Consultation document on risk management measure for BNST: chapter 3

3. Industrial use of BNST

3.1 Current Uses

Based on the industry information provided during the Chemical Management Plan Challenge, the primary end-use application of BNST is as an antioxidant in vehicle engine oils. It also has a minor use as an antioxidant in commercial/industrial lubricants.

Information submitted as part of the Challenge indicates that fewer than five companies in Canada manufactured between 1 000 000 and 10 000 000 kg in 2006 and fewer than five companies imported between 100 001 and 1 000 000 kg for the same year.²

BNST is a High Production Volume (HPV) chemical under the HPV Challenge Program of the U.S. Environmental Protection Agency (US EPA). In the United States, according to the information collected by the US EPA, in the years 1990, 1994 and 2002, BNST was imported or used in quantities between 450 000 kg to 45 million kg per year (US EPA 2006). According to the Substances in Preparations in Nordic Countries database (SPIN 2006), this chemical was used in Sweden and Denmark in the years 1999-2004.²

3.2 Releases and Exposures Sources to the Environment

Approximately 98.3% of the BNST contained in engine oils and lubricants in Canada is either chemically transformed or combusted during use of engine and industrial oils or reprocessed into industrial fuels or base oils following collection of waste engine oil.

The remaining 1.7% is released to the environment through leaks and spills of lubricant that occur during commercial and consumer use, improper disposal of lubricant and from cleaning containers used to transport lubricant additives containing BNST:

• 1.5% released to sewer and soil, and
• 0.2% released to waste disposal sites.

The total environmental release is estimated to be around 7000 kg/year.

Minimal releases are expected from manufacturing and lubricant blending operations, as it is assumed that existing on-site wastewater treatments are highly efficient in removing BNST.