Cancers are among the leading causes of morbidity and mortality worldwide with approximately 8.2 million cancer related deaths and 14 million new cases occurring in 2012. In 2007, the World Health Organisation estimated that there were 200,000 deaths from cancer related to the work place every year, which could have been prevented. It is estimated that there are now more than two million people in the UK who are living with cancer and over 700,000 of these are of working age. Martin Fenner of System Concepts reports.
Causes of occupational cancer
Occupational cancer is caused wholly or partly by exposure to a cancer causing agent (carcinogen) at work, or by a particular set of circumstances at work. Cancer is not a single disease with a single cause of treatment. It develops when cells in the body grow in an uncontrolled and abnormal way. There are numerous types of cancer, each with its own name and treatment, and different types of cancers have different causes. Many of these cancers can affect respiratory organs, the skin or liver. An individual’s risk of developing a cancer can be influenced by a number of factors including personal habits, such as smoking and alcohol consumption, genetics, personal characteristics such as sex, ethnicity, age, exposure to carcinogens in the environment and so on.
There are three different types of occupational carcinogens:
Biological Carcinogens — some micro-organism such as Hepatitis B, HIV viruses have been known to cause cancer either by damaging the cells or by decreasing the body’s ability to control abnormal cell growth.
Chemical carcinogens — a number of chemicals are known to be carcinogenic and may occur naturally, such as asbestos or be manufactured like vinyl chloride, or be part of a by-product of an industrial process.
Physical carcinogen — ionising and ultraviolet (UV) radiation have the potential to cause cancer. Examples of ionising radiation include X-rays and alpha, beta and gamma radiation. UV radiation can be divided into UV-B, UV-A etc., some of which are known to cause cancer.
The International Agency for Research on Cancer (IARC) has evaluated more than 950 agents for carcinogenicity. It published information in July 2014 on over 113 agents which are known as human carcinogens (IARC Group 1), 66 agents that were probable (IARC Group 2A) and 285 agents were possible (IARC Group 2B) human carcinogens.
A research project funded by the HSE, entitled The burden of occupational cancer in Great Britain, provided an estimate of the occupational exposure to both known and probable carcinogenic agents and exposure circumstances. The study involved obtaining data on the risk of cancer due to exposure to forty-one (IARC Group 1 and 2A) agents and was able to classify exposure to the sector and classification of work a person may have been in. The report provides information on the current burden from the previous 25 years occupational exposures, and investigates the future burden. The estimation of future cases is based on assumptions that the current trends of exposure and employment will continue up to 2030 and remain constant thereafter.
Impact of occupational cancer on the UK
Current estimates of occupational cancer have shown that about 8000 cancer deaths and around 13,500 cancer registrations per year in Great Britain could be attributed to past occupational exposure. The study has shown that past occupational exposures to asbestos is the leading occupational carcinogen, accounting for almost half of all occupational cancer deaths and a third of occupational cancer registrations. The trends indicate that the burden of asbestos related cancer caused by past occupational exposure will continue to increase. Other major carcinogens include silica, diesel engine exhausts (DEEs), mineral oils, in terms of their contribution to cancer deaths; and shift working, mineral oils and solar radiation in terms of their contribution to cancer registrations.
Exposures in the construction industry accounted for over 40% of the occupational cancer deaths and cancer registrations across all sectors. There were approximately 3500 cancer registrations attributed to the past exposure to asbestos and silica in the sector, mostly causing lung cancer and mesothelioma. An additional 1300 cancer registrations are attributed to solar radiation, coal tars and pitches, mostly causing non melanoma skin cancer. Although these are the headline carcinogenic agents, and industry sector, occupational cancer is prevalent across many different sectors and occupations as the following list shows:
Working as a hairdresser
Driving vehicles and mechanic (DEE)
Working in the rubber industry
Submariners (nuclear submarines)
Joiners working with hardwood and MDF
Nuclear power workers.
What can be done to eliminate and reduce exposure to occupational cancers?
Intervention scenarios have been used to test the possible impact on reducing occupational cancers, and indicate that there would be limited impact if, for example, the exposure standard was lowered. It was thought that most of the future occupational cancers associated with asbestos and DEEs will be attributed to large numbers of exposed workers at levels well below the current exposure standards. (See table: www.hse.gov.uk/statistics/tables/can08.xls).
It is essential that employers are aware of the risks of occupational cancers in their industry sector and the devastating effect that this has on individuals and their families. Employers have a responsibility under The Health and Safety at Work Act to ensure, as far as reasonably practicable, the health of their employee. It also states that employers must provide information, instruction, training and supervision to ensure their safety. This requirement not only covers an employee’s safety from immediate injury, but also their long-term health.
The Management of Health and Safety at Work regulations also require the employer to conduct a suitable risk assessment of risks to the health of the workforce. That includes any risks from hazards that may cause cancer. There are also legally enforceable levels of exposure to carcinogenic agents. These Workplace Exposure Limits are the absolute maximum levels to which workers can be exposed to, however, as previously stated lowering these exposure limits, may have limited impact on reducing occupational cancer.
The regulations make it clear that an employer must identify and then introduce preventative measures needed to improve workplace health and safety. The Management Regulations and Control of Substances Hazardous to Health Regulations (COSHH), lay down clear principles for prevention that must be followed when deciding what to do about a potential hazard. This means that the first step must always be, where possible, to get rid of the hazard altogether, removing any cancer causing hazard from the workplace. It is only once employers have tried to do this, should they look at whether they have to control the hazard. This is following the principles of the hierarchy of controls:
Elimination — Remove the cancer causing hazard or substitute with a non-carcinogenic substance.
Substitution — Replace the material or process with a less hazardous one. Care should be taken to use an alternative that is safer than the original.
Engineering controls — Use work equipment or other measures to control the risks, such as local exhaust ventilation to control risks from dust or fumes. Separate the hazard from operators by methods such as enclosing or guarding dangerous items. Give priority to measures which protect collectively over individual measures. Where appropriate carry out regular sampling of the work environment, such as the air, to identify if the engineering controls are working properly.
Administrative controls — Identify and implement the procedures you need to work safely for example, reducing the time workers are exposed to hazards, and ensure health surveillance is carried out at regular intervals.
Personal protective clothes and equipment — Only after all the previous measure have been tried and found ineffective in controlling risks to a reasonably practicable level, must personal protective equipment be used. PPE should be selected and fitted by the person who uses it. Workers must be trained in the function and limitation of each item of PPE.
It is estimated that the annual burden of occupational cancer in Great Britain exceeds £2 billion. If you add the cost of the care of the sick, lost wages and welfare payments, this can add hundreds of millions more to the bill. Most occupational cancers are preventable and therefore the debate with regards to it is whether trying to control it is sufficient, or whether elimination is the only way to save thousands of lives and reduce the burden on overstretched resources in the UK.
Last reviewed 26 June 2015