CHICAGO (CBS) – Water fountains are shut off at a Woodstock school after tests show elevated levels of arsenic.

Greenwood Elementary School gets its water from an on-site well. The district is bringing in bottled water, and staff has been told by the Illinois Department of Public Health to stop using school water for cooking and drinking.

Elevated levels of arsenic have been found in the water at Greenwood Elementary School in Woodstock.

Greenwood parents were notified of the issues on Wednesday.

State health officials say arsenic is not easily absorbed through the skin, so students can still wash their hands in school restrooms.

Arsenic is found naturally in the ground, and contaminates some wells in Illinois, including McHenry County, according to IDPH.

Water at Greenwood Elementary School is tested on a quarterly basis, according to a release from the school district. Two samples were taken in November and showed results of 32 parts per billion and 18 parts per billion. District staff were made aware of those results after the school got a phone call from a laboratory employee on Wednesday.

In 2001, the U.S. Environmental Protection Agency set a standard for arsenic levels in public drinking water systems at 10 parts per billion, a reduction from the previous standard of 50 parts per billion.

District officials say they have yet to receive official documentation on those results from IDPH but expect to receive a letter soon.

According to the school district, a representative from IDPH told the system arsenic is not considered an immediate health threat such as e coli or other bacteria, but there are health concerns with long-term exposure to arsenic.

The district says it is making improvements to its filtration system and is expected to have new water test results next week.