Questions linger over the potential health and environmental impact of the derailment of a train carrying hazardous chemicals near East Palestine, Ohio, earlier this month.

Some residents have reported headaches and rashes in the aftermath of the incident and have grown frustrated with the response from the rail company, Norfolk Southern, and public officials.

The Environmental Protection Agency maintains that the air is safe and that the agency is continuing to monitor the situation. The EPA says levels of the chemical causing the reportedly noxious smell are not high enough to impact the community's health.

What happened in East Palestine is a cruel reminder of what can happen for millions of people who live near railways throughout the U.S., said Jennifer Sass, a senior scientist in the health and environment program of the the Natural Resources Defense Council, environmental nonprofit.

There is "a really big risk" of what occurred in East Palestine happening in other communities, Sass said.

"Rail lines crisscrossing the country are carrying hazardous materials, including materials that are explosive, and including materials that will become airborne if they're released," Sass said.

Just this week another Norfolk Southern train carrying at least one car with liquid chlorine derailed outside of Detroit. In that case, no chemicals were released, local public safety officials said.

But there are things that the industry, individuals and their communities can do to better protect themselves from potential hazards of similar chemical spills, Sass and other health and chemical safety experts told NPR.

From 2015 to 2022, the Federal Railroad Administration investigated 110 train derailments with a hazmat spill

Though the risk of a crash and hazardous spill is deemed high by chemical safety experts, the Association of American Railroads (AAR) says "more than 99.9% of all hazmat moved by rail reaches its destination without a release caused by a train accident."

The U.S. freight rail network runs on almost 140,000 route miles, according to the Federal Railroad Administration. And U.S. railroads "typically transport more than two million carloads of hazardous materials each year, including many chemicals that are considered hazardous," according to the AAR.

From 2015 to 2022, the Federal Railroad Administration investigated 110 train derailments which resulted in a hazmat spill or release, according to data reviewed by NPR. No deaths were recorded in any of these derailments.

The agency doesn't investigate every derailment, however, and it has certain criteria for doing so.

The National Transportation Safety Board, which is investigating the derailment in Ohio, doesn't look into every derailment or other incident. That means the NTSB doesn't keep a definitive listing of events it didn't investigate, an agency spokesperson told NPR.

The risk, unfortunately, is not just with railways. There are chemicals also being transported by tanker trucks and by air, Nellie Brown, the director of workplace health and safety programs for the Worker Institute at Cornell University, notes.

"It's not like, [accidents are] impossible. These things do happen. And when you're looking at these things happening near residential areas, you naturally as a community need to have emergency response plans in place," she said.

Planning ahead with the community

The AAR says extensive work has been done to improve tank car designs to prevent hazardous spills. Railroads are also involved in training thousands of first responders annually. When derailments do occur, the association says emergency personnel have access to information on what is in rail cars and how to respond to it.

"These efforts — coupled with ongoing investment, technology, employee training, improved operating practices and community outreach efforts — have lowered hazmat accident rates by 55% since 2012," the organization claims.

But if this is a concern in your community, Sass recommends proactively working with local governments to try to make sure there's a response plan readily available. First responders, hospitals and train companies should know about this plan and there should be a way to alert the community quickly and efficiently and in multiple languages that are relevant for the population, she said.

What's most important is that the community is given the most up-to-date information when these accidents involving hazardous chemicals happen, Sass said.

"First responders and local health departments, local environmental agencies, and physicians, health care workers — all of them need accurate, timely information" to be able to properly respond and keep each other safe, she said.

Preparing your home ahead of time

There are things individuals can do on their own to protect themselves and their families from risks of hazardous air or water following a chemical spill, said Dr. Mary Prunicki, the senior director of air pollution and health research at Stanford Medicine.

"I think being prepared is the key thing," she said.

Prunicki encourages homeowners to check their indoor air quality. That way they know what conditions should be like and are better aware of when something is off. There are several ways to do this, ranging from purchasing an indoor air quality monitor to hiring a professional to conduct a check.

She also encourages checking frames around doors and windows and looking over furnace and air filters to be sure they are working effectively, "so that if you are indoors, you have the best possible environment regardless of what's going on outside," Prunicki said.

"If possible, have access to an air purifier or the ability to get one if needed quickly," she added.

For people who have chronic health issues like heart or respiratory problems, it's good practice to have medications on hand in case a quick evacuation is necessary, she said. The Centers for Disease Control and Prevention also encourages having a "to go" bag ready for family members and pets if emergency strikes.

What to do if disaster strikes

When a chemical emergency strikes, the CDC says communities will likely hear orders on what to do from emergency officials on the radio, TV and mobile news apps, or from text alerts via the emergency alert service.

If the order is to stay indoors, Sass encourages people to keep windows closed after receiving an alert.

The CDC has a six-step guide for when communities are ordered to shelter-in-place. The agency strongly urges keeping abreast of all updates from public safety officials during the crisis.

"Staying put for chemical emergencies is different from shelter-in-place for severe weather or tornadoes or radiation or nuclear emergency. You should seal off your space from outside air as much as you can," the CDC says.

That entails choosing a "safe room" for family members to easily block off any outside air. To do this, use duct tape, towels and plastic sheets to seal out chemical agents and target window air conditioners, exhaust fans, stove and dryer vents, and all doors and windows.

What to do if you return, and things don't feel right

In the days since the derailment in East Palestine, Ohio, authorities have lifted the evacuation orders and some people have returned. But residents are reporting symptoms they believe are tied to the chemical spill, according to Ideastream Public Media.

The outlet reported, "Jamie Cozza and her family evacuated to a hotel and have not moved back to town. She said she's glad she didn't return after a toxicology report done at her house came back with bad news. She said she had to demand further testing of her water and soil."

The authorities there maintain that the municipal water is safe to drink.

Sass, with the NRDC, said Cozza's instinct is the way to go: If your home is affected by a chemical spill, demand more testing on water and soil to be safe.

"Ask for more monitoring and then stay off using the water," she said.

In some of the affected areas of Ohio where residents rely on private wells and other private sources, authorities encouraged people to only drink bottled water.

But Sass recommends going even further: "Don't shower with the water" and don't boil it either. If hazardous chemicals are involved, heating water can actually make certain chemicals more volatile and can make them easily inhalable.

"So the hotter the water is, the more it's going to volatilize into the air," she said. Even cooking with potentially contaminated water is a huge no-no as the water will eventually turn to steam and can have a toxic effect.

And finally, listen to your gut and your nose

Ideastream also reported that the Ohio community is struggling with the lingering smells of the spill.

The outlet spoke to Candice Desanzo, who evacuated the area with her children but returned after the evacuation order was lifted. She's regretting that decision.

"We all have red rashes, loose stool, very congested, eyes burning, everything smells," Desanzo told Ideastream. "I've been having terrible headaches."

Brown, with Cornell University, said the depth of the chemical exposure and health risks are unknown until authorities analyze the surrounding air.

While the EPA maintains that the air is safe and continues to do testing, "That doesn't mean [the smells] can't be nauseating or sickening, or be stressful because the reminders of the incident and the emotions" are tied to the smell, Brown said.

Stanford's Prunicki encourages those who may be affected to listen to their own mind and body and make decisions for their own personal safety.

"If smells are terrible, regardless if someone's saying it's fine, use your own your own judgment and err on the side of caution," she said. "If it is making me sick, I'm gonna get out of there."