Occupational and Environmental Medical
Association of Canada
Niagra-on-the-Lake
October 4 th , 2011

• Percival Pott (1775) linked scrotal cancer in chimney sweeps to the nature of their work and their exposure to cancer causing agents in soot
• He was the first to identify an occupational carcinogen
• Finally in 1840’s laws were passed prohibiting young boys from performing the work

IARC

Group
1
2A
2B
3
4
Classification
Carcinogenic to Humans
Probably Carcinogenic
Possibly Carcinogenic
Unclassifiable
Probably Not Carcinogenic
Agents
107
59
267
508
1

• ~ 60 definite or probable workplace carcinogens (IARC 1 and 2A)
• Over 100 additional workplace exposures are possible carcinogens (IARC 2B)
• Many other workplace exposures with a suspicion of human carcinogenicity
• Even greater number of workplace substances with little formal evaluation

CAREX Canada Priority Occupational
Carcinogens (IARC Classification, cancers)
Industrial Chemicals
Aromatic amines (1, bladder )
1,3-Butadiene (1, lymphatic/hemaetopoietic)
TCDD (dioxins) (1, all cancers)
Benzene (1, leukemia, multiple myeloma, nonHodgkin’s lymphoma)
Formaldehyde (1, nasopharynx, leukemia, sinonasal?
)
Vinyl chloride monomer (1, liver)
Ethylene oxide (1, lymphoid?, breast?)
Polychlorinated Biphenyls (PCBs)(1/2A, ?)
Acrylamide (2A), Epichlorohydrin (2A)
6

CAREX Canada Priority Occupational
Carcinogens (IARC Classification, Cancers)
Metals
Arsenic & compounds (1, lung, bladder, kidney?, liver?, prostate?
)
Beryllium and compounds (1, lung)
Cadmium & compounds (1, lung, prostate?, kidney?
)
Chromium, hexavalent (1, lung, sinonasal?
)
Nickel & compounds (1, lung, sinonasal)
Lead & compounds (2A/2B), Antimony trioxide (2B), Cobalt (2A/2B)
7

CAREX Canada Priority Occupational
Carcinogens (IARC Classification, Cancers)
Dust and Fibres
Asbestos (1, lung, mesothelioma, larynx, ovary, pharynx?, colorectal?, stomach?
)
Erionite (1, mesothelioma)
Silica (1, lung)
Wood Dust (1, sinonasal, nasopharynx)
Leather Dust (1, sinonasal)
8

CAREX Canada Priority Occupational
Carcinogens (IARC Classification, cancers)
Radiation
Radon decay products (1, lung)
Plutonium (1, lung liver, bone)
X-radiation, gamma-radiation (1, lung, breast, leukemia, many others)
Solar radiation (1, skin squamous cell, basal cell, melanoma)
UV Tanning Devices (1, skin & eye melanoma)
Magnetic fields (ELF)(2B)
9

CAREX Canada Priority Occupational
Carcinogens (IARC Classification, cancers)
Combustion Products and Others
Polycyclic aromatic hydrocarbon related exposures (mix of 1/2A/2B, lung, skin, bladder)
Mineral oils (1, skin)
Diesel Exhaust (2A, lung?
)
Environmental Tobacco Smoke (1, lung)
Antineoplastic Agents (1/2A, leukemia, bladder)
Shiftwork at Night (2A, breast?
)
10

CAREX Canada Priority Occupational
Carcinogens (IARC Classification)
Chlorinated Solvents
Tetrachloroethylene (2A)
Trichloroethylene (2A)
1,2 – Dichloroethane (2B)
Dichloromethane (2B)
Chloroform (2B)
11

CAREX Canada Priority Occupational
Carcinogens (IARC Classification)
Pesticides
Chlorophenoxy Herbicides
(2,4-D, MCPA, MCPP)(2B)
Chlorothalonil (2B)
Dichlorvos (2B)
Lindane (2B)
Pentachlorophenol (2B)
Atrazine (3)
12

Author and Location
Nurminen et al
(2001)
Finland
Steenland et al
(2003)
United States
Male
Lung
Attributable Fraction (%) By Cancer Site and Gender
Leukemia Bladder
Skin
(NMSC)
Nasal Total
29
Female 5.3
18.5
2.5
14.2
0.7
13.1
3.8
24
6.7
13.8
2.2
Male
Female
8-19.2
2
0.8-2.8
0.8-2.8
5.6-19
5.6-19
1.2-6
-
31-43
-
3.3-7.3
0.8-1.0
Rushton et al
(2010)
United Kingdom
Alberta Health
Services, AHS
(2010), Alberta
Male
Female
Male
Female
21.1
5.3
6-33
1-5.5
0.9
0.5
1.8-18.5
0.5-3
7.1
1.9
1.2-27
0.4-19
7.1
1.1
1.2-13.1
3-3.8
46.0
20.1
24-64.3 3.3-13.8
2-18.4
8.2
2.3
0.1-2.2

