Safe or unsafe: Role of exposure time and interactions between volatile organic compounds in mixtures

• Published in: Building and environment Vol. 271; p. 112619
• Main Authors: Li, Xiaoying, Li, Zhenhai
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.03.2025
• Subjects: Adult drosophila; Long-term exposure; Mixture; Survival analysis; Synergy; Long-term exposure; Survival analysis; Adult drosophila; Synergy; Mixture
• DOI: 10.1016/j.buildenv.2025.112619
• ISSN: 0360-1323

•Formaldehyde could induce hormesis on female D. melanogaster lifespan.•Long-term exposure risks potentially exhibited the accumulation and age specificity.•Low-concentration Benzene-Formaldehyde mixtures exhibited the greatest synergy.•Interaction may alter into addition with low-benzene ratio or high mix concentration. Humans are generally exposed to various mixtures with long-term and low-concentration scenarios, yet such scenarios still are not adequately discussed. Given the ethical and cost considerations, it is impractical to conduct exposure experiments with human subjects in such scenarios. Hence, based on Drosophila melanogaster (D. melanogaster) mortality, benzene, toluene, and formaldehyde, commonly detected in the air, were selected for evaluating the risk associated with the long-term and low-concentration exposures to individual and combined chemicals. This study employed survival analyses to investigate the potential cumulative and age-specific effects of exposures. Furthermore, an index was proposed to evaluate exposure risk, and the concentration-effect relationships for benzene and formaldehyde exposures were established, which revealed a stimulatory effect of formaldehyde exposure on female D. melanogaster lifespan. Although several toluene treatments significantly increased the survival probability of D. melanogaster compared to the control, a concentration-dependent manner was not observed. The benzene and formaldehyde mixtures, the lower the component concentrations, the greater the synergistic interactions. The exposure risks of the FA0.075+B0.15 and FA0.15+B0.075 treatments were about six times as high as that predicted by the additivity concept. This suggested that low-concentration mixtures potentially caused unexpected exposure risks. This study aims to improve the data deficiency of long-term, low-concentration, and mixture exposure scenarios in exposure experiments, which can support the risk evaluation of personnel's environmental exposure in the future. [Display omitted]