What is Perchlorate?

Perchlorate is both a naturally occurring and manmade contaminant increasingly found in groundwater, surface water and soil. Most perchlorate manufactured in the U.S. is used as an ingredient in solid fuel for rockets and missiles. In addition, perchlorate-based chemicals are also used in the construction of highway safety flares, fireworks, pyrotechnics, explosives, common batteries, and automobile restraint systems. Perchlorate contamination has been reported in at least 20 states. Perchlorate greatly impacts human health by interfering with iodide uptake into the thyroid gland. In adults, the thyroid gland helps regulate the metabolism by releasing hormones, while in children, the thyroid helps in proper development. Perchlorate is becoming a serious threat to human health and water resources.

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What are DTSC's Perchlorate Best Management Practices (BMPs)?

In addition to overseeing the cleanup of sites contaminated with perchlorate, AB 826, the Perchlorate Contamination Prevention Act of 2003, required DTSC to adopt regulations specifying best management practices for perchlorate and perchlorate-containing substances. The Perchlorate Best Management Practices were adopted on December 31, 2005 and became operative on July 1, 2006.

  • Perchlorate Containing Material One-Time Notification
    By September 1, 2007, businesses that managed more than 500 lbs or 55 gallons of Perchlorate Containing Materials at their site must have submitted the notification.

If you are in the Department of Defense or you are in an industry centered on aerospace, fireworks, pyrotechnics, amusement parks, automobile air bag and safety restraint, lithium perchlorate batteries, or if you are in a public safety agency, the Perchlorate BMPs may apply to you. Others that may be affected by these regulations include farmers who use perchlorate-containing fertilizer, laboratories, bleach manufacturers and users, and Publicly Owned Treatment Works (POTWs). Even households may be affected. See the materials below for more information.

Perchlorate BMP Reference Documents


Perchlorate Prioritization Protocol

Cal/EPA and the Department of Defense (DoD) have finalized a procedure for prioritizing DoD facilities statewide that are contaminated with perchlorate. The protocol is designed to provide consistency between DoD and state officials on selecting sites that require perchlorate sampling. This agreement is the first of its kind in the country.


Fact Sheets and Other Information



 Contaminated Sites


 Analytical Methods


On-Line Resources