September 3-10, 2007

Ontario sets tougher standards for 14 air contaminants

Amendments to Ontario regulation 419/05 (Air Pollution-Local Air Quality) have set 19 new or updated air quality standards for 14 toxic contaminants, including one of the most stringent standards in North America for lead and lead compounds. With the latest amendments, the Ministry of Environment (MOE) has introduced an unprecedented 59 new or updated air standards in the past two years as part of the province's Plan for Cleaner Air to reduce industrial emissions.

New or more stringent standards will be phased in by February 1, 2013, except for lead where industry will be required to comply with new or tougher air standards by February 1, 2010. The MOE is helping facilities implement these changes by encouraging sector-wide technology benchmarking reports to promote industry to work together and move toward compliance with the regulations as efficiently as possible.

In addition to lead and lead compounds (for which a new point of impingement (POI) half-hour average standard of 1.5 micrograms per cubic metre (ug/m3) has been set), the amendments set new standards for chloroethane (16,800 ug/m3) and propylene (12,000 ug/m3), along with more stringent standards for: cadmium and cadmium compounds (0.075 ug/m3); chlorine dioxide (6 ug/m3); phosphoric acid (21 ug/m3); sulfuric acid (15 ug/m3); and hydrogen sulfide and mercaptans (part of the total reduced sulfur (TRS) group of compounds, each with a new limit of 10 ug/m3).

At the same time, guidelines for some substances have been upgraded to legally enforceable health-based standards. These include: ethylene oxide (0.6 ug/m3); n-butanol (2,760 u/gm3); 1,1-dichloroethane (495 ug/m3); isobutanol (13,800 ug/m3); methyl chloride (960 ug/m3); TRS (10 ug/m3); and the 1,2,4 isomer of trimethylbenzene (TMB, 660 ug/m3). The Ministry has deferred a final decision on the standard for toluene pending further consultation with stakeholders on how to consider secondary health effects, such as smog, in the standard-setting process.

The amendments to the regulation also include measures to improve the implementation of requirements to protect local air quality and provide greater protection of public health and the environment. For example, regional meteorological data and regulatory air dispersion models have been updated, as have opacity requirements. As a result of the revisions, locations where human activities regularly take place will be considered in assessing compliance with odour-based standards (measurement only). Finally, administrative amendments have been incorporated to ensure clarity for compliance and enforcement purposes.

The amendments to O Reg 419/05 have resulted in changes to other regulations, notably revocation of O Reg 337 on ambient air quality criteria (AAQC, after one year), which contains unenforceable AAQC. The MOE intends to publish an AAQC list to replace O Reg 337.

The Ministry consulted extensively with industry, health groups and environmental groups on these new or updated air standards based on improved scientific information and updated research on associated health risks. The standards for these substances will be used primarily to assess and manage local impacts from industries on surrounding neighbourhoods and communities.

The Air Pollution-Local Air Quality regulation represents a new approach to setting standards for air quality that focuses on health and environmental effects rather than consideration of technical or economic barriers. Under this approach, substances were chosen for updating based on their toxicity and the quantities being released in Ontario.

Commenting on the regulatory initiative, Don Campbell, vice-president and resident manager for Bowater's Thunder Bay pulp and paper operation, said, "The ministry's transparent public consultation played a key role in Bowater's decision-making process, leading to the investment of over $150 million dollars in environmental improvement programs. As a result of the investment, Bowater-Thunder Bay has seen significant reductions in air emissions and has also provided for future regulatory requirements."

The final decision on the regulation has been posted on the Environmental Registry,, reference No RA06E0005.

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