News Releases


Union Pacific Calls for Accuracy and Collaboration in Response to Dioxin Study

OMAHA, NEB., September 23, 2022

Union Pacific just received the results of the city of Houston’s dioxin study, after repeatedly asking for the data. The report shows the dioxin levels in the city’s samples are well below the Texas Commission on Environmental Quality’s clean-up standards for dioxins in residential areas.

Attributing widespread dioxin only to operations at the former Southern Pacific Houston Wood Preserving Works site is unreasonable and inaccurate. For more than a century, nearly 100 businesses operated in the highly industrialized area by the site. Now, the environmental remnants of the industrial prosperity that once flourished there are causing residents and regulators to raise concerns about pollutants on the ground, in the air and in the water.

According to the U.S. Environmental Protection Agency, dioxin-like compounds are found in soils everywhere due to a variety of sources. Jonathan Urban, PhD toxicologist with ToxStrategies, states that “Dioxins are primarily a byproduct of combustion and other industrial processes and it is not uncommon for them to be detected in urban and industrial areas. The important question is are they present at soil concentrations that might impact human health.”

Manufacturers, metal foundries, auto shops, electrical contractors, printing plants, laundromats and other businesses all operated in the area near the former Houston Wood Preserving Works site. In addition to dioxins, the chemical remnants these types of businesses may have left behind include arsenic, vinyl chloride, lead, Polycyclic Aromatic Hydrocarbons (PAHs) and Volatile Organic Compounds (VOCs), and dozens more.

Ensuring Site Safety for the Surrounding Community

Until the 1980s, Southern Pacific spent decades using creosote to treat wood for rail ties at its Houston Wood Preserving Works facility, affecting soils and groundwater. Union Pacific took responsibility for remediation activities when it merged with Southern Pacific – 13 years after the facility closed in 1984.

Over the past 25 years, Union Pacific conducted all cleanup activities under the oversight of state regulators. This includes removing creosote-impacted soil and constructing an engineered barrier cap consisting of clay and topsoil, concrete, asphalt and other materials. Additionally, Union Pacific removed a significant amount of creosote, both on and offsite. The railroad has met with city and county officials and local community advocates to discuss even more aggressive cleanup measures, containment and remediation activities.

Union Pacific’s Commitment to Houston

With 1,500 employees in Harris County, Houston is an essential hub for Union Pacific. In the last five years, the company has donated more than $2 million to over 100 nonprofits in the area. From hiring programs to local investments, Union Pacific is committed to leading with compassion, collaboration and, most importantly, action.

Union Pacific aims to work with the city of Houston, Harris County and the Bayou City Initiative to collect data and to formulate a sound, science-based plan for moving forward.

More details can be found at

About Union Pacific

Union Pacific (NYSE: UNP) delivers the goods families and businesses use every day with safe, reliable and efficient service. Operating in 23 western states, the company connects its customers and communities to the global economy. Trains are the most environmentally responsible way to move freight, helping Union Pacific protect future generations. More information about Union Pacific is available at

Union Pacific Media Contact: Robynn Tysver at 402-544-6037 or

The statements and information contained in the news releases provided by Union Pacific speak only as of the date issued. Such information by its nature may become outdated, and investors should not assume that the statements and information contained in Union Pacific's news releases remain current after the date issued. Union Pacific makes no commitment, and disclaims any duty, to update any of this information.