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1.
目前使用的绝大多数农药为合成农药,具有急性毒性特征,已开展的慢性评估不能完全符合实际需要,慢性评估结果容易出现过低估计风险,具有急性毒性特征的农药残留必须开展急性评估。为了推进急性评估研究,为我国食品安全监管和残留限量的制定提供技术支持,在WHO原则指导下、基于JMPR建议的方法,开展了蔬菜中氯氰菊酯残留的急性和慢性点评估技术研究。结果显示,济南、青岛和寿光三地市售的西红柿、菜椒、菜豆、茄子、豇豆和芹菜中氯氰菊酯残留摄入是安全的;虽然白菜出现了超标的个例,但99.98%的氯氰菊酯残留摄入不存在危害健康的摄入风险;即使考虑50%的总体误差以及蔬菜占总食物摄入量的比例,至少99.96%的残留摄入不存在危害健康的摄入风险。研究表明,摄入频率高的7类蔬菜中氯氰菊酯残留污染较轻,对消费者(包括孕妇、婴儿和儿童)身体健康危害很小。  相似文献   

2.
Advances in pesticide environmental fate and exposure assessments   总被引:1,自引:0,他引:1  
Globalization of markets and the growing world population increase threats of invasive and exotic species and place greater demands on food and fiber production. Pest management in both agricultural and nonagricultural settings employs established practices and new biological, chemical, and management technologies. Pesticides are an essential tool in integrated pest management. Without pesticides a significant percentage of food and fiber crops would be lost, infectious diseases would increase, and valuable native habitats would be devastated. Therefore, it is important to understand the environmental fate of pesticides and assess their potential exposure and associated risks to human health and the environment. This paper summarizes the Advances in Pesticide Environmental Fate and Exposure Assessment symposium held at the 231st National Meeting of the American Chemical Society (Atlanta, GA, 2006). The focus of the symposium was to provide current information on advances in pesticide environmental fate and exposure assessments. Thirty papers were presented on advances ranging from subcellular processes to watershed-scale studies on topics including chemical degradation, sorption, and transport; improved methodologies; use of modeling and predictive tools; exposure assessment; and treatment and remediation. This information is necessary to develop more effective pesticide use and management practices, to better understand pesticide fate and associated exposures and risks, to develop mitigation and remediation strategies, and to establish sound science-based regulations.  相似文献   