CAREX Canada - OVERVIEW
•
The objectives of CAREX Canada are to:
– develop estimates of the number of Canadians exposed to IARC carcinogens in their workplace & community environments,
– identify how & where people are exposed, and
– when possible, determine their level of exposure.
•
Etimates are generated using existing Canadian exposure data, census population data & the best exposure estimation procedures available.
15

Potentially Exposed Workers: Initial Estimates
Known or suspected carcinogen (IARC) Exposed
Shift work with circadian disruption (2A)
Solar radiation (1)
Diesel engine exhaust (2A)
Silica (crystalline) (1)
Other PAHs (2A/2B)
Benzene (1)
Wood dust (1)
Lead (2A)
Ionizing radiation (1)
Asbestos (1)
UV radiation (artificial sources)(1)
Chromium (VI) compounds (1)
Nickel compounds (1)
Formaldehyde (1)
2,800,000
1,500,000
804,000
349,000
307,000
297,000
293,000
202,000
153,000
152,000
150,000
83,000
53,000
41,600

Industry sectors with potential over-exposure to carcinogens in Quebec: 2001-2005
Substance (IARC Category) Industries
PAHs (1/2A/2B) 70
Crystalline silica (1)
Wood Dust (1)
Beryllium (1)
27
25
12
Styrene (2B)
Methylene chloride (2B)
Lead (2B)
Nickel (1)
Cobalt (2B)
Asbestos (1)
11
11
9
7
4
4
* Institut de recherche RobertSauvé en santé et en sécurité du travail (IRSST) Rapport R-485, 2007

Canadian Workplace Exposure Database
(CWED)
18

Workplace Regulatory Agencies in Canada
19

Wood dust
Formaldehyde
Lead
Silica
Perchloroethylene
Benzene
Cadmium
Asbestos
Beryllium
Ontario (81-96)
3,848
7,936
7,806
4,666
2,764
1,441
1,358
1,787
292
BC (81-04)
7,194
2,788
3,060*
1,640
2,148
658
851
4,718
128
Quebec (01-05)
4,588
4,629
3,459
3,373
882
1,240
662
1,385
17,864
* plus 5,200 blood-lead & 17,400 urine-lead biological measurements

8
9
Mean benzene exposure over time in
BC and Ontario workplaces
4
3
2
1
7
6
5
0
80-84 85-89 90-94
* current ACGIH TLV is 0.5 ppm, NIOSH PEL is 0.1 ppm
95-02
BC
Ontario

7
6
5
4
3
2
1
0
1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996
Year

Levels of Exposure to Benzene by Industry
Sector, Ontario 1981-1996
Industry Sector (measurements) Mean ppm (range)
Gasoline stations (12) 13.0 (0.01-55.8)
Iron and Steel Mills (29)
Printing industry (38)
2.3 (0.01-16.0)
0.9 (0.01-7.8)
Pharm. & Medicine Mfr. (128)
Rubber Manufacture (192)
Plastics Manufacture (137)
0.7 (0.01-19.5)
0.1 (0.01-5.2)
0.05 (0.01-2.5)
Electrical Components Mfr. (21) 0.03 (0.01-0.2)

Benzene exposure to service station attendants: Personal long-term samples
Source
CPPI-PACE 1996
CPPI-PACE 1990
PACE Pilot 1987
Rappaport 1987
Halder 1986
Kearney 1986
Runion 1985
Weaver 1983
McDermott 1979
Location
Canada
Canada
Canada
USA
USA
USA
USA
USA
USA
Mean (ppm) n samples
0.04
78
0.38
0.03
0.2
0.3
0.1
0.06
0.06
0.09
280
42
49
21
18
1478
14
84
Compiled from Verma et al., 2001. ‘Benzene and Total Hydrocarbon Exposures in the
Downstream Petroleum Industries’, AIHAJ, 62:2, 176-194

Levels of Exposure to Crystalline Silica by
Industry Sector, Ontario 1983-1996
Industrial Sector (# samples) Mean* (range)
Construction (270)
Mineral products mfg. (1147)
Mining (277)
Basic metal industries (1465)
1.8 (0-52.0)
0.2 (0-27.0)
0.1 (0-2.7)
0.2 (0-22.5)
Metal products mfg. (577) 0.3 (0-66.5)
Other manufacturing (340) 0.2 (0-5.6)
Other industrial sectors (539) 0.2 (0-6.2)
* mg/m 3 , current ACGIH TLV is 0.05 mg/m 3

Number of People Exposed to Ionizing
Radiation by Industry in Ontario
Industrial group
Nuclear power
Medicine
Professional, scientific services
Uranium mining
Public administration
Other
Number monitored by
NDR (2005)
18,600
27,700
Number exposed*
7,320
4,280
6,950 2,570
18
2,500
13,000
2
475
2,900
*Exposure is defined as having an annual ionizing radiation dose of >0 mSv
26

