Questions answered

Questions asked by other people

Anne Wells responds:

The European Commission has proposed occupational exposure limits (OELs) for 13 carcinogenic substances, including respirable crystalline silica and a reduced OEL for hardwood dust.

They are:

  • Respirable crystalline silica (RCS); 0.1mg/m3
  • Hardwood dusts; 3mg/m3 (from7.77mg/m3)

The substances are among 20 priority chemical agents for which the Commission is conducting scientific and economic assessments with a view to preparing harmonised OELs across the EU. A second proposal covering the remaining substances will be issued by the end of the year, once further preparatory work is completed.

The other 11 of the latest 13 proposed are:

1,2-epoxypropane; 2.4mg/m3;
1,3-butadiene; 2.2mg/m3;
2-nitropropane; 18mg/m3;
acrylamide; 0.1mg/m3;
bromoethylene; 4.4mg/m3;
chromium (VI) compounds; 0.025mg/m3;
ethylene oxide; 1.8mg/m3;
hydrazine; 0.013mg/m3;
o-toluidine; 0.5mg/m3;
refractory ceramic fibres (RCF); 0.3 f/ml; and
vinyl chloride monomer (VCM); 2.6 mg/m3 (from 5mg/m3).

Cancer is responsible for half of all work-related deaths in the EU, but currently only three substances are subject to binding OELs under the carcinogens and mutagens Directive: benzene, hardwood dust and vinyl chloride monomer.

Currently our EH40 has a WEL of Respirable crystalline silica (RCS); 0.1mg/m3. However, for hardwood dusts we currently have a WEL of 5mg/m3, so this will eventually be reduced.

Link to EH40 below:

Jo Carter responds:

There is no law on the requirement for using sun cream, however health and safety law puts a duty on employers to protect employees. The risk assessment should identify control measures to put in place to eliminate or reduce the risks. However if the employer has identified sun cream as protection in the risk assessment then they will have to provide it.

It’s better to try to avoid solar radiation exposure, but if you have to work outdoors then cover up using protective clothing, before resorting to sunscreen. The HSE encourages employers to provide advice on sun protection for those who work outside for most of the day. This includes using sun cream to prevent long term health damage – one of the disadvantages of sunscreen is that the user may fail to apply it to all exposed areas of skin. Another is that the user may fail to re-apply sunscreen when required and can also be allergic to the creams.

Please see our No Time to Lose campaign solar radiation resources pack which contains materials to help raise awareness of solar radiation exposure including tool box talks, posters and factsheets.

Phil Bates responds:

The 666,000 figure comes from the World Health Organization (WHO), who is the world expert on health.

It is not scientific to look at products, all the research was done on the chemical components because otherwise all products containing the substance would have to be tested and compared against each other.

The majority of the data comes from RR931 and the British Journal of Cancer Research. The epidemiologists explain the latency issue which has been taken into account and the researchers believe the figures are a large under estimate of the true figures. The Carcinogens studied were Group 1 and Group 2A.

The No Time to Lose article in the SHP, November 2014 issue, page 51-54 has further information and a list of references.

It is always best to clean such areas by methods that do not disturb the dust, i.e. vacuum instead of dry brush, and damp or static dust rather than dry dust. The rubber particles from your description seem very visible so they would be of a size where the cilia in your respiratory tract would remove those that were inhaled

Absolutely, shiftwork is an essential part of society now, the NHS, emergency services, aviation, transport and many other industries would not function without shiftwork.

As the mechanism of how shiftwork causes cancer is not completely understood and there are many different types of shiftwork, it is difficult to say how to prevent it. There is a lot of research going on and the HSE is doing a large study that should be published in 2016. This research might indicate that the risk of cancer from shiftwork might only affect those people who have done shiftwork for a long time, perhaps 20 years or more. Shiftwork is also known to cause other health problems, so the best advice at the moment is to follow the HSE guidance on shift work published in HSG 256. It is also worth raising awareness of the signs and symptoms of breast cancer in women that regularly work night shift.

