Polycarbonate water bottles have received plenty of bad press for releasing potentially toxic compounds into unsuspecting drinkers, but there may be another culprit: everyday plastic packaging.

A German study of commercially-available bottled water found contamination by chemicals that mimic natural sex hormones. When the researchers raised snails in the water, they bred with extreme rapidity — a warning sign that the chemicals were active. Contamination levels were twice as high in brands packaged in plastic instead of glass, suggesting that plastic was the culprit.

Many additives used to make plastic more durable and elastic are known to have endocrine-disrupting effects in laboratory tests, and the average developed-world body is suffused with these so-called xenohormone residues. Research suggests that the consequences, though not fully understood, are real: fetal xenohormone exposures have been linked to reduced virility in boys and the early onset of puberty in girls. The effects may even linger in subsequent generations.

It wasn't known, however, whether xenohormones entered human bodies from food-packaging plastics in addition to other already-established sources, including polluted air, personal care products and food additives. The latest findings, published recently in Environmental Science and Pollution Research, suggest that packaging is at least partly responsible.

"Our findings provide first evidence for a broad contamination of mineral water with xenoestrogens," write the researchers. "We may have identified just the tip of the iceberg."* *

*Citation: "Endocrine disruptors in bottled mineral water: total estrogenic burden and migration from plastic bottles." By Martin Wagner and Jörg Oehlmann. Environmental Science and Pollution Research, Vol. 16 No. 2, March 2009. *

Image: Flickr/Shazari

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