One must consider the whole package.

Mineral waters in glass bottles were less estrogenic than waters in plastic bottles. Specifically, 33% of all mineral waters bottled in glass compared with 78% of waters in plastic bottles and both waters bottled in composite packaging showed significant hormonal activity.

By breeding the New Zealand mud snail in both plastic and glass water bottles, the researchers found more than double the number of embryos in plastic bottles compared with glass bottles. Taken together, these results demonstrate widespread contamination of mineral water with potent man-made estrogens that partly originate from compounds leaching out of the plastic packaging material.

The authors conclude: "We must have identified just the tip of the iceberg in that plastic packaging may be a major source of xenohormone* contamination of many other edibles. Our findings provide an insight into the potential exposure to endocrine-disrupting chemicals due to unexpected sources of contamination."

There are a lot of confused endocrine systems it seems. I expect we'll be hearing more about this.