Aluminum salts used in antiperspirants have been linked to elevated risk of breast cancer.
A study published in the September issue of Journal of inorganic biochemistry demonstrated that aluminum may affect the breast cancer risk by interfering with estrogen functions.
Clinical studies, according to Darbre P.D. from The University of Reading, showed breast cancer more often develops in the upper outer quadrant of the breast where genomic instability has already been reported, meaning that the locally applied cosmetic chemical may have a role in the increased risk of breast cancer.
Aluminum is known to be gentoxic, capable of mutating DNA and having epigenetic effects. Because of this, aluminum may be potentially involved in the carcinogenesis in the breast.
The role of estrogen in the breast cancer is well established and depends upon intracellular receptors, which function as ligand-activated zinc finger transcription factors, according to Darbre, meaning that there is a point in space where aluminum may influence.
Darbre reported that aluminum chloride or aluminum chlorohydrate can indeed interfere with estrogen receptors in human breast cancer cells in a way that it affects ligand binding and "estrogen-regulated reporter gene expression".
But Darbre said more study is needed to identify the molecular basis of this action.