You have no doubt heard about “forever chemicals,” per- and polyfluoroalkyl compounds. Scientists shorten this chemical terminology to the acronym PFAS. Manufacturers use PFAS in nonstick pots and pans, food packaging, stain-resistant carpets and fabrics, as well as water-repellent shoes and outerwear. Such forever chemicals are found in air, soil and drinking water. We call them forever chemicals because they do not break down easily. As a consequence, they will persist in our environment—and in us—for decades. These compounds may cause deleterious changes in liver function, increased cholesterol levels, elevations in blood pressure and reduced fertility. Should we include thyroid cancer in this list?
Do PFAS Increase the Likelihood of Thyroid Cancer?
A new study suggests that forever chemicals may also increase the risk for thyroid cancer (eBioMedicine, Oct. 24, 2023). Currently, approximately 45,000 American adults develop this cancer each year. While doctors can treat it successfully if it is diagnosed promptly, the incidence of this malignancy has been rising worldwide. Researchers suspect that exposure to PFAS chemicals may be partly to blame.
In the new investigation, scientists analyzed blood samples from 88 patients with and 88 individuals without thyroid cancer. They completed chemical analyses of eight different specific PFAS compounds.
Those with higher levels of PFAS in their bodies “showed a 56% increased risk of thyroid cancer diagnosis” as the levels of PFOS (perfluorooctanesulfonic acid) doubled. Since use of these compounds is worldwide and rapidly increasing, the risk of exposure is global. As a result, the authors call for large-scale prospective studies to better understand the health consequences of forever chemicals.
PFAS Concerns in China:
A new study from China underscores the complexity of this question (Chemosphere, Oct. 2023). This research, like the study you just read about, is a case-control study in which investigators compare people with thyroid cancer to those without. The Chinese scientists analyzed blood samples for 12 different PFAS chemicals, and the findings were not straightforward. Higher levels of PFOS were, in fact, associated with thyroid malignancy. However, PFDA and a few other compounds were actually associated with lower risk. These scientists too call for large-scale prospective studies to clarify the relationship between PFAS and health.
Learn More:
Some of our podcasts have more information on this topic. Regarding PFAS, you may wish to listen to Show 1212: Should You Worry About Forever Chemicals? Show 1301: What Are Forever Chemicals Doing in Food Packaging? offers an update. Dr. Antonio Bianco and patient advocate Mary Shomon discuss a range of thyroid problems including cancer in Show 1096: What You Need to Know About Treating Thyroid Disease.