3.
Background, Aims and Scope   Contaminated land is a high priority environmental problem in most of Europe and North-America. Sweden is no exception and generic guideline values have been developed for the initial assessment, but site-specific assessments are also needed. The generic guideline values are not applicable when the exposure conditions are different from the typical Swedish conditions or when the site contains a particularly sensitive ecosystem. The Swedish guideline values have, like in many other countries, been set by using deterministic point estimates for all variables and constants in the used multimedia model. The same approach is common also for site-specific assessments, and a limitation is that it fails to quantify variability and uncertainty. Probabilistic risk assessment provided a method to deal with this problem. Variability and uncertainty in the input parameters (variables or constants) are described by probability distributions, and likewise the output (risk or exposure) is presented as a probability distribution. A substantial number of probabilistic risk assessments for contaminated land at sites in North America, Europe and Asia have been published. However, an extensive review of the literature did not identify any study where probabilistic risk assessment was applied to a site contaminated by an iron or steel industry. Here we will describe such a case, where we have compared a deterministic point estimate with a probabilistic risk assessment for six elements and benzo[a]pyrene. Methods   The site had different metallurgical plants in operation for more than 100 years. Most parts of the steel mill were closed by the mid 1980s, and today the site is used by small-sized enterprises. The soil is contaminated with metals from the previous industrial operations. The present owner plans to develop the site and has therefore initiated extensive investigations of soil contamination. Sixty-two soil samples collected between 1997 and 2000 provided a good coverage of the whole site, and were analyzed for the content of different elements and polycyclic aromatic hydrocarbons (PAH). The exposure assessments were focused on six elements with high concentrations compared to the generic guideline values; arsenic (As), lead (Pb), cadmium (Cd), chromium (Cr), copper (Cu) and zinc (Zn). In addition, benzo[a]pyrene was included due to the high toxicity and comparatively high concentrations. Variability and uncertainty were characterized in a Monte Carlo simulation of exposures (10 000 iterations), and the exposures were evaluated with two land use scenarios; less sensitive use and sensitive use. Results and Discussion   The deterministic point estimates and the probabilistic estimates of the 95th percentile are in approximately the same ranges in the scenario of less sensitive land use. It is only the exposure for arsenic that is slightly above the toxicological reference value (TRV) in the deterministic assessment. In the probabilistic assessment, the exposure for all elements is below the TRV. The results for sensitive land use are applicable to a scenario where the site is developed for general housing. The deterministic point estimates and the probabilistic estimates of the 95th percentile are also here in approximately the same ranges, but the exposure exceeds the TRV for arsenic, cadmium and lead. Drinking water, vegetables grown on site and soil ingestion are the major exposure pathways for this scenario. In this assessment, the estimated intake distributions are applicable to a randomly selected individual. The probability distributions used here to characterize the different soil parameters are typically representing both variability and uncertainty, and the same is true the majority of the exposure variables. We therefore decided not to attempt to separate variability and uncertainty at this stage, but with additional data from a more in-depth site investigation it might be possible to achieve this. Conclusions and Outlook   To the best of our knowledge, this study is the first report on a probabilistic risk assessment on a former iron and steel works site. The materials handled by this industry were less toxic than for many other metallurgical operations, but contaminants may still severely limit the options for future land use. This case study shows that probabilistic exposure estimates for a set of soil contaminants can be quite similar to deterministic point estimates. The main difference is instead to be found in the additional information obtained with the probabilistic assessment. The sensitivity analyses show pathways and input variables that contribute most to variations in the total intake of each contaminant, e.g. dermal contact and ingestion of soil, vegetables and drinking water. This information can be used both in the planning of future land use and for active measures to reduce current exposure. The probabilistic assessment also provides information on the magnitude of exposure and the margin of safety. This information may facilitate risk communication between decision-makers and stakeholders. The presentation of results from probabilistic risk assessments is only briefly discussed in the literature and here we see a need for research and opportunities for enhancement. The choice of data analytical tools may then be of importance, since more complex multimedia models are rather difficult to decipher when implemented within traditional spreadsheet software. Some of the research needs are identified here and in a previous review article in this journal.  相似文献   

4.
为了解我国西北地区蔬菜水果和食用菌的质量安全情况及暴露风险,本试验从2018至2020年在我国甘肃省平凉市进行样品抽取,共测定2 435份蔬菜水果和食用菌样品中46种农药残留的含量.通过农药残留风险评估方法分析了 9类别蔬菜水果和食用菌中农药残留的分布和相关性,并对蔬菜和水果中农药残留情况进行了风险排序,以及暴露风险、...  相似文献   

5.
During a 5 year period from 1982 to 1986, the FDA Los Angeles District Laboratory analyzed 19,851 samples of domestic and imported food and feed commodities for pesticide residues. A single, rapid, multiresidue method was used. The resultant data have been compiled showing the commodities sampled and the identity and range of levels of pesticide residues detected, including an indication of those residue findings that did not comply with U.S. federal tolerance levels. The residue data presented should not be viewed as being representative of the U.S. food supply; rather, the results are indicative of a surveillance- and compliance-oriented sampling of various food shipments collected by the Los Angeles District.  相似文献   

6.
Methods to refine the assessment of exposure of wild birds and mammals to pesticides required measurement of pesticide residues in very small samples of their diets. Sample sizes were in the 1-100 mg range, and the target residue for measurement was 0.01 mg/kg. Gas chromatography-mass spectrometry (GC-MS) with large volume injection was compared with the use of an accelerator mass spectrometer (AMS) to measure residues of pesticide labeled at near-background levels with carbon-14. The GC-MS method was able to detect residues down to 0.1 ng per item of diet, and the AMS detected the radiolabel down to 1 mBq (0.06 disintegration per minute, 1 ng of pesticide at the specific activity used) per sample. The target residue level was achieved by the GC-MS method for samples down to 10 mg. The GC method appeared to be best suited to monitoring residues in field studies, and the AMS shows great potential for use in laboratory experiments concerning pesticide degradation.  相似文献   

