Household pyrethroid insecticides exposure in relation to pyrethroid metabolite and GABA level effects of young children in urban area, Bangkok Thailand

Pyrethroids are commonly used in households and affect to nervous system in children. Data on pyrethroids exposure related to neurotransmitter gamma-aminobutyric acid (GABA) is unknown. This study investigated the relationship between 3-PBA metabolites and GABA concentrations, and also determined the factors influencing pyrethroids metabolites among young children in urban areas. A repeated cross-sectional design was designed to collect the information on PYR insecticide exposure between wet (November – December 2018) and dry (April – May 2019) seasons. To collect the data, urine samples were collected from children age 2–3 years(n = 80), and the questionnaires were used with parents. The study focused on children living in full time households where PYR insect products have been applied daily. Urine samples were analyzed for the 3-PBA metabolite using gas chromatography (GC/MS) and GABA concentrations using an enzyme-linked immunosorbent assay kit (ELISA). Spearman correlations was used to determine the relationship between 3-PBA metabolite and GABA concentrations in each season, and binary logistic regression was applied to determine an association between 3-BPA metabolite and the exposure variables in each season. Mann–Whitney U test was used to evaluate difference in continuous data between wet and dry seasons. Chi-square test was applied to present difference in categorical data between wet and dry seasons. The results revealed a negative association between an increase in 3-PBA metabolite concentrations and low GABA concentrations in urine in both seasons (rs = -0.230, p-value 0.004). This study also found the increase in 3-PBA metabolite was significantly associated with the increase in cypermethrin (rs = 0.226, p-value < 0.05), and allethrin (rs = 0.274, p-value < 0.05) in dry season, but not in wet season (rs = 0.160, p-value > 0.05). Moreover, the association between exposure factors and 3-PBA metabolite concentrations were observed. seldom cleaned the floor was significantly associated with increased 3-PBA metabolite concentration in wet season (p-value = 0.038, OR = 0.089, 95%CI 0.009 – 0.870). In addition, genders and always walk bare feet inside household in a day were significantly associated with increased 3-PBA metabolite concentration in dry season (p-value = 0.041, OR = 0.333, 95%CI 0.116 – 0.956) and (p-value = 0.009, OR = 6.789, 95%CI 1.597 – 28.854), respectively. Hence, these factors could affect the levels of the neurotransmitter GABA in pyrethroids-exposed children. The study suggests that health education, raising awareness and strategies to reduce the risks from long-term PYR insecticide exposure of children living in households should be implemented.