Aix Marseille Univ, CNRS, LCE, Marseille, France.
Sci Rep. 2016 Sep 15;6:33456. doi: 10.1038/srep33456.
The persistent organic pollutants (POPs) due to their physicochemical properties can be widely spread all over the globe; as such they represent a serious threat to both humans and wildlife. According to Stockholm convention out of 24 officially recognized POPs, 16 are pesticides. The atmospheric life times of pesticides, up to now were estimated based on their gas-phase reactivity. It has been only speculated that sorption to aerosol particles may increase significantly the half-lives of pesticides in the atmosphere. The results presented here challenge the current view of the half-lives of pesticides in the lower boundary layer of the atmosphere and their impact on air quality and human health. We demonstrate that semivolatile pesticides which are mostly adsorbed on atmospheric aerosol particles are very persistent with respect to the highly reactive hydroxyl radicals (OH) that is the self-cleaning agent of the atmosphere. The half-lives in particulate phase of difenoconazole, tetraconazole, fipronil, oxadiazon, deltamethrin, cyprodinil, permethrin, and pendimethalin are in order of several days and even higher than one month, implying that these pesticides can be transported over long distances, reaching the remote regions all over the world; hence these pesticides shall be further evaluated prior to be confirmed as POPs.
持久性有机污染物 (POPs) 由于其物理化学性质，可以广泛分布在全球各地；因此，它们对人类和野生动物都构成了严重威胁。根据《斯德哥尔摩公约》，在 24 种正式认定的 POPs 中，有 16 种是农药。迄今为止，农药的大气半衰期一直是根据其气相反应性来估算的。人们只是推测，气溶胶颗粒的吸附可能会显著增加农药在大气中的半衰期。这里呈现的结果对目前关于大气底层边界层中农药半衰期及其对空气质量和人类健康影响的观点提出了挑战。我们证明，大多数吸附在大气气溶胶颗粒上的半挥发性农药对于大气的自清洁剂——高反应性羟基自由基 (OH) 来说具有非常长的半衰期。烯唑醇、四唑醇、氟虫腈、恶草酮、溴氰菊酯、噻菌灵、氯菊酯和二甲戊灵在颗粒相中的半衰期为几天甚至一个月以上，这意味着这些农药可以长距离运输，到达世界各地的偏远地区；因此，在被确认为持久性有机污染物之前，这些农药需要进一步评估。
