Dow Chemical Co. and DuPont Co. are reportedly close to announcing a merger that would create the world’s second-largest chemical company whose $120 billion value would trail only BASF SE.

The deal would also create the largest seed and pesticide company, according to both The Wall Street Journal and Bloomberg News. The size of the deal, thought to be the largest in the chemical industry’s history, could require the combined company to break into two or three separate businesses.

The Wall Street Journal describes the talks as “advanced” and says the deal could be announced in days.

DuPont spokesman Daniel Turner said the company does not comment on rumors or speculation.

The impact in Louisiana, where Dow has six locations and DuPont one, is unclear. And some say the deal might not come together at all.

“It’s just unbelievable what’s going on. … This whole thing is so complicated that no one can understand it,” said Randy Peterson, a Baton Rouge consultant who tracks Gulf Coast industrial developments.

In the past year, Dow has struck deals to shed a big chunk of its chlorine operations, including those in Plaquemine, to Olin Corp. for $5 billion, and sold its post-harvest specialty chemical business, AgroFresh, for $860 million. DuPont also sold its neoprene business in LaPlace to Denka Performance Elastomer LLC for somewhere between $84 million and $117 million. Meanwhile, DuPont spun off its performance chemicals business into a new company, Chemours Inc.

Both companies are worth nearly the same amount, with Dow valued at about $59 billion and DuPont at almost $58 billion. Dow has around 51,000 employees, while DuPont has around 62,000.

But the combined company may have to sell parts of some businesses or create separate ones for materials and agricultural products, among others.

Kent Holsing, president of Dow North American Labor Council, a group made up of local unions to advocate for Dow workers, said at this stage everything is just guesswork and speculation.

But whenever companies merge, the people who benefit are shareholders and executives, Holsing said. The workers and the communities where they live do not.

One of the things that happens after a merger is that companies cut costs, and that typically means people, Holsing said. The layoffs — and there will be layoffs if there is a merger — will hit hardest in white-collar positions, such as administration and support.

“We don’t know how much overlap there is between Dupont and Dow Chemical. … But you won’t have multiple HR departments. You won’t have multiple R&D departments,” Holsing said.

Dow’s sites include:

LOUISIANA OPERATIONS: One of the state’s largest petrochemical facilities, which includes a 1,500-acre manufacturing facility near Plaquemine and brine operations in Grand Bayou, and close to 3,000 employees and contract workers. The site makes more than 50 different chemical products, such as chlorine and polyethylene, that are used in cosmetics, detergents, solvents, pharmaceuticals, adhesives, and plastics packaging. At Grand Bayou, Dow mines underground salt and water to produce a brine used in making chlorine.

ST. CHARLES OPERATIONS: A 2,000-acre manufacturing site in Hahnville, with more than 100 Dow employees and 1,500 contract workers. Products made there are used in plastics, insecticides, film and fabrics, among other things.

WEEKS ISLAND: Part of Dow’s Optical and Ceramic Technologies business segment: The Iberia Parish facility employs 82 Dow and contract workers. Production process is used in making specialized windows, laser lenses and other optical elements.

DOW STERLINGTON: The 80-acre site in Ouachita Parish produces more than 40 specialty products used in paints, coatings, metalworking fluids and water treatment. The site employs 275 Dow and contract workers.

AMERCHOL GREENSBURG: The 50-acre site in St. Helena Parish employs 35 people and makes products found in skin and hair-care products, detergents, makeup and toiletries.

DuPont’s last property in Louisiana is the LaPlace facility that makes materials used to make Kevlar.

Follow Ted Griggs on Twitter, @tedgriggsbr.