The aim of this study was to investigate the association between serum concentrations of a group of organochlorine pesticides/
polychlorinated biphenyls with xenoestrogenic potential and the risk of
breast cancer in a female population from Tunisia. The relationship between serum levels of the
pollutants and the risk of
cancer was assessed using logistic regression analyses. In the unadjusted models, β-
hexachlorocyclohexane (β-HCH),
hexachlorobenzene,
heptachlor,
polychlorinated biphenyl congeners 138, 153, and 180, and
p,p'-dichlorodiphenyldichloroethylene (
p,p'-DDE) were positively associated with
breast cancer risk. However, when the models were further adjusted for the selected covariates, only β-HCH and
p,p'-DDE remained statistically significant, and
heptachlor was borderline significant. In addition, analyses using POP concentration tertiles corroborated a positive dose-response relationship that was significant for
p,p'-DDE (p-trend=0.020) and borderline significant for
heptachlor (p-trend=0.078). A similar trend was also confirmed for β-HCH, in which concentrations≥limit of detection were positively associated with
breast cancer risk (vs. concentrations<limit of detection, OR=3.44, p<0.05). Finally, the relative influence of each chemical in the presence of the others was assessed by entering the three chemicals in a single model with all covariates, and only β-HCH remained positively associated with the risk of
cancer (OR:1.18, 95%CI: 1.05-1.34). Our findings suggest a potential association between exposure to at least one organochlorine
pesticide and
breast cancer risk. However, our results should be interpreted with caution, and further research is warranted to confirm these findings.