School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, China.
School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, China.
Chemosphere. 2023 Dec;345:140474. doi: 10.1016/j.chemosphere.2023.140474. Epub 2023 Oct 19.
The extensive use and improper handling of plastics have caused extensive microplastic (MP) pollution in terrestrial environments. Di(2-ethylhexyl) phthalate (DEHP), the main additive used in plastics, is toxic to organisms and may pose risks to human and animal reproductive functions. However, research on the release behavior of DEHP from MPs is scarce. In this study, the effects of particle size and environmental conditions (temperature, pH, ionic strength, and cation type) on DEHP release from polylactide (PLA), polystyrene (PS), and polyvinyl chloride (PVC) MPs were determined by performing leaching experiments. The results showed that when particle size decreased, the content of DEHP in the MPs and the amount of released DEHP increased though increasing specific surface area. An increase in temperature also promoted DEHP release; when the temperature increased from 15 °C to 45 °C, the amount of DEHP released from PLA, PS, and PVC increased by 38.4%, 71.0%, and 109%, respectively. The lower the crystallinity, the greater the increase in the amount of DEHP released. Ionic strength inhibited the release of DEHP from MPs. When Na concentration increased from 0 to 200 mM, the amount of DEHP released from PLA, PS, and PVC decreased by 27.4%, 41.6%, and 35.3%, respectively. The effect of Ca on DEHP release from MPs was greater than that of Na. In addition, the process of DEHP release from MPs fit well with a pseudo-first-order kinetic model. The results of this study provide a theoretical basis for managing and controlling the risks associated with plastic wastes.
塑料的广泛使用和不当处理导致了陆地环境中广泛的微塑料 (MP) 污染。邻苯二甲酸二(2-乙基己基)酯 (DEHP) 是塑料中主要的添加剂，对生物体有毒，可能对人类和动物的生殖功能造成风险。然而，关于 DEHP 从 MPs 中释放的行为的研究很少。在这项研究中，通过浸出实验，研究了粒径和环境条件（温度、pH 值、离子强度和阳离子类型）对聚乳酸 (PLA)、聚苯乙烯 (PS) 和聚氯乙烯 (PVC) MPs 中 DEHP 释放的影响。结果表明，随着粒径的减小，尽管比表面积增加，但 MPs 中 DEHP 的含量和释放的 DEHP 量增加。温度升高也促进了 DEHP 的释放；当温度从 15°C 升高到 45°C 时，PLA、PS 和 PVC 从 MPs 中释放的 DEHP 量分别增加了 38.4%、71.0%和 109%。结晶度越低，释放的 DEHP 量增加越大。离子强度抑制了 MPs 中 DEHP 的释放。当 Na 浓度从 0 增加到 200 mM 时，PLA、PS 和 PVC 从 MPs 中释放的 DEHP 量分别减少了 27.4%、41.6%和 35.3%。Ca 对 MPs 中 DEHP 释放的影响大于 Na。此外，DEHP 从 MPs 中释放的过程很好地符合伪一级动力学模型。本研究结果为管理和控制塑料废物相关风险提供了理论依据。
