Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 511443, China.
Research Center of Low Carbon Economy for Guangzhou Region, Key Laboratory of Philosophy and Social Science in Guangdong Province of Community of Life for Man and Nature, Jinan University, Guangzhou 510632, China.
Environ Sci Technol. 2022 Jun 21;56(12):8053-8060. doi: 10.1021/acs.est.2c01094. Epub 2022 May 30.
Liquid crystal monomers (LCMs) have been found to accumulate in indoor environments, but the emission kinetics of LCMs from electronic devices are not well understood. Leakage from damaged liquid crystal displays may be an important mechanism for LCMs to enter the environment and become potential health hazards to humans. To address this issue, we conducted chamber experiments to characterize the emissions of LCMs from obsolete smartphone screens and estimated the doses of residential and occupational exposures to LCMs. The emission rates of the detected LCMs were in the ranges of 0.1-7 μg m h at 80 °C, 0.05-7 μg m h at 60 °C, and 0.002-0.2 μg m h at 25 °C. Liquid crystal monomers with large molecular weights and low volatilities tended to accumulate at screen surfaces and were re-emitted at elevated temperatures, leading to high emission rates of heavy LCMs upon thermal treatment. The estimated doses of residential and occupational exposures to individual LCMs were 0.0001-0.009 and 0.007-2 ng kg d, respectively. As LCMs are potentially carcinogenic based on in silico assessments, LCMs emitted from obsolete smartphones in indoor settings may become human health hazards.
液晶单体（LCMs）已被发现会在室内环境中积累，但电子设备中 LCMs 的排放动力学尚未得到很好的理解。从损坏的液晶显示器中泄漏可能是 LCMs 进入环境并成为人类潜在健康危害的重要机制。为了解决这个问题，我们进行了腔室实验，以表征废弃智能手机屏幕中 LCMs 的排放，并估计了住宅和职业暴露于 LCMs 的剂量。在 80°C 下，检测到的 LCMs 的排放率在 0.1-7μg m h 之间，在 60°C 下为 0.05-7μg m h，在 25°C 下为 0.002-0.2μg m h。具有较大分子量和低挥发性的液晶单体倾向于在屏幕表面积聚，并在高温下重新释放，导致热处理时重 LCMs 的排放率很高。估计的住宅和职业暴露于个别 LCMs 的剂量分别为 0.0001-0.009 和 0.007-2ng kg d。由于基于计算机的评估表明 LCMs 具有潜在的致癌性，因此室内环境中废弃智能手机中排放的 LCMs 可能会对人类健康构成危害。
