A south Minneapolis dry cleaner leaking hazardous chemicals into a strip mall that includes a day-care center is under scrutiny from regulators threatening to take action if the contamination isn't stopped.

State regulators this spring found that the air in several businesses at the mall at 47th Street and Hiawatha Avenue S. contained high levels of perchloroethylene, known as perc, after initially discovering it in the underlying soil. An attempt to suck the gas from the soil failed to mitigate the problem, revealing that the machines in U.S. Cleaners were polluting the air.

Perc has historically been used for dry cleaning but is being phased out because of the adverse health effects. The city's Health Department learned of the problem a week ago and encouraged the owner to properly seal the store and the equipment, which it may shut down if the problem can't be fixed.

"We don't want children exposed," said the city's environmental health director, Dan Huff, adding that officials are pleased with the owner's response. "We want to minimize their exposure as much as possible."

People who are exposed to high levels of perc for many years may experience neurological problems and a higher risk of cancer. The state Health Department said in a fact sheet, however, that contamination levels in the Parkway Plaza mall were unlikely to be high enough to cause those types of health problems.

But the day-care center several doors down, primarily serving children of Somali descent between 6 weeks and 12 years old, gives the issue extra urgency. The city is meeting with parents at the day care, Rise N Shine, on Monday afternoon. Most of the children were attending graduations on Friday afternoon.

"They said it's not a large health risk," director Filsan Ismail said Friday. "But they said they will do everything possible [to fix the problem] because … there are children involved here."

The door was open and fans were spinning furiously on Friday at U.S. Cleaners, where a man at the counter referred all comments to the city. Of the nine dry cleaners using perc in Minneapolis, U.S. Cleaners uses the most, according to a list generated by the city Health Department. That number has decreased in recent years because of a city grant that aids businesses hoping to switch to more modern equipment. Some cleaners are also just storefronts that do their actual cleaning off-site.

About 40 percent of cleaners in the state still use perc, more so in outstate Minnesota, said Drenda Wendell, the executive director of the Minnesota Cleaners Association. Businesses generally do not install new machines using the chemical.

Huff said that the owner of U.S. Cleaners sealed up all cracks between his business and those next to his, which includes a tailor. They also replaced some missing bolts on one of the machines.

The Minnesota Department of Health says that perc levels of 40,000 micrograms per cubic meter have been shown to affect worker health over many years of exposure. Twenty micrograms per cubic millimeter is considered a residential baseline. The day care had 474 in April, and the tailor reached 13,600.

"What we're concerned about is an increased risk over time," said Jim Kelly with the Minnesota Department of Health. "But the risks are still quite low …. We don't think the children are at greatly increased risk over adults."

Occasionally, improper disposal of dry-cleaning chemicals creates soil and water contamination that sends vapors into nearby structures. But to have the chemical moving across shared commercial space is unusual, Kelly said.

"This is a huge concern," said City Council Member Andrew Johnson, who represents the area. "And I hope that moving forward we can make our city perc-free."

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