3M has again halted PFAS manufacturing in Belgium after high levels of the "forever chemicals" were detected around the plant.

Belgian authorities are investigating after learning last week "3M was still emitting relevant amounts of PFAS into the ambient air," according to a government website translated from Dutch. "The PFAS emissions end up in the environment and cause additional pollution, in this case mainly in the groundwater."

Maplewood-based 3M has pledged to phase out production of PFAS by the end of 2025, but it is still big business. The family of chemicals do not break down in the environment and are used by key customers in the semiconductor and automotive industries.

Through the first half of the year, 3M's PFAS sales totaled $677 million.

In a federal securities filing this week, 3M said the Belgian shutdown could have a "significant adverse impact on 3M Belgium's normal operations and the company's businesses that receive products and other materials from the facility."

3M may try to speed up its exit from PFAS manufacturing in Belgium as a result, according the U.S. Securities and Exchange Commission filing. Other manufacturing processes are continuing.

The plant in Zwijndrecht was at least partially shuttered from late 2021 to mid-2022 after high levels of PFAS were found in nearby residents' blood. 3M had pledged $600 million for remediation and to resolve pending lawsuits over the contamination.

Now the company could be facing new repercussions from the government in Flanders, the region of Belgium where the plant sits.

Flemish environment minister Zuhal Demir told Belgian media this weekend "all options will be examined over the coming weeks."

"I have also ordered an investigation to determine how long 3M had known about this without informing the government," Demir said, according to the Brussels Times. "In this case, we will not hesitate to prosecute the company for violating its obligation to protect the environment. In my view, any legal step can be taken after these events, including the withdrawal of the company's environmental permit."

3M said in the SEC filing it self-reported the emissions issue. The duration of the idling is uncertain, and "the company is unable to predict the ultimate scope and extent of any negative impact to the company's operations."