The state of New Hampshire sued 3M Co., DuPont and six other companies this week for allegedly polluting that state's drinking water with a class of PFAS chemicals once widely used to make nonstick coatings, fire fighting foams and a host of consumer products.

The lawsuits filed Wednesday are the latest in a string of litigation filed by cities, counties or states claiming harm from the chemicals, some of which 3M made for decades but ceased producing in 2000.

In addition to 3M and DuPont, New Hampshire is targeting the DuPont spinoff Chemours, as well as Tyco Fire Products, Chemguard, Buckeye Fire Equipment Co., National Foam Inc. and the United Technologies subsidiary Kidde-Fenwal Inc.

The state accused the companies of irresponsibly making, using or distributing the chemicals, which are formally known as perfluoroalkyl and polyfluoroalkyl substances (PFAS). The compounds were used in Scotchgard, Teflon, degreasers, firefighting foams and many household and industrial products.

New Hampshire Attorney General Gordon MacDonald accused the companies of contaminating the state's drinking water with the chemicals and of failing to warn the public of their known "dangers."

"The action we are taking today is intended to ensure that those responsible for the PFAS contamination to our state's drinking water supplies and other natural resources are held accountable," MacDonald said in a statement.

In a statement Thursday, Maplewood-based 3M said it "cares deeply about the safety and health of New Hampshire's communities. 3M acted responsibly in connection with products containing PFAS and will vigorously defend its environmental stewardship."

Other companies sued this week denied misusing any chemicals, while others insisted they did no business in the state of New Hampshire.

In recent years, the Environmental Protection Agency and other researchers have reported possible links of high levels of exposure to the chemicals to several possible health problems, including low birth weights, liver damage, kidney and testicular cancers, cholesterol changes and thyroid problems.

During the past 20 years, the EPA has slowly reduced the levels of PFAS chemicals it now deems safe for humans to consume. Various companies have taken different approaches to the fall out from the long lasting chemicals. Some provided drinking water to affected residents. Others sold their businesses or ceased production.

In February 2018, 3M agreed to pay the state of Minnesota $850 million to settle a lawsuit alleging 3M's chemicals leached underground and contaminated the drinking water near its Chemolite plant in Cottage Grove and near disposal sites in Oakdale and Woodbury in the East Metro region.

3M said it expects to pay the bulk of that settlement over four years.

Last week, 3M Co. also agreed to pay the city of Lake Elmo $2.7 million and give it 180 acres of farmland to settle that city's nearly decade-old claims that 3M's PFC chemicals contaminated drinking water and forced costly fixes.

3M's stock price slid 83 cents to close at $159.75 a share on Friday.