Professor John Cherrie responds:

It’s true that the standards for diesel emissions have been improving steadily over the last 20 or more years, and many people are now of the view that modern diesel engines are ‘safe’, at least in Europe and North America. The Euro 6 standard for light passenger and commercial vehicles has just come into force, and a new standard for emissions from trucks and buses came into force in 2013. Permitted particulate emissions are now almost 40 times lower than they were in the 1990s. However, we need to remember there are a lot more diesel vehicles on the roads in our towns and cities and this has offset some of the benefits from cleaner technologies. Also, there is a mixed fleet – both on the road and off road – with many older vehicles and plant still in service. It will therefore take time for exposures to decrease to levels that don’t pose a risk to worker health. In the meantime we need to think smarter about how to reduce risks.

Professor John Cherrie responds:

All diesel engines emit particles into the air. These are very fine particles that in moderate concentrations are invisible to the eye. The MOT test provides a way of checking that these emissions are not excessive, but it does not mean that there are no emissions. The test checks two things: 1) there is a Diesel Particulate Filter (DPF) present in the vehicle, assuming it was fitted when the vehicle was new, and 2) that there is not excessive smoke – essentially, visible blue smoke. It is really a fairly crude screening assessment to weed out the worst polluters.

Of course, MOTs in the UK only apply to on-road vehicles. Emissions from new off-road vehicles and other diesel engines used in construction, mining, quarrying, railways, agriculture etc have been regulated in the EU since 1997. However, these standards are less demanding than for on-road vehicles and there is no real ongoing assessment of the acceptability of engine emissions such as with the MOT test.

Ian Strudley responds:

Natural ventilation outside may provide adequate control but you need to consider how likely it is that workers will be exposed to diesel engine exhaust fumes, how many of them, to what extent, for how long and whether the exposures can be avoided. If exposure to diesel fumes is likely then other actions may be needed. Look at the guidance ‘Control of diesel engine exhaust emissions in the workplace’ (HSG187) on the HSE’s website.

Ian Strudley responds:

Diesel engine exhaust fumes are covered by the Control of Substances Hazardous to Health Regulations 2002. HSE inspectors look for prevention or control of exposure to hazardous substances in the workplace and will take enforcement action where risks of exposure are not effectively managed.


Ian Strudley responds:

It will depend on the type of diesel powered equipment and where it is being used but as with other hazardous substance exposure issues inspectors will want to be assured that the risks to health have been properly considered and the necessary steps identified to prevent or control those risks.

Dr Lesley Rushton responds:

The methods used for the British cancer burden study were developed with advice, discussion and peer review from international experts, including the International Agency for Research on Cancer, throughout the project and at two international workshops. They take account of issues such as the period in which relevant exposure would occur, changes in workforce turnover and employment trends, the potential to be exposed to several carcinogens at once and at different levels, and other important risks such as smoking. Confidence intervals around the burden estimates are available in the technical reports on the HSE website.  We are currently carrying out work to explore the sensitivity of the estimates to sources of uncertainty and bias in the data used.

The estimates include all occupational carcinogens evaluated by IARC up to the end of 2008 – since then IARC has updated these and identified new carcinogens. For example, ovarian, colorectal and pharyngeal cancers have since been added to the list associated with asbestos exposure. Our estimates are thus an underestimate of the true burden.

Dr Lesley Rushton responds:

Our research did not estimate the occupational burden separately by age group. Some occupational cancers are likely to occur before retirement, for example, skin cancers. But because of the long latency of many cancers, many occupational cancers are likely to occur after retirement age. For example, the average age of developing a mesothelioma from asbestos exposure is 60 and the average time from first exposure is 40 years.

Dr Lesley Rushton responds:

There are ongoing studies in Canada and Australia that are using/extending the methods we used. However, Australia has previously carried out estimation using much simpler methods and data. There have been quite a lot of papers in different countries before ours using a variety of methods but ‘The burden of occupational cancer in Great Britain’ is seen as the most thorough national study of its kind to date.

