A new study has found a possible link between organic solvent exposure and male breast cancer (MBC)[i]. Despite the rarity of breast cancer in men, any connection with solvent use is of interest, because occupational exposures too many chemicals are present in many jobs mostly held by men. In a previous study, the same research group found that motor vehicle mechanics and painters with probable exposure to organic solvents had a two- to three-fold increased risk of MBC[ii], and the aim of the current study was to advance the hypothesis of a link between solvents and MBC.
The researchers compared 104 cases of MBC with 1901 controls. The participants provided detailed information on their work history, medical history and lifestyle. A job-exposure matrix was used to estimate their exposure to some types of solvents. Exposure to higher cumulative levels of trichloroethylene was associated with an approximately doubled risk of MBC, and the risk increased with increasing level of exposure. There was a possible increased risk with exposure to benzene, but some risks were not statistically significant, and there was no exposure-response trend (the increased risk from lower exposures was greater than the increased risk from higher exposures).
Although this is the largest case-control study of MBC and exposure to solvents, a limitation of the study is that there were only small numbers of cases exposed to some solvents. This means that the analyses have low statistical power for detecting associations. The researchers conclude that more epidemiological studies of populations with well-characterised exposures are required.
[i] Laouali, N. et al. Occupational exposure to organic solvents and risk of male breast cancer: a European multicenter case-control study. Scandinavian Journal of Work, Environment & Health doi:10.5271/sjweh.3717 http://www.sjweh.fi/show_abstract.php?abstract_id=3717 (Accessed 23 February 2018)
[ii] Villeneuve, S. et al. Occupation and occupational exposure to endocrine disrupting chemicals in male breast cancer: a case-control study in Europe. Occup Environ Med 67, 837–844 (2010). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3151527/ (Accessed 26 February 2018)