PBTs – What’s All the Buzz About?
There has been significant new emphasis on a class of old problems – Persistent, Bioaccumulative and Toxic chemicals, or PBTs. These include such infamous substances as PCBs, dioxins and furans; heavy metals such as lead, mercury, and chromium; existing and banned pesticides; and other chemicals with PBT characteristics. PBT pollutants pose risks because they are toxic even in small quantities, persist in ecosystems, bioaccumulate in food chains, and can travel great distances (e.g., in air or water, or in foodstuffs, equipment or products). While much progress has been made to reduce loadings, PBTs continue to threaten human and ecosystem health. And since PBT pollutants transfer rather easily among air, water, and land, and span boundaries of programs, geography, and generations, environmental agencies increasingly recognize that they need to go beyond single-media control approaches.
The threat is widely recognized. The International Joint Commission of Great Lakes Water Quality has declared that persistent toxic substances are too dangerous to the biosphere and to humans to permit their release in any quantity. There also are international efforts to eliminated persistent organic pollutants. The environmental legacy of PBTs are clear as well:
- 39 states have issued mercury advisories for more than 50,000 water bodies nationally.
- Hundreds of waterbodies in Region 9 are listed as impaired due to mercury, dioxin, PCBs, and other PBT chemicals.
- California and Arizona have to establish TMDLs (Total Maximum Daily Loads) for numerous waterbodies due to PBT contamination, including the Sacramento River and the San Francisco Bay and Delta. This may require industries, POTWs, stormwater agencies to reduce PBT loadings.
- Region 9 industries released more than 3.5 million pounds of potential PBT chemicals, according to 1996 TRI data (which only captures the largest industrial operations).
The USEPA has developed a draft national strategy to address priority PBT pollutants. The goal of this Agencywide, multimedia strategy is to identify and reduce risks to human health and the environment from existing and future exposure to priority PBT pollutants. Under the Strategy, the Agency will develop Action Plans for Priority PBT Pollutants which will employ EPA’s full range of tools (international, voluntary, regulatory, programmatic, compliance, enforcement, research) to prevent and reduce releases of these pollutants. EPA has released a draft action plan for mercury as a model, and will release the final strategy by the end of 1999. Many state and local government agencies and nonprofits across the country also are working to reduce releases of, and exposure to, PBTs. For example, they are conducting projects focused on reducing PBT waste in industries such as hospitals, chlor-alkali facilities, and metal finishing; investigating PBT sources in their communities; and educating the general public about their role in reducing PBT risks.
While tracking national developments, EPA Region 9 also is working to identify regional PBT priority chemicals and sources, and to better coordinate on regional PBT issues. The Region 9 Pollution Prevention Team hopes to work with state, local, and non-profit pollution prevention providers to identify priority PBT pollutants and sources for targeted source reduction efforts. We hope to support this work with national and regional funds and regional staff time.