It’s not only that sperm counts have plummeted by 50 percent in the last forty years; it’s also that this alarming rate of decline could mean the human race will be unable to reproduce itself if the trend continues…. In animals there have been changes in mating behavior, with more reports of male turtles humping other male turtles, and female fish and frogs becoming masculinized after being exposed to certain chemicals.

How and why could this be happening? The answer is complicated. Though these interspecies anomalies may appear to be distinct and isolated incidents, the fact is that they all share several underlying causes. In particular, the ubiquity of insidiously harmful chemicals in the modern world is threatening the reproductive development and functionality of both humans and other species. The worst offenders: chemicals that interfere with our body’s natural hormones. These endocrine-disrupting chemicals (EDCs) are playing havoc with the building blocks of sexual and reproductive development. They’re everywhere in our modern world—and they’re inside our bodies, which is problematic on many levels.

Excerpt from Count Down: How Our Modern World Is Threatening Sperm Counts, Altering Male and Female Reproductive Development, and Imperiling the Future of the Human Race by Shanna H. Swan, PhD with Stacey Colino, Simon & Schuster, New York, USA, 2020 (Chapter One: Reproductive Shock, pp. 7 & 9).

Shanna H. Swan, PhD, is an award-winning scientist based at Mt. Sinai Medical Center, New York, and one of the world’s leading environmental and reproductive epidemiologists.

Stacey Colino is an award-winning writer specializing in health and environmental issues. Her work has appeared in such magazines as Newsweek, Time, Parade, National Geographic, and Good Housekeeping.