American chemical makers Dow Chemical Company and DuPont have cleared all regulatory approvals for their planned merger and set 31 August as the closing date for the US$150bn deal.

Shares of the newly formed DowDuPont would begin trading on the New York Stock Exchange on 1 September, the companies said in a statement on 4 August.

Earlier this month, DuPont paid nearly US$400M to settle two environmental lawsuits standing against the firm, although DuPont itself said the timing of the settlements was coincidental, reported Delaware Online on 4 August.

According to the news portal, DuPont paid more than US$50M in the largest environmental damages settlement in Virginia history to resolve a case centred around the release of mercury from its former facility in Waynesboro, which contaminated more than 100 miles of water in the South River and South Work Shenandoah River.

In February, DuPont also split a US$670.7M settlement with Chemours to settle 3,500 lawsuits related to the release of toxic perfluorooctanoic acid (PFOA) used in the production of Teflon, which was once one of DuPont’s most profitable products.

“We’re pleased to have reached a mutually satisfactory resolution in these decades-old matters. These actions are unrelated to the proposed merger with Dow,” said DuPont spokesman Dan Turner.

However, the chemicals maker was still facing another US$1.1bn environmental lawsuit, filed last year by the town of Carneys Point, New Jersey, wrote Delaware Online.

The lawsuit alleged that DuPont violated New Jersey by not cleaning its Chambers Works facility before transferring the site to Chemours when the company spun off from DuPont.

More than 45,000 tonnes of toxic materials – including PFOA, mercury, benzene and ethyl chloride – were dumped onto the Chambers Works site, according to the lawsuit.

The merger of Dow and DuPont, first announced in December 2015 and originally valued at US$130bn, was set to create three independently traded companies to focusing on agriculture, materials and specialty products.

DuPont, with a 214-year-long history, manufactures products for the petrochemicals, pharmaceuticals, food and construction sectors, while the 119-year-old Dow produces plastics, chemicals, hydrocarbons and agrichemicals.

Both companies supply GM seeds and pesticides/herbicides for crops such as canola, corn, rice and soyabeans.