Earlier this year we were horrified to find out that many soaps contained carcinogenic ingredients, now Dr. Shanna Swan of the University of Rochester has found that an ingredient in many plastics may cause smaller penis size and incomplete testicle descent. Noticed that your package could be shipped in a small envelope? Well it may be because of your parents’ exposure to plastics that your junk never, exactly, graduated.

The Globe and Mail reports:

Exposure of expectant mothers to phthalates, a common ingredient in many plastics, has been linked to smaller penis size and incomplete descent of testicles in their baby boys, according to a new research paper that found the chemical also appears to make the overall genital tracts of boys slightly more feminine.

The findings are sure to add more controversy to phthalates, a chemical that is added to polyvinyl chloride plastic to make it less brittle, and to many types of personal care products including fragrances, hair sprays and nail polish…

Phthalates are "probably reproductive toxins and should be eliminated from products gradually because we don't need them," said Shanna Swan, director of the Center for Reproductive Epidemiology at the University of Rochester's school of medicine, who led the team of scientists who examined the boys.

This brings a whole new meaning to “paper or plastic.” You probably don’t want to even think about bearing children yet, but very small decisions seemingly unrelated to a kid’s health may be important. So the next time you’re tempted to sip out of Solo cups amidst a game of beer pong, just think about what you’re doing to your future kids— and their sex lives!