Boxford school's water tainted

Students at a Boxford elementary school are drinking water only from bottles as state health officials investigate how traces of a chemical found largely in explosives slipped into the school's water supply.

Officials from the Massachusetts Department of Environmental Protection on Friday discovered elevated levels of perchlorate, a contaminant found in fireworks and rocket fuel, in the drinking water at Spofford Pond School, which serves 560 students in grades 3 through 6.

When ingested in high doses, the chemical can pose significant health risks to children, pregnant women, and infants, officials said.

The overall danger of the chemical, which has been found in nine other Massachusetts communities since 2002, has been in dispute among environmentalists, regulators, and the US Department of Defense.

Still, state and school officials have decided to err on the side of caution.

''As of this morning when we opened, we had bottled water available to those for drinking," said Boxford Superintendent of Schools Bernard F. Creeden.

It is safe for children and staff to use tap water to wash hands and use the toilets, he added.

''We have been advised not to use the dishwasher in the kitchen," said Creeden, noting that students are using Styrofoam lunch trays and that food has been carefully prepared without excess water. ''We are still awaiting the advice from the DEP on the cleaning of pots and pans," he said.

Routine testing of Spofford Pond School's water supply over the past two weeks has shown levels of perchlorate in the water at 1.5 parts per billion. In Massachusetts, the advisory guideline for the contaminant stands at 1 part per billion for children ages 12 and under, pregnant or nursing mothers, and those with thyroid problems, state officials said.

For adults, the guideline is 18 parts per billion.

There are no national standards for just what level of perchlorate-tainted water is considered safe to consume. Earlier this year, the National Academy of Sciences released a report saying perchlorate was far less toxic to humans than first believed.

High doses of the chemical, which was largely detected near contaminated military bases, is believed to interfere with the normal function of the thyroid gland, and can cause brain damage among other adverse effects, state health officials said.

Still, Massachusetts health officials have conducted their own research, said Edward Coletta, spokesman for the state Department of Environmental Protection, and officials have set an interim guideline at 1 part per billion for children 12 and under, pregnant or nursing mothers, and those with thyroid problems.

That limit is among the strictest in the country. In California, the standard is 6 parts per billion.

Boxford is the 10th Massachusetts community to test positive for the chemical since 2002, when trace levels of the contaminant were found in Bourne test wells, probably from the adjacent Massachusetts Military Reservation, where grenades and rockets containing the chemical were used. The other towns are Boxborough, Williamstown, Westport, Millbury, Tewksbury, Westford, Southbridge, and Hadley.

In communities where perchlorate has been discovered, officials typically have stopped drawing water from contaminated wells or adopted other measures.

Officials in Boxford are working to find the source of the chemical. ''We are just trying to be protective of the public health, especially for those in the sensitive group, such as infants and nursing mothers," said Coletta. ''We are working with local officials and the Board of Health to determine our next steps."