Acrylonitrile and the Toxics Release Inventory (TRI)
The Toxics Release Inventory (TRI) is an annual survey that the U.S. EPA conducts on the release and disposal of chemicals. Acrylonitrile (AN) is one of the many substances listed on the TRI list and both manufacturers and users of AN must report TRI information to U.S. EPA.
Not every pound reported under TRI is the same. TRI captures pounds that are both released into the environmental and also sent to waste management. It’s important to understand this distinction when reviewing TRI information about a chemical or facility. Air is the environmental media of greatest interest for AN. Under TRI there has been a significant (92%) reduction in AN air emissions over the last 20+ years (1988-2009).
AN was among the initial substances that EPA placed on the TRI list when it was first established in 1987. AN has been reported under TRI every year since then (most assessments of TRI data start with reporting year 1988 as the data from 1987 was not deemed to be reliable). The Toxics Release Inventory (TRI) is an annual survey that the U.S. EPA conducts on the release/disposal of chemicals. EPA states that:
The goal of the Toxics Release Inventory program is to provide communities with information about toxic chemical releases and waste management activities and to support informed decision making at all levels by industry, government, non-governmental organizations, and the public.
The total amount of a chemical reported under TRI is not the same as the amount released to the environment. A portion of the total amount of pounds reported under TRI include direct releases to the environment such as air and water emissions while some pounds come from material sent to waste disposal/containment systems such as regulated underground injection wells and disposal facilities. The AN Group looks primarily at the releases of AN to environmental media such as air and water, where the potential for exposure to the public might exist, as opposed to AN disposed of in underground injection wells where the potential for exposure is essentially zero.
A recent review by AN air emissions reported under TRI by the AN Group has shown a significant reduction in air releases over the past 20 years. In 2009,the total air emissions of AN reported under TRI (for all facilities) was 373,748 lbs., which is down from 4,796,161 lbs. of air emissions in 1988 – a reduction of over 92%! This drop in air emissions is due to the ongoing improvements in facility operations and technology that manufacturers and users of AN have implemented over the last 2 decades.