According to environmentalists, certain food containers still contain dangerous perfluorocarboxylates (PFCs) despite governmental bans on the chemicals in American-made containers. However, this ban doesn’t cover containers made overseas.

Environmentalists are urging the U.S. Food and Drug Administration to place an outright ban on any containers made with toxic chemicals, regardless of their country of origin, reported The Hill. American manufacturers are not allowed to make any containers with PFCs, but companies still import internationally-made containers not manufactured under the same standards.

The environmentalist group, the Natural Resources Defense Council (NRDC), has started a petition in hopes to get the FDA to institute the outright ban.

“The FDA should swiftly ensure that these risky PFCS, which it has already asked domestic producers to stop using, aren’t sneaking into our food supply through pizza boxes or sandwich wrappers made overseas,” said NRDC senior strategic director Erik Olson.

PFCs were commonly found in pizza boxes and certain plastic sandwich wrappers. The chemicals were added to hot-food containers because they allowed them resist heat, grease, and oils.

Overly abundant amounts of PFCs in the body can lead to a number of health problems. These problems include increased risk of developing tumors, inhibited thyroid functions, reproductive problems, and slow down brain development in children.

With pizza being one of the most eaten foods in America, there’s no telling exactly how many pizzas are being eaten out of PFC ridden boxes. The same goes for sandwiches packed in the chemical-laden wrappings. Too often does the FDA get things wrong, this shouldn’t be one of them.