3M has temporarily shut down some operations at a factory in Belgium after environmental regulators there banned emissions of PFAS.

It appears to be the first time any regulator globally has moved to stop production of PFAS, a controversial class of chemicals that 3M pioneered decades ago.

Amid a dispute over water and soil pollution, the Flemish environmental agency issued a new safety measure on Oct. 29 that prohibits emissions of all forms of PFAS from 3M's factory in Zwijndrecht, a city in the northern part of the country in the province of Antwerp.

In response, 3M Belgium launched an appeal seeking an "urgent" suspension of the PFAS ban until the appeal is resolved, the company said in a U.S. securities filing. 3M acknowledged "uncertainties" over how long the ban will last.

The Belgian regulators' edict to stop PFAS production came after recent blood samples were taken from 800 people near the plant.

PFAS, short for per- and polyfluoroalkyl substances, are known for their nonstick and water-resistant properties and have long been used in products ranging from fabric protectors to firefighting foam.

But the so-called "forever chemicals" don't break down in the environment and can accumulate in blood. PFAS have polluted groundwater — including in Washington County — and have been linked to significant health risks, including certain types of cancer.

3M stopped making PFAS chemicals at the heart of the controversy — PFOA and PFOS — about 20 years ago.

But the company is facing a tidal wave of U.S. litigation over pollution related to those two compounds. And the U.S. Environmental Protection is discussing designating PFOA and PFOS as hazardous substances.

In Belgium, recent public health tests established increased blood levels of certain PFAS chemicals — including PFOA and PFOS. But those blood tests did not contain PFAS compounds that are currently made at the plant and have no negative health effects, 3M said in its appeal to Belgian regulators.

The Belgian plant is one of five PFAS manufacturing sites Maplewood-based 3M has around the world: the others are in Cottage Grove; Decatur, Ala.; Cordova, Ill.; and Gendorf, Germany.

The PFAS issue has been percolating in recent months in Belgium. Environmental officials of Flanders, the government region where the 3M plant sits, served both 3M's Belgium subsidiary and Maplewood-based parent 3M Co. with a "default notice."

Such a notice essentially warns 3M that Flanders deems the company to be violating its environmental regulations, and demands that 3M engage with its regulators to discuss remediation, abatement and the creation of a fund to pay for environmental damages and potential health damages.

In late September, 3M committed $145 million over three years to remediate PFAS-related environmental issues near the Belgian plant.