Dioxins and Furans
Dioxins are carcinogens that come from combustion, incineration, metal production, or other industrial processes that involve chlorine. Dioxin contamination can last for decades because the chemical breaks down very slowly in the environment. The EPA estimates that dioxin emissions decreased 11% between 2013 and 2022 and the toxicity equivalents decreased by 24% during that time. Many of these chemicals are confirmed carcinogens and reproductive toxicants and can be extremely dangerous to worker’s during the manufacturing process. These chemicals can also be found in very small amounts in certain herbicides, and wood preservatives.
In 1987, EPA worked with states to reduce environmental leaks and releases of dioxins and furans to land, air, and waterbodies from US sources, resulting in an 85% decline in total releases from known industrial processes. However, these regulatory actions, including the Superfund and the Resource Conservation and Recovery Act Corrective Action (RCRA) programs, have not ultimately eliminated these chemicals from our environment today. As a result, communities around the country are still being impacted by these legacy chemicals.
TCE + 1,4-Dioxane: Environmental Legacy Chemicals Persist
Historically, trichloroethylene, also known as TCE, was used as an industrial degreaser. It was commonly used on air force bases and in many manufacturing settings. In Tucson, Arizona, TCE, along with 1,4-dioxane and several other hazardous chemicals, was routinely dumped in areas of South Tucson and in the Tucson International Airport Area during the 1950s. In the early 1980’s, EPA tested water wells on the south side of Tucson and found TCE levels significantly exceeding EPA’s limits and as a result, was added to the Superfund site national priority list.
It took until 1994 for the Tucson Area Remediation Project (TARP), a treatment plant for contaminated water, to begin full operation. To this day, the TCE plume is still present in Tucson’s aquifer system and is actively being cleaned up by a consortium of government agencies with the participation of various community groups. However, communities are still concerned about this environmental injustice that plagues many families still.
Resources:
- EPA Updates: the Tucson International Airport Area Superfund site
- EPA: Dioxin Overview
- EPA: Dioxin at Superfund Sites
- OSHA: Trichloroethylene (TCE) - Occupational Chemical Database
- NIOSH: Pocket Guide to Chemical Hazards