DEER PARK,Texas–In March 2019, a large chemical fire caused toxic smoke to spread over a Houston suburb. A week after the fire was put out, Mario Ochoa held his 4-year-old son, Castiel, and prayed that the child’s cough would ease so that they could both sleep.
However, Castiel kept waking up with frightening snoring that sounded like he was struggling to breathe. Ochoa described the experience as watching his son “drown right in front of” him.
A group of massive tanks, some containing millions of gallons of highly flammable chemicals used to make plastic and gasoline, had caught fire at a chemical storage facility owned by Intercontinental Terminals Company, a Texas-based company owned by Japanese conglomerate Mitsui Group. The fire began after a tank’s pump failed and began to leak naphtha, a highly flammable liquid.
As the fire at ITC spread from tank to tank, an ominous black plume of smoke spiraled over the Houston skyline. Ten of the tanks — each big enough to hold more than 3 million gallons of chemicals — collapsed, sending chemicals gushing into the nearby ship channel and killing birds and fish. Ash rained down on nearby neighborhoods.
Twice, city officials advised residents of Deer Park, the city closest to the fire, to shelter indoors. The first lasted 18 hours immediately after the fire broke out, and the second came three days later when air monitoring detected extremely high levels of benzene — an invisible, sweet-smelling hydrocarbon often found in crude oil and cigarettes.
It’s known to cause cancer after repeated exposure and can irritate the throat and eyes. When inhaled in large quantities over a short period, benzene can affect the central nervous system and cause symptoms including dizziness, a rapid heart rate and headaches.
But what Ochoa and other residents weren’t told by federal, state and local officials at the time was that long after the fire was extinguished and life seemed to go back to normal, an invisible danger remained.
Benzene emissions spiked to abnormally high and potentially dangerous levels for more than two weeks after nearby residents were told it was safe to return to school and work, according to a Texas Tribune analysis of U.S. Environmental Protection Agency air-monitoring data. The data was collected by a mobile laboratory that roamed the area for two months after the fire erupted — one of many air quality devices deployed to monitor pollution at the time.
Almost 1,000 people swarmed to temporary mobile health clinics in Deer Park that operated for three days after the fire started, and Texas Poison Center Network records show its hotline received almost 200 calls reporting chemical exposure from the ITC fire over a more than two-week period. The most frequent symptoms were headache, throat irritation, nausea, coughing, dizziness and vomiting.
The fire had been out for days when Ochoa, a 39-year-old pipe fitter at an industrial construction company, sat awake late into the night worrying about his son, who complained that his head hurt. Ochoa grabbed a few pillows and tucked himself in a corner, hugging his son tight. He felt helpless. “I was watching him and knowing, he doesn’t even realize he’s suffocating,” he said.
He took his son to the hospital the next morning.
A few days into the crisis, officials from the EPA, the Texas Commission on Environmental Quality and Deer Park had to make a crucial decision: How much benzene in the air is too much for people to breathe? They decided they would issue public warnings only when benzene levels reached 1,000 parts per billion in the air over one minute — a level that scientists who study benzene now say was too high.
The federal, state and local officials who formed a “Unified Command” near the ITC facility after the fire erupted had to choose a threshold on the spot because there’s no accepted national standard for how much benzene in the air should be considered dangerous. They adapted it from the federal workplace standard, which allows worker exposure up to 1,000 parts per billion over an 8-hour work day.
Anita Desikan, one of the authors of a December 2022 study of the ITC fire and a senior analyst for the Center for Science and Democracy at the Union of Concerned Scientists, said the action level used during the ITC incident was “out of line with basically every other measure I’ve seen [for] benzene.”
“It’s concerning that would be the case for an emergency situation,” she said, adding that “you will see people hurt and harmed if it’s your only number for taking action.”
At a March 26 press conference — nine days after the fire started — an EPA official said the agency would “get it out to the community to take action” if it detected benzene levels above that level. “So you can trust that if it’s 1,000 parts per billion … we will let you know.”
But those warnings didn’t always come. Or, they came too late for residents to take action.
