Reheated food is an inevitable part of college life, but most college students are not aware of the risks they take every time they place plastic Tupperware into the microwave.

Environmental estrogens like Bisphenol-A (BPA) are found in most food packaging. Even in small amounts, environmental estrogens can affect human health. In extreme cases, they may help initiate cancer. Most breast cancers depend on estrogen to trigger tumors to grow large enough and metastasize into other vital organs.

Chiefly found in bicarbonate plastics (plastics marked as ‘7-PC’, or generally thicker plastics), BPA is not commonly found in canned goods or soda cans. However, the predominant source of BPA is the coating used to prevent metallic tastes in products that go through a high heating process.

Suzanne Snedeker ’78, associate director of translational research at Cornell’s Program on Breast Cancer and Environmental Risk Factors, said to keep in mind the heat rule. “Plastic and heat don’t work together — a variety of chemicals can leach out of plastic. Microwaving and heating plastic in any form should be avoided,” she said.

According to Snedeker, safety precautions take just a little bit more work — from removing food from plastic containers into glass and ceramic ones before heating in the microwave and avoiding the use of plastic wrap by using deep dishes. Other tips include avoiding Teflon products, using tin water bottles, eating fresh and organic foods or using products clearly marked “BPA-free.”

It should be noted that the effects of estrogens are hardly limited to women. “Environmental estrogens are not good for men, women or the environment,” Snedeker said. While they do not affect men as much in regards to cancer, studies have shown that BPA affects sexual development in men by altering the maturation and function of their sperm.

BPA and other environmental estrogens are currently being reevaluated by the FDA. Previous studies have been discredited by most researchers due to conflicts of interest and gaps in reporting. Companies that make products that contain BPA assert that its negative effects only surface because of consumer abuse and inappropriate use, but studies by other federal agencies suggest that the low-to-medium amounts of BPA found in everyday products are a substantial health concern.