WORKING FOR A HEALTHY FUTURE

INSTITUTE OF OCCUPATIONAL MEDICINE . Edinburgh . UK www.iom-world.org

Elimination of occupational cancer from hazardous substances

John Cherrie

Jeffrey Lee

• 32-year ACGIH member, he gave generously gave his time and talents to various committees and to the Board of Directors in 1987–88

• Helped establish the journal, Applied Occupational and Environmental Hygiene, and served as its Editor-in-Chief from 1990–1993

1944 - 1998

Summary…

• Workplace cancers are a concern• The current occupational cancer burden is mostly

caused by a small number of agents• Exposures have been decreasing steadily over time• Without any additional actions burden in the future

will be lower than now• Focused effort could ensure the occupational

cancer burden becomes much less than 1% of all cancers

• This would “eliminate” workplace cancer

Europe’s dirtiest factory…

• Malcolm Carhart died from lung cancer

• Fred Richards had bladder cancer and survived

• 300 other men who worked at the Phurnacite plant in South Wales had their health damaged by their work

Mr Fred Richards

This was a coal carbonization plant

Mortality in the plant…

• We carried out a mortality study in the plant in 1987• 17 year follow-up• 620 men included

• Increased mortality

• Non-melanoma skin cancer commonly reported

Lung Stomach Prostate Bladder Pneumonia COPD

SMR 146 160 152 270 189 139

President Richard Nixon started a war

• 23rd December 1971 he signed the National Cancer Act

• The main focus was on trying to find a cure, but there was a clear focus on prevention

• Strengthened the role of NCI

• This was the “War on Cancer”

Doll and Peto assessed cancer burden

• In 1981, they were commission by the US government to assess the relative importance of the “environment” in causing cancer

• Their aim was to identify the proportion of cancer that is preventable

Sir Richard Doll

Sir Richard Peto

75% and 80% of all cancers are preventable

Connecticut Low incidence registry

Typical US Low incidence

Attributable fractions…

About 4% (2 – 8%)

Cancer burden in the UK…

• Designed to update Doll and Peto’s estimate for occupational cancer burden• Current burden (2010) • Future burden (to 2060)

• Method based on:• Risk of Disease (relative risk from published literature)• Proportion of Population Exposed

• Estimation for IARC groups 1 (definite) and 2A (probable) carcinogens and occupational circumstances

•

Attributable fraction…

5.3% (4.6 – 6.6%)

Men = blueWomen = red

Cancer registrations…85% of the cancer cases come from the top ten chemical agents

- excluding ETS, which is already banned

Exposure decreases over time…

Creely KS et al. (2007) Trends in inhalation exposure--a review of the data in the published scientific literature. Ann Occup Hyg.; 51(8): 665-678.

Aerosols

Exposure decreases over time…

Creely KS et al. (2007) Trends in inhalation exposure--a review of the data in the published scientific literature. Ann Occup Hyg.; 51(8): 665-678.

Gases and vapours

16

1973 1974 19751

10

100

1000

f(x) = INF exp( − 2.00333226615499 x )R² = 0.740621920392391

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)VCM levels in a English PVC plant

Burden should be decreasing…

• If exposure is decreasing then it seems likely that the future burden will also be lower

• Assumes • Risk is related to exposure• Prevalence of exposure is not increasing• The aging population is not

distorting the picture

So what does the future hold?

• We have estimated future cancer burden in Europe and socioeconomic costs of interventions for a number of carcinogens• Exposure levels reliant on stakeholder data or when

unavailable published sources• Risk assessment reliant on epidemiological studies or

analogy• Health impact carried out using carefully reviewed

methodology developed for British cancer burden study • Socioeconomic assessment based on EC guidance

Estimates of future burden…

• Crystalline silica in Europe as an example:• 720,000 people exposed in Europe• 41% exposed above 0.05 mg/m3 • Current burden 7,600 lung cancers• 460,000 cases between 2010 and 2069• Cost of inaction between

€190,000m to €490,000m

Lung cancer registrations - baseline

Lung cancer registrations - intervention

The cost and benefits of intervention…

• Total net health benefits by 2069 from setting an OEL at 0.05 mg/m3 are €28,000m to €74,000m

• Costs of compliance estimated to be €34,000m• About half of these costs arise in

construction• Most costs fall on small companies

However, we could just wait…

What would “eliminate” really mean?

• Elimination of the disease as a public health problem (i.e. reduction of cases below what is considered to be a public health risk)

• What might be “a public health risk” for occupational cancer?

• Reduction of incidence to <<1% of all cancers?

For some substances we are already there

• In our assessment of current burden in Europe we estimate <20 cancers/year from past exposure for:• Vinyl chloride monomer 14 cases• 1, 3 Butadiene 2 cases• Beryllium 7 cases• Acrylamide 7 cases• MbOCA 8 cases• Ethylene oxide 0 cases• Refractory ceramic fibre 2 cases• 1, 2-Epoxypropane 0 cases• Bromoethylene 0 cases 1,100,000

Tracking progress…

• Periodic surveys of exposure by EU and national authorities• Intensity (including contextual information)• Prevalence

• Updates of cancer burden estimates • Routine reporting by occupational hygienists

through European occupational hygiene associations

A challenge…

• Focus on the top ten causes of the occupational cancer burden

• Ensure that exposures continue to fall by about 10% per annum

• We have eliminated the problem when an assessment of future burden from current exposure is <1% of all cancers

Acknowledgements…

• The work was in part funded by the British Health and Safety Executive (HSE) and the European Commission (EC)

• However, the views presented here are my own• Collaborators include:

• M Gorman Ng, A Shafrir, M van Tongeren, A Searl, J Crawford, A Sanchez-Jimenez, J Lamb (IOM)

• R Mistry, M Sobey, C Corden, O Warwick and M-H Bouhier (AMEC UK) • L Rushton and S Hutchings (Imperial College)• T Kaupinnen and P Heikkila (Finnish Institute of Occupational Health),

H Kromhout (IRAS, University of Utrecht)• L Levy (IEH, Cranfield University)

Questions…

• You can contribute to the discussion at www.OH-world.org

John.Cherrie@iom-world.org