The EPA data that the Tribune used for its analysis, which was originally obtained by the nonprofit Environmental Defense Fund, shows that benzene spiked above 1,000 parts per billion on at least seven different days after the second and last shelter-in-place advisory expired — although it’s unclear from the data whether those spikes lasted for an average of 1 minute.
On six of those days, the spikes occurred in industrial areas near the ITC facility, but on March 31 — a full two weeks after the fire began — benzene spikes above 1,000 parts per billion were recorded in a residential area of Deer Park. Data from TCEQ’s stationary and handheld monitors also indicated elevated benzene concentrations near the same times and locations as the EPA’s mobile lab.
The benzene drifting through Deer Park “was a health threat to the community that went basically unshared,” said Elena Craft, a senior scientist at the Environmental Defense Fund.
“I don’t think anyone really understood the magnitude,” Craft said. “Or, they still don’t.”
When a reporter asked Deer Park Mayor Jerry Mouton about the strong smells that continued to waft through the city almost a week after the fire was extinguished, the mayor said those smells were “normal.”
“There are random times when we have smells,” said Mouton, who declined repeated requests for an interview. “We are monitoring the air continuously, and there’s nothing that’s even come close to registering any kind of action item.”
ITC said in a statement to the Tribune that there were “no longer-term public health impacts to the community” from the incident, pointing to an analysis by the Texas Department of State Health Services. The report found that health effects from benzene “were not expected to have occurred” due to the “short” amount of time high levels were detected.
The analysis did not take into account the fact that hundreds of people actually sought medical care during the incident.
Jennah Durant, a spokesperson for the EPA, said both the U.S. Centers for Disease Control and Prevention and the federal Agency for Toxic Substances and Disease Registry — a division of the U.S. Department of Health and Human Services — reviewed the action level “and had no objections.”
The city of Deer Park and ITC contracted with a company called CTEH to conduct hand-held air monitoring. In a written statement, Pablo Sanchez-Soria, a senior toxicologist at CTEH, said that using short time frames to measure benzene levels — in this case one minute in the community — help officials “take early action” to reduce human exposure.
“Based on our experience, the [1,000 parts per billion] action level for 1 minute for benzene across community areas was highly conservative,” Sanchez-Soria said. “Sufficiently protective values must be balanced against the inherent risk associated with actions such as evacuation.”
But Seth Shonkoff, an associate researcher of environmental health sciences at the University of California-Berkeley, said it’s “inappropriate to use occupational standards in a community setting” because they are designed for workers who are typically healthy adults trained to prevent chemical exposure with equipment such as respirators. Those workplace standards, he added, were a compromise between now-outdated benzene science and the economic impact on businesses.
Texas has guidelines that define what level of exposure to various chemicals could affect people’s health; for benzene, it’s 180 parts per billion in an hour. The state health agency used that number when it analyzed the potential for health problems from the ITC fire, but TCEQ spokesperson Victoria Cann said the number “does not constitute a bright line” for health impacts and is “precautionary in nature.” Emissions above that level don’t trigger any regulatory action by the agency.
A group of mostly Houston-area scientists using the most recent science on benzene exposure said that officials should have used a much more conservative threshold — 27 parts per billion in two consecutive hourly readings — and issued seven more shelter-in-place orders and 17 air quality alerts after the fire broke out. Their study, commissioned by the Houston Health Department, is awaiting peer review.
drian Garcia, a Harris County commissioner who represents Deer Park, said the county was “scrambling” to get current air quality data from the company or from federal and state agencies to inform their decisions.
“One of the things that I think the government tries hard to do is to be fair to everyone without being too quick to overly react,” Garcia said. “We were really trying to get to a place where we were being fair to the industry, but also transparent to the public about … whether there was still harm.”
“I’m not sure whether we really got there,” he said.
Four years later, Deer Park residents who fell ill — some of them children, elderly or otherwise at higher risk — said they sensed at the time that they were more exposed to chemicals than they were told. Many, like Ochoa, say they are still scarred by the experience.
“That kind of turmoil is haunting,” said Ochoa, who is now 43. “My soul remembers.”
