Currently there is incredible concern over what the group of toxic chemicals called PFAS (per- and polyfluoroalkyl substances) are doing to humans. PFAS are commonly known as "forever chemicals" because of their persistence in our bodies and environment. They are all around us (e.g., in personal care products, cosmetics, food packaging, nonstick cookware, textiles, carpets), and as a consequence almost all of us have them in our bodies.
Why be concerned over PFAS chemicals? They are endocrine (hormone) disruptors and have numerous harmful health effects, including all sorts of reproductive effects (e.g., decreases in sperm numbers, increased rates of infertility), decreases in testosterone, increased risk of cancer, and immune effects. Studies also find that they cross the placenta and accumulate in the fetus.
Now another worrisome large study (864 young men, 18.9 to 21.2 years old) has been published. Danish researchers found that those men who had been exposed to higher levels of PFAS during pregnancy had lower levels of sperm (both sperm concentration and sperm count), and a higher proportion of not swimming correctly and nonmoving sperm in the adult sons. This means that prenatal exposure has an effect on both quantity and quality of sperm in adulthood.
The PFAS levels were first measured during pregnancy (in the mother's plasma) during the first trimester, when the male reproductive system is developing. Sperm counts have been dropping rapidly in the past 40 years throughout the developed world, and these chemicals may be one of the reasons.
Bottom line: We can't totally avoid these chemicals, but the good news is that we can lower by a lot how much we are exposed to. And your levels can go down within weeks.
PFAS are commonly used because they have water, dirt, stain, and oil repellent properties. For example, they are used in water-resistant and long-lasting cosmetics, and in rugs and upholstery with added stain-resistance. This means that there are many simple ways to lower your exposure, mainly by some lifestyle changes (e.g., by using regular stainless steel pots and not non-stick pots).
A good list of ways to lower your exposure to PFAS and other harmful chemicals, especially if you are pregnant or thinking of pregnancy, or have children. Can also go to ewg.org for lists of personal care products that are PFAS and toxin free.
Nice, short article from The Guardian: Study links in utero ‘forever chemical’ exposure to low sperm count and mobility
A new peer-reviewed Danish study finds that a mother’s exposure to toxic PFAS “forever chemicals” during early pregnancy can lead to lower sperm count and quality later in her child’s life.
PFAS – per- and polyfluoroalkyl substances – are known to disrupt hormones and fetal development, and future “reproductive capacity” is largely defined as testicles develop in utero during the first trimester of a pregnancy, said study co-author Sandra Søgaard Tøttenborg of the Copenhagen University hospital.
The study builds on others that found similar issues, but it is the first to look for exposure to more than two PFAS compounds and to assess exposure during early pregnancy, which is the male reproductive organ’s “primary developmental period”.
Researchers checked the mothers’ blood for 15 PFAS compounds, and found seven in large enough concentrations to include in the study.
Those mothers with higher levels of exposure more frequently raised adult men with lower sperm counts, as well as elevated immotile sperm levels, meaning their sperm did not swim. This exposure also increased the amount of non-progressive sperm – sperm that do not swim straight or swim in circles. Both issues can lead to infertility.
The ubiquitous chemicals are estimated to be in 98% of Americans’ blood, and they can cross the placental barrier and accumulate in the growing fetus. A recent analysis of 40 studies of umbilical cord blood from around the world found that PFAS were detected in all 30,000 samples collectively examined.