of representing spatially and temporally variable soil, weather, and pesticide applications with relatively infrequent, spatially fixed, point estimates. It also demonstrated the value of using monitoring and modeling as mutually supporting tools and pointed to the need to design monitoring programs that support modeling.     

Mitigation assessment of vegetated drainage ditches for collecting irrigation runoff in California

Widespread contamination of California water bodies by the organophosphate insecticides diazinon and chlorpyrifos is well documented. While their usage has decreased over the last few years, a concomitant increase in pyrethroid usage (e.g., permethrin) (replacement insecticides) has occurred. Vegetated agricultural drainage ditches (VADD) have been proposed as a potential economical and environmentally efficient management practice to mitigate the effects of pesticides in irrigation and storm runoff. Three ditches were constructed in Yolo County, California for a field trial. A U-shaped vegetated ditch, a V-shaped vegetated ditch, and a V-shaped unvegetated ditch were each amended for 8 h with a mixture of diazinon, permethrin, and suspended sediment simulating an irrigation runoff event. Water, sediment, and plant samples were collected spatially and temporally and analyzed for diazinon and permethrin concentrations. Pesticide half-lives were similar between ditches and pesticides, ranging from 2.4 to 6.4 h. Differences in half-distances (distance required to reduce initial pesticide concentration by 50%) among pesticides and ditches were present, indicating importance of vegetation in mitigation. Cis-permethrin half-distances in V ditches ranged from 22 m (V-vegetated) to 50 m (V-unvegetated). Half-distances for trans-permethrin were similar, ranging from 21 m (V-vegetated) to 55 m (V-unvegetated). Diazinon half-distances demonstrated the greatest differences (55 m for V-vegetated and 158 m for V-unvegetated). Such economical and environmentally successful management practices will offer farmers, ranchers, and landowners a viable alternative to more conventional (and sometimes expensive) practices.     

Turfgrass thatch effects on pesticide leaching: a laboratory and modeling study

Process-based models are frequently used to assess the water quality impacts of turfgrass management emanating from proposed or existing golf courses. Thatch complicates the prediction of pesticide transport because surface-applied pesticides must pass through an organic-rich layer before entering the soil. This study was conducted to (i) compare the use of a linear equilibrium model (LEM) and two-site nonequilibrium (2SNE) model to predict pesticide transport through soil and thatch + soil columns, and (ii) evaluate thatch effects on pesticide transport through soil columns with a volume-averaging approach. Pesticide breakthrough curves were obtained for soil and thatch + soil columns from a 1 cm h(-1) flux applied one day after applying triclopyr (3,5,6-trichloro-2-pyridinyloxyacetic acid) and carbaryl (1-napthyl-methyl carbamate). Pesticide and bromide transport parameters indicated that nonequilibrium processes were affecting pesticide transport. Columns containing zoysiagrass (Zoysia japonica Steud.) thatch had lower triclopyr and carbaryl leaching losses than did soil-only columns, although total reductions attributable to thatch did not exceed 15% of the applied pesticide. When laboratory-based retardation factors were used, the 2SNE model explained 88 to 93% of the variability for triclopyr and 70 to 94% of the variability for carbaryl. Laboratory-based retardation factors performed well in a 2SNE model to predict the peak concentration and tailing behavior of triclopyr and carbaryl with a volume-averaging approach. These results suggest that separate representation of the thatch layer in process-based models is not a prerequisite to obtain reasonable estimates of pesticide transport under steady state flow conditions.     

PESTICIDES AND PESTICIDE DEGRADATION PRODUCTS IN STORMWATER RUNOFF: SACRAMENTO RWER BASIN,CALIFORNIA1

ABSTRACT: Pesticides in stormwater runoff, within the Sacramento River Basin, California, were assessed during a storm that occurred in January 1994. Two organophosphate insecticides (diazinon and methidathion), two carbamate pesticides (molinate and carbofuran), and one triazine herbicide (simazine) were detected. Organophosphate pesticide concentrations increased with the rising stage of the hydrographs; peak concentrations were measured near peak discharge. Diazinon oxon, a toxic degradation product of diazinon, made up approximately 1 to 3 percent of the diazinon load. The Feather River was the principal source of organophosphate pesticides to the Sacramento River during this storm. The concentrations of molinate and carbofuran, pesticides applied to rice fields during May and June, were relatively constant during and after the storm. Their presence in surface water was attributed to the flooding and subsequent drainage, as a management practice to degrade rice stubble prior to the next planting. A photo-degradation product of molinate, 4-keto molinate, was in all samples where molinate was detected and made up approximately 50 percent of the total molinate load. Simazine, a herbicide used in orchards and to control weeds along the roadways, was detected in the storm runoff, but it was not possible to differentiate the two sources of that pesticide to the Sacramento River.     

