Abstract
Breast cancer is the most frequent cancer in women. It is believed that among the causes of breast cancer, hereditary factors account for only 5-10% of risk and the environmental exposures to environmental contaminants account for an additional 30-50% of risk. This paper summarizes findings related to the risk of breast cancer due to exposure to following environmental contaminants: polycyclic aromatic hydrocarbons, polychlorinated biphenyls and dioxins, organochlorine pesticides, organophosphorous pesticides, bisphenol A, phthalates, parabens, organic solvents, atmospheric pollutants, alkylphenols, metals, ionizing radiation, electromagnetic field and light pollution. Results obtained in in vitro experiments with breast cancer cell lines and in vivo with model rodents as well as in population based case-control studies are presented and the mode of action of individual environmental contaminants on mammary gland is discussed. Attention is also devoted to the effects of the timing of exposure to environmental contaminants (mainly exposition during development of the mammary gland) on breast cancer risk. Outcomes of professional exposure to some environmental contaminants on breast cancer risk are analysed as well