7.
There has been interest within the pesticide regulatory community in developing a tool that can provide estimates of potential pesticide exposure in shallow groundwater across an intended use area. Therefore, industry initiated an investigative project based on the PRZM 3.12 model, which uses regional soils and weather in an easy to use interface. The goal of this proof-of-concept is to facilitate the refinement of groundwater exposure estimates. The focus of this paper is to report the effectiveness of the tool as a regional estimator of potential groundwater contamination.  相似文献   

8.
The extent to which bystanders are exposed to pesticide applications is unknown. Systematic monitoring around spray areas is not routine. Quantifying exposures is extremely difficult. Persons inadvertently exposed to pesticides often do not know the chemical or quantity, and persons living near areas of frequent field spraying may receive multiple exposures. In the U.S., concerns about health consequences from these exposures may prompt calls to poison control centers. The goal of this study was to determine what surveillance poison control centers can provide on environmental pesticide exposures to bystanders. We searched the American Association of Poison Control Centers' 2001 electronic medical records for exposure reports involving persons from 129 agriculturally intensive counties in Kentucky, Tennessee, Louisiana, and Arkansas that implicated at least one of 54 generic classifications of agricultural chemicals. We abstracted 980 pesticide-related records. Narrative sections were reviewed to determine bystander status of the exposed person. Forty-six bystander exposures were identified from 32 events. Bystander ages ranged from 2 to 81 (median: 45; 16 females, 13 males). All pertinent information for bystander classification came from narrative sections of the record. 28% identified aircraft crop dusters as the pesticide source. The most implicated substance was malathion (30.4%), while 19.6% did not know the exposure substance. 73.9% of cases were symptomatic; 65.2% of the exposed persons were seen in or referred to a healthcare facility. No hospitalizations or deaths were reported. Although they may underestimate the true numbers, U.S. poison control center data can provide valuable information about bystander environmental pesticide exposures.  相似文献   

9.
农产品中农药残留分析技术研究进展   总被引:1,自引:0,他引:1  
农药残留的极性中毒事件和农产品进出口贸易中农药残留超标问题时有发生,农药残留分析是保证人民群众食品安全和进出口企业利益的重要手段,近年来农产品中农药残留分析技术有了快速的发展。本文主要在农药残留分析中的样品前处理和仪器检测2方面对近5年来的研究进展进行分析和讨论,主要探讨了前处理中的QuEChERS方法的应用、改进和发展,以及仪器检测手段中串联质谱的应用现状及高分辨质谱的应用前景,最后对农药残留分析这两方面的发展进行了展望。  相似文献   

10.
Since the discovery of acrylamide in foods, there have been many calculations of dietary exposure. Total diet studies have been commonly used to estimate consumer exposure of acrylamide; however, these often fall short in evaluating true exposure levels because of limitations in small occurrence data sets. Dietary exposure to acrylamide can also be estimated by use of modeling packages. The U.K. Food Standards Agency and the Food Safety Authority of Ireland have prepared estimates for dietary acrylamide exposure using semiprobabilistic and probabilistic modeling. Occurrence data were obtained from the European Union acrylamide monitoring database, whereas consumption data were obtained from the relevant U.K. and Irish National Diet and Nutrition Surveys. The mean adult U.K. consumer exposure was estimated as 0.61 microg/kg of body weight (bw)/day and high-level adult consumer exposure (P97.5) as 1.29 microg/kg of bw/day. The mean adult Irish consumer exposure was estimated as 0.59 microg/kg of bw/day and the high-level adult consumer exposure (P97.5) as 1.75 microg/kg of bw/day. Owing to the wide range of acrylamide levels in foods, semiprobabilistic modeling does not always provide an accurate picture of dietary exposure levels and patterns. Therefore, a comparison of semiprobabilistic assessments to probabilistic assessments of U.K. and Irish dietary exposure estimates of certain food groups is provided.  相似文献   