Dr Lesley Rushton responds:

We estimate that the risk of cancer over lifetime from occupational exposures is about 1 in 139 for men, and 1 in 431 for women – overall it’s about 1 in 216. So approximately 1 in 200 people will get an occupationally-related cancer at some time over their lifetime.

Phil Bates responds:

The burden of occupational cancer in Great Britain’ includes farming – it is ranked 19th in the industries that are known to cause occupational cancer fatalities. The report estimates that around 65 farm workers a year die from occupational cancers. Some of the cancers are a result of the chemicals they use – other causes, such as diesel exhaust engine emissions and solar radiation, are included in the numbers from the report.

Phil Bates responds:

The data used are from the industries specified by the HSE. Although aviation is not listed, some activities will be included in the metal working group and the manufacturing group.


Jane White responds:

More details of the industries and type of activities that are related to NHL are covered in the HSE research reports, so if you look at the tables in ‘The burden of occupational cancer in Great Britain’ you can see more detail. While the NHS is more focused on treating illness, it is the HSE and research establishments that spend more time looking at the clusters and causes. There is an epidemiology team at the HSE.

Jane White responds:

Some substances were once thought to be safe, but were later found out to be unsafe and quite harmful. Some nano tubules do look small and spindly, similar to asbestos fibres. But we are in a much better position now as we have COSHH requirements already in place and people are treating new technology with a reasonable amount of respect and monitoring potential hazards. IOSH has funded some research into nanotechnology, due to be published in 2017.

Jane White responds:

Chemical manufacturing is well controlled and COSHH has helped with that. Quite often, as was the case in the manufacture of dioxin-based herbicides in New Zealand, the people involved in the manufacturing were less exposed than those using the final product.

Phil Bates responds:

The International Agency for Research on Cancer lists over 50 substances as known or probable causes of workplace cancer. The IOSH campaign has selected five key issues to focus on: asbestos, diesel fumes, shiftwork, silica dust and solar radiation.

Asbestos, diesel exhaust emissions and silica were chosen based on the high number of cancer case registrations and cancer deaths associated with these exposures. While relevant data are drawn from UK research, we know that they are likely to be reflected in similar economies across the world.

Although shiftwork isn’t linked to as many deaths as other agents, it’s associated with a high number of cancer case registrations. It’s also a relatively hidden issue – many are unaware of the risks that researchers have found between long term disruptive shift patterns and breast cancer in women. We also decided it was worth focusing on as, unlike many of the other male-dominated issues, this particular link between work and cancer is associated with women.

While solar radiation isn’t associated with as high a number of deaths as some issues, the number of cancer case registrations are broadly comparable to those associated with mineral oil exposure in the UK. More than perhaps any other carcinogenic exposure, UVR exposure is quite easily controlled or prevented. We are also concerned about some attempts to dismiss it as a lifestyle or leisure issue, when the evidence clearly points to strong links between work exposure and cases of skin cancer.

Professor John Cherrie responds:

The truth is, statistics for confirmed cases of occupational cancers in the oil and gas sector just don’t exist.

Benzene is found in crude oil and natural gas, and benzene is known to be a risk factor for some types of leukaemia, particularly acute non-lymphocytic leukaemia (ANLL).  However, there is good evidence that current exposures in the industry are generally very low.  Other potential cancer risks offshore include mineral oil mist and vapour from drilling muds, asbestos fibres, formaldehyde, tetrachloroethylene, welding/cutting fumes, acids, and a small number of other materials.

There is good evidence for increased risk of leukaemia in the downstream oil industry, although the number of additional cases is likely very small. Rushton and her colleagues(¹) estimated that there were around 3,000 people in Britain exposed to benzene and as a consequence there are seven people each year who are diagnosed with ANLL, four of whom will eventually die. These were projected to occur among people who had worked in the wholesale and retail trade, bulk petrol sales and gasoline retail sites, land transport, and personal and household services.

