Simultaneous determination of multi-class pesticide metabolites in fish (Siluriformes: Ariidae): protocol developed for human dietary risk in Ceara coast, Brazil

An analytical protocol for the determination of multi-class pesticide metabolites chlorpyrifos-methyl (Chlorp-M), S-metolachlor (S-Metola), malaoxon (malaox), 2-chloro-4,6-diamino-1,3,5-triazine (2-CAAT), carbofuran phenol (CarbPhenol), 3-phenoxybenzoic acid (3-PBA) and one polycyclic aromatic hydrocarbon metabolite 1-hydroxypyrene (1-OHP) in fish was developed using the analytical technique GC-MS. Besides the verification of metabolite occurrence in catfish from both metropolitan region and intensive farming region, the protocol was applied to evaluate human health risk due to the contaminated fish consumption in Brazilian tropical semiarid coast, for the first time. Following the national and international quality standards, the analytical protocol showed acceptable recoveries with good repeatability. Limit of detection (L-D) and limit of quantification (L-Q) values ranged from 0.15 mu g L-1 to 36.0 mu g L-1 and from 0.55 mu g L-1 to 112.9 mu g L-1, respectively, and the sensitivity was considered satisfactory since it is a complex matrix. Only tree pesticide metabolites were detected in the captured catfish. CarbPhenol and 3-PBA presence may be attributed to the application in rural and urban activities for pest control, public health campaigns and household, while malaox presence may be due to the dengue control program. Malaox contents were significantly higher than 3-PBA and CarbPhenol for the three estuaries of the Ceara coast, but the dietary risk due to the consumption of these fish, mainly for the coastal communities, based on the values established for their parental compounds, was considered low for both 3-PBA and malaox, and of probable high risk for CarbPhenol. Results represent an alert to the high possibility of risks to human health due to the overuse of pesticides in Brazil, mainly carbofuran pesticide.