The rate of male infertility has increased by 700 percent over the last 15 years. Researchers also found that the quality of semen has dramatically declined over this period.
In a study to be presented at the conference of the American Society for Reproductive Medicine in Denver, Colorado, on Monday, Ashley Tiegs, from the Reproductive Medicine Associates of New Jersey, and colleagues analyzed semen samples from major fertility centers in the United States and Spain between the years 2002 and 2017.
They found that the number of men seeking treatment in these facilities increased from just 8,000 at the start of the period to 60,000.
The researchers also found plummeting quality of semen. An increasing number of men have a sperm count so low, an IVF would be necessary for conception. The number of men with normal sperm count also dropped.
The researchers said that the drop in semen quality is likely caused by environmental factors, which include smoking, obesity, stress, and exposure to chemicals.
"Environmental factors like plastics and smoking and obesity are big ones," Tiegs told the Daily Mail. "'We know obesity is on the rise and it does affect sperm quality. It increases the risk of morbidity and mortality, but it can also affect offspring too."
What particular chemicals affect male infertility? According to Mirror, these include those used to make plastic flexible and furniture flame-retardants, chemicals that can enter the food chain through plants and animals.
In an article published by GQ, Daniel Noah Halpern wrote about endocrine disruptors, chemicals that can affect the hormones. Many of the compounds used to make plastic harder and stronger such as Bisphenol A, or BPA, and those that make plastic soft and flexible like phthalates are consummate endocrine disruptors.
BPA is present in food containers, water bottles, and sales receipts.
Phthalates and BPA mimic estrogen in the bloodstream. Thus, men with a lot of phthalates in their system produce less testosterone and less sperm.
Phthalates can be found in the coating of pills and nutritional supplements. They are also present in detergents, modeling clay, textiles, and food packaging, which means they can also be found in a range of packaged food such as sauces, soups, yogurt, and milk.
According to Halpern, the U.S. Centers for Disease Control and Prevention has determined that just every single person in the United States has measurable levels of phthalates in his or her body.
Avoiding these chemicals is virtually impossible.