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Toxics Release Inventory (TRI) Program

Methyl Isobutyl Ketone Petition

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Rule Summary

EPA has denied a petition to remove methyl isobutyl ketone (MIBK) from the list of chemicals subject to the reporting requirements under Section 313 of the Emergency Planning and Community Right-to-Know Act (EPCRA) and Section 6607 of the Pollution Prevention Act (PPA).

EPA’s review of the petition and available information resulted in the conclusion that MIBK meets the listing criteria of EPCRA Section 313(d)(2)(B) due to its contribution to the formation of ozone in the environment which causes adverse human health and environmental effects.

Rule History

On April 23, 1997, EPA received a petition from the Ketones Panel of the Chemical Manufacturers Association (CMA) to delete MIBK from the list of chemicals reportable under EPCRA Section 313 and PPA Section 6607. CMA had submitted petitions to delete methyl ethyl ketone (MEK) and MIBK from the EPCRA Section 313 reporting requirements in September 1988, but these petitions were subsequently withdrawn because the petitioner became aware of the Agency’s concerns for various toxicological effects of these chemicals.

The petitioners asserted that MIBK is not known to cause, nor can it reasonably be anticipated to cause, significant adverse acute health effects at exposure levels that are likely to occur beyond industrial site boundaries as a result of continuous or frequently recurring releases. They also stated that MIBK is not known to cause and cannot reasonably be anticipated to cause, significant chronic health effects in humans. The petitioners argued that MIBK also does not cause the type of adverse environmental effects that warrant reporting under EPCRA Section 313.

EPA denied this petition based on the conclusion that Volatile Organiz Compounds (VOCs), such as MIBK, contribute to the formation of tropospheric ozone which is known to cause significant adverse effects to human health and the environment. Therefore, EPA concluded that MIBK meets the listing criteria of EPCRA Section 313(d)(2)(B) and (d)(2)(C).

Additional Resources

Denial of Petition (PDF)(6 pp, 176 K, About PDF)