Beyond phthalates: Investigating non-phthalate plasticizers in indoor environments-A nationwide survey from China

Research on plasticizers, particularly non-phthalate plasticizers (NPAEs), in indoor environments and their associated human exposure risks remains limited in China. To address this, we analyzed 374 house dust samples nationwide for 11 phthalates (PAEs) and 16 NPAEs. Nineteen of 27 target analytes were widely detected, with total plasticizer concentrations (∑₂₇plasticizers) ranging from 14.3 to 3358 μg/g (median: 226 μg/g). While PAEs dominated of total plasticizers (>70 %), however, some NPAEs, such as trioctyl trimellitate and methyl oleate, showed comparable or higher levels than certain PAEs, indicating their increasing presence. A temporal analysis of PAE occurrence in indoor dust from 2007 to 2023 revealed a significant downward trend. Geographically, Northeast China exhibited the highest ∑₂₇plasticizers levels (median: 539 μg/g), 1.93-3.73 times higher than those in other regions. Additionally, urban households displayed significantly higher ∑₂₇plasticizers concentrations than rural homes, suggesting more intensive emission sources. Floor and dwelling materials were identified as key contributors to plasticizer contamination. Although estimated hazard quotient values suggest minimal health risks under current exposure conditions, the complexity of exposure pathways warrants further investigation. This study provides a national-scale assessment of indoor plasticizer contamination and human exposure risks, offering critical insights for environmental health research and regulatory policies.