Abstract：
Socio-economic activities like food trade can increase the uncertainty of human risk of persistent organic pollutants (POPs). We compared the change in model predicted α-hexachlorocyclohexane (α-HCH) cancer risk (CR) with and without grain trade in mainland China. In scenario without grain logistics, α-HCH moved fast away from southern and southeastern China via northward atmospheric transport. However, the grain logistics from northeastern China delivers the α-HCH previously accumulated in northeastern sink back to densely populated areas in recent years, which enhance CR by >50 % in the southern seaboard of China. The northward movement of grain production center and recent grain deficiency in southern provinces induced by dietary pattern changes is identified as the major driving factors of the reversed transport of α-HCH. The finding highlights the potential of socio-economic activities that can otherwise offset the risk reduction effect of the geochemical cycle of POPs.
摘要：
食品贸易等社会经济活动会增加人类持久性有机污染物（POPs）风险的不确定性。我们比较了中国大陆有和没有谷物贸易的模型预测的α-六氯环己烷（α-HCH）癌症风险（CR）的变化。在没有粮食物流的情况下，α-六氯环己烷通过向北的大气输送从中国南部和东南部快速移动。然而,中国东北的粮食物流近年来将以前在东北下沉的α-HCH送回人口稠密地区，这使得中国南部沿海地区的CR提高了50%以上。粮食生产中心的北移和膳食模式变化引起的南方省份近期粮食短缺被确定为甲型六氯环己烷逆向运输的主要驱动因素。这一发现突出了社会经济活动的潜力，否则这些活动可以抵消持久性有机污染物地球化学循环的风险降低效应。
