“Over the course of 50 years, sperm concentration has fallen about 50% around the world,” said senior study author Melissa Perry, dean of the College of Public Health at George Mason University in Fairfax, Virginia.

“What is not known is the culprit,” Perry said. “While there are likely many more contributing causes, our study demonstrates a strong association between two common insecticides —organophosphates and N-methyl carbamates — and the decline of sperm concentration.”…

“They are widely used in agriculture on the crops we eat,” Perry said. “We use them in structural applications within homes and buildings, apartment buildings, as well as for ornamental lawn upkeep. They’re available for consumer purchase so organophosphate exposures have been demonstrated to be relatively widespread.”