Dissipation,residues, and risk assessment of imidacloprid in Zizania latifolia and purple sweet potato under field conditions using LC-MS/MS

A shortened version of Quick, Easy, Cheap, Effective, Rugged, and Safe method (QuEChERS) for determining the dissipation and residue of imidacloprid present in Zizania latifolia and purple sweet potato was established by using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The average recoveries of imidacloprid in the two crops ranged from 82.12 to 113.79%, with relative standard deviation (RSD) of <7.32%. The dissipation dynamics of imidacloprid in Z. latifolia plants and purple sweet potato plants followed first-order kinetics, with half-lives of 3.2–5.5?days in each of sampling locations. The terminal imidacloprid residues in Z. latifolia and purple sweet potato at each of location were <0.005–0.120?mg kg^?1. According to the risk assessment results, both the acute dietary risk quotient and chronic dietary risk quotient values were <1, indicating that imidacloprid is unlikely to pose health risks to humans with normal recommended use. The present study may serve as a valuable reference for the safe and reasonable use of imidacloprid in Z. latifolia and purple sweet potato fields.     

Comprehensive estimate of the theoretical maximum daily intake of pesticide residues for chronic dietary risk assessment in Argentina

A chronic dietary risk assessment for pesticide residues was conducted for four age groups of the Argentinian population following the procedure recommended by the WHO. The National Theoretical Maximum Daily Intake (NTMDI) for 308 pesticides was calculated for the first time, using the Maximum Residue Limits (MRLs) from several Argentinean regulations and food consumption data from a comprehensive National Nutrition and Health Survey. The risk was estimated by comparing the TMDI with the Acceptable Daily Intakes (ADI) identified by various sources. Furthermore, for each of the compounds with a TMDI >65% of the ADI, a probabilistic analysis was conducted to quantify the probability of exceeding the ADI. In this study 27, 22, 10, and 6 active ingredients (a.i.) were estimated to exceed the 100% of the ADI for the different population groups: 6–23 month-old children, 2–5 year-old children, pregnant women, and 10–49 year-old women, respectively. Some of these ADI-exceeding compounds (carbofuran, diazinon, dichlorvos, dimethoate, oxydemeton-methyl and methyl bromide) were found in all four of these groups. Milk, apples, potatoes, and tomatoes were the foods that contributed most to the intake of these pesticides. The study is of primary importance for the improvement of risk assessment, regulations, and monitoring activities.     

Determination of the residue dynamics and dietary risk of thiamethoxam and its metabolite clothianidin in citrus and soil by LC-MS/MS

A modified quick, easy, cheap, effective, rugged and safe (QuEChERS) method was developed for the determination of thiamethoxam and its metabolite clothianidin in citrus (including the whole citrus, peel and pulp) and soil samples by liquid chromatography-tandem mass spectrometry. The sample was extracted with acetonitrile and purified with octadecylsilane. The detection limits of both compounds were 0.0001–0.0002?mg kg^–1, while the limit of quantification of thiamethoxam was 0.002?mg kg^–1 and the limit of quantitation of metabolites was 0.001?mg kg^–1. The recovery was 70.37%–109.76%, with inter-day relative standard deviations (RSD) (n?=?15) values ≤9.46% for the two compounds in the four matrices. The degradation curve of thiamethoxam in whole citrus and soil was plotted using the first-order kinetic model. The half-life of the whole citrus was 1.9–6.2?days, and the half-life of the soil was 3.9–4.2?days. The terminal residue of thiamethoxam (the sum of thiamethoxam and clothianidin, expressed as thiamethoxam) was found to be concentrated on the peel. The final residual amount of thiamethoxam in the edible portion (pulp) was less than 0.061?mg kg^–1. The risk quotient values were all below 1, indicating that thiamethoxam as a citrus insecticide does not pose a health risk to humans at the recommended dosage.     

Hazard identification and risk assessment procedure for genetically modified plants in the field--GMHAZID

The safe application of genetically modified organisms (GMOs) requires a risk assessment prior to their proposed use. Based on methods from the chemical industry, we developed a hazard identification procedure for the risk assessment of field tests with genetically modified plants. This risk assessment method, GMHAZID, is carried out in the form of guided brainstorm sessions. GMHAZID was tested with a case study for which a risk assessment had previously been made, and the results of the assessments were compared. The results showed that some new hazards potentially leading to uncontrolled spreading, in addition to those from the previous assessment, were identified using GMHAZID. GMHAZID also recognised some hazards leading to failures in the field experiments. We suggest that GMHAZID provides systematics, reliability, and transparency to the risk assessment procedure.     

