Drinking water,diet, indoor air: Comparison of the contribution to environmental micropollutants exposure

This study collated 254,441 analytical results from drinking water quality monitoring in order to compare levels of exposure of the French adult population from drinking water with that from total diet for 37 pesticides, 11 mineral elements, 11 polycyclic aromatic hydrocarbons (PAH), 6 non dioxin-like polychlorobiphenyls (NDL PCB), 5 ether polybromodiphenyl ethers (BDE), 2 perfluorinated compounds. It also compares levels of exposure from drinking water with that from inhalation of indoor air for 9 volatile organic compounds (VOC) and 3 phthalates. The vast majority of the water analysis results showed values below the limits of quantification and this comparison was primarily made on the basis of a highly pessimistic scenario consisting in considering the data below the limits of quantification as being equal to the limits of quantification. With this conservative scenario, it can be seen that tap water makes a minor but potentially non-negligible contribution for a few micropollutants, by comparison with diet and air. It also shows that exposure through drinking water remains below the toxicity reference values for these substances. Apart from a few extreme values reflecting exceptional local situations, the concentrations measured for the minority of positive samples (below the 95th percentile value) suggest a very low risk for human health. Lower limits of quantification would however be of use in better estimating the safety margin with regard to the toxicity reference values, in particular for BDE, PAH and NDL PCB.     

绵阳市部分食品中二氧化硫残留量监测结果

目的了解绵阳市部分食品中二氧化硫残留情况。方法从绵阳城区及所辖的江油市、北川县、梓潼县、三台县、盐亭县的大型超市、农贸市场等不同地点采集食品样品,按照GB/T 5009.34-2003方法进行检测。结果共抽检食品样品132份,103份合格,合格率为78.03%;29份不合格,不合格率为21.97%。119份样品中检出二氧化硫,检出率为90.15%。结论绵阳市部分市售食品中二氧化硫检出率高,合格率偏低,相关部门应采取相应措施,加强宣传教育,加大监管与监测力度,以保护消费者的身体健康。     

Dissipation Kinetics of Flubendiamide on Chili and Soil

Average initial deposits of flubendiamide on chili were found to be 1.06 and 2.00 mg kg⁻¹, respectively, following two applications of flubendiamide 480SC at 60 and 120 g a.i. ha⁻¹ at 10 days interval. More than 80% of flubendiamide residues dissipated just after 3 days of the last application at both the dosages. Residues of flubendiamide dissipated below detectable level of 0.01 mg kg⁻¹ in 7 and 10 days at single and double dosages, respectively. Half-life (t _1/2) of flubendiamide on chili was observed to be 0.96 and 0.91 days, respectively, at single and double dosages. Desiodo flubendiamide was not detected at 0.01 mg kg⁻¹ level in chili samples collected at different time intervals. Red chili and soil samples collected after 20 days did not reveal the presence of flubendiamide or its metabolite desiodo flubendiamide.     

固相萃取-毛细管气相色谱法测定莪术中15种有机氯农药的残留量

目的用固相萃取-毛细管气相色谱分析方法测定莪术中15种有机氯农药残留量。方法样品以混合溶剂超声提取、Florisil固相萃取小柱净化处理后,采用DB-1701毛细管气相色谱柱分离样品,电子捕获检测器检测。内标法定量,计算有机氯农药的残留量。结果15种农药在5~500μg.L-1范围内具有良好的线性关系,相关系数均大于0.995。15种农药3个不同浓度的平均回收率为83.1%~110.6%,RSD%为3.4%~14.8%。最小检测量为0.08~1.5μg.L-1。被测样品中均含有不同程度的有机氯农药。结论本法简便、灵敏、准确、重现性好,可用于中药材中有机氯类农药的残留量测定。     

HPLC residues of enrofloxacin and ciprofloxacin in eggs of laying hens

Eggs of 12 laying hens with 5 mg/kg/day oral administration of 5% enrofloxacin (EFX) or ciprofloxacin (CFX) solution during 5 days contained residues from 0.02 to 1.98 μg/g (EFX) or 0.14 to 0.28 μg/g (CFX). At identical dosage regime High Performance Liquid Chromatograhy (HPLC) residues of EFX were 6-fold greater than CFX ones. Maximun concentrations were detected at the second day after the administration withdrawal. The limits of detection were 0.019 μg/g for EFX and 0.156 μg/g for CFX. The recovery was 36–50% for CFX and 49–85% for EFX. The withdrawal treatment periods in hens are six days for EFX and five days for CFX in order to avoid violative levels of egg residues.     

