Breast cancer link to heavy metal found in cosmetics

Although cadmium is never used as any kind of ingredient in cosmetics or personal care formulations, it can sometimes appear as a byproduct in a range of different finished goods, including color make-up products such as mascara, eyeliner, blusher and foundation.

Although cadmium is invariably only found in trace amounts in cosmetics and so not deemed to be toxic, the study underlines the fact that only ‘small concentrations’ of cadmium made breast cancer cells increasingly aggressive the longer they were exposed.

Trace amounts of cadmium in a range of sources​

The study, which was led by associate professor of biochemistry Maggie Louie, also underlines that cadmium is also found in trace amounts in a range of other sources, including food, water and air particles, pointing to the risk of accumulated exposure to the heavy metal.

"Many of us are exposed to very low levels of cadmium from the environment on a daily basis, and our research shows that even small concentrations of this metal at prolonged exposures can cause breast cancer cell growth."​

Louie’s study findings were presented at the annual meeting for the American Society for Biochemistry and Molecular Biology, yesterday, which was held in San Diego in conjunction with the Experimental Biology 2012 conference.

The research team was focused on the fact that breast cancer cells result from abnormal growth of cells in the mammary gland, driven by increased levels of estrogen.

Cadmium as endocrine disruptors​

Heavy metals such as cadmium can act as endocrine disruptors, in turn mimicking estrogen and disrupting the hormone dependent pathways, the research underlines.

In her presentation and the published study results, Louie stresses the fact that previous research has underlined the relation to cadmium as an endocrine disruptor due to acute exposure of the heavy metal. However, this study is one of the few to demonstrate disruption from exposure to chronic levels of cadmium.

"The relationship between cancer and chronic exposures at low levels is important to understand because most people are not exposed to high levels of heavy metals, unless they work in manufacturing plants that deal with such metals,"​ Louie said.

"Unfortunately, cadmium is all around us – it is in our food, our water, our make-up and our air. Understanding the role that cadmium plays in the progression of breast cancer is extremely important in order to find better ways to prevent the disease from advancing.”​

Further research on how heavy metals contribute to breast cancer​

Although the report details how cadmium can enter the body through contaminated foods and tobacco smoke, it does not reveal how it can enter body cells when it is contained in products that are applied to the skin, such as a make-up or other cosmetics. However, given that make-up products are so commonly used, it remains important to include such products in the study.

“Ninety percent of cancer deaths are associated with the cancer spreading to other parts of the body. If we can prevent the tumor from spreading, we have a better chance of treating cancer​."

Further research is now expected to concentrate on how proteins such as SDF-1 are attributed to the aggressive characteristics of the cadmium exposed mammary cells, in turn understanding their role in cadmium-induced carcinogenesis and throwing light on how heavy metals are a contributing factor in breast cancer.