National short-term dietary exposure assessment of a selected group of pesticides in Argentina

ABSTRACT

An evaluation of acute dietary exposure to pesticide residues, applying deterministic and stochastic methods, was performed for a selected group of pesticides in two representative age groups from Argentina. Thus, 28 active ingredients (a.i.) and 75 food items were evaluated for the group of 2–5-year-old children, while 9 a.i. and 59 food items were considered for the 10–49-year-old women group. A deterministic assessment was conducting following the Food and Agriculture Organization (FAO) and World Health Organization (WHO) procedure but using the national maximum residue limits (MRLs) as pesticide residue concentration data, while in the stochastic approach, a theoretical distribution modeled with the available information was used. Food consumption data were obtained from the 2004–2005 comprehensive national nutrition and health survey. The risk was estimated by comparing the short-term dietary exposure with the acute reference dose (ARfD) values for each pesticide-food combination evaluated. In the deterministic assessment, 173 (39.1%) and 40 (31.3%) combinations exceeded the ARfD thresholds for the 2–5-year-old children and 10–49-year-old women groups, respectively. This conservative study generated relevant information as a first stage of acute dietary risk assessment in Argentina.     

舟山近岸海域贝类中有机氯农药残留水平及人体健康风险评估

于2012年的7月在舟山群岛新区的海域采集贝类样本,测定了其中的有机氯农药残留量,并进行了人体健康风险评估和安全食用量推算。结果表明,采集的5种贝类样本中,六六六(BHCs)的各组分均未被检出,而滴滴涕(DDTs)在各种样本中均有检出,其中僧帽牡蛎和部分縊蛏样本中DDTs总量超过《海洋生物质量标准》(GB 18421—2001)一类标准(10μg/kg);健康风险评估结果显示,贝类样本中α-BHC、β-BHC、γ-BHC、p,p’-滴滴伊(p,p’-DDE)、p,p’-滴滴滴(p,p’-DDD)、p,p’-DDT的总致癌风险指数均低于10-4,致癌风险均在可接受的安全范围,α-BHC、β-BHC、γ-BHC、p,p’-DDE的总接触风险指数均小于1,接触风险指数未超过危害剂量参考值,人体食用舟山近岸海域的贝类是安全的;按可接受的致癌风险指数进行评估,人体的贝类安全消费量为9.8~138.0g/(kg·d)(按体重计,下同),而按可接受的接触风险指数进行评估,人体的贝类安全消费量在24.6~235.0g/(kg·d)。     

邵阳市城区大气降尘中的Pb、Cd的污染及环境风险评价

为研究邵阳市城区大气降尘中Pb、Cd的污染程度及环境风险,于2011—2014年在不同功能区采集大气降尘样品,对Pb、Cd的污染程度及环境风险进行评价。结果表明,邵阳市城区大气降尘中Pb、Cd平均值分别为167.29、2.09mg/kg;各功能区大气降尘中Pb的年平均值污染程度级别在2~3级,城区的年平均值污染程度为中度污染,Cd在各个功能区及城区的年平均值污染程度级别均为4级,属于强污染;各功能区Pb、Cd的潜在生态风险指数波动较小,Pb均为轻微生态危害,Cd均为极强生态危害;城区大气降尘中Pb、Cd的总非致癌风险为儿童6.90×10-1、成年女性9.59×10-2、成年男性8.26×10-2;Cd的呼吸系统吸入途径平均致癌风险为成年女性5.42×10-9、成年男性为5.15×10-9,远低于10-6~10-4,不具有致癌风险。     

Risk assessment of conventional crop plants in analogy to transgenic plants

The risk assessment of genetically-modified plants pursuant to Annex II B of EU Directive 94/15/EC assumes that it is possible to infer the environmental impacts of a crop plant from its characteristics, so most of Annex II should also be applicable to conventional plants. To test this, we surveyed reports on the ecological impacts of the cultivation of non-transgenic crop plants with novel or improved traits and, in three cases, investigated whether Annex II B would have been adequate to indicate the effects. Such an assessment appears to be feasible only if the time frame on which it is based is short, so that long-term effects cannot be assessed. Secondly, the plant must be genetically homogenous which is not always granted, e.g. with forest-trees. Thirdly, the cultivation area must be defined. Differences in the behaviour of foreign plants between their original and cultivation habitats may be ecologically relevant and should be assessed. In the (few) cases where direct inference of the observed effects was possible from inherent traits, these effects often correlated with poor adaptation to local environmental conditions. The ecological impacts of traits that had been introduced in order to overcome poor adaptation may differ widely according to the way in which the traits are exploited. In practice, the effects of agricultural measures are more important than the effects of gene transfer and invasiveness, although the latter currently play a major role in risk assessment. In the light of these deliberations, a modification of Annex II B of EU Directive 94/15/EC is suggested.     

