THIRTEEN-MONTH-OLD Solange Dorsainvil plays with toys made from wood and cloth, drinks from a Swiss-made aluminum sippy cup and teethes on kale stems and celery.

Her life is as plastic-free as her mother, Celina Lyons, can make it.


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This article was previously posted with an incorrect publication date. It appeared in The Times on Sept. 10, 2007. —



Celina, a Berkeley-based acupuncturist, has become increasingly worried about the possible toxic effects of plastics. "I remember hearing -- I don't remember when -- that my Nalgene [water] bottle was no longer safe," Lyons said. Once pregnant, she stopped storing food in plastic and cut back on plastic wrap. She sought plastic baby bottles free of a chemical called bisphenol A and teething rings free of chemicals called phthalates. (She failed to find the latter.)

"It's hard to just be a relaxed parent," Celina says. "You want to do what you can to make things as safe as possible."

More and more consumers -- new mothers are leading the pack -- are expressing concern about potentially toxic chemicals in plastic products. Baby blogs are abuzz with warnings about chemicals in baby bottles and toys. Retailers say that demand for glass baby bottles is higher than it's been in decades and that shoppers are snatching up bottles and training cups made from plastics without bisphenol A. California lawmakers have taken notice: Last week, the state Legislature passed a bill to ban certain phthalates in plastic items meant for children younger than 3.

Recent widely publicized studies have shown that plastics are not only ubiquitous in the environment (marine researchers have shown that plastic debris outweighs zooplankton in remote parts of the Pacific), but are found in the bodies of nearly all Americans too. Scientists have hypothesized that chemicals in certain plastics may be linked to such conditions as asthma and even obesity. But most of the research, and the strongest evidence, points to effects that certain plastics chemicals appear to exert on the reproductive system. Findings are still considered preliminary (existing studies are small and few), but reports are enough to make consumers ask: Are plastics safe?

"Unfortunately," said Dr. Philip Landrigan, a pediatrician and chairman of the department of community and preventive medicine at the Mount Sinai School of Medicine in New York, "we're in the terrible position of having to say that we mostly don't know."

Antonia Calafat, a lead research chemist at the Centers for Disease Control and Prevention, has spent the last several years measuring levels of phthalates -- chemicals used to make plastics pliable -- in the U.S. population. The chemicals, studies show, appear in nearly all Americans.

But while phthalates and other chemicals used in plastics have been shown to be toxic to animals, "in humans, the data are still inconclusive," Calafat said.

In fact, when it comes to humans, the data are nearly nonexistent. Very little research has examined the health risks associated with consumer use of plastics. And because of suggestive evidence from studies of lab animals, much of that research has focused largely on chemicals in two types of plastics: those marked with recycling No. 3 and No. 7.

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PVC ingredient a problem

Plastic No. 3, polyvinyl chloride or PVC, was one of the earliest plastic chemicals to be linked to cancer. Studies dating back to the 1970s showed that PVC factory workers suffered an increased risk of a rare form of liver cancer -- an effect that had been demonstrated earlier in animal experiments.

The toxic agent, it turned out, wasn't the finished product; it was a PVC building block, a chemical known as vinyl chloride monomer. Vinyl chloride monomer poses no threat to people who use finished PVC products. (The monomer, unlike a PVC product, is small enough to be inhaled; in the body, it gets broken down into chemicals thought to damage genetic material.) More recent research, however, indicates that other components of PVC -- phthalates -- may pose health risks to the end users of the plastic.

Phthalates are added to normally rigid PVC to make soft products, including the plastic bags that store blood, plasma and intravenous fluids; feeding, breathing and dialysis tubes; catheters; respiratory masks; and exam gloves. Phthalates are also found in children's toys, vinyl floors, wallpaper, shower curtains, vinyl bibs and countless cosmetics, including lotions, shampoos and nail polish.

About a decade ago, CDC researchers figured out how to detect small levels of the breakdown products -- or metabolites -- of phthalates in human urine. Since then, they've been monitoring levels of the chemicals in Americans and collaborating with academic researchers to find possible associations between phthalate levels and disease.

In laboratory animals, high doses of phthalates cause a conglomeration of health effects that suggest the chemical may either block the activity of male sex hormones (such as testosterone) or hamper their synthesis in the developing embryo. The so-called phthalate syndrome in lab rodents is characterized by lowered testosterone levels; a shortened distance between the anus and scrotum; testes that fail to descend; reduced sperm counts; and defects in the urethra, prostate and seminal vesicles.