The rapid decline in human fertility alone is an indication of the close links between people’s health and the quality of their environment in the broadest sense. British and Danish researchers highlight it again in a study published on Thursday, June 9 in the journal The international environment. Conducted by Andreas Kortenkamp (Brunel University of London) and Hanne Frederiksen (Rigshospitalet, University of Copenhagen), the authors present the first assessment of the risks to male fertility of mixtures of pollutants on a daily basis.
They have thus managed to rank, among the substances most suspected of harming the quality of human semen, the most decisive in the current decline. Plastics hold the top of the pavement from afar. Bisphenol A (BPA) and its substitutes (BPS, BPF) are the most important substances. They are followed by polychlorinated dioxins and other plasticizers (phthalates), some parabens, and paracetamol. According to the researchers’ estimates, the median combined exposure of the general population to these products is about twenty times the risk threshold.
At the male fertility ramp is a phenomenon identified since the thirties. A variety of factors – diet, smoking, stress, exposure to certain common chemicals, and more. – is suspected of being involved. “From now on, many studies have been done around the world to measure the characteristics of human sperm.Pierre Jouannet, Professor Emeritus at the University of Paris-Descartes, one of the great pioneers in this field of research, explained. The most serious of these show a decline in sperm quality, especially in the most economically developed countries. »
A drop from 50% to 60% in less than forty years
The numbers are striking. The most comprehensive summary published to date dates back to 2017. Conducted by the team of Shanna Swan (New York University) and published in the journal Human Reproduction Updateit indicates that the average concentration of sperm in western man has risen from 99 million to 47 million sperm per milliliter between 1973 and 2011. That is a drop of 50% to 60% in less than forty years.
Other, more recent data indicate that the problem is far from a thing of the past. In 2019, Ashley Tiegs’ team (Thomas Jefferson University, Philadelphia) was published in urologists une étude sur 120 000 American and Spanish men of couples who consulted a center d’aide à la procréation. Of this sample, the proportion of men with less than 15 million mobile sperm per milliliter increased from 12.4% to 21.3% between 2002 and 2017. This is an increase of almost 10 percentage points in fifteen years. . , within this population subgroup.
You have 64.52% of this article left to read. The suite is reserved for subscribers.