Pesticide tolerance of Paenibacillus sp. D1 and its chitinase

Excessive use of pesticides in agriculture has led to several problems pertaining to loss of soil fertility and environmental degradation. Biological control agents offer the best alternative to reduce use of toxic pesticides. Paenibacillus sp. D1 isolated from the effluent treatment plant of a seafood processing industry exhibited broad spectrum tolerance towards a number of pesticides at concentrations higher than recommended for field applications. The isolate showed enhanced growth and chitinase production in the presence of some protectant fungicides. None of the tested demethylase inhibitor (DMI) fungicides inhibited growth and chitinase production except triadimefon. The isolate was also tolerant to most commonly used insecticides belonging to the organophosphate, carbamate and cyclodiene organochloride classes. Chitinase of Paenibacillus sp. D1 was found to be more tolerant than the organism itself and was highly stable in the presence of pesticides at the temperature under field conditions in Gujarat, India, i.e. 40 °C. This was suggestive of its potential in integrated pest management (IPM) to significantly reduce the use of harmful chemicals. To our knowledge this is the first extensive study on pesticide tolerance of the Paenibacillus species and its chitinase.     

Fate of pesticides in combined paddy rice-fish pond farming systems in northern Vietnam

During the last decades, high population growth and export-oriented economics in Vietnam have led to a tremendous intensification of rice production, which in turn has significantly increased the amount of pesticides applied in rice cropping systems. Since pesticides are toxic by design, there is a natural concern on the impact of their presence in the environment on human health and environmental quality. The present study was designed to examine the water regime and fate of pesticides (fenitrothion, dimethoate) during two consecutive rice crop seasons in combined paddy rice-fish pond farming systems in northern Vietnam. Major results revealed that 5 and 41% (dimethoate), and 1 and 17% (fenitrothion) of the applied mass of pesticides were lost from the paddy field to the adjacent fish pond during spring and summer crop seasons, respectively. The decrease of pesticide concentration in paddy surface water was very rapid with dissipation half-life values of 0.3 to 0.8 and 0.2 d for dimethoate and fenitrothion, respectively. Key factors controlling the transport of pesticides were water solubility and paddy water management parameters, such as hydraulic residence time and water holding period. Risk assessment indicates that the exposure to toxic levels of pesticides for aquaculture (, ) is significant, at least shortly after pesticide application.     

Point- and nonpoint-source pesticide contamination in the Zwester Ohm catchment, Germany

Reducing pesticide loads in surface waters implies identifying the pathways responsible for the pollution. The current study documents the pesticide contamination of the river Zwester Ohm, a 4917-ha catchment in Germany with 41% of the land used for crop production. Discharges and concentrations of 19 pesticides were measured continuously at three locations for 15 mo. The load detected at the outlet of the catchment amounted to 9048 g a.i. The losses represent 0.22% of the pesticides applied by the farmers. The contamination showed a seasonal pattern following the pesticide application times. The wastewater treatment plant system (WWTPS) in the catchment (two wastewater treatment plants [WWTP], 14 combined sewer overflows (CSO), four CSO tanks) emits during dry weather periods purified sewage and during storm events sewage mixed with stormwater runoff into the river. The contribution by the WWTPS to the pesticide load was defined as point-source pollution (PSP). The load was dominated by PSP with at least 77% of the total pollution. No significant interdependencies between intrinsic properties of the pesticides, hydrometeorological factors, and the loads occurring in the stream could be found. Therefore, it is not possible to predict PSP for other catchments based on the results from this study. Whereas 65% of the total load entered the river via the WWTP, a portion of 12% was attributed to the CSO. The study points out that the influence of CSO on PSP should be taken into account in future catchment studies in areas with comparable agricultural structure.     

Trends in Pesticide Concentrations in Streamsof the Western United States, 1993‐20051

Johnson, Henry M., Joseph L. Domagalski, and Dina K. Saleh, 2010. Trends in Pesticide Concentrations in Streams of the Western United States, 1993‐2005. Journal of the American Water Resources Association (JAWRA) 00(0):1‐22. DOI: 10.1111/j.1752‐1688.2010.00507.x Abstract: Trends in pesticide concentrations for 15 streams in California, Oregon, Washington, and Idaho were determined for the organophosphate insecticides chlorpyrifos and diazinon and the herbicides atrazine, s‐ethyl diproplythiocarbamate (EPTC), metolachlor, simazine, and trifluralin. A parametric regression model was used to account for flow, seasonality, and antecedent hydrologic conditions and thereby estimate trends in pesticide concentrations in streams arising from changes in use amount and application method in their associated catchments. Decreasing trends most often were observed for diazinon, and reflect the shift to alternative pesticides by farmers, commercial applicators, and homeowners because of use restrictions and product cancelation. Consistent trends were observed for several herbicides, including upward trends in simazine at urban‐influenced sites from 2000 to 2005, and downward trends in atrazine and EPTC at agricultural sites from the mid‐1990s to 2005. The model provided additional information about pesticide occurrence and transport in the modeled streams. Two examples are presented and briefly discussed: (1) timing of peak concentrations for individual compounds varied greatly across this geographic gradient because of different application periods and the effects of local rain patterns, irrigation, and soil drainage and (2) reconstructions of continuous diazinon concentrations at sites in California are used to evaluate compliance with total maximum daily load targets.     

