Crossing dangerous barriers: PFAS are absorbed internally via the skin
25 Oct 2022 --- Per- and polyfluoroalkyl substances (PFAS) in cosmetics can penetrate the human skin barrier and accumulate within the body, increasing the risk of cancer. This is according to research from the German Federal Institute for Risk Assessment within the Department of Food Safety that assessed the impact of 13C4-Perfluorooctanoic acid (13C4-PFOA) mixed into a commercial sunscreen.
A crucial takeaway from the study is that in the case of appropriate levels of PFOA in the cosmetic product, transdermal absorption of the substance (and most likely other PFAS) is not insignificant and can contribute to the overall exposure to PFAS.
“Germany is working with the Netherlands, Denmark, Norway and Sweden on a proposal for a European Union-wide ban on PFAS. This is planned to be submitted to ECHA by January 2023,” Jessica Ebelt, Department of Risk Communication at the German Federal Institute for Risk Assessment, tells PersonalCareInsights.
“PFOA is prohibited in cosmetic products – entry 1561 of Annex II of the EU Cosmetic Regulation – with the restriction entering into force in 2019.”
“In addition, cosmetic ingredients are subject to other regulations such as the EU Regulation on persistent organic pollutants, which stipulates limit values for PFOA, its salts and PFOA-related compounds occurring as an unintentional trace contaminant in substances, mixtures and articles,” she adds.
The researchers note that dermal exposure to PFAS from cosmetic products has previously been negligible. This is why the researchers looked at how cosmetic products can contribute to PFAS exposure through transdermal absorption via the study.
According to the findings of epidemiological studies and associations between internal exposure to perfluoroalkyl acids (PFAA) and the use of specific cosmetic products, it is plausible that the transdermal route is relevant and can significantly contribute to internal exposure to PFAS.
PFAS and their role in cosmetics
PFAS are a complex class of man-made chemicals with high mobility and stability that can accumulate in humans and the environment, especially long-chain PFAA. Although dietary intake is the primary exposure route, transdermal uptake from cosmetic items is typically considered minimal.
Transdermal absorption of PFOA from cosmetic products can contribute to overall PFAS exposure if appropriate levels are present in the cosmetic product.The researchers note that these findings, together with subsequent research using cosmetics from the European market, show that PFCA of different chain lengths can be found in cosmetics as impurities or degradation products of precursor compounds that are added as active ingredients.
Furthermore, based on the European Commission’s database on cosmetic ingredients, PFCA substances are used intentionally in cosmetic products as emulsifiers, stabilizers, surfactants or solvents.
Last week in related news, the Governor of California signed Assembly Bill 2771, a law that bans intentionally added toxic PFAS chemicals, also known as “forever chemicals,” from cosmetics sold in California, US. The bill intends to protect personal care and beauty consumers from the risk of chemical build-up that can lead to health issues including cancer reported Breast Cancer Prevention Partners (BCPP).
Consumer exposure to impurities
The studies on PFAS in cosmetics reveal a very complex issue overall; the relevance for consumer exposure is anticipated to depend on various factors.
These factors include the range of PFAS and their PFCA contaminants or impurities used for production in a specific country at a particular time, usage frequency and the amount of skin area affected by a specific product.
The study findings show high uptake of some long-chain PFAA via transdermal absorption in humans for PFOA blended into a sunscreen. In the past, certain cosmetic products had active chemicals that were PFAS pollutants or impurities.
Based on the European Commission’s database on cosmetic ingredients, PFCA substances are used intentionally in cosmetic products as emulsifiers or stabilizers.This route of exposure may have contributed to the internal exposure to PFAA, as already demonstrated by epidemiological observations, depending on these levels and the use (frequency and skin area affected).
Limitations and future studies
Using sunscreen as a cosmetic product and PFOA as a model compound, this experimental inquiry has the characteristics of a proof-of-principle test in one individual, the researchers say.
They add that it clearly shows that significant levels of PFOA permeate the skin under these circumstances. A larger sample size would shed light on the individual variability of the absorption process. Still, it would limit the results to one compound (PFOA) in one cosmetic product (sunscreen).
Therefore, researching humans using specific PFAS in certain cosmetic products is not a reasonable way to address the complicated issue of PFAS as an ingredient in cosmetic products.
Despite the study findings, the researchers add that one unanswered question remains regarding the role the various PFAS, such as FTOH or PAP, play as active ingredients in cosmetic products.
In related news, the European Commission (EC) was noted to capitulate to industry demands that it postpone long-awaited plans to enforce a ban on hazardous chemicals such as PFAS, bisphenol and PVC, according to a draft working document leaked from the EC.
By Nicole Kerr
