(NEW YORK) -- Toenail clippings could be the key to discovering if thousands of residents of Garfield, N.J., have been exposed to a toxin spill 30 years ago that could cause cancer.
"Toenails grow slower than fingernails or than hair so you can track or detect chronic exposure in toenails," Judith Zelikoff a professor and research scientist at New York University's School of Medicine, told ABC News.
One millimeter of toenail can reveal information up to 18 months of exposure.
The risk of contamination comes from a 1983 leak where thousands of pounds of hexavalent chromium seeped out of a tank at a factory surrounded by houses and apartment buildings.
Scientists say only 30 percent of the leak was cleaned up, and 10 years later, chromium was found in area basements and a firehouse.
Hexavalent chromium is a metal that is well-known as a carcinogen. Many people recognize the name from the film Erin Brokovich, where the same toxin harmed the people in the California neighborhood that surrounded the leak.
In the film, the people were sickened from drinking contaminated water, but scientists believe the people in New Jersey are at risk of inhaling it or touching it, not drinking it.
"Many people are concerned and, unfortunately, many people are not even aware," said Zelikoff, the community outreach director for the project.
"Up until this point, there was no work done in terms of human exposure," she said. "We're hoping and we truly believe that there is not going to be a lot of people that are exposed, but we're doing this primarily to relieve anxiety from the people who live there."
The underground plume is about three-quarters of a mile wide and a little less than a mile long, according to the Environmental Protection Agency. The "area of concern" covers more than 600 homes and businesses with the potential of more than 3,700 people being possibly effected, Zelikoff said.
Residents of the area are being given kits that include a stainless steel nail clipper (cheap nail clippers may contain traces of chromium), a plastic bag for the clippings, nail polish remover, alcohol swabs, instructions and an envelope for the clippings. The results will take about five weeks.
Samples are being collected from people ages 18 to 65 who are non-smokers and do not take chromium supplements. The people must have been residents of Garfield for at least two years.
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