Benzene Pollutes Air After Houston-Area Petrochemical Storage Fire
Houston County officials ordered a shelter-in-place for residents in Deer Park, Texas, a Houston-suburb, in mid-March for fear of dangerously high benzene levels. The order came after officials identified benzene vapors coming from a chemical storage fire at the Intercontinental Terminals Company (ITC). Benzene levels in the area quickly crossed the threshold for air quality standards.
The order advised residents to remain indoors, close all doors, windows and other sources of outside air. Additionally, officials recommended turning off air conditions and heating systems as well as close fireplace dampers to keep chemical vapors from entering their homes.
Benzene in the air can lead to a variety of problems. For example, the Centers for Disease Control and Prevention says that long-term exposure to high levels of benzene can cause leukemia .
In the News: Benzene Air Pollutant After Houston-area Chemical Storage Fire
A large chemical storage fire broke out at Intercontinental Terminal Company, a storage facility in Deer Park, Texas, on March 17, 2019. Reports say that the fire started in a single tank and quickly spread to a second tank. The original tank contained a volatile gasoline component called naphtha. By March 18, the fire affected six tanks.
The fire led to a plume of smoke that covered much of the Houston suburb. A company report filed with state environmental regulators says that a manifold leak is the cause of the massive fire.
The fire released over 9 million pounds of pollutants into the air before being extinguished on March 20. Additionally, an alarming amount of benzene was released in the form of vapor once the fire was extinguished. Further, a March 21 reading detected benzene levels at 190.68 parts per billion. This number exceeds the Texas Commission on Environmental Quality limits of 180 parts per billion.
What is benzene?
Benzene is among the 20 most used chemicals in the United States. It is a colorless liquid with a sweet smell. The highly flammable chemical finds its use in cutting grease and dissolving rust. Most human exposure occurs through working with the chemical in maintenance, home repairs and commercial and industrial environments. Benzene also occurs naturally in volcanoes and forest fires.
Everyday products that contain benzene include the following:
- Motor fuels
- Nylon and synthetic fibers
Benzene also occurs in naturally crude oil, gasoline and vehicle exhaust. For this reason, workers in the oil industry and those who live near chemical storage facilities are at an increased risk of inhaling benzene.
How does benzene get into the air?
While benzene is a liquid, when it is exposed to room temperature air, it evaporates quickly. Outdoor air typically contains low levels of benzene from tobacco smoke, gas stations, vehicle exhaust and industrial emissions.
Typically, in larger cities, there is more benzene in the air because of the amount of vehicle exhaust. This is especially true in industrial large cities like the Houston area.
Indoor benzene exposure
For indoor air exposure, the exchange of air between indoors and out means that indoor levels can be just as a high as outdoors. In some cases, indoor air may be higher. For example, in homes with an attached garage housing fuel products, benzene levels may be significantly higher than those who don’t store fuel products. Other examples include homes that use a kerosene heater for heat or a gas stove for cooking.
However, the biggest source of indoor exposure is through tobacco smoke. Homes of non-smokers average benzene levels of about 2.2 parts per billion while homes of smokers have an average of 3.3 parts per billion. The benzene levels in bars that allow smoking have been measured between 8 and 13 parts per billion. In short, people who smoke absorb 10 times more benzene in a day than non-smokers.
Other ways benzene exposure occurs
Air isn’t the only way people are exposed to benzene. Human exposure to benzene also occurs in the following ways:
Direct contact. Benzene exposure may occur through direct contact with the liquid if it is spilled on the skin. Benzene can penetrate the skin and be absorbed into the body.
Water. Wells and other water sources can become contaminated with benzene as a result of gasoline spills. In water, benzene remains very volatile and will quickly find its way into the air. Many people are exposed to benzene in the shower. The hotter the water, the more benzene will evaporate into the air.
Food. Small amounts of benzene can be found in fruits, vegetables, meats and some dairy products.
Preventing Chemical Storage Fires
Preventing chemical storage fires starts with ensuring chemicals are properly stored. Internal floating roof storage tanks are the recommended standard for the bulk storage of benzene. Tank designs should eliminate fugitive emissions. Further, tanks used for storage be designed to meet local regulations. While heating pads and internal coils should be used to maintain benzene at the proper storage temperature, tanks should be maintained to prevent exposure to these heat sources.
Tanks that contain benzene should be stored in an area that is:
- Out of direct sunlight
- Away from heat and ignition sources
- Separate from incompatible materials
- Fire resistant
- Away from combustible and flammable maters (such as cardboard and old rags)
What are the health effects of benzene polluted air?
When you are exposed to benzene through the air, half of the benzene you breathe in passes through the lining of your lungs and enters your bloodstream.
Communities that surround chemical facilities already face some of the highest cancer risks. In particular, Houston suburbs such as Deer Park, Manchester, Harrisburg, Meadowbrook and Allendale face some of the highest cancer risks in the Houston area from ethylene oxide emission from the ITC facility.
According to reports, roughly 1,000 people sought treatment at a pop-up treatment center after the Intercontinental Terminal Company fire that burned for three days. At least 15 of those cases were serious enough for transfer to local emergency rooms.
- Respiratory problems
Since 2003, ITC has received 35 reports of emitting toxic air contaminants.
Long-term benzene exposure and cancer
Benzene is a known carcinogen. This fact is based on evidence from studies in human and lab animals. Most often, the chemical is linked to leukemia, particularly acute myeloid leukemia (AML) and other cancers of blood cells.
Studies also suggest a link between benzene and the following blood cancers:
- Childhood leukemia
- Acute lymphocytic leukemia (ALL)
- Chronic lymphocytic leukemia (CLL)
- Multiple myeloma
- Non-Hodgkin lymphoma
How long does benzene stay in your system?
Most of the metabolites of benzene leave the body through the urine within 48 hours after exposure.
There are currently no medical tests to determine levels of benzene after long-term exposure. However, for acute exposure to very high levels of resulting metabolites may be detected by testing your breath. This test is not very helpful in detecting very low levels of benzene in the body. Benzene monitoring for people who work with the chemical may occur through urine testing.
Most of us can’t help where we live. In many cases, we are tied to our communities through work, our children in school or living close to family. For this reason, companies have a responsibility to prevent chemical storage fires that can lead to harmful exposure. Benzene exposure injuries can affect your family when its just one family member exposed through work. However, the Deer Park fire raises the stake tremendously and exposed entire families to the toxic chemical.
Still, this company has not taken the appropriate measures to avoid putting locals in the area at risk.