BALTIMORE (WJZ) — More than a day after a chemical spill at a Curtis Bay plant, people living near the site of Monday’s acid spill say they’re still concerned about what they could be breathing in, even after a shelter in place was lifted.

Nearby residents say they saw the vapor cloud that came after the spill.

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Many of them were outside at the time, but had no idea what was happening until they received a text on their phone more than an hour later.

Baltimore City Fire Department investigators are leading the way into finding out what caused an acid spill at the Solvay plant in Curtis Bay Monday morning.

“Apparently, what happened here, they were doing a transfer of a chlorosulfonic acid from a tanker to a trailer,“ Baltimore City Fire Chief Roman Clark said following the spill.

The spill created a vapor cloud in the sky, forcing people within a mile to shelter in place.

According to the Environmental Protection Agency, more than 18,000 homes are within three miles of the plant.

“A friend of mine came outside and said, “Ang, what are you doing? You can’t be outside right now,’” Angela Snyder, who lives nearby, said.

Snyder says she was outside and saw the cloud.

“Right as he said that, I got an alert through my phone, like a sound,” Snyder said.

Even with an all clear given two hours later, Snyder, like many others, says she’s still concerned about what the toxic and corrosive chemical could do to their health.

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“I’m very concerned. I’m still very concerned,” she said.

Chlorosulfonic acid is used in a number of products, like sweeteners, detergents, and soaps.

The company isn’t saying how much of the chemical actually spilled.

Searching through EPA records, WJZ found the company violated part of the Resource Conservation and Recovery Act during a 2015 inspection.

The law defines the proper use of hazardous and non-hazardous waste.

People living in the area are hoping that a repeat of Monday doesn’t happen.

“You need to take more extreme caution to make sure things like this don’t happen,” Snyder said.

The company says they are now investigating the incident.

Click here for Solvay’s complete inspection history from the EPA.

The Maryland Department of Environment has asked the company for an incident report, and plans to send an inspector to the plant.

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