Abstract
As a newly emerging persistent environmental contaminant, perchlorate (ClO4-) has adverse effects on thyroid function by inhibiting iodide uptake and could result in neurodevelopment deficits. Our study was performed to investigate the concentration of perchlorate in size-segregated airborne particulate matter (APM) and evaluate its human exposure for children and adults. In this study, 45 size-segregated APM samples were collected from Changsha, China, during July 20 to July 31, 2016. The total APM concentrations ranged from 93.367 to 253.271 mu g/m(3) (mean 154.651 +/- 59.175 mu g/m(3)), and a bimodal size distribution was observed during the sampling period. The concentrations of perchlorate in size-segregated APM were in the range of 0.05-4.99 ng/m(3) (mean 2.03 ng/ m(3)). Exposure evaluation indicated that the ingestion was the predominant exposure pathway for daily intake of perchlorate via size-segregated APM, and children are more likely to intakemore perchlorate via APM than adults. We suggested that the risk of exposure to perchlorate for children is worthy of attention, and a further study is required, especially for seasonal variations.