Analysis of chlorothalonil and degradation products in soil and water by GC/MS and LC/MS

We present a method using gas chromatography (GC) and liquid chromatography (LC) coupled to a mass selective detector to measure concentrations of the fungicide chlorothalonil and several of its metabolites in soil and water. The methods employed solid-phase extraction using a hydrophobic polymeric phase for the isolation of analytes. In lake water, average analyte recoveries ranged from 70% to 110%, with exception of pentachloronitrobenzene that gave low recoveries (23%). The method detection limits were determined to be in the range of 1 and 0.1microg l(-1) for the LC and GC methods, respectively. In soil samples, recoveries ranged from 80% to 95% for 4-hydroxy-2,5,6-trichloroisophthalonitrile (metabolite II) and 1,3-dicarbamoyl-2,4,5,6-tetrachlorobenzene (metabolite III). Limits of detection (LOD) were 0.05 and 0.02microg g(-1), respectively. Chlorothalonil and other metabolites were analyzed by GC giving recoveries ranging from 54% to 130% with LOD of 0.001-0.005microg g(-1).     

Environmental and human health risk assessment of organic micro-pollutants occurring in a Spanish marine fish farm

In this work the risk posed to seawater organisms, predators and humans is assessed, as a consequence of exposure to 12 organic micro-pollutants, namely metronidazole, trimethoprim, erythromycin, simazine, flumequine, carbaryl, atrazine, diuron, terbutryn, irgarol, diphenyl sulphone (DPS) and 2-thiocyanomethylthiobenzothiazole (TCMTB). The risk assessment study is based on a 1-year monitoring study at a Spanish marine fish farm, involving passive sampling techniques. The results showed that the risk threshold for irgarol concerning seawater organisms is exceeded. On the other hand, the risk to predators and especially humans through consumption of fish is very low, due to the low bioconcentration potential of the substances assessed.     

利用AQUATOX模型评价淀山湖二氯甲烷生态风险

淀山湖地处上海的饮用水源地,水体中有机污染物的生态风险逐渐引起人们的重视。淀山湖水质监测结果显示,淀山湖中的挥发性有机物以二氯甲烷为主。应用美国环境保护署的AQUATOX模型对淀山湖水体中二氯甲烷进行模拟,并进行生态风险评价,旨在构建基于AQUATOX模型的水环境中有机物浓度模拟方法及风险评价的研究体系。结果显示,淀山湖中的二氯甲烷尚处于安全范围,但是需要加强观测,避免高风险的发生。     

淮河沉积物中重金属污染及潜在生态危害评价

测定了淮河 (江苏段 )表层沉积物中重金属的含量 ,分析了重金属的含量分布及富集状况 ,采用 Lars Hakanson潜在生态危害指数法对重金属的生态危害进行了评价。结果表明 ,各种重金属的含量分布呈现出相似的特点 ,即安徽省进入江苏省境内断面 (肖嘴 )时含量较低 ;在江苏省盱眙县城内断面 (淮河大桥 )含量明显增高 ;汇入洪泽湖前断面 (红光化工厂 )稍高于肖嘴断面。从富集系数来看 ,Pb的富集程度最高 ,其次是 As、Cr、Cd、Zn、Cu;而 Hg的富集程度最低。重金属的潜在生态危害评价显示 ,除淮河大桥断面 Cd的污染属于中等生态危害外 ,其他各点重金属的生态危害都很轻微 ,污染程度顺序为 Cd>As>Hg>Pb>Cu>Zn。     

Polychlorinated biphenyls (PCBs) in marine fishes from China: Levels, distribution and risk assessment

