But complete disclosure is rare. An EWG study released at the hearing checked 188 bottled water brands and found that less than 2 percent disclose all three basic facts about their water, on the label or in a Web site. Those facts are the water’s source, how it was purified, and what contaminants remain.

The study found these contaminants in the blood of all five participants: flame retardants, Teflon chemicals, synthetic fragrances, the plastics ingredient bisphenol A (BPA) and the rocket fuel component perchlorate.

Participants tested postive for 35 to 60 percent of the 75 chemicals on the list. Each also showed a high level of at least one controversial unregulated chemical.

In 2004, the US Environmental Protection Agency reported that diesel fuel, used as a fracturing fluid, results in toxic compounds being left underground, “likely to be transported by groundwater supplies.”

In the wake of EWG’s report, New York City Councilman James F. Gennaro demanded the state acknowledge its lack of testing in the matter and perform tests to see whether the proposed chemicals would be dangerous to the NYC water supply.