11.
This investigation was initiated as a result of proposals in the literature that dietary nicotine intake could contribute to the level of nicotine metabolites in biological fluids such as salivary cotinine concentration. Nicotine concentration was determined in several frequently consumed vegetables from the nightshade family (Solanaceae) (i.e., tomatoes, potatoes, aubergines, and peppers), as well as in some of their processed products. The edible Solanaceae fruit analyzed in this investigation were found to contain relatively consistent amounts of nicotine in the range of 2-7 microg/kg for fresh fruits. Nevertheless, the nicotine concentrations of the investigated tomato varieties decreased significantly with increasing degree of ripening of the fruits. In addition, a variety of black as well as green teas was investigated for the nicotine content. Nicotine content in tea leaves was found to be highly variable and sometimes much larger than in the Solanaceae fruits. On the basis of the observed concentrations and the respective food consumption data for different countries, a distributive analysis of the results suggests that the mean daily dietary nicotine intake for the population of the countries for which consumption data were available is approximately 1.4 microg/day, 2.25 microg/day at the 95th percentile.  相似文献   

12.
Evidence for substantial environmental influences on health and food safety comes from work with environmental health indicators which show that agroenvironmental practices have direct and indirect effects on human health, concluding that "the quality of the environment influences the quality and safety of foods" [Fennema, O. Environ. Health Perspect. 1990, 86, 229-232). In the field of genetically modified organisms (GMOs), Codex principles have been established for the assessment of GM food safety and the Cartagena Protocol on Biosafety outlines international principles for an environmental assessment of living modified organisms. Both concepts also contain starting points for an assessment of health/food safety effects of GMOs in cases when the environment is involved in the chain of events that could lead to hazards. The environment can act as a route of unintentional entry of GMOs into the food supply, such as in the case of gene flow via pollen or seeds from GM crops, but the environment can also be involved in changes of GMO-induced agricultural practices with relevance for health/food safety. Examples for this include potential regional changes of pesticide uses and reduction in pesticide poisonings resulting from the use of Bt crops or influences on immune responses via cross-reactivity. Clearly, modern methods of biotechnology in breeding are involved in the reasons behind the rapid reduction of local varieties in agrodiversity, which constitute an identified hazard for food safety and food security. The health/food safety assessment of GM foods in cases when the environment is involved needs to be informed by data from environmental assessment. Such data might be especially important for hazard identification and exposure assessment. International organizations working in these areas will very likely be needed to initiate and enable cooperation between those institutions responsible for the different assessments, as well as for exchange and analysis of information. An integrated assessment might help to focus and save capacities in highly technical areas such as molecular characterization or profiling, which are often necessary for both assessments. In the area of establishing international standards for traded foods, such as for the newly created Standards in Trade and Development Facility (STDF), an integrated assessment might help in the consideration of important environmental aspects involved in health and food safety. Furthermore, an established integrated view on GMOs may create greater consumer confidence in the technology.  相似文献   

13.
To estimate variations in pesticide residue levels in crops, the variability factors (VFs, the 97.5th percentile of the residue levels in the sample divided by the average residue levels in the lot) in residue levels of acetamiprid and cypermethrin applied to cabbage and grapes were investigated, respectively. The VFs in the residue levels of both pesticides in cabbage (2.00 and 2.39, respectively) were clearly higher than those in grapes (1.82 and 1.63, respectively). Although the residue levels of both pesticides in grapes showed a normal distribution, those values in cabbage were slightly skewed at lower residue levels. Individual residue levels in grapes had a good agreement between acetamiprid and cypermethrin. In contrast, the distribution of cypermethrin residue levels in cabbage was slightly skewed at higher residue levels as compared to that of acetamiprid. These results indicate that the difference in the relative distribution of the two pesticides between cabbage and grapes might be due to the influence of various factors such as differences in crop species, plant cultivation methods, and physicochemical properties of the pesticides.  相似文献   

14.
The U.S. Food and Drug Administration (FDA) has carried out a large-scale monitoring program for pesticide residues in foods since the 1960s. The program has evolved continuously as evidenced by a number of recently incorporated modifications and initiatives. Included are greater emphasis on imports; increased and more specific targeting of pesticide/commodity combinations by geographic area or country; development of individual district sampling plans for domestic and imported foods; expanded use of single residue methods; linkage of information on foreign pesticide usage with food import volumes; development of an analytical methods research plan; and increased cooperative sampling and data exchange with the states. Initiatives to acquire and utilize private sector and other monitoring data are being explored, and aggressive steps are being taken to inform the public of FDA monitoring results in a timely and understandable manner.  相似文献   