Muscle tissues of large yellow croakers (Pseudosciaena crocea) and sliver pomfret (Pampus argenteus) from nine coastal cities of East China including Dalian, Tianjin, Qingdao, Shanghai, Zhoushan, Wenzhou, Fuzhou, Quanzhou and Xiamen were analyzed for polychlorinated biphenyl (PCB) concentrations. Thirty-six PCB congeners were quantified in the fishes, of which 11 congeners were dioxin-like PCBs. The total PCB concentrations of the present study were at the low end of the global range, which may be related to the smaller usage and shorter consumption history of PCBs in China. PCBs 18, 29, 52, 66, 101, 104, 138, 153, 180 and 194 were the major constituents found in the fish samples. Regression analysis showed a strong positive correlation (R² = 0.800; p < 0.001) between total dioxin-like PCBs and total PCB concentrations, and that total PCB concentrations explain 80% of the variability in total dioxin-like PCB concentrations. Among the species investigated, significantly higher concentrations of total PCBs were found in croakers than in pomfrets, which may be attributed to their different feeding and living habits. No significant difference in total PCB concentrations among the cities was observed; principal component analysis (PCA) of PCB profiles indicated that PCB pollution came from similar sources in the sampling areas and that there may be other PCB sources in Dalian and Wenzhou. The calculated carcinogenic risks (CRs) from the two species based on a low consumption group and high consumption group were all greater than 10⁻⁶, suggesting that daily exposure to dioxin-like PCBs via fish consumption results in a lifetime cancer risk of greater than one in one million. In contrast, the hazard quotients (HQs) of noncancer risks were all less than unity.     

渤海南部表层沉积物重金属污染及潜在生态风险评价

利用电感耦合等离子体/质谱仪(ICP/MS)测定了渤海南部21个站位表层沉积物中Cr、Cu、Zn、Cd和Pb共5种重金属浓度,比较分析了重金属来源及分布特征,同时应用Hakanson潜在生态危害指数法进行潜在生态风险评价.结果表明,调查区域沉积物中Cr、Cu、Zn、Cd、Pb的平均质量浓度分别为43.67、17.27、...     

Environmental risks of chemicals and genetically modified organisms: a comparison. Part II: Sustainability and precaution in risk assessment and risk management

The principles of precaution and sustainability require more consideration in the assessment of environmental risks posed by chemicals and genetically modified organisms. Instead of applying risk reduction measures when there are serious indications for damage, full scientific certainty is often waited for before taking action. The precautionary principle particularly should be applied in those cases in which the extent and probability of damage are uncertain, e.g. in the case of persistent chemicals which are additionally bioaccumulative or highly mobile. Based on these principles, environmental action targets for risks associated with GMOs and chemicals can be developed. Risk management not only includes statutory measures but also instruments designed to influence behaviour indirectly are important to achieve the goals. Particularly for risks of GMOs which provoke fear, risk communication is important. Some rules to which attention should be paid in communication with the public are presented.     

Pollution characteristics and environmental risk assessment of typical veterinary antibiotics in livestock farms in Southeastern China

Scientific interest in pollution from antibiotics in animal husbandry has increased during recent years. However, there have been few studies on the vertical exposure characteristics of typical veterinary antibiotics in different exposure matrices from different livestock farms. This study explores the distribution and migration of antibiotics from feed to manure, from manure to soil, and from soil to vegetables, by investigating the exposure level of typical antibiotics in feed, manure, soil, vegetables, water, fish, and pork in livestock farms. A screening environmental risk assessment was conducted to identify the hazardous potential of veterinary antibiotics from livestock farms in southeast China. The results show that adding antibiotics to drinking water as well as the excessive use of antibiotic feed additives may become the major source of antibiotics pollution in livestock farms. Physical and chemical properties significantly affect the distribution and migration of various antibiotics from manure to soil and from soil to plant. Simple migration models can predict the accumulation of antibiotics in soil and plants. The environmental risk assessment results show that more attention should be paid to the terrestrial eco-risk of sulfadiazine, sulfamethazine, sulfamethoxazole, tetracycline, oxytetracycline, chlorotetracycline, ciprofloxacin, and enrofloxacin, and to the aquatic eco-risk of chlorotetracycline, ciprofloxacin, and enrofloxacin. This is the first systematic analysis of the vertical pollution characteristics of typical veterinary antibiotics in livestock farms in southeast China. It also identifies the ecological and human health risk of veterinary antibiotics.     

