Influence of microplastics occurrence on the adsorption of 17β-estradiol in soil.

High levels of steroid estrogens are continuously detected in the soil environment, and even the concentration in vegetables and fruits has reached levels that have an impact on children's health, which has attracted growing attention. Moreover, microplastics (MPs) in the soil system are also of increasing concern worldwide. The effects of MPs on the adsorption of organic pollutants in soil systems, however, remain largely unexplored. In this study, MPs common in greenhouse vegetable soil (polyethylene, polyvinyl chloride and polystyrene) were selected to investigate the effect of MPs occurrence on the adsorption of 17β‑estradiol (E2) in soil under various conditions. The experimental results showed that the adsorption capacity of MPs to E2 is stronger than that of soil. Moreover, the occurrence of MPs in soil increased the adsorption capacity for E2, and the addition amount and aging of MPs enhanced the promotion effect. This enhancement indicated that the input of MPs into soil might reduce the mobility of E2 by improving the adsorption capacity of the soil. These results deepen the understanding of the adsorption behavior of E2 in the coexisting system of MPs and soil and provide a theoretical basis for E2 pollution control.