Exposure to organophosphorus pesticides in Norwegian mothers and their children: Diurnal variability in concentrations of their biomarkers and associations with food consumption.

Several studies have suggested that exposure to organophosphorus (OP) pesticides is detrimental for health, and in particular for children where moderate doses may have a negative impact on the neurodevelopment. This study surveys levels of the 6 non-specific urinary metabolites (dialkyl phosphates (DAPs)) of OP pesticides in Norwegian mothers (n=48) and their children (n=54), and examines the diurnal variation in concentrations as well as associations with consumption of specific food products. The highest median concentration measured in urine was found for dimethyl thiophosphate (5.3 and 5.5ng/mLSG ; specific gravity corrected) for both children and mothers, respectively, followed by diethyl phosphate (3.8 and 5.3ng/mLSG , respectively). The intra-class correlation coefficients of DAPs among mothers were moderate (0.49-0.68), and consumption of fruit explained between 8% and 55% of the variations in the mothers' and their children's urinary DAP concentrations.