Long-term occupational and environmental exposure to penconazole and tebuconazole by hair biomonitoring

Penconazole (PEN) and tebuconazole (TEB) are fungicides widely used in vineyards. The aim of this the study was to assess the suitability of hair to assess long-term exposure to PEN and TEB. Hair samples of agricultural workers exposed to PEN (AW-PEN, 18 subjects) or TEB (AW-TEB, 2 subjects) during the application of fungicides, agricultural workers relatives (AR, 4 subjects), and research staff technicians (RS, 5 subjects) were collected before (PRE-EXP) and after (POST-EXP) the application season. PEN in PRE-EXP samples was quantifiable in all AW and AR (medians from 1.4 to 7.9 pg/mg hair) and in one RS (1.4 pg/mg hair); PEN in POST-EXP samples was always quantifiable (medians from 2.6 to 23.7 pg/mg hair), with higher levels in AW. Comparing PRE- vs. POST-EXP samples, an increase in PEN level in AW and RS was found. TEB in PRE-EXP samples was quantifiable in most AW and AR (median from 2.1 to 15.5 pg/mg hair), but not in RS; TEB in POST-EXP samples was similarly quantifiable in AW and AR, and was quantifiable also in RS (from 1.4 to median of 141.3 pg/mg hair). Comparing PRE- vs. POST-EXP samples, an increase in TEB level in AW and RS was found. In AW, a positive correlation between the number of PEN treatments during the season and the POST-EXP level of PEN in hair was found (N = 8, Spearman rho = 0.794, p = 0.019). Our results suggest that PEN and TEB accumulate in hair during the agricultural season and that hair is a promising matrix for biomonitoring long-term exposure.