A paper just published in Tox Sci shows that PFOS (the chemical that used to be the prime ingredient in Scotchgard) suppresses the immune system at levels, that didn’t cause noticeable toxicity that are same as what are found in the general population. Great. So, basically, many people in the US who show no other signs may have compromised immune systems because of PFOS. And what’s worse is that other compounds like PFOA, related to Teflon treatments (read more here), also have the same effects in other mouse studies.
You know this is really a toxicologist’s nightmare. I’d like to think that because of this really well-done and important study, something will happen on the PFC front. Really though, I’m not too hopeful. For decades people sit on data that PFCs are harmful and don’t follow up on it. Gee, good thing we did the studies. Also, our environmental laws are so weak, companies can simply not submit them to the gov’t and eat the fine (if it ever comes). Then when some of the problems of PFCs (don’t break down, found in everyone, immune and development problems) become public, 3M got out of the business but DuPont ramped up production to fill the void. They continue to fight doing anything serious about it and despite this new study and volumes of research showing the harms and the sources, they will continue to make these chemicals and commit chemical trespass.
Sometimes, it’s just not worth it to get up in the morning as a toxicologist. Studies that find harm are dismissed for one reason or another by industry and the gov’t is too weak to do anything about it. So what really is the point of conducting a study if a positive finding is going to be ignored?
PS And don’t anyone comment that it’s mice not people; it would be almost impossible to do an epi-study in the US population on this problem ($ and logistics). 1) we’re all exposed so there is no real control so you’d have to look at a dose response. 2) Everyone is exposed to a mixture of PFC chemicals as well as other chemicals that may be immunosupressants; confounding the study. The combination of those two would make the study, well, near impossible.