A petition dating from 2002 requesting that the EPA delete acetonitrile from the list of chemicals that must be reported under the toxics release inventory (TRI, Section 313 of the Emergency Planning and Community Right-to-Know Act (EPCRA)) has been denied by the Agency.  According to the EPA, acetonitrile can reasonably be anticipated to cause serious or irreversible chronic health effects in humans, one of several criteria for requiring that a chemical be reported under Section 313.

Acetonitrile is produced by refining crude acetonitrile, a by-product of acrylonitrile.  The demand for acetonitrile has been growing in recent years.  The chemical’s primary applications are as a solvent in the manufacture of butadiene, pharmaceuticals, and photographic film.  In 2012, Asahi Kasei Chemicals announced plans to construct a new acetonitrile plant in Korea.

Petition to delist

Under EPCRA Section 313, facilities that manufacture, process, or otherwise use listed toxic chemicals in amounts above reporting thresholds must report releases of those chemicals to the environment.  Congress wrote EPCRA with an original list of Section 313 chemicals, which included acetonitrile.

In addition, the statute contains provisions to either add chemicals to the list or delete them.  There are three types of listing criteria:

1. The acute human health effects criterion
2. The chronic human health effects criterion, and
3. The environmental effects criterion.

A chemical can be listed if it meets any of those criteria.  To be delisted, it must be demonstrated that the chemical meets none of the criteria.

Chronic mortality

The 2002 petition from BP Chemicals, Inc., was in fact preceded by a 1998 petition from the same company, which sought delisting of acetonitrile.  That petition was denied by the Agency.  In 2002, BP Chemicals Inc., again petitioned for a delisting, this time arguing that acetonitrile meets all the criteria for a TRI delisting because (1) under generally accepted scientific principles, chronic mortality is not an issue for concern; and (2) EPA’s Office of Air Quality Planning and Standards concluded that acetonitrile does not have sufficient photochemical reactivity to contribute to ozone formation.  The BP group that submitted the petition was subsequently acquired by INEOS USA, LLC, which took over the petition. 

In a 2008 letter to the EPA, the Acrylonitrile (AN) Group stated that EPA’s reasoning that acetonitrile has chronic health effects—i.e., mortality—was not supported by a too short–13-week study–on laboratory animals.  In contrast, the AN Group pointed to several “valid” 2-year studies that did not show any mortality. 

In the more recent denial, the EPA sticks to its belief that the 13-week study presents sufficient evidence that chronic exposure to acetonitrile can be reasonably anticipated to cause serious or irreversible chronic health effects in humans.

Given that the EPA believes that acetonitrile meets the chronic human health effects criterion, the Agency review did not consider acetonitrile’s status as a volatile organic compound (VOC) and thus, its contribution to the formation of ozone in the environment. 

Denial of the petition to delist acetonitrile was published in the March 5, 2013, FR.