Results show that approximately 9,300 Canadians are potentially exposed to acrylamide at work; 90% of these workers are male. The largest industrial group exposed is foundation, structure, and building exterior contractors where acrylamide is used in cement and concrete to slow the dehydration process and improve structural strength, as well as for water-proofing.
When exposure is examined by occupation, the largest exposed groups are concrete finishers (2,000 workers), construction trade helpers and labourers (1,900) and labourers in mineral and metal processing (1,000).
Data Sources & Methods
Data used in developing the occupational estimates for acrylamide were collected from several sources:
- The Canadian Workplace Exposure Database (CWED) contains less than 50 measurements for acrylamide exposure. These measurements were collected during the years 1991 to 1995 in Ontario workplaces.
- Canadian and US scientific peer reviewed publications that addressed acrylamide exposure in Canada and the United States.
- Grey literature including technical reports from governments and international bodies.
Prevalence Estimate Method
CAREX defines exposure to acrylamide as inhalation exposure at work to acrylamide or polyacrylamide (containing acrylamide monomer) likely exceeding non-occupational exposure (i.e. from food sources).
To determine the number of workers potentially exposed to acrylamide at work, CAREX occupational exposure experts used methods previously established in other peer-reviewed CAREX projects in Europe. A series of steps were taken to assign exposure proportions to occupations and industries at risk of exposure to acrylamide.
- Occupations and industries at risk of possible exposure to acrylamide were identified using any combination of data sources described above.
- The total number of workers in each identified occupation and industry intersection was obtained from Statistics Canada 2006 census data.
- A percentage of workers exposed was assigned to that occupation and industry intersection. Percentages were determined by consultation with existing evidence in the data sources, previously established methods from the Europe CAREX estimates and the expert judgement of CAREX occupational hygienists.
- The number of workers in the identified group is multiplied by the assigned percentage to calculate the prevalence estimate of workers exposed to acrylamide.