Post on 24-Dec-2015
Exposure to solar ultraviolet radiation (UVR) in British Columbia’s outdoor workers
Cheryl E. Peters1,2 Sunil Kalia3
Paul A. Demers4,5
Anne-Marie Nicol2 Mieke W. Koehoorn1
1. School of Population and Public Health, University of British Columbia
2. CAREX Canada, Faculty of Health Sciences, Simon Fraser University
3. Dermatology and Skin Science, University of British Columbia4. Occupational Cancer Research Centre, Cancer Care Ontario5. Dalla Lana School of Public Health, University of Toronto
Background
Skin cancer = ~88,000 of ~269,000 new
cancer cases (2013)
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Health impacts from UV radiation
Ozone
Cloud cover
Latitude
Season
Air pollution
Elevation
Reflection
Outdoor work
Pattern of exposure Intermittent CumulativeBehaviour: Sun-seeking Sun-protective
Genetics: Skin colour Sun sensitivity
Cultural Dress Other behaviours
Immune competence
Melanoma
Squamous cell carcinoma (skin)Basal cell carcinoma (skin)
Solar keratoses
Sunburn
Cortical cataract
Pterygium
Cold sores
Sqamous cell carcinoma (cornea and conjunctiva)
UV radiation
Modified from ‘Global burden of disease from solar UVR’, World Health Organization, 2006
Number of outdoor workers in Canada
• 1.5 million exposed
• 8.8% of the working population
• Most of those exposed are men (82%)
Peters CE, Nicol AM, Demers PA. Prevalence of exposure to solar ultraviolet radiation (UVR) on the job in Canada. Can J Public Health. 2012. 103(3):223-6 3
The Outdoor Workers Project:Solar exposure in BC construction workers
Objectives:
1. To characterize ultraviolet radiation exposure in BC’s outdoor construction workers
2. To understand the determinants of solar UVR exposure
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Outdoor Workers Project: Methods
2. Questionnaire
3. Activity diary
1. UV dosimeter
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Results (1): Recruitment and demographics
Characteristic Outdoor workers Total number 78Sex (n males, %) 73 (95%)Age (mean, range) 38 (18 - 69)Race (n Caucasian, %) 73 (95%)Yes to childhood sunburn (n, %) 45 (58%)Blonde or red hair (n, %) 9 (12%)Light coloured eyes (n, %) 49 (64%)Skin types I or II (n, %) 11 (14%)
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Results (2): Exposure levels by job type
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Results (3): Exposure levels
MeasureOutdoor workers Controls
Number of measured days 346 46Standard Erythemal Dose resultsMean SED(burning threshold for un-tanned skin is 1.5-3 SED)1
2.3 0.38
SD 2.8 0.45Minimum <0.001 0.003Maximum 19.2 2.7UV Index resultsMean UV Index (full day) 0.3 0.04SD 0.7 0.3Minimum 0 0Maximum 12.3 5.9Mean UV Index (outdoor observations only) 0.8 0.6
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Results (4): Sunburn in outdoor workers by time spent outside at work
Outside up to 3 hours
4 hours 5 hours all day0
5
10
15
20
25
30
35
40
No sunburn1-4 sunburnsExcessive sunburns (>5)
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Discussion: Outdoor Workers Project
• Potential for solar UV radiation at work in the summer; levels differ by job site and are highly variable
• Workers are regularly getting sunburned at work
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Conclusions
• 1.5 million Canadians likely exposed to solar UVR on the job, evidence suggests inadequate protection
• Exposure levels in Vancouver summers are at high levels, sometimes dangerously so
• We have many challenges to address
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Acknowledgements– PhD committee:
• Mieke Koehoorn• Sunil Kalia• Paul Demers• Anne-Marie Nicol
– Brynn Bourke & The BC Building Trades
– Van Pile Ltd.– Seaspan / Vancouver Shipyard– JDG Construction– Environment Canada
(Atmospheric Monitoring)– WinVan Paving Ltd.– Arbutus Ridge Golf & Country
Club– Outdoor Workers Project
participants
Farming264,000 exposedResidential Building
Construction108,000 exposed
Services to Buildings
83,000 exposed
Foundation & Building Exterior
Contractors68,000 exposed
Amusement & Recreation
45,000 exposed
Examples of exposure patterns
7:12 AM 8:24 AM 9:36 AM 10:48 AM 12:00 PM 1:12 PM 2:24 PM 3:36 PM 4:48 PM 6:00 PM0
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Available UVWorker 1: Welding foremanWorker 2: CarpenterWorker 3: Traffic control
UV
Inde
x