BATON ROUGE - Residents near the Denka and DuPont chemical plants in Reserve, Louisiana have known the words "ethylene oxide" and "chloroprene" for years, but they never truly wanted to know what they mean.

On Tuesday, the U.S. Environmental Protection Agency finalized a ruling that will significantly reduce the amount of toxic air pollution emitted from chemical plants. The ruling affects 218 chemical plants across the country, 51 of which are located in Louisiana. The EPA's decision to reduce emissions comes after longstanding environmental justice efforts and is expected to reduce elevated cancer risk in communities by 96 percent.

"It's been long overdue," said Mary Hampton, a resident of Reserve, who lives within 2,000 feet of the plant.

Hampton has lived in Reserve for 80 years, she hardly knows a life without a chemical plant in her backyard. She worked at a plant from '75 to the early 2000s. Hampton said has never been diagnosed with cancer but that the rest of her family and neighbors have died from cancer, which she claims is a direct result of the Denka and DuPont chemical plants.

"Everybody, not just my family members, everybody in my area is dying with the same types of cancers, suffering the same sicknesses," Hampton said. "We've lost so many people in our area, not just my family."

Hampton said she sees the same types of cancer be diagnosed within her neighborhood: bone, kidney, stomach and breast cancers are not unfamiliar diagnoses in the area. She said she attributes the terminal cancers that have claimed her loved ones' lives to the air they breathe in, and have for so many years.

"You walk around with little nebulizers in your purse and pocket all the time cause sometimes you can't breathe," Hampton said of a normal day. "This has been going on for years and years and years and years."

During a winter day, Hampton's neighbor and friend, Lydia Gerard, said she can see the back of the chemical plant from her porch. Gerard has lived in Reserve most, if not all, of her life and said she has lived "close enough" to always see the plant — it's her view.

"They're saying it's not environmental racism," Gerard said. "But we can see that a lot of it is... Whose along the river? Mostly Black people, low-income people that don't have the opportunity to move and that's another question that we get. 'Why don't you move?' Why should I move? I was here before the plants got here."

In 2015, the EPA both educated and revealed to residents around the Denka plant just how harmful the emitted toxic chemicals were, noting the elevated risk for cancer. Gerard said she lost her husband to cancer and just survived a bout of cancerous tumors in December, both of which she attributes to the chemical plants.

"It was just astonishing of how high the emissions were in reference to what the standards," Gerard said, gesturing with air quotes. "Well, not really standards... What they thought they should be, the amount that we should be exposed to."

Environmentalist Wilma Subra, also a technical advisor at the Louisiana Environmental Action Network, said the new ruling gives chemical plants two years to tighten their emission standards.

The new ruling changes emission standards by one decimal point, from 0.2 to 0.3 emission concentration. Subra said concentrations of chloroprene have long been in excess.

"They knew that chloroprene exceeded 0.2, and they determined that a woman, who is pregnant, when she gives birth to her baby and the baby has its second birthday, that baby has been exposed to 70 years of exposure to chloroprene," Subra said and then paused. "Totally unacceptable."

One decimal point may not seem like much, but it's a win for the environmental justice community, according to Subra. For those like Hampton and Gerard, it's a small step in the right direction to solving a problem that has already dictated so much of their lives.

In a statement, the Louisiana Chemical Association responded to the EPA's ruling, saying they have "long argued" the flawed risk assessment process for ethylene oxide. The LCA said it will closely review the rule and its potential implications for its member companies.

"(Tuesday) is a major accomplishment, but it's not for the community because the community has to live for another two years with the high concentrations in the air they're breathing," Subra said.

"Regulating is the step that should have been taken years and years and years ago," Hampton said, reflecting on a lifetime of being neighbors to a chemical plant. "Signing off on the ruling was a blessed thing to do."