Association between Haematological Parameters and Exposure to a Mixture of Organophosphate and Neonicotinoid Insecticides among Male Farmworkers in Northern Thailand

Associations between neonicotinoids metabolites and hematologic parameters among US adults in NHANES 2015-2016

Hematologic parameters are important indicators for monitoring the physiological changes and human health. Neonicotinoids (NEOs) exhibit toxic effects and can affect hematologic parameters. However, the effects of exposure to NEOs metabolites on hematologic parameters in the general population remain unknown. We examined the relationship between NEOs metabolites and hematologic parameters using a cross-sectional study design in 1397 adults of the National Health and Nutrition Examination Survey (NHANES) 2015-2016. The levels of NEOs metabolites in urine and hematologic makers were measured. Multivariate linear regression models were performed to examine the relationship between exposure to NEOs metabolites and hematologic parameters. Detectable urine levels of clothianidin (CLO) was inversely associated with hematocrit (β =  - 0.689; 95% CI: - 1.335, - 0.042). Detectability of 5-hydroxy-imidacloprid (HIMI) was inversely correlated with basophil percentage (β =  - 0.093; 95% CI: - 0.180, - 0.007). N-Desmethyl-acetamiprid (NDE) was related to reduced white blood cells (WBC) (β =  - 0.419; 95% CI: - 0.764, - 0.074) and neutrophil counts (β =  - 0.349; 95% CI: - 0.623, - 0.074). Imidacloprid-equivalent total neonicotinoids (IMIeq) was negatively related to red blood cells (RBC) (β =  - 0.058; 95% CI: - 0.097, - 0.020), hemoglobin (β =  - 0.149; 95% CI: - 0.282, - 0.015), and hematocrit (β =  - 0.484; 95% CI: - 0.855, - 0.113). We also observed that exposure to NEOs metabolites was sex specifically related to hematologic alterations. For example, IMIeq was associated with reduced basophil counts (β =  - 0.016; 95% CI: - 0.028, - 0.003), basophil percentage (β =  - 0.092; 95% CI: - 0.169, - 0.016), RBC (β =  - 0.097; 95% CI: - 0.156, - 0.038), hemoglobin (β =  - 0.200; 95% CI: - 0.355, - 0.045), and hematocrit (β =  - 0.605; 95% CI: - 1.111, - 0.098) only in males. These results provide the first evidence that exposure to NEOs metabolites can disturb hematologic homeostasis in the general population, and the effects may be sex specific.

Neonicotinoid Insecticides and Their Metabolites Can Pass through the Human Placenta Unimpeded

Studies on neonicotinoid (NEO) exposure in pregnant women and fetuses are scarce, and transplacental transfer of these insecticides is unknown. In this study, parent NEOs (p-NEOs) and their metabolites (m-NEOs) were determined in 95 paired maternal (MS) and cord serum (CS) samples collected in southern China. Imidacloprid was the predominant p-NEO in both CS and MS samples, found at median concentrations of 1.84 and 0.79 ng/mL, respectively, whereas N-desmethyl-acetamiprid was the most abundant m-NEO in CS (median: 0.083 ng/mL) and MS (0.13 ng/mL). The median transplacental transfer efficiencies (TTEs) of p-NEOs and m-NEOs were high, ranging from 0.81 (thiamethoxam, THM) to 1.61 (olefin-imidacloprid, of-IMI), indicating efficient placental transfer of these insecticides. Moreover, transplacental transport of NEOs appears to be passive and structure-dependent: cyanoamidine NEOs such as acetamiprid and thiacloprid had higher TTE values than the nitroguanidine NEOs, namely, clothianidin and THM. Multilinear regression analysis revealed that the concentrations of several NEOs in MS were associated significantly with hematological parameters related to hepatotoxicity and renal toxicity. To our knowledge, this is the first analysis of the occurrence and distribution of NEOs in paired maternal-fetal serum samples.