Biological Monitoring and Health Effects in beta -Hexachlorocyclohexane (HCH) Exposed Workers

Background: Hexachlorocyclohexane (HCH) isomers have been largely employed as pesticides during the 1960's-1970's, and included into the Stockholm Convention persistent organic pollutant list in 2009 with the aim to reach their global elimination. beta-HCH isomer is characterized by a strong lipophilicity, bio-persistence and potential harmful properties for human health. Dispersion of industrial processes and uncontrolled waste storage caused a global environmental beta-HCH contamination. This still represents a public and occupational health concern, not only for past-exposed subjects, but also for the populations that may still be exposed to highly polluted environmental matrices and food. Objective: To provide a critical overview of the existing evidence exploring beta-HCH biomonitoring data and possible health effects in workers involved in the production and use of such compound. Methods: A systematic search and revision of available literature was performed in Pubmed, Scopus, and ISI Web of Science databases. Results: Conclusive evidence concerning the possible dose-response relationship in beta-HCH occupational settings cannot be extrapolated due to the heterogeneity in explored contexts, and the lack of information on environmental conditions and levels of exposure. Nevertheless, biomonitoring data support the need for a deeper understanding of the toxico-kinetic and dynamic profile of the substance, once absorbed into the organism, and possible early alterations in endocrine signaling. Conclusion: The potential toxicity, bioaccumulation and bio-magnification properties of beta-HCH make necessary to plan preventive actions aimed to manage the beta-HCH risk, through the reduction of exposure levels and the definition of health surveillance programs, including biological monitoring investigations, for the general and occupational exposed populations.