This is the introductory talk for a workshop session I gave at the British Occupational Hygiene Society (BOHS) conference in Manchester, OH2013.

1. INSTITUTE OF OCCUPATIONAL MEDICINE . Edinburgh . UK www.iom-world.org
Practical steps to control
exposure to workplace
carcinogens
John Cherrie

2. Plan for the workshop…
• Introduction (25 mins)
• Four agents(15 mins each)
• Crystalline silica
• Shift work involving night work
• Diesel engine exhaust
• Hardwood dust
• Final discussion (5 mins)
I hope that we can write a short article for the
BOHS Exposure newsletter?
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3. We know what to do…
• Minimise emission, release and spread of substances
• Take into account all relevant routes of exposure
• Control exposure by measures that are
proportionate to the health risk
• Choose the most effective and reliable control
options
• Where needed provide suitable personal protective
equipment
• Review regularly all elements of controls
• Inform and train all employees
• Ensure control measures do not increase overall risk
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http://www.hse.gov.uk/coshh/detail/goodpractice.htm

4. Control of exposure…
• Elimination
• Substitution
• Process modification
• Ventilation
• Isolation or segregation
• Maintenance
• Education and training
• Personal protective equipment
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5. Control of exposure…
• Elimination
• Substitution
• Ventilation and control at source
• Education and training
• Personal protective equipment
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6. Substitution…
• Successes
• Bladder cancer in the rubber industry and
β-naphthylamine
• Toluene for benzene
• However, substitutions are complex and may
have unexpected consequences
• use of citrus oil rather than trichloroethylene, but…
• d-limonene when oxidized presents risks as a skin
allergen
• Registries can promote substitution
• Plus, you have to get organisations to do it!
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7. ECEL…
• ECEL = Exposure Control Efficacy Library
• Review of literature on the effectiveness of
enclosures, local ventilation and other controls at
source
• 90 peer-reviewed papers
• Wide variation in effectiveness
• The data published since the ECEL report was
prepared broadly supports the original analysis
• Effectiveness in experimental or semi-experimental
studies higher than other situations
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Fransman et al. Development and Evaluation of an Exposure Control Efficacy Library
(ECEL). Annals of Occupational Hygiene (2008) vol. 52 (7) pp. 567-575.

8. ECEL
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Fransman et al. Development and Evaluation of an Exposure Control Efficacy Library (ECEL). Annals of Occupational Hygiene
(2008) vol. 52 (7) pp. 567-575

9. ECEL…
Risk Management Measure n Estimated
efficacy
(%)
95% confidence
interval
LEV in general 280 82 78 to 84
LEV + enclosure 9 86 69 to 94
Integrated 133 87 84 to 90
Mobile 4 61 -28 to 88
General ventilation 42 43 17 to 61
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10. Assigned Protection
Factors
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11. Nicas M, Neuhaus J. Variability
in Respiratory Protection and
the Assigned Protection Factor.
J Occup Environ Med
2004;1:99–109.
Effectiveness of
repiratory protection…
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12. Effectiveness of
behavioural interventions
• Results from a systematic review
• 550 potentially relevant articles identified
• 10 were considered informative
• Behavioural interventions had a limited
positive impact upon exposure
• It’s not sufficient to just raise awareness of
risks and controls, need to equip workers
with skills to act on that knowledge
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Lunt JA, Sheffield D, Bell N, et al. (2011) Review of preventative behavioural interventions for dermal and
respiratory hazards. Occup Med (Lond);61:311–20.

13. Control of exposure…
• Elimination
• Does what it says on the tin!
• Personal protective equipment
• Highly effective if you can get good compliance
• Substitution
• Potentially effective, but may be difficult to achieve in
practice
• Ventilation and control at source
• Very variable effectiveness, between locations
• Education and training
• No appreciable effect
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14. How do you get people
to act?
• Introduce new OELs?
• Provide free guidance material?
• Offer compliance support for organisations?
• Develop cost-effective technologies?
• Offer financial support to SMEs to introduce new
technology?
• Strictly enforce the law, e.g. COSHH?
• Require the introduction of new technology?
• Ban the use of the agent?
• Or something else.
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15. Crystalline silica…
• IARC 1 – lung cancer
• 5.3m exposed in Europe (4m in construction)
• Movement of earth (e.g. mining, quarrying, tunnelling)
• Crushing or grinding of silica containing material such as
concrete, aggregate or mortar
• Sandblasting
• Use of silica, sand or silica containing products in the
manufacture of glass and other non-metallic mineral
products
• Use of sand in foundries
• Geometric mean exposure 0.07 mg/m3 with a GSD
of about 5 (i.e. about 50% exceed 0.05 mg/m3).
• Maybe 7,000 deaths per year from past exposure
• OELs: mostly between 0.05 and 0.1mg/m3
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16. Shift work…
• IARC 2a – female breast cancer
• Perhaps 25,000 cases each year in Europe due to
shift working
• 15 – 20% workers work nights
• Health
• Machine ops
• Hotels, catering etc.
• Transport
• Wholesale
• No OELs, but risk highest for after midnight and
rotating night shift, particularly >500 shifts in
lifetime
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17. Diesel engine exhaust…
• IARC 1 – lung cancer and bladder cancer
• 3.6m people exposed in Europe
• Mining and quarrying
• Construction
• Transport
• 4,500 deaths per year in Europe
• Geometric mean exposure levels: 0.06 mg/m3 in
mining, 0.014 mg/m3 in transport (GSD about 3)
• Very few countries with OELs. Typical values
around 0.1 mg/m3, but a “safe” limit would be
around 0.01 mg/m3
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18. Hardwood dust…
• IARC 1 – sinonasal and nasopharyngeal cancer
• 3m people exposed in Europe
• Manufacture wood products
• Joinery
• Boat building
• About 160 deaths per year
• Geometric mean exposure in boat building
about 2 mg/m3 and otherwise about
0.5 mg/m3 (GSD 4)
• OELs between 1 and 5 mg/m3
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