15.
表面增强拉曼光谱检测脐橙果皮混合农药残留   总被引:4,自引:2,他引:2  
为了研究果皮农药残留快速检测方法。该文以脐橙为例,混合农药(亚胺硫磷和乐果)为研究对象,选用银纳米线作为增强基底,利用共焦显微拉曼光谱仪对农药残留进行检测。通过表面增强拉曼光谱(surface enhanced Raman scattering,SERS)技术,采集脐橙表皮混合农药残留的SERS光谱。对混合农药定性分析,银纳米线对2种农药都有较好的增强效果。对采集的光谱进行预处理后,建立模型,进行定量分析,研究结果表明,经过二阶微分预处理后光谱数据结合偏最小二乘法(partial least squares,PLS)得到的模型预测效果最好,预测相关系数(R_p)为0.954,其预测均方根误差(root-mean-square prediction error,RMSEP)为4.822 mg/L。挑选两种农药特征峰的特征波段,混合农药中亚胺硫磷的特征波段经多元散射校正(multiplicative scatter correction,MSC)处理后,建模效果较好,其中R_p为0.898,RMSEP为6.621 mg/L;混合农药中乐果的特征波段经基线校正处理后,建模效果较好,其中R_p为0.911,RMSEP为7.369 mg/L。研究结果表明SERS技术是一种快速、可靠的检测混合农药残留的方法。  相似文献   

16.
Uncertainties in exposures can lead to biased estimates of slopes and thresholds in the exposure-response relationships that are developed from regression analysis. This paper reviews published exposure and epidemiological studies of methylmercury (MeHg) from the perspective of the accuracy and precision of the estimates used to represent the actual doses received. Sources of such uncertainties, collectively referred to as “exposure errors”, include instrumental and analytical errors, sampling and survey uncertainties, and individual variability in the relationships between the exposure metrics and the actual doses to target organs. Because the relationship between maternal intake and the consequent dose to the fetal brain varies among individuals, epidemiological studies of the effects of prenatal exposure must necessarily be accompanied by larger exposure uncertainties than comparable studies of effects on the mothers. The increased exposure errors typically result in attenuated slopes of the dose-response functions and under-estimates of thresholds, so that part of the apparent increased sensitivity of the fetus that has been developed from epidemiological studies may in fact be due to their inherently less certain exposures. Sources and magnitudes of exposure error found in the literature are discussed and their statistical ramifications are explored with Monte Carlo simulations. The paper also finds that, after adjusting for exposure error, the relationship between dietary intake and blood concentration is consistent with an average half-life shorter than has typically been used and that using population averages yields a consistent but sub-linear relationship between dietary intake of Hg and hair concentration. Investigators are urged to obtain (and present) data on more than one exposure metric, so that their relative uncertainties may be assessed independently.  相似文献   

17.
This study presents concentrations of perfluorinated compounds in food and the dietary intake of perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) in The Netherlands. The concentrations of perfluorinated compounds in food were analyzed in pooled samples of foodstuffs randomly purchased in several Dutch retail store chains with nation-wide coverage. The concentrations analyzed for PFOS and PFOA were used to assess the exposure to these compounds in The Netherlands. As concentrations in drinking water in The Netherlands were missing for these compounds, conservative default concentrations of 7 pg/g for PFOS and 9 pg/g for PFOA, as reported by European Food Safety Authority, were used in the exposure assessment. In food, 6 out of 14 analyzed perfluorinated compounds could be quantified in the majority of the food categories (perfluoroheptanoic acid (PFHpA), PFOA, perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoro-1-hexanesulfonate (PFHxS), and PFOS). The highest concentration of the sum of these six compounds was found in crustaceans (825 pg/g product, PFOS: 582 pg/g product) and in lean fish (481 pg/g product, PFOS: 308 pg/g product). Lower concentrations were found in beef, fatty fish, flour, butter, eggs, and cheese (concentrations between 20 and 100 pg/g product; PFOS, 29-82 pg/g product) and milk, pork, bakery products, chicken, vegetable, and industrial oils (concentration lower than 10 pg/g product; PFOS not detected). The median long-term intake for PFOS was 0.3 ng/kg bw/day and for PFOA 0.2 ng/kg bw/day. The corresponding high level intakes (99th percentile) were 0.6 and 0.5 ng/kg bw/day, respectively. These intakes were well below the tolerable daily intake values of both compounds (PFOS, 150 ng/kg bw/day; PFOA, 1500 ng/kg bw/day). The intake calculations quantified the contribution of drinking water to the PFOS and PFOA intake in The Netherlands. Important contributors of PFOA intake were vegetables/fruit and flour. Milk, beef, and lean fish were important contributors of PFOS intake.  相似文献   

