Pesticides are chemicals widely applied in agriculture and proven environmental contaminants; their hazards include harmful effects on human health, therefore the evaluation of exposure is relevant to risk assessment. Hair is a non-invasive specimen that incorporates pollutants allowing an extended exposure window to be surveyed. Aim of this work was to develop and validate an assay for measuring 41 pesticide active principles in human hair.

Under optimised conditions, analytes were extracted by soaking hair in acetonitrile, in the presence of internal standards, under stirring and heating condition. Chemical separation was achieved using liquid chromatography with silica-based bonded phase chromatographic column. Detection and quantification were performed, with both positive and negative electrospray ionization, by a hybrid triple quadrupole/linear ion trap mass spectrometer operating in the scheduled selected reaction monitoring mode. The validated assay showed a linear dynamic range up to 10000 ng/L or 400 pg/mg hair, inter- and intra-run precisions <7%, and accuracies within 10% of theoretical concentrations. Limits of quantification were 1 ng/L or 0.04 pg/mg hair for most of the investigated pesticides. Matrix effect experiments showed that the use of internal standards allowed for the control of biases. The method was applied to the determination of pesticides in hair samples form occupationally and non-occupationally exposed individuals.

The results of this study indicate that the developed assay is useful to assess pesticides in human hair following different exposure scenarios.

农药是在农业中广泛使用的化学物质和经证实的环境污染物；它们的危害包括对人体健康的有害影响，因此接触评估与风险评估有关。头发是一种非侵入性标本，其中掺入了污染物，可以对延长的暴露时间窗进行调查。这项工作的目的是开发和验证一种测定人发中41种农药活性成分的方法。

在最佳条件下，在有内标物存在的情况下，在搅拌和加热条件下，将头发浸入乙腈中以萃取分析物。使用液相色谱法和基于二氧化硅的键合相色谱柱可实现化学分离。通过在预定的选定反应监测模式下运行的混合三重四极杆/线性离子阱质谱仪，对正电喷雾和负电喷雾电离进行检测和定量。经过验证的测定显示出线性动态范围，最高可达10000 ng / L或400 pg / mg的头发，批间和批内精密度<7％，准确度在理论浓度的10％以内。大多数研究农药的定量限为1 ng / L或0.04 pg / mg头发。基质效应实验表明，使用内标可以控制偏差。该方法用于职业和非职业接触者头发样本中农药的测定。

这项研究的结果表明，所开发的测定方法可用于评估不同暴露情况下人发中的农药。