Certain “forever chemicals” may increase the risk of one of the fastest-growing cancers in America, a study suggests.
Doctors at Mount Sinai Hospital in New York tested blood samples from people with and without thyroid cancer and found that patients with the disease were 56 percent more likely to have levels of PFAS chemicals in their systems.
PFAS are called “forever chemicals” because they are virtually impossible for the body to break down and have been used since the 1940s to make thousands of everyday products — from nonstick cookware to raincoats.
Thyroid cancer has become increasingly common since then, a peak of 240 percent between 1973 and 2002. But the main explanation for this is the improved diagnostic skills, which allow doctors to detect diseases early.
The chemical studied here is called n-PFOS and is most commonly used as a stain repellent in clothing and carpeting, and as a grease-resistant coating for food packaging.
Researchers found that every time PFAS levels in blood samples doubled, the risk of being diagnosed with thyroid cancer increased by 56 percent
PFAS is a common contaminant in many household items, from cookware to hamburger wrappers. It can remain in the environment and in human tissue for years, even decades, before being cleared
The Mount Sinai study adds valuable evidence supporting suspected links between PFAS exposure and thyroid cancer.
Dr. Lauren Petrick, professor of public health at the Icahn School of Medicine at Mount Sinai and co-author of the study, said: ‘To our knowledge, this is the first human study to look at links between PFAS exposure and the risk of thyroid cancer. diagnosis.’
PFAS chemicals disrupt the function of the endocrine system, of which the thyroid gland is a part. The researchers noted that PFAS in water is a significant source of exposure, but did not indicate how each person’s blood levels could become so high.
When PFAS enter the body through food and water that people eat and drink or by breathing polluted air, they can spread throughout the body into tissues and organs.
Some PFAS compounds can bind to thyroid hormone receptors to mimic or block the body’s natural hormones, throwing the system out of balance. PFAS can also disrupt the release of thyroid hormones, which are crucial for regulating the body’s metabolism.
When the system for managing and producing hormones is disrupted, the result can be unhindered cell growth and replication, a hallmark of cancer growth.
PFAS also cause inflammation in the body, leading to DNA damage in thyroid cells. This can result in genetic mutations that stimulate the production of cancer cells.
The latest finding builds on previous research into links between thyroid problems and PFAS, particularly the effects on pregnant women and their unborn babies.
The latest study uses blood samples from 88 adults with thyroid cancer and 88 healthy people collected between 2008 and 2021 as part of the medical school’s extensive collection of patient health information and blood and serum samples.
All of the subjects, with an average age of 46, were from the New York metropolitan area, which researchers considered a major advantage because it gave them “a diverse ethnic population.”
Thyroid cancer affects the gland in the front part of the neck that produces hormones to regulate the body’s metabolism, heart rate, blood pressure and temperature.
This is part of the body’s endocrine system, which PFAS chemicals have been shown to disrupt due to their ability to mimic thyroid hormones and prevent the production or transport of hormones.
It is estimated that 44,000 Americans will be diagnosed with thyroid cancer this year and approximately 2,100 will die. The survival rate for most types of thyroid cancer is high if detected early: about 98 percent.
Once the cancer has spread to other parts of the body, that survival rate drops to about 70 percent.
More than 80 percent of people with thyroid cancer had papillary thyroid cancer, the most common variant with the best survival rate. Five percent had follicular thyroid cancer, which is still survivable but tends to be more aggressive.
And 10 percent had a type of thyroid cancer of unknown origin, although some may have had the most advanced and aggressive variant: anaplastic thyroid cancer.
They tested the blood plasma samples for eight different types of PFAS chemicals. When levels of n-PFOS in blood plasma doubled from exposure, the risk of a thyroid cancer diagnosis increased by 56 percent.
Dr. Petrick said, “The results of this study provide further confirmation for the PFAS health crisis and underscore the need to reduce and hopefully one day eliminate PFAS exposure.”
Although the researchers found the strongest link between cancer and a specific subtype of PFOS chemicals known as n-PFOS, they also found links between cancer and other types of forever chemicals.
Their research was published in the journal eBioMedicine.
PFAS chemicals have been used since the early 20th century in the production of waterproof raincoats and nonstick cookware.
They also help make firefighting foam, food packaging and covering carpeting to repel stains. They have even been used in children’s toys.
Their constant presence in everyday life causes the chemicals to leak into the environment, such as when you scrub a frying pan in the sink.
PFAS have been found in drinking water supplies across the US due to contaminated runoff from chemical-producing factories and the widespread use of pesticides.
Certain parts of the country, such as Brunswick County, North Carolina and nearby Fayetteville, have seen disturbing clusters of cancers in their communities that are believed to be linked to a nearby factory formerly run by PFAS manufacturer DuPont.
And there is evidence that bad actors, including DuPont and 3M, knew about the harmful effects of exposure to the chemicals they produced as early as the 1960s.
Concerns have been raised repeatedly for decades. In the 1970s, the DuPont-funded Haskell Laboratory found that PFAS was “highly toxic by inhalation and moderately toxic by ingestion.”
Tests in dogs in the same decade showed that animals ingesting a single dose of PFAS died up to two days later.
In 1980, DuPont also discovered that two of eight employees who had been pregnant while working in their factories gave birth to babies with deformities.
But the company did not publicize the findings, saying the following year: “We know of no evidence of birth defects caused by (PFAS) at DuPont.”
They also assured employees that PFAS was no more toxic than “table salt.”
But instead of removing the chemicals from their production processes, the companies relied on that information, allowing risky products into people’s homes.
This cover-up has been compared to the actions of major tobacco companies to downplay the risks of smoking for decades in order to protect their profits.
DuPont claims it does not make or produce PFOS or another perennial chemical called PFOA the broader use of PFAS ‘is limited’.
However, DuPont had produced a chemical called C8 since at least the 1980s. C8 is the same chemical compound as PFOA.
3M, for its part, said last year that it would stop using forever chemicals.
But the damage has already been done. Specifically, it takes PFOS almost five years to reduce its concentration in the bloodstream by half, and PFOA about three and a half years.
They can take hundreds of years to break down naturally.
PFOS and PFOA do not break down in the environment and can easily move through soil and contaminate drinking water.
The chemicals are so well entrenched in the environment that an estimated 97 percent of Americans have PFAS chemicals circulating in their blood.
Dr. Petrick said, “Today it is nearly impossible to avoid PFAS in our daily activities. We hope these findings raise awareness of the seriousness of these perennial chemicals.
‘Everyone should discuss their exposure to PFAS with their treating physician to determine their risk and get screened if necessary. Additionally, we need continued industry changes to eliminate PFAS altogether.”