Stenehjem and colleagues(²) recently published research on the cancer incidence of 41,000 Norwegian offshore oil workers. They found a small number of additional cases of leukaemia, malignant melanoma and lung cancer among the female workforce, and slightly increased numbers of bladder cancer among the men. The risk for mesothelioma was clearly increased in men with about 13 cases more than would have been expected. However, it needs to be remembered that cancer is a disease that mostly strikes in old age and the average age of the people studied was just 55 years. Earlier work in the Norwegian offshore industry had shown an increased risk for hematologic neoplasms (leukaemia and cancers of the bone marrow) for workers in the job category ‘upstream operator offshore’, having the most extensive contact with crude oil.

The pieces of the jigsaw puzzle are being pieced together every day. But we still need more research to be done in this important area.

¹ Rushton, L, Brown, TP, Cherrie, J, Fortunato, L, van Tongeren, M, & Hutchings, SJ (2010). How much does benzene contribute to the overall burden of cancer due to occupation? Chemico-Biological Interactions, 184(1–2), 290–292.

² Stenehjem, JS, Kjaerheim, K, Rabanal, KS, & Grimsrud, TK (2014). Cancer incidence among 41,000 offshore oil industry workers. Occupational Medicine (Oxford, England), 64(7), 539–545

Ian Strudley responds:

It depends on whether we are talking about occupational exposures or those experienced by members of the public.

At present, HSE advice is that employers assess the risks arising from exposures to potential high intensity EMF sources by comparing the environmental fields with the guidance issued by the International Commission on Non-Ionizing Radiation Protection – The EU has adopted a directive to restrict EMF exposures to workers that uses limits and action levels that are based on (but not numerically equal to) ICNIRP guidelines, but this does not have to be transposed into UK law until 01 July 2016.

Where exposures are to members of the public, the advice is to use the guidelines from ICNIRP, as expressed in the European Recommendation on restricting exposures of the public to EMFs (EC/519/1999). More advice on restricting exposures to the public, eg from powerlines, can be obtained from Public Health England, part of the Department of Health.

Professor John Cherrie responds:

It is understandable that you’re concerned about this development so close to where you live. There will have been proper consideration of the environmental pollution issues during the planning stages and the local authority will have a responsibility to check the site is working in accordance with the conditions of the planning permission. We think the key potential health issues for you and your family are related to exposure to diesel engine exhaust particulate and the fine dust from the quarry workings. It is unlikely that either of these will importantly increase the risk of cancer, and the most likely impacts would be in making asthma symptoms worse among people who already suffer from this disease. We advise you try to develop a relationship with the quarry operator and contact them if you think the operations are creating unacceptable emissions.

There is some good information on these websites:

And this scientific review article on the associations between environmental exposures and asthma control and exacerbations in young children may be of interest:

Jane White responds:

It’s not easy to define by occupation as the suspected harmful source chemicals are used in a variety of applications, ie not just printing. Statistics are scarce and difficult to sift.

The IARC has exposure data on printing inks:

You may find this information useful too:

Ian Strudley responds:

I’m not convinced that shop, restaurant, café and office workers are “exposed to almost constant diesel pollution”. I suggest the risk is minimal if windows, doors and/or air conditioning are used appropriately.

Clearly, any exposure to substances classed as carcinogenic needs to prevented as much as possible, but reasonable and practical control practices can and should be adopted.

Professor John Cherrie responds:

Rubber dust is not classified by IARC or any other authoritative source as a carcinogen. However, IARC has classified “working in the rubber manufacturing industry” as a group 1 carcinogen.

In the UK, the HSE introduced pragmatic measures for use in controlling exposures in rubber manufacturing plants. It defined two measures, rubber process dust and rubber fume, but the dust here is during the manufacturing, not once the products are in use.