某电子垃圾拆解园周边农田土壤中多环芳烃的污染特征及风险评估

研究了某电子垃圾拆解园周边151个农田土壤样品中16种多环芳烃(PAHs)的污染特征和环境风险。结果表明,125个表层土壤样品中PAHs总质量浓度在149.0~2.0×104μg/kg,均值为1 805.5μg/kg,随着剖面土壤深度增加,PAHs含量总体呈递减趋势。通过来源解析,电子拆解园周围土壤中PAHs污染主要由废弃的电子电器元件的粗放燃烧和汽车尾气排放共同引起。土壤风险评估表明,7种类二噁英毒性PAHs的毒性当量(TEQPAH)在6.000×10-5~0.689pg TEQ/g,平均值为0.015pg TEQ/g;苯并(a)芘、二苯并(a,h)蒽、苯并(a)蒽、苯并(b)荧蒽、茚并(1,2,3-cd)芘致癌风险率超出百万分之一的样本比例分别为20.53%、6.62%、1.99%、2.65%、2.65%,其中采样点1、68两个点位表层土壤的苯并(b)荧蒽致癌风险率超过了万分之一。     

非道路柴油机排放颗粒物中的重金属形态及其风险评价

采集6种典型非道路柴油机排放的颗粒物样品,利用BCR连续提取法分析了颗粒物中重金属的形态。结果表明,6种典型非道路柴油机的颗粒物比排放达154~343mg/(kW·h),小功率的非道路柴油机颗粒物比排放较高;各重金属平均质量浓度排序为ZnCrAsMnPbNi≈Cu≈Cd,重金属总量约占颗粒物质量的2.22%;Ni和Cu以有机物结合态为主,其他重金属均以残渣态为主,约占总提取形态的71.83%~96.74%;所有非道路柴油机颗粒物中均存在有机物结合态重金属且比例较高,说明排放颗粒物中有机污染物和重金属结合紧密。基于风险评价法和污染系数法对重金属的生态风险进行评价,结果表明,非道路柴油机排放颗粒物中Cd的生态风险最高,Pb、Cr和Mn的风险次之。     

Combining passive samplers and biomonitors to evaluate endocrine disrupting compounds in a wastewater treatment plant by LC/MS/MS and bioassay analyses

Two types of integrative sampling approaches (passive samplers and biomonitors) were tested for their sampling characteristics of selected endocrine disrupting compounds (EDCs). Chemical analyses (LC/MS/MS) were used to determine the amounts of five EDCs (nonylphenol, bisphenol A, estrone, 17β-estradiol and 17α-ethinylestradiol) in polar organic chemical integrative samplers (POCIS) and freshwater mussels (Unio pictorum); both had been deployed in the influent and effluent of a municipal wastewater treatment plant (WWTP) in Genoa, Italy. Estrogenicity of the POCIS samples was assessed using the yeast estrogen screen (YES). Estradiol equivalent values derived from the bioassay showed a positive correlation with estradiol equivalents calculated from chemical analyses data. As expected, the amount of estrogens and EEQ values in the effluent were lower than those in the influent. Passive sampling proved to be the preferred method for assessing the presence of these compounds since employing mussels had several disadvantages both in sampling efficiency and sample analyses.     

Ecotoxicological risk assessment linked to the discharge by hospitals of bio-accumulative pharmaceuticals into aquatic media: The case of mitotane

The release of hospital wastewater into the urban sewer networks contributes to the general contamination of aquatic media by pharmaceutical residues. These residues include bio-accumulative pharmaceuticals that lead to increased risk for ecosystems because they can concentrate in organisms and food chains, and therefore reach toxic levels. In order to assess the ecotoxicological risks linked to this particular category of residues, we have developed a specific method, by combining a theoretical calculation of pollutant concentrations in organisms to estimate Body Residue (BR), and ecotoxicity biomarkers in fish cell lines, enabling the calculation of a Critical Body Residue (CBR). This method finally results in the calculation of a specific risk quotient (Qb = BR/CBR), characterizing the risk linked to this type of pollutant. This method was applied to mitotane, a bio-accumulative pharmaceutical typically found in hospital wastewater, in the framework of an exposure scenario corresponding to the discharge of all the hospital wastewaters into the Rhone River which flows through the city of Lyon, France. This approach leads to risk quotients (Qb and Qbg) much higher than those found with the classical approach, i.e. Q = PEC/PNEC (Predictive Environmental Concentration/Predictive Non Effect Concentration) = 0.0006. This difference in the appreciation of risk is important when using cytotoxicity as the criterion for measuring the toxicity of mitotane (Qb = 0.056) and it is even greater when the criterion used is genotoxicity (Qbg = 6.8). This study must be now consolidated by taking the biomagnification of the pharmaceuticals into consideration.