1. COPD and work SWOHN Exeter 2013 Paul Cullinan
Royal Brompton Hospital and Imperial College
London
LUNGS AT WORK

2. Outline
‘15% of all COPD is occupational’
what does this mean?
is it true?
what does this mean for OH?
note:
some abstract concepts
some controversy

3. What does this mean?
‘15% of all COPD is occupational’
the ‘15%’ is an attributable fraction
suggests that in a population, 15% of all COPD is caused by exposures at work
the figure is derived from studies of men in all sorts of jobs …
… and a comparison of the frequency of COPD in those with and without
exposure to respiratory irritants at work
VGDF
COPD

5. Problems ….
COPD is a little tricky to define and has other causes
definitions of COPD are centred on spirometry
unclear at what point there is ‘disease’
potential confounding
smoking
early life

6. Confounding
smoking
dusty work
COPD
early life

7. More problems ….
COPD is tricky to define and has other causes
definitions of COPD are based on spirometry (alone)
unclear at what point there is ‘disease’
potential confounding
smoking
early life
collecting unbiased information about people’s jobs
‘dusts, gases, vapours and fumes’

8. Is it true?
‘15% of all COPD is occupational’
… but only up to a point

9. Consider: British coal miners
2.4
2.4
low exposure
medium exposure
high exposure NS S
FEV1<80%
10%
17%
16%
27%
24%
40%
1.6
1.5
1.6
1.5

10. What we know about specific occupations
consistent or high quality evidence
moderate evidence
limited evidence
coal mining
welding
diisocyanate exposure
cadmium fume exposure
grain handling
asbestos
other agricultural work
coke oven work
textile dust exposure
iron or steel processing
silica
diesel fume

11. What does all this mean for OH?
do I need to be doing anything new?
should I be doing respiratory surveillance for COPD?
if so, how?
what do I say to the employee who asks me
“My doctors says I’ve got COPD. I’ve never smoked; is it because I work here?”

12. Introduction
your work involves dust, fume or an irritating substance that could cause COPD
COPD develops slowly, so it may take several years to tell if your employee’s lungs are working worse than expected.
it is long-term trends that are important, not 'single snapshots'.
it is estimated that 15% of COPD cases are caused by exposures at work. Smoking is the major cause of COPD, but you still need to control exposures to dust, fume or gas. Smoking makes work-related COPD worse.
if you detect an employee’s symptoms early enough and reduce their exposure, you will prevent further damage.

13. Substances
Coal-mine dust, silica, flour dust, grain, wood dust, metal fumes, and irritating gases such as nitrogen oxides and sulphur dioxide can all cause COPD. Some of these can cause other diseases too.
Occupations
Construction, mining, quarrying, welding, baking, dock work, some farming processes, textile work and stonemasonry are all associated with COPD.
You should consider monitoring your workers’ health if:
they use substances or are in occupations listed above;
are regularly exposed to dusts, noxious gases or fumes;
or breathe in mists, dusts, vapours or gases from products labelled R37 ‘Irritating to the
respiratory system’, R34 ‘Causes burns’ or R35 ‘Causes severe burns’.
If the risk of exposure is low in your particular circumstances, you may decide that health monitoring is unnecessary.
Where statutory health surveillance is in place for other respiratory diseases, such as asthma, any monitoring for COPD will be a secondary consideration.
Where there is a strong evidence base for a link between specific exposures and COPD then statutory health surveillance will be appropriate.

14. Planning and preparation
Plan what you are going to do if a worker shows signs of lung problems and make sure your employees are aware of your plans
Involve a health professional (doctor or nurse) in your health monitoring programme, they will help develop your scheme. Your health monitoring programme could include the following measures:
assess workers' respiratory health before they start a relevant job to provide a baseline (perhaps using a questionnaire and lung function assessment).
introduce regular testing as advised by the health professional. This could involve further questionnaires and lung function assessments.
the health professional must explain the test results to the individual and report to you on the worker's fitness to work.
health professionals should interpret the result trends for groups and individuals, and identify any need to revise the risk assessment.
you should appoint a responsible person, supported by the health professional, to report any symptoms that occur between tests.
keep a health record, and encourage workers to keep a copy of their results in case they change jobs.
keep simple attendance records to identify any patterns in sick absence.
What is it likely to cost?
health monitoring at your workplace costs an estimated £50 per person per test.

