Tinley Park Company Pleads Guilty To Exposing Workers To Arsenic

TINLEY PARK, IL — A south suburban company is facing almost half a million dollars in fines after pleading guilty to a charge that accused Tinley Park-based U.S. Minerals of exposing its employees to arsenic.

U.S. Minerals was sentenced to pay a $393,200 fine on Friday and agreed to be placed on probation for five years, according to court records. The charges were brought in federal court in Montana, where the company owns a location in Butte.

According to prosecutors, the company poisoned its workers by exposing them to inorganic arsenic despite numerous warning from officials. U.S. Minerals used the plant in Montana to turn waste from mining into roofing materials such as shingles. During the process, arsenic can run off metals or wood while they're being treated.

Long-term exposure to arsenic can cause skin and lung cancer.

The plant was closed in June 2021 after the guilty plea to negligent endangerment, a misdemeanor violation of the federal Clean Air Act. Now, U.S. Minerals must monitor the health of former Montana employees to check for elevated levels of arsenic.

According to court records, the National Institute of Occupational Safety and Health first tested six employees for arsenic poisoning in 2016. Five of them showed high levels of arsenic and were provided with face coverings but not given a place to wash arsenic off their hands if they came into contact with it.

For U.S. Mineral plants still operating in Illinois, Kansas, Louisiana, Wisconsin and Texas, the Environmental Protection Agency and OSHA will be given "increased oversight" into operations and outputs for the next five years, according to the plea agreement.

While the base in Montana was permanently closed in June, Montana's department of public health ordered the plant to close temporarily in February 2019 after two more workers revealed high levels of arsenic in their urine.