Ongoing water testing results in Seattle Public Schools show elevated levels of toxins in 35 schools including five in the Ballard area; Adams, Ballard High School, Greenwood, Whitman and Whittier.

Lead levels in some of the water samples were more than 10 parts per billion, the school district's mandated standard. Some registered higher than the Environmental Protection Agency's standard of 20 parts per billion.

School district administrators and health officials have said it's unlikely the health of students or school staff has been jeopardized.

According to the Environmental Protection Agency, even children who appear healthy can have dangerous levels of lead in their bodies. Lead may cause behavioral problems, learning disabilities, seizures and death. Children 6 and under are at most risk because their bodies are growing quickly.

"Our experts believe that lead levels can build up when water stands unused in pipes for many days," said superintendent Raj Manhas.

The district was scheduled for a routine water test in 2007, but because the district already had samples from the last spring's arsenic testing, a decision was made in September to test early to save money.

The district was surprised to find many of the contaminated supplies came from new schools that do not have lead pipes, fixtures or solders. The newer schools also showed less than 10 parts per billion when previously tested in 2004.

District officials said the problem is likely one of plumbing, but it's still not clear where the toxins are coming from. Testing is underway to determine the source and results are expected in the next several weeks

Meanwhile, 323 affected water fountains and sinks have been taped off. The district is providing bottled water for school staff and students in the interim.

Since parents raised concerns in 2003 after noticing discoloration in the drinking water at some schools, the district has begun testing water more often and has spent $13 million to replace water pipes and fixtures. Seattle School's standard for lead is also one of the toughest in the nation.