Chemicals in cosmetics and personal care products may increase cancer risk
CALIFORNIA, United States – Every time someone showers, shampoos, applies moisturizers or sunscreens, they expose themselves to dozens of controversial, possibly harmful chemicals.
Called parabens, these chemicals may be more dangerous at low doses than previously thought, according to a team of researchers from the University of California Berkeley.
The new study, published in the journal Environmental Health Perspectives, warns consumers that the chemicals can mimic the hormone oestrogen and may increase the risk of cancer.
According to the study’s lead author Dale Leitman, a gynaecologist and molecular biologist at UC Berkeley: “Although parabens are known to mimic the growth effects of oestrogens on breast cancer cells, some consider their effect too weak to cause harm. But this might not be true when parabens are combined with other agents that regulate cell growth.”
Parabens trick the body into thinking they’re actually oestrogen. The more a woman is exposed to oestrogen, whether it’s from taking oestrogen medications, experiencing menopause later in life, or being obese, the greater her risk of breast cancer. The researchers’ concern is that once inside the body, these parabens may become even more potent.
Researchers from UC Berkeley and Silent Spring, an institute that supports studies about chemicals and women’s health, wanted to know what really happens when parabens are present. To find out, they analysed breast cancer cells with two kinds of receptors called oestrogen receptors and human epidermal growth factor receptor (HER2).
About 25 per cent of breast cancers are said to have increased levels of HER2. Tumours with this receptor likely grow and expand more aggressively compared to other breast cancer types.
For the study, the researchers used naturally-developed growth factor heregulin found in breast cells to activate HER2 receptors, while the breast cancer cells are subjected to parabens.
The findings showed that parabens instigated the oestrogen receptors via activating genes that triggered the breast cells to reproduce quickly and the impact was significant.
The parabens were able to cause breast cancer cells to grow in concentrations that are 100 times lower compared to cells that were not subjected to heregulin.
These findings are said to be cause for concern because they mean paraben exposure doesn’t have to be high to lead to cancer growth.
According to the US Food and Drug Administration (FDA), moreover, parabens are one of the most commonly used preservatives in cosmetic products.
Cosmetics or body products that contain the chemicals include words that end in “paraben” in their ingredient list — methylparaben, for example. Many facial moisturizers, anti-aging creams, foundations, fragranced products, and certain types of makeup contain parabens.
The use of parabens has been under scrutiny for decades. In 1984, the Cosmetic Ingredient Review (CIR), took a closer look at the safety of different types of parabens, like methylparaben, propylparaben, and butylparaben. It decided that up to 25 percent of some products comprised parabens.
What’s more, a 2004 study detected parabens from deodorants in breast tumours, which led experts to immediately question the efficacy of previous chemical safety tests. The FDA, however, considered the results from this study too insignificant to pull parabens from the products.
“Scientists and regulators are using potency estimates from these kinds of tests and are assuming they are relevant to what goes on in real life,” said the study’s co-author Ruthann Rudel, a toxicologist at Silent Spring Institute, in a press release. “But if you don’t design the right test, you can be off by a lot.”
Going forward, the research team hopes to study how the chemicals affect humans at different points in their lives when hormones fluctuate most, like during puberty or pregnancy.
In the meantime, as researchers try to figure out the exact levels of parabens that are safe, consumers can safeguard themselves by reading the product labels. Some companies actively avoid using parabens in their ingredients.