18.
Exposure of golfers to pesticides following their application to turfgrass is of concern to regulators, turfgrass professionals, and consumers. Multipathway exposures were evaluated for golfers on turfgrass treated with chlorpyrifos and carbaryl. Air concentrations and transferable foliar residues (TFRs) were measured to assess potential respiratory and dermal exposures, respectively. At the same time, exposure to individuals simulating the play of golf was determined by dosimetry and urinary biomonitoring. Individual golfer exposure was determined in 76 rounds of golf following eight applications of chlorpyrifos and two applications of carbaryl. Estimated exposures to golfers following full course and full rate applications of chlorpyrifos and carbaryl were 19-68 times below current U.S. EPA acute reference dose (Rfd) values, indicating safe exposures under U.S. EPA hazard quotient criteria. Dermal exposure was determined to be the dominant exposure pathway to golfers, accounting for approximately 60% of the chlorpyrifos absorbed dose and 100% of the carbaryl absorbed dose. This study also provides a set of transfer factors (TFs) that may be used to determine dermal exposure of golfers to pesticides using transferable residue data.  相似文献   

19.
Recent legislation in the European Union requires regulators of member states to carry out risk assessments using data for actual or potential operator exposure, or estimates of exposure from models. However, the existing models have few datasets from studies carried out on greenhouse or indoor crops, particularly in southern Europe. In this study potential dermal and inhalatory exposures were measured in two trials in Italian greenhouses. The total potential dermal operator exposure of the applicator, measured with a whole-body passive dosimetry method, was 15.4 and 37.1 mL/h of the diluted pesticide mixture. The majority of the contamination was on the hands and on the lower part of the coverall. Approximately 0. 003% of the active ingredient (ai) applied to the crop area contaminated the coverall worn by the operator. The potential dermal exposure during the mixing and loading phase accounted for 6-8% of the total potential dermal exposure during the whole process. Inhalation exposure accounted for only 0.05-0.07% of the total potential operator exposure. Model predictions of the potential operator exposure using a modified version of the German model overestimate the mixing-loading exposure while underestimating the application exposure. These data are evidence that the estimation coefficient set for hand-held application to ornamental and horticultural crops may be inadequate for the agronomic conditions of southern Europe.  相似文献   

20.
Phytoestrogens are secondary plant metabolites that have received increasing attention for their bioactivity, in particular due to their structural and functional similarity to 17beta-estradiol. Although urinary and plasma phytoestrogens can be used as biomarkers for dietary intake, this is often not possible in large epidemiological studies or in the assessment of general exposure in free-living individuals. Accurate information about dietary phytoestrogens is therefore important, but there are very limited data concerning food contents. In this study was analyzed a comprehensive selection of tea, coffee, alcoholic beverages, nuts, seeds, and oils for their phytoestrogen content using a newly developed sensitive method based on LC-MS incorporating (13)C 3-labeled standards. Phytoestrogens were detected in all foods analyzed, although the contents in gin and bitter (beer) were below the limit of quantification (1.5 microg/100 g). Lignans were the main type of phytoestrogens detected. Tea and coffee contained up to 20 microg/100 g phytoestrogens and beer (except bitter) contained up to 71 microg/100 g, mainly lignans. As these beverages are commonly consumed, they are a main source of dietary lignans. The results published here will contribute to databases of dietary phytoestrogen content and allow a more accurate determination of phytoestrogen exposure in free-living individuals.  相似文献   

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