15. Chronic obstructive pulmonary disease (COPD)
We are not certain about the risk of developing COPD from RCS exposure.
It is good practice to monitor all workers exposed to RCS for signs of COPD.
What would this sort of health monitoring for COPD involve?
Involve a health professional (doctor or nurse) in your health monitoring programmes. They will develop your scheme.
This could include the following:
assess workers’ respiratory and other health before they start a relevant job, to provide a baseline (perhaps using a questionnaire and lung function assessment).
regular tests (as advised by the health professional) – this could involve a questionnaire and possibly lung function assessments. They should explain the tests results to the individual, and report to you on
the worker’s fitness to work.
the providers should interpret the result trends for groups and individuals, and identify any need to revise the risk assessment.

16. What am I looking for?
“a clinical diagnosis of COPD should be considered in any patient who has dyspnoea, chronic cough or sputum production, and a history of exposure to risk factors for the disease.”
“spirometry is required to make the diagnosis; the presence of a post-bronchodilator FEV1/FVC < 0.70 confirms the presence of persistent airflow limitation and thus of COPD.”
In patients with post-bronchodilator FEV1/FVC < 0.70:
GOLD 1: Mild FEV1 > 80% predicted
GOLD 2: Moderate % < FEV1 < 80% predicted
GOLD 3: Severe 30% < FEV1 < 50% predicted
GOLD 4: Very Severe FEV1 < 30% predicted
Volume, liters
Time, seconds 5 4 3 2 1 6
FEV1 = 1.8L
FVC = 3.2L
FEV1/FVC = 0.56
Normal
Obstructive

17. What am I looking for?
accelerated loss of FEV1
two rules of thumb:
>200 ml over each of 2 successive years or
‘500 ml in five years’

18. What am I supposed to do about it?
be a little wary about making a diagnosis on your own
consider referral to GP or specialist
confirm diagnosis or alternative
advise re. smoking
may suggest treatment
may make (in)appropriate suggestion about work
control exposure
assess fitness
RPE?
monitor

19. “My doctor says I’ve got COPD
“My doctor says I’ve got COPD. I’ve never smoked; is it because I work here?”
yes no
I don’t know ….
… and nor does anyone else
what matters is what we’re going to do about it
note: IIDB only for coalminers and those exposed to cadmium fume

20. RPE; an historical perspective
A Mr Abraham invented what was called a magnetic mouth piece to be used by the needle pointers and dry grinders.
This consists of a small frame of wood the upper and lower pieces of which are made circular to fit the lips. On this are fixed two or three layers of crape or muslin and it is studded with several small magnets calculated to arrest a considerable portion of the deleterious matter before it can reach the crape. To the upper part of this wooden frame is attached a bent wire to which crape is fixed for the purpose of protecting the nostrils and the whole is fastened by two strings passing round the head and tying behind. When these are strapped upon the face the air which enters the mouth and nostrils must pass between them and the ferruginous particles would consequently be attracted by and adhere to the magnets.

21. “We the under signed needle manufacturers at Redditch in the county of Worcester do hereby certify that we have examined and made trial of Mr Abraham's apparatus constructed for the purpose of preventing the ill effects of dry grinding generally and are of opinion that the said apparatus with the exception of passing off the stone dust is effectual and may be successfully applied for the use of needle pointers whose lives are sacrificed at an early period from twenty five to forty years of age in consequence of inhaling the small particles of steel dust ground from the point of the needle.
We therefore request you will lose no time in completing our order of the semi-circular frames of magnets as being best adapted for the use of the pointers that we may put all our pointers in the possession of them for we are convinced they will be found highly beneficial in preserving their health .”
Wm Bartlett and Sons
Richard Hemming and Son
Tho Williams
Wm Boulton and Son
Wm Field
W Dunn Needle pointer: his mark
W Adams Needle pointer: his mark

22. RPE; there’s nothing new under the sun
As might have been foretold however, without the gift of prophecy, those for whose use they were intended would not wear them.
These magnets were costly and as they must frequently be taken off to be cleaned they were very troublesome ...
... but worse than this they were very ugly and worst of all they excited the laugh and the jeers of the shopmates of those who wore them.