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Dose-response relationships in human experimental exposure to solvents
Ivo Iavicoli1, Giovanni Carelli, Alessandro Marinaccio
1Institute of Occupational Medicine, Catholic University of the Sacred Heart, Largo Francesco Vito 1, Rome, Italy. iavicoli.ivo@rm.unicatt.it
Summary
Human studies on chemical exposure did not find biphasic dose-response relationships. Methodological limitations in existing research prevent definitive conclusions on these toxicological effects.
Area of Science:
- Toxicology
- Pharmacokinetics
- Occupational Health
Background:
- Biphasic dose-response relationships have been observed in animal models for various chemicals.
- Human experimental data on these relationships, particularly via inhalation, are less understood.
- Previous toxicological studies often exclude human subjects, limiting direct applicability.
Purpose of the Study:
- To investigate the existence of biphasic dose-response relationships in humans experimentally exposed to common chemical substances.
- To review and analyze human exposure data from the last three decades.
- To identify potential biphasic effects in human toxicology.
Main Methods:
- Systematic literature review of human experimental exposure studies over the past 30 years.
- Focus on inhalation as the primary route of exposure.
- Analysis of data for chemicals including hydrocarbons, esters, alcohols, ketones, ethers, glycoethers, halogenated hydrocarbons, and carbon disulfide.
Main Results:
- No biphasic dose-response relationships were detected in the reviewed human experimental exposure studies.
- Significant methodological limitations were identified across the studies, hindering detailed data examination.
- The available human data were insufficient to support the presence of biphasic effects.
Conclusions:
- Current experimental data do not support biphasic dose-response relationships for human exposure to the studied chemical classes via inhalation.
- Further research with improved methodologies is needed to fully elucidate dose-response dynamics in humans.
- The findings highlight critical gaps in human toxicological research regarding dose-response complexities.
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