Night, Evening & Rotating Workers in Ontario
Industries with the Highest Prevalence
27

28

Estimated Number of Farm Operators
Potentially Exposed to Chlorothalonil

Estimated Number of Farm Workers
Potentially Exposed to Chlorothalonil

Golf Course Pesticide Applicators by Province
Province/Region
BC
AB
SK
MB
ON
QC
NFL
PEI
NB
YT
NT
NU
Canada
84
174
6
3
0
7017
Total
1056
999
426
399
2493
1083
66
32

• Report of the Advisory Group to Recommend Priorities for IARC
Monographs during 2010–2014. IARC, Internal Report 08/001. Lyon,
France, 2008
• Ward EM, Schulte PA, Straif K, et al. Research Recommendations for
Selected IARC-Classified Agents. Environmental Health Perspectives
2010:119(10):1355-1362.
• Presidents Cancer Panel. Reducing environmental cancer risks. U.S.
National Cancer Institute, April 2010.
• Demers PA, Peters CE, Nicol AM. Priority Occupational Carcinogens for
Surveillance in Canada: Preliminary Priority List. CAREX Canada, 2008.
• Hohenadel K, Marrett L, Pichora E, Brown J, Harris S, Blair A.
Occupational Cancer Research Centre Stakeholder Consultation Report.
OCRC, November 2009.
All reports are available at: http://occupationalcancer.ca/topics/information-resources/reports/

High Priorities (occupational) Medium priorities (occupational)
Asphalt & bitumen*
Carbon-based nanoparticles
Crystalline fibres other than asbestos
Ultrafine particles
Motor vehicle exhaust emissions
Perfluorinated compounds (e.g. PFOA)
Radiofrequency electromagnetic fields*
Sedentary work
Stress
Iron & iron oxides
Welding
Atrazine
Metalworking fluids & lubricants
N-Nitrosamines*
Polybrominated biphenyls (PBB)
Polybrominated diphenyl ethers (PBDE)
Polychlorinated biphenyls (PCB)
DEHP and other phthalates*
Styrene
Trichloroethylene & other chlorinated solvents
* IARC review already scheduled

Ultrafine particles
Titanium dioxide
Carbon black
Diesel Engine Exhaust
Welding fumes
Metals
Lead & lead compounds
Indium phosphide
Metallic cobalt
Pesticides
Atrazine
Shiftwork
Chlorinated solvents
Trichloroethylene
Perchloroethylene
Methylene chloride
Chloroform
Other Chemicals
Formaldehyde
Styrene & Styrene-7,8-Oxide
Acetaldehyde
Propylene Oxide
Polychlorinated Biphenyls (PCBs)
Di (2-ethylhexyl) phthalate (DEHP)

• Both the IARC Monograph Program and the
NIOSH priorities focus on contributing to the classification of suspected carcinogens
• Research on established carcinogens?
– Some are defined only by job or industry (e.g. painting & welding) and targets for prevention are needed
– Some are poorly defined (e.g. wood dust)

OCRC Stakeholder Needs Assessment Survey
Most frequently identified exposures
Exposure category Examples of commonly listed exposures
Chemicals
Dusts and fibres
Formaldehyde, amines, PCB, sulphuric acid mists…
Asbestos, fibreglass, silica, wood dust, carbon black
Radiation
Lifestyle factors
Shiftwork
Pesticides
Nanomaterials
Exhaust
Metals
Electromagnetic fields, nuclear, cell phone, solar, ionizing radiation, radiofrequency radiation, WIFI…
Smoking, physical activity, stress, diet, alcohol
--
--
--
Diesel, gasoline
Uranium, chromium, cobalt, gold, nickel, smelter fumes, tungsten, welding fumes, lead
Work environment Indoor air, environmental tobacco smoke, mould
Solvents
Fossil fuels & oils
Pharmaceuticals
Solvents (general), benzene, trichloroethylene…
Metal working fluid, oil mists, coal tar, fuel, asphalt
Antineoplastic drugs, cytotoxic drugs
Frequency
30
27
24
12
9
7
4
18
16
15
14
14
13

• 1991 Long-Form Census
– Representative 20% sample of population
• Linked to:
– Canadian Mortality Database
• Vital statistics
– Canadian Cancer Database
• Cancer incidence registry
– Tax Summary Files
• Derived from personal tax returns
• Follow-up: 1991 – 2003 (to be extended to 2005)

Canadian
Census Cohort
N = 2,734,800
Men
N = 1,342,100
Women
N = 1,392,700
Working
N = 1,123,500
Working
N = 953,600

• Insert screen shots for CAREX Canada site here (no worries for translation since available in both languages)