芹菜农药残留监测结果分析

为了解芹菜质量安全现状,对蔬菜批发市场、农贸市场、超市销售的芹菜进行了农药甲胺磷、氧乐果等50项农药的专项抽样调查分析,共抽检芹菜样本213个,通过采用GB2763--2012（食品中农药最大残留限量》进行判定,结果表明：引起芹菜农药残留超标的农药主要为毒死蜱、甲拌磷、多菌灵等,其中由这3种农药引起芹菜超标的比例占农残超标总批次的78．1％,芹菜质量安全状况还需进一步加强。     

OCCURRENCE OF PESTICIDES IN GROUND WATER OF THE OZARK PLATEAUS PROVINCE1

ABSTRACT: Pesticides were detected in ground-water samples collected from 20 springs and nine wells in the Ozark Plateaus Province of Arkansas, Kansas, Missouri, and Oklahoma. From April through September 1993, water samples were collected from 50 shallow domestic wells and 50 springs in the Springfield Plateau and Ozark aquifers and analyzed for 47 pesticides and metabolites. Pesticides were detected in 17 water samples from the Springfield Plateau aquifer and 12 water samples from the Ozark aquifer. Fourteen pesticides were detected, with a maximum of four pesticides detected in any one sample. The most commonly detected pesticides were atrazine (14 detections), prometon (11 detections), and tebuthiuron (seven detections). P, P' DDE, a metabolite of DDT, was detected in water samples from three wells and one spring. The remaining pesticides were detected in three or less samples. The occurrence and distribution of pesticides probably are related to the local land use near a sampling site. Pesticide detections were significantly related to aquifer, site type, and discharge of springs.     

Optimising herbicide dose: a straightforward approach to reduce the risk of side effects of herbicides

Public concern of possible effects of pesticides on human health and the environment has lead to an increased pressure on farmers to optimise their use of pesticides. Reducing pesticide doses below the recommended doses whenever possible is a straightforward approach to reduce the risk of adverse side effects. To adopt this approach decision-making has to be improved. The parameters to consider optimising herbicide doses are: weed flora and growth stage, crop competitiveness, climatic conditions, application technique, formulation/adjuvant and combination with other pesticides. In Denmark this information is provided to farmers through the decision support system ‹Plant Protection Online’. Based on input on weed species and densities, climatic conditions, soil type, crop cultivar and expected yield ‹Plant Protection Online’ will provide farmers with optimum herbicide solution usually with doses lower than standard recommended doses.     

Continuing Issues in the Limitations of Pesticide Use in Developing Countries

The rationale for pesticide use in agriculture is that costs associated with pesticide pollution are to be justified by its benefits, but this is not so obvious. Valuing the benefits by simple economic analysis has increased pesticide use in agriculture and consequently produced pesticide-induced “public ills.” This paper attempts to explore the research gaps of the economic and social consequences of pesticide use in developing countries, particularly with an example of Nepal. We argue that although the negative sides of agricultural development, for example- soil, water, and air pollution; pest resistance and resurgence; bioaccumulation, bio-magnification; and loss of biodiversity and ecosystem resilience caused by the use of pesticides in agriculture, are “developmental problems” and are “unintentional,” the magnitude may be increased by undervaluing the problems in the analysis of its economic returns. Despite continuous effort for holistic system analyses for studying complex phenomena like pesticides impacts, the development within the academic science has proceeded in the opposite direction that might have accelerated marginalization of the third world subsistence agricultural communities. We hypothesize that, if these adversities are realized and accounted for, the benefits from the current use of pesticides could be outweighed by the costs of pollution and ill human health. This paper also illustrates different pathways and mechanisms for marginalization. In view of potential and overall negative impacts of pesticide use, we recommend alternative ways of controlling pests such as community integrated pest management (IPM) along with education and training activities. Such measures are likely to reduce the health and environmental costs of pesticide pollution, and also enhance the capabilities of third world agricultural communities in terms of knowledge, decision making, innovation, and policy change.