Detection of Photochemically Induced Cuticle-Bound Residues of Parathion by Immunoassay

An indirect competitive ELISA was developed using a polyclonal rabbit antiserum against diethyl thionophosphates. It was found to show its highest sensitivity for the organophosphorus insecticide parathion. This assay was applied to detect bound residues of parathion formed by photodegradation in fruit cuticles. Detection of bound residues was successful in the dot-blot immunoassay as well as in the ELISA test format. In accordance to earlier model studies on the photochemistry of parathion, the same results were achieved using cuticles treated with the photoproduct nitrosoparathion.     

柑橘和土壤中四螨嗪残留量的液相色谱测定法

目的 建立用液相色谱测定柑橘和土壤中四螨嗪的农药残留量的方法.方法 样品用丙酮提取,干装硅胶柱净化,利用HP 1100高效液相色谱进行检测.结果 四螨嗪农药的检出限为0.01 mg/kg,土壤的添加回收浓度在0.05 ～2.01mg/kg时,平均回收率为92.1％ ～95.9％,相对标准偏差为0.30％～ 5.34％,柑橘的添加回收浓度在0.05 ～2.01 mg/kg时,平均回收率为92％ ～ 95.4％,相对标准偏差为0.33％ ～4.60％.结论 该方法的灵敏度、准确度和精密度均符合农药残留测定的技术要求.     

气相色谱法测定水果中灭多威残留量

本文用气相色谱法测定水果中灭多威残留量,采用带硫滤光片的光焰光度检测器检测,灭多威的检测限为0.2ng,在水果中的最低捡出浓度为0.05mg/kg,加标浓应为0.10——5.0mg/kg时,平均回收率为89.3％——104.7％,高、中、低三种浓度的变异系数均小于5％。     

Validation of an HPLC-UV method for the determination of ceftriaxone sodium residues on stainless steel surface of pharmaceutical manufacturing equipments

In pharmaceutical industry, an important step consists in the removal of possible drug residues from the involved equipments and areas. The cleaning procedures must be validated and methods to determine trace amounts of drugs have, therefore, to be considered with special attention. An HPLC-UV method for the determination of ceftriaxone sodium residues on stainless steel surface was developed and validated in order to control a cleaning procedure. Cotton swabs, moistened with extraction solution (50% water and 50% mobile phase), were used to remove any residues of drugs from stainless steel surfaces, and give recoveries of 91.12, 93.8 and 98.7% for three concentration levels. The precision of the results, reported as the relative standard deviation (RSD), were below 1.5%. The method was validated over a concentration range of 1.15-6.92 μg ml(-1). Low quantities of drug residues were determined by HPLC-UV using a Hypersil ODS 5 μm (250×4.6 mm) at 50 °C with an acetonitrile:water:pH 7:pH 5 (39-55-5.5-0.5) mobile phase at flow rate of 1.5 ml min(-1), an injection volume of 20 μl and were detected at 254 nm. A simple, selective and sensitive HPLC-UV assay for the determination of ceftriaxone sodium residues on stainless steel surfaces was developed, validated and applied.     

Persistence of Ethion Residues on Cucumber, Cucumis sativus (Linn.) using Gas Chromatography with Nitrogen Phosphorus Detector

Residues of ethion were estimated in cucumber by gas liquid chromatography following three applications of the insecticide at 375 and 750 g a.i ha⁻¹. The average initial deposits of ethion on cucumber fruits were found to be 2.40 and 4.97 mg kg⁻¹ at single and double dosages, respectively. Residues of ethion dissipated below the maximum residue limit (MRL) of 0.5 mg kg⁻¹ in 7 days. Half-life (T_1/2) for degradation of ethion on cucumber was observed to be 2.92 days at recommended dosage. A waiting period of 7 days is suggested for safe consumption of cucumber.