National Institute for Nutrition and Health, Chinese Center for Disease Control and Prevention, Beijing, 100050, China.
College of Life and Environmental Sciences, Minzu University of China, Beijing, 100081, China.
Environ Geochem Health. 2021 Oct;43(10):3871-3881. doi: 10.1007/s10653-021-00873-7. Epub 2021 Mar 12.
Methyl siloxanes are widely found in the environment, but little is known about the distributions of these chemicals in soils especially in areas where they are manufactured. We determined the concentrations of four cyclic (D-D) and 13 linear methyl siloxanes (L-L) in the soils from a siloxane-manufacturing site in China; the total concentrations of these 17 siloxanes (TSi) in the soils were 17.1-3,191 (median, 134) ng/g. We did not find extremely high concentrations of siloxanes in the soils. The median concentrations of total cyclic siloxanes (TCSi) were approximately sevenfold higher than those of total linear congeners. Hexamethylcyclotrisiloxane and octamethylcyclotetrasiloxane contributed a median of 59.7% and 20.3% of the TSi concentrations, respectively. Higher concentrations of soil TCSi were found in the silicone-manufacturing area relative to the other study areas. Source analysis indicated that industrial activities contributed substantially to soil siloxanes, in addition to the contribution of the siloxane emissions from specific consumer products. We calculated that the median values of daily TSi intakes through soil ingestion were 0.021 and 0.138 ng/kg-body weight/day for adults and children, respectively, under high exposure scenarios. Although our estimated daily intakes of the chemicals from soils were low, more research is required to improve our understanding of the health risks posed to humans exposed to siloxanes through other pathways.
甲基硅氧烷广泛存在于环境中，但人们对这些化学物质在土壤中的分布知之甚少，特别是在其生产的地区。我们测定了中国一家硅氧烷生产厂土壤中四种环状（D-D）和 13 种线状甲基硅氧烷（L-L）的浓度；这些 17 种硅氧烷（TSi）在土壤中的总浓度为 17.1-3191（中位数，134）ng/g。我们没有在土壤中发现极高浓度的硅氧烷。总环状硅氧烷（TCSi）的中位数浓度约为总线状同系物的 7 倍。六甲基环三硅氧烷和八甲基环四硅氧烷分别占 TSi 浓度的中位数 59.7%和 20.3%。与其他研究区域相比，在硅氧烷生产区发现土壤 TCSi 浓度更高。来源分析表明，除了特定消费品的硅氧烷排放对土壤硅氧烷的贡献外，工业活动也对土壤硅氧烷有很大贡献。我们计算出，在高暴露情景下，成人和儿童通过土壤摄入的 TSi 的每日中位数摄入量分别为 0.021 和 0.138ng/kg-体重/天。尽管我们从土壤中估算出的这些化学物质的每日摄入量较低，但仍需要进一步研究，以提高我们对通过其他途径接触硅氧烷的人类所面临的健康风险的认识。
