Profiles of neonicotinoid insecticides and characteristic metabolites in paired urine and blood samples: Partitioning between urine and blood and implications for human exposure

• Published in: The Science of the total environment 2021-06, Vol.773, p.145582, Article 145582
• Main Authors: Xu, Miaomiao, Zhang, Zhanpeng, Li, Zhiyong, Kan, Shunyan, Liu, Zhaoxiang, Wang, Desheng, Liu, Qihui, Zhang, Hua
• Format: Article
• Language: English
• Subjects: Alkenes; Blood; China; Female; Humans; Insecticides - analysis; Male; Metabolites; Neonicotinoid insecticides; Neonicotinoids; Partitioning; Urine; Young Adult
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2021.145582

Neonicotinoid insecticides (NEOs) are widely used for pest control worldwide. However, only a few studies have analyzed NEOs and their metabolites in blood samples, and no study has measured the concentrations of NEOs and their metabolites in paired urine and blood samples. In this study, six NEOs and three characteristic metabolites were detected in 196 paired urine and blood samples collected from young adults from China. The NEOs and their metabolites were widely detected in paired urine (67%–91%) and blood (64%–97%) samples, and the median levels ranged within 0.01–1.15 ng/mL in urine and 0.08–0.80 ng/mL in blood. Olefin-imidacloprid (Of-IMI) and 1-methyl-3-(tetrahydro-3-furylmethyl) urea (UF) were the most abundant target compounds in the urine (32.4%) and blood (26.4%) samples, respectively. Gender-related differences were observed in the concentrations of most NEOs and their metabolites in the urine and blood samples. The partitioning of target analytes between blood and urine (NEOs-B/NEOs-U ratios) was also calculated in this study. The B/U ratios of most NEOs and their metabolites were below 1, and positive correlations were observed between urine and blood in most levels of NEOs and their metabolites. This finding indicates that urinary levels are good predictors of human exposure to NEOs and their metabolites. The estimated daily intake (EDI) and the imidacloprid-equivalent (IMIeq) levels of NEOs and their metabolites in 196 young adults were also determined. The median EDI values (ng/kg bw/day) of ΣNEOs (sum of NEOs and their metabolites) and IMIeq in females (194.9 and 458.2) were slightly higher than (p > 0.05) those in males (157.1 and 439.7). This finding shows young adults are extensively exposed to NEOs and their metabolites. To our knowledge, this study is the first to report about NEOs and their metabolites in paired samples of urine and blood in China. [Display omitted] •First study to analyze levels of NEOs and their metabolites in paired urine and blood samples.•Of-IMI and UF are the dominating NEOs and metabolites in urine and blood, respectively.•The blood/urine ratios of most NEOs and their metabolites are lower than 1.•Young adults are widely exposed to NEOs and their metabolites.