Plastic (cont.)

Medical Editor:

What is polyvinyl chloride (PVC, vinyl)?

Polyvinyl chloride (PVC or vinyl) can be manufactured to be either rigid or flexible and is identified with the number 3. When flexible, PVC is used for medical bags, shower curtains, shrink wrap, and deli and meat wrap. The rigid PVC comprises 70% of all manufactured PVC. This is used to make construction materials such as pipe, siding, window frames, railing, fencing, and decking. PVC has been said to have had a major impact on improving life around the world.

However, there are claims that PVC poses serious environmental health threats. According to the Center for Health, Environment, and Justice, the production of PVC requires chemicals like the "highly polluting chlorine," the "cancer-causing" vinyl chloride monomer (VCM), and ethylene dichloride (EDC). They also claim that PVC plastic requires large amounts of toxic additives to make it stable and usable. These additives are released during use and disposal, resulting in "elevated human exposures to phthalates, lead, cadmium, tin, and other toxic chemicals." In 2000, the Environmental Protection Agency (EPA) proposed national standards to limit air toxic emissions from polyvinyl chloride production plants.

The FDA acknowledges that the building block of PVC, vinyl chloride, is a human carcinogen. They conclude that the amount contained in the PVC food packaging is within safe limits. In 2002, the FDA recommended that a specific compound used as a plasticizer in PVC either be labeled or removed from the medical bags in which it was being used. This compound, DEHP, had shown some toxic and carcinogenic effects in lab animals, but the effects on humans were unknown. The invasive medical procedures in which this was being used may have exposed people to DEHP levels that would exceed the amount determined to be safe in humans.

What is low-density polyethylene (LDPE)?

Low-density polyethylene (LDPE) is used for its toughness, flexibility, and relative transparency. LDPE is used to make bottles that require extra flexibility. To take advantage of its strength and toughness, it is used to produce grocery bags and garbage bags, squeezable bottles, shrink wrap, stretch films, and coating for milk cartons. It can also be found in toys, container lids, and packaging. It is identified as number 4.

Medically Reviewed by a Doctor on 6/3/2015