It's rare that Minnesota goes to the extent of temporarily shutting down a business for posing an immediate risk to health and safety. But the events unfolding at Water Gremlin in White Bear Township show that such action indeed was merited, and that more is needed.

Closed by state order since Monday, the manufacturer of lead battery terminals and lead fishing tackle has been a persistent violator of state rules. Earlier this year it was hit with one of the largest fines in state history by the Minnesota Pollution Control Agency for years of excess emissions of a known human carcinogen. Now the state has determined that the company has jeopardized the health of at least a dozen children of its employees who have elevated levels of lead in their blood, two at levels that may cause permanent damage.

Gov. Tim Walz, in explaining the state's move, told an editorial writer that efforts to work with the company voluntarily had failed. When that happens, he said, "Our first responsibility is the safety and security of Minnesotans."

A Ramsey County judge on Friday ruled the company could reopen Tuesday, but the reprieve could prove brief if the company fails to take the situation seriously. Judge Leonardo Castro wants the parties back in court Wednesday, and he said he will not hesitate to shut operations if Water Gremlin falls short in its cleanup commitments.

"We consider Water Gremlin a wake-up call for Minnesota," Health Commissioner Jan Malcolm told an editorial writer. "Lead is a significant, population-wide health question." Federal standards have not kept pace with evolving science, she said, which shows that there is no safe lead level for humans. "Lead is not like the flu," she said. "You don't know you're suffering effects right away." State health officials say 80% of workers whose tests could be linked to Water Gremlin showed elevated blood lead levels. The state is awaiting the results of another 100 blood tests.

The Star Tribune Editorial Board has noted before the need to reduce lead in the environment, recently pushing for the elimination of lead fishing tackle and ammunition because of the dangers of lead to wildlife and the environment. But an even more immediate threat is posed by a business that jeopardizes its employees and children by unnecessary exposure.

Medical science has determined there is no safe blood lead level for humans. None. Whether ingested, inhaled or absorbed, lead accumulates in the body, gravitating toward the brain and bone marrow. The greatest danger is to children. They can suffer devastating effects, including seizures, brain damage and developmental regression. But lead harms adults as well, and evidence is mounting that even low levels can affect health. At least 10 blood tests linked to Water Gremlin employees in recent years have showed lead levels high enough to affect cardiovascular and reproductive health.

The company has already gotten more than its share of second chances. Ramsey County found elevated lead levels in the blood of employees' children in 2017. The county tried working with the company on voluntary remedies. A year later, blood levels had not fallen. For 15 years Water Gremlin failed to file accurate emissions data. In March it was fined $7 million for years of excess emissions of trichloroethylene, a degreaser linked to increased risk of kidney and liver cancer in humans. Water Gremlin sits amid four lakes, several parks and a number of residential homes. In its investigation, the MPCA also found pollution in the soil, soil vapor and shallow groundwater near the plant.

Malcolm has said that in addition to better policies, training and enforcement, Water Gremlin needs "significant physical changes" to minimize risk at the plant. The state should insist the changes take place.

Walz noted that other businesses in Minnesota handle lead, but they pass their inspections and take the needed safety precautions. "There are businesses doing this right," he said. When a business repeatedly fails to do so, he said, "I'm going to err on the side of public health and safety."