Martin Wagner and Jorg Oehlmann of the Goethe University in Frankfurt, Germany, said in an analysis of commercially available mineral waters, researchers found evidence of estrogenic compounds leaching out of the plastic packaging into the water.
What's more, the chemicals result in an increased development of embryos in the New Zealand mud snail, the researchers said.
The findings, published in the journal Environmental Science and Pollution Research, show for the first time that substances leaching out of plastic food packaging materials act as functional estrogens.
The researchers analyzed 20 brands of mineral water available in Germany -- nine bottled in glass, nine bottled in plastic and two bottled in paperboard boxes coated with an inner plastic film.
"We must have identified just the tip of the iceberg in that plastic packaging may be a major source of xenohormone -- man-made substance that has a hormone-like effect -- contamination of many other edibles," the researchers said in a statement. "Our findings provide an insight into the potential exposure to endocrine-disrupting chemicals -- low-dose exposure to chemicals that interact with hormone receptors that may interfere with reproduction, development and other hormonally mediated processes -- due to unexpected sources of contamination."