New methodology for extracting pesticides from hair samples for subsequent chromatographic analysis

The use of pesticides poses significant risks to both the environment and public health, particularly impacting farmers who are directly exposed during their daily activities. Therefore, it is crucial to develop methodologies that accurately assess this exposure to safely quantify the levels of pesticides to which the population is subjected. In this context, hair has proven to be an effective biological matrix, as it offers long-term stability of pesticide residues and allows for quick sample collection. This study aims to develop a rapid and safe extraction method for pesticide analysis in hair samples. The sample preparation process has been streamlined into three steps: washing, chopping, and simultaneous grinding/extraction. Validation results confirmed the reliability and robustness of the extraction method for 51 multiclass pesticide compounds, with quantification limits ranging from 0.61 to 20.67 pg mg^-1. Analysis of variance demonstrated that the method is both selective and linear, with a coefficient of determination exceeding 0.99. Recovery rates were satisfactory, ranging from 87.8% to 110.7%, and good repeatability was observed (RSD < 20%). The analysis of 121 real samples validated the functionality of the method, as at least one pesticide was detected in 100% of the samples analyzed. Azoxystrobin was the most frequently detected pesticide, appearing in 92.56% of the samples at concentrations of up to 3075.22 ± 1.44 pg mg^-1, followed by carbendazim (65.29%) and tebuconazole (43.80%). Thus, the developed method proves to be effective for the extraction and quantification of various pesticide classes, making it a valuable tool for assessing both direct and indirect exposure among farmers and the general population.