You can find out more about the cancer risks from rubber manufacturing at:

And read this paper for a good introduction that summarises the issues:

I don’t think that tyres contain latex and I don’t know of any suggestions that tyre dusts cause asthma.

Professor John Cherrie responds:

The cancer risks from working as a fire fighter have been reviewed by the International Agency for Research on Cancer (IARC) and it concluded there was “limited evidence of carcinogenicity in humans”, and classified the occupation of fire fighting as “possibly carcinogenic to humans”.

There is good evidence that people in the fire service are exposed to many different carcinogenic substances, but the information about whether or not this results in an increased risk for the men and women who do this work is less clear. Part of the problem is that the work of a fire fighter differs depending on whether the person is working in a city or in the country, and whether it is in the UK or other parts of the world.

The results from the many epidemiological studies that have been carried out are inconsistent, with some suggestions of increased risks for multiple myeloma, non-Hodgkin lymphoma, prostate and testicular cancer. The latest publications from the USA and the Nordic countries show an increased risk of death from mesothelioma, a cancer of the lung that is known to be caused by exposure to asbestos. Fire fighters may be exposed to asbestos when tackling fires in buildings where asbestos-containing materials are present.  Previous epidemiological studies in the UK have not shown any clear health risks, but the last publication was nearly 20 years ago.

Fire fighters should be encouraged to reduce their risk of exposure to smoke and other pollutants when fighting fires. Protective clothing and respiratory protection should always be used during training, knockdown, overhaul and back-burning. It is possible that the skin can be a route of exposure and so fire fighters should ensure appropriate chemical protective gloves and clothing are worn when needed.

Employers are not obliged to provide sunscreen, but they can do if they want. It’s better to try to avoid exposure, and then cover up, before resorting to sunscreen. One of the disadvantages of sunscreen is that the user may fail to apply it to all exposed areas of skin. Another is that the user may fail to re-apply sunscreen when required.

The link below is the HSE’s response to a similar issue.


Dr Lesley Rushton responds:

The British cancer burden study included all carcinogens defined by the International Agency for Research on Cancer (IARC), a worldwide respected body, as a definite (group1) or probable (group 2A) human carcinogen (up to the end of 2008 when the study began – there have been further occupational carcinogens classified by IARC since then). IARC defined diesel engine exhaust (DEE) as a whole as a definite human carcinogen. However, the many chemical components of DEE were not evaluated separately by IARC as most of the studies available in the literature do not consider these. We estimated the burden of occupational exposure to DEE for lung and bladder cancers and our estimation took account of the effect of smoking. It should be noted that IARC have since considered the carcinogenicity of air pollution; DEE is an important source of particulates in the air.

Phil Bates responds: 

When an employer is considering controls during a risk assessment they need to use the principal of hierarchy of controls, i.e. elimination, substitution, engineering control, reduction, systems of work, and then personal protective equipment (PPE). Unfortunately, some people resort to PPE in the first instance rather than considering the hierarchy as they should do.

It’s better to try to avoid solar radiation exposure, but if you have to work outdoors then cover up using protective clothing, before resorting to sunscreen. One of the disadvantages of sunscreen is that the user may fail to apply it to all exposed areas of skin. Another is that the user may fail to re-apply sunscreen when required.

If an employer has identified sunscreen as a control measure in their risk assessment, then they will have to supply it.

It’s not just taxi drivers, but anyone who drives for a living can be exposed to potentially hazardous quantities of DEE.

This first French study conducted in taxi drivers shows that they are highly exposed to automobile pollutants.

Phil Bates responds: 

I assume the hand grinding is done with power tools and therefore likely to produce respirable dust. This work activity should be assessed and the appropriate controls should be used to reduce exposure. The dust produced should be measured and analysed by a competent person such as an occupational hygienist, who will be able to tell you what the content and quantities are. Any respirable dust can cause lung problems and exposure should be controlled to prevent illness. It is also important to know what is in the dust so you can determine the appropriate controls. There is guidance from the HSE in HSG 346 and eh2.