The U.S. Environmental Protection Agency announced on March 31 that it completed review of a July 2020 determination to not regulate perchlorate in drinking water. The agency concluded the 2020 decision is supported by the best available peer-reviewed science.
Additionally, the EPA announced multiple integrated actions designed to protect the public from perchlorate in drinking water.
“(The) EPA is taking action and applying the right tools to support public health protections,” said EPA Assistant Administrator for Water Radhika Fox. “Funding through the Bipartisan Infrastructure Law, a new monitoring study, financial and technical tools, and cleanup of contaminated sites will enhance protections and help ensure that communities can rely on clean and safe drinking water.”
Through the Bipartisan Infrastructure Law, the EPA is providing $11.7 billion through the Drinking Water State Revolving Funds supplemental, and $4 billion in dedicated funding to address emerging contaminants. This funding is part of the single-largest investment in U.S. water infrastructure and can be used to address perchlorate and other drinking water needs.
Investing in infrastructure will complement additional actions the agency announced on March 31. The EPA will support research to better understand perchlorate as it relates to firework displays and is planning to establish a web-based toolkit to provide updated technical information to drinking water systems and communities that may have concerns about perchlorate contamination. The toolkit is expected to be available online in 2022.
Perchlorate is commonly used in solid rocket propellants, munitions, fireworks, and airbag initiators for vehicles, matches, and signal flares. Perchlorate may occur naturally, particularly in arid regions such as the southwestern United States and can be found as a byproduct in hypochlorite solutions used for treating drinking water and nitrate salts used to produce fertilizers, explosives, and other products.
While the EPA is not pursuing a drinking water regulation at this time, the agency is going to continue to consider if perchlorate should be added to future Contaminant Candidate Lists for possible regulation under the Safe Drinking Water Act.
The EPA’s decision does not impact any state standards for perchlorate.
NGWA has a best suggested practice for treating perchlorate in residential well systems. In it, the BSP states “Ingestion of perchlorate affects iodine uptake by the human thyroid and thus thyroidal hormone production,” while adding “public health risk from perchlorate remains controversial.” It has also been reported perchlorate causes cognitive and physical damage to children.