September 6, 2007

Can Plastic Leach into Your Water?

By Tara Bozick, Victoria Advocate, Texas

One way to reduce the amount of plastic in our landfills might be to reuse plastic bottles, but that option carries its own health concerns. Some are concerned a reused bottle may leach chemicals into the water.

Any risk at this point is theoretical, said Dr. Martin Lorin, pediatrician at Texas Children's Hospital in Houston and professor of pediatrics for Baylor College of Medicine.

Because humans have not been tested or researched in this area, no evidence exists for harm caused by leached chemicals from the plastic bottles.

The major concern is phthalates, chemical agents used to soften plastic, Lorin said. These agents act as an estrogen hormone or estrogen blocker. Substantial animal data exists to support this, he said.

Lorin worries not so much about adults, but about developing fetuses and children.

"The major concern is the developmental issue," Lorin said. Nothing is yet known about its effects as a carcinogen.

Lorin advises not to reuse plastic water bottles or the heat food in any type of plastic in the microwave. "If heated, it can leach," Lorin said. "You don't want to reheat or thaw out frozen food in soft plastics."

Lorin recommends filtering water and putting it in a harder plastic bottle, such as a mountain bike bottle.

But hard plastic may leach too, said Dr. Winifred Hamilton, professor at Baylor College of Medicine. Hard plastic contains the polycarbonate component bisphenol-A, an endocrine disruptor that mimics estrogen.

This could affect brain development in children and reproductive function for both male and female adults, Hamilton said. Scientists would like to study the effect of these leaching chemicals on humans, she said.

Surveys of adult bodies show evidence of polycarbonates and other chemicals in human tissue, she said. The health effects are not known.

Baby bottles may leach bisphenol-A and babies' small bodies and developmental state make them more susceptible, Hamilton said.

She and other researches at Baylor would like to follow children from infancy to a few years of age to see any health effects from chemicals like pesticides, metals and other "bio-markers."

Hamilton said plastic water bottles are not made for long reuse and advises to not leave water sitting in plastic bottles for long periods of time. Heating or scrubbing the plastics also causes leaching, she said.

She refills her softer plastic water bottles, citing how companies have the ability to remove the phthalates.

"Is it really a problem?" Hamilton said. "Nobody knows, but there is enough evidence to be concerned."

Tara Bozick is a reporter for the Advocate. Contact her at 361-580-6504 or [email protected], or comment on this story here.