Photos: Plastic by the numbers

Polyvinyl chloride, or No. 3 PVC, is found in shower curtains, meat and cheese wrappers, three-ring binders, some bottles, plumbing pipes, and building materials. Commonly called vinyl, PVC and closely-related PVDC differ from other vinyls, which lack the toxic chloride. PVC continues to be used in many toys.

The plastics industry defends the safety of PVC, but it's the most toxic plastic, according to many environmental and health groups. Both the making and disposal of PVC release dioxin, one of the most poisonous, cancer-linked chemicals, into the air and water.

PVC alternatives include PEVA for shower curtains and PVA in paints and glues. However, unless otherwise marked, most vinyl products use PVC.

The first Saran Wrap was made of PVDC, but the brand switched to less-toxic LDPE (No. 4) several years ago. Neither Glad nor Ziploc use PVDC, although some deli counters and cheese sellers continue to wrap their goods in it. Consumer Reports found 10 years ago that DEHA leached from PVDC wrap into cheese.

For flexibility, PVC children's toys and sex toys also contains phthalates, which are now commonly found in the blood of humans. These chemicals are known to interrupt hormonal activities and are tied to infertility and early-onset puberty. Electronics makers including Apple have been criticized for using phthalates in gadgets including iPods; Apple is discontinuing the use of PVC.

Wal-Mart, Target, Sears, and Kmart have agreed to phase out PVC goods. Packaging designers are ceasing the use of PVC from "clamshell" packaging of consumer electronics.

For a humorous introduction to concerns about PVC, the documentary Blue Vinyl tracks a woman's efforts to convince her parents not to use vinyl siding on their home.