Exploring applications of the Ontario Toxics Reduction Act (TRA) for exposure surveillance

Exposure to toxic substances in the workplace contributes significantly to the global disease burden and is increasingly recognized as an important disease risk factor. In Ontario, the reduction of workplace exposure to toxic substances, including cancer-causing agents, could help prevent many occupational diseases in the province. An effective exposure surveillance system can serve as a tool to inform workers of potential hazardous substances they may be exposed to in their workplace and also aid policy makers in setting priorities for occupational exposure monitoring and enforcement activities.

Data from exposure surveillance databases can be used to establish priorities for disease prevention related to particular types of toxic substances, or in particular industrial sectors or regions where these substances are used. Fortunately, a legislated database that collects annual data on the industrial use of various toxic chemicals already exists in the Province of Ontario. The Toxics Reduction Act (TRA), Ontario Regulation 455/09, requires industrial facilities in four major manufacturing and mineral processing sectors to track and report their use and emission of toxic substances to the Ontario Ministry of Environment and Climate Change. The TRA is the only program of its kind in Canada and provides a unique opportunity to leverage this type of data for an exposure surveillance system in occupational health.

The OCRC produced a report describing the potential application of the TRA Program as an exposure surveillance tool by examining current trends in toxic substance use by industry sector, geographic region and substance type. Our findings identified geographic regions in Ontario where the use of cancer-causing substances was highest, such as in Lambton County and the City of Sudbury. We also used TRA data to identify particular sectors, such as the chemical manufacturing and the primary metal manufacturing sectors, which would benefit from an exposure surveillance system. Our findings suggest that targeted toxic substance use reductions in key sectors and regions could minimize potential occupational exposures among workers to lower overall occupational disease risk. The full report, as well as the key findings, are presented below.


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Exploring applications of the Ontario Toxics Reduction Act for exposure surveillance

Catherine E. Slavik, Sheila Kalenge, Paul A. Demers

May 2018


Location of TRA Facilities in Ontario

Carcinogen Use by Industrial Sector

Total estimated use* of carcinogens and top carcinogens† used by industrial sector, ranked by use in tonnes, TRA Program 2011-2015.

Sectors using carcinogens Mean employees Total estimated use (tonnes) Top carcinogens used
Chemical manufacturing 12,819 10,468,540 Benzene; Vinyl chloride; 1,3-Butadiene
Primary metal manufacturing 132,401 4,749,630 Nickel; Benzene; Lead
Petroleum and coal products manufacturing 14,891 1,977,480 Benzene; 1,3-Butadiene; Nickel
Mining (except oil and gas) 28,461 658,310 Nickel; Lead; Arsenic
Transportation equipment manufacturing 42,223 205,020 Nickel; Hexavalent chromium; Lead
Paper manufacturing 18,307 28,530 Formaldehyde; Lead; Arsenic
Fabricated metal product manufacturing 10,676 25,140 Nickel; Hexavalent chromium; Lead
Wood product manufacturing 4,102 9,770 Formaldehyde; Arsenic; Benzene
Machinery manufacturing 1,523 7,650 Nickel; Lead
Plastics and rubber products manufacturing 3,891 6,370 Lead; Hexavalent chromium; 1,3-Butadiene

* Values for estimates of use were rounded to the nearest 10th.
† Top carcinogens used represent the three carcinogens reportedly used in the largest quantities, listed in decreasing order.