Balloons and condoms that come in contact with body fluids discharge chemicals suspected of being human carcinogens, a study suggests. The chemicals, called nitrosamines, are frequent by-products of the vulcanizing process used to strengthen rubber and make it highly elastic.
The chemicals cause cancer in lab animals. Governments in Europe and North America recommend that manufacturers of baby-bottle nipples and other products for infants restrict nitrosamine concentrations. Germany also applies a similar, voluntary guideline to balloons.
Scientists at the Chemical and Veterinary Investigation Institute Stuttgart in Fellbach, Germany, immersed unrolled condoms for 1 hour in a solution made to chemically resemble human sweat. Using a different solution made to simulate saliva, they similarly exposed material cut from balloons. Afterward, they tested the solutions for nitrosamines that had leached from the rubber products.
The researchers found that up to 380 micrograms of nitrosamines were released from each kilogram of balloon rubber exposed to a solution. For the condoms, concentrations were as high as 660 µg/kg.
The researchers also tested balloons for substances that sometimes become nitrosamines in the body. They found concentrations of these chemicals, called nitrosatable compounds, up to 4,300 µg/kg.
In a separate experiment, the scientists compared leaching in 10 minutes of contact between condom rubber and artificial sweat with the effect of an hour-long exposure. They found that most of the escaped chemicals leached out soon after contact began.
Kathi Ellendt and her colleagues report their findings in the March Molecular Nutrition & Food Research. The team suggests that governments might more aggressively regulate the chemical contents of balloons and condoms.