Much ink has recently been spilled about our environment, and potentially our bodies, being contaminated by some of the estimated 60,000 chemicals being industrially produced today. That ink itself contains the likes of perfluoroalkyl substances (PFAS) and phthalates, chemicals of concern because of their hormone disruptive properties, and in the case of PFAS, also because of their environmental persistence. That has earned the latter the nickname 鈥渇orever chemicals.鈥� Both these classes of substances are found in numerous consumer products. Phthalates are added to some plastics, including ones that are spun into fibres to make them soft and pliable, whereas PFASs have both water and oil repellant properties. It therefore comes as no surprise that these chemicals can be detected when some fabrics are subjected to chemical analysis, mostly at the parts per million level or less.
The first take-away is that what the results of such an analysis really demonstrate is the astounding capability of modern instrumentation to detect vanishingly small amounts of substances. The second point is that the presence of a chemical cannot be equated to the presence of risk! Evaluation of risk is a very complex affair and often comes down to making an educated guess given that the relevant experiment cannot be ethically, logistically or economically performed.
For example, when it comes to perfluoroalkyl substances (PFAS), the definitive experiment would involve exposing a group of subjects to varying amounts of these substances and comparing the findings to that of a control group with no exposure. The experimental and control groups would have to be followed for decades, since we are talking about chronic rather than acute effects. To add to the complexity, it should be noted that there are thousands of different PFASs that are in use and they can have totally different toxicological profiles. So which one, or which mixture would be tested? Clearly such an interventional trail cannot be carried out. We are therefore left with human epidemiological studies and laboratory experiments using animals or cells in test tubes. But people are not rats and the body is not some giant test tube, so the relevance of laboratory data to humans is hard to determine.
As far as epidemiological data go, these are clearly relevant, but generally come from large scale exposure. For example, detrimental effects of PFAS have been noted in people living around DuPont鈥檚 West Virginia Parkesburg plant where significantly high amounts of PFAS have been found in the water due to improper disposal of manufacturing chemicals. However, this may not mean much for the general population elsewhere with exposure to trace amounts. As we well know, only the dose makes the poison. The same arguments can be made for phthalates, bisphenol A, PCBs, dioxins, furans or the hundreds of other chemicals with potential toxicity that may be encountered in the environment.
All of this is to say that we cannot come to a conclusion about the risk, if any, posed by the tiny amounts of PFASs, phthalates or inorganics detected in fabrics. My guess is that absorption of any of these into the bloodstream would be inconsequential. That, though, may not be the case for cosmetics that are formulated with PFASs such as lipstick, foundations, or mascara. But the biggest concern about exposure to PFAS and phthalates is through food and water. How do these chemicals end up there? Leaching out from discarded items, for one. While wearing fabrics with PFAS may not be an issue, when large numbers of these are discarded, some PFASs end up in the water supply and from there in food. Since PFAS are also used in food packaging, migration into the contents is possible. Then there is the possibility of inadvertent release during manufacture of these chemicals.
The bottom line is that while PFAS in fabrics may pose no risk to the wearer, banning their inclusion in such items means fewer of these chemicals will be produced, and population exposure will be reduced. However, making any recommendation to the public about favouring specific clothing items based on the trivial amounts of PFAS or phthalates found, cannot be justified scientifically.
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