A Review of Contamination Status and Health Risk Assessment of Volatile Methylsiloxanes in Environmental Matrices

Volatile methylsiloxanes (VMS) are a group of synthetic chemical compounds broadly used in industrial applications and consumer products, leading to a sharply increased global emission through diverse pathways. Consequently, human exposure to VMS through inhalation or other routes poses potential health risks. To provide insights for environmental contamination by VMS and its concerning health risks, a systematic literature search was conducted in online databases, including the Web of Science, PubMed, Elsevier ScienceDirect, and the China National Knowledge Infrastructure. This review analyzed contamination levels of VMS in various environmental matrices, including air, dust, water, and soil. It further summarized health risk assessments for different external exposure pathways. The exacerbation of VMS pollution is predominantly linked to the increase in atmospheric concentrations, resulting in health risks primarily driven by inhalation exposure. Vulnerable groups require greater attention as their daily intake levels may potentially approach the reference dose, including occupational populations and children residing in areas near factories. Currently, data on long-term and simultaneous environmental monitoring of VMS remain limited. Furthermore, there is a lack of established exposure guidance values, due to insufficient toxicity data and limited risk quantification methods. Therefore, advancing monitoring technologies and networks for VMS and their transformation products is crucial. Future efforts should prioritize integrating advanced tools, such as mixture toxicity models, to achieve more accurate quantification of health risks under complex exposure scenarios. Overall, this review sheds light on developing and revising regulatory frameworks for governing the production and handling of VMS, as well as guiding the health risk assessment.