PO BOX 199 SHEFFIELD S1 4YL ENGLAND WWW.HAZARDS.ORG
Killed by work carcinogens
Bruce Ernest Barnard
The unremarked deaths of 18,000
Britain is facing a cancer epidemic which has
been almost entirely missed in official statistics. Hazards editor
Rory O’Neill reports on an occupational cancer crisis that is killing
50 people every day and calls for an urgent and fully resourced public
Jonathan Kay (right) died in August 2005 at the age of 40. Shortly before his death, he had learned his employer, Kelda Group plc – formerly Yorkshire Water Authority – had admitted liability for the asbestos cancer that was to kill him. Mr Kay, a graduate engineer and father-of-two, did not live long enough to discover how much compensation the firm would pay out.
Four months before his death from mesothelioma, a cruel and invariably fatal asbestos cancer, he said: “There was a level of dust that you could see in the air. You could taste it in your mouth.” Mr Kay said his employers never gave him protective equipment, even though the government had introduced strict regulations regarding the use of asbestos some 20 years previously.
”They should have provided me with appropriate guidance, information and equipment and none of that happened,” he said.
His solicitor Paul Webber said: “Jonathan Kay fought hard for justice for himself, but most importantly for him, for his young family. Despite clearly being in extreme pain, he continued in his quest… Although Jonathan did not live to receive the compensation, he died secure in the knowledge that his family would be protected.”
Jonathan Kay is one of a new generation of younger workers succumbing to asbestos cancers. Barry Welch (right) was just 32 when he died of the asbestos cancer mesothelioma in April 2005, his death the result of a cancer which until recently was assumed to be a disease of old age. His exposure to the fatal fibre is thought to have occurred in childhood, caused by dust on his stepfather’s work clothing (Hazards 91).
Neither Jonathan nor Barry had spent years in highly polluted heavy industry.
They form part of an emerging epidemic which authorities failed to spot
and, for the new generation of workplace killers, are doing precious little
More than one in three people in the UK will be diagnosed with cancer in their lifetime. One in four will die from cancer. More than a quarter of a million people in the UK are diagnosed with cancer every year (1).
Figures for England alone in 2003 put the total death toll for the year at 126,800. The UK figure for 2002 was over 155,000.
Cancer death rates in the UK have changed little since 1950, while the other major causes of death – heart disease, stroke and infectious diseases – have all declined. Cancer became the most common cause of death in females from 1969 and in males from 1995 (2).
It is a very modern killer. Cancer accounted for about 25 per cent of all deaths in England and Wales in 2000, compared to 15 per cent in 1950 and less than 5 per cent in 1901 (3). The number of people in the UK diagnosed with cancer is increasing, as is the proportion of UK deaths caused by cancer.
Lung cancer reports were relatively rare at the start of the 21st century. It did not even have an International Classification of Diseases (ICD) code until 1940.
The massive increase in smoking in the 20th century was an indisputable and major cause of the lung cancer explosion. But coincident with the explosion in smoking, was an explosion in workplace exposures to a continually widening pool of workplace substances that had been poorly studied and which were, for much of the century, poorly controlled.
While smoking cessation has become a major public health priority and has spurred an entire prevention industry, no similar campaign has been waged to address the carcinogens encountered and inhaled by millions at work. Primary prevention – removing the risks – could prevent all occupational cancers. But too little official regard for the risks has meant precious little regard for prevention.
No protection, no warning, no action
Jim Smith is recovering from a May 2005 operation to remove a tumour “the size of a pea” from his bladder. “I was having trouble going to the loo so went to the doctor. The doctor found blood in my urine.”
Jim joined the gas board in his mid-teens as an apprentice electrician. He worked at gas works around the north west producing “town gas”, where coal was heated to produce gas for industry and domestic use, from 1961 to 1969. He was made redundant as Britain’s North Sea natural gas supply came on line.
Since then he’s worked in “clean” jobs in offices and sales, and is clear where the blame lies for his health problems. “As an apprentice with the gas board they gave you all the crappy jobs to do. I had to climb into the retorts and fix lights for maintenance workers, but everything was covered in a tarry deposit. There was no discussion of health and safety and little by way of protection. If you were lucky you’d get a pair of gloves and a disposable mask – but you only got those if you made a song and dance. You even had to provide your own boiler suits.”
Working in the retort house, where the gas was produced, was known to be the dirtiest, most unpleasant job. “We had to climb into the retorts. When you went to shower you were covered in this brown stuff. It stuck to your skin. Since then I’ve had these marks, warts, on my body.” He also had to work under the large gasometers that used to be a common sight in major towns. “You were walking through this gunge, mire. I once sank up to my neck in brown, tarry gas waste. They had to hose me down and couldn’t even get it off then.”
The tarry waste is rich in polycyclic aromatic hydrocarbons (PAHs) and other toxins. Direct contact with the skin is known to lead to an increased bladder cancer risk in town gas workers. And Jim had other exposures to highly dangerous substances while doing the job. Carbon tetrachloride, a highly hazardous cancer causing solvent, was used in open bowls to clean off the oily deposit from machinery. Asbestos lagging was everywhere.
“I’ve been told the gas board was aware of the problems in the 1960s but didn’t do anything then,” says Jim. “I only found out the problem could be related to work when I contacted Sheffield Occupational Health Advisory Service (SOHAS) and Greater Manchester Hazards Centre. I’m a bit bewildered by it all. When the doctors told me I had cancer it was a shock. Then you start to ask why, what caused this, and you don’t get any answers. The medical people don’t want to get too involved, they are scared of being quoted.”
Since the operation Jim, now aged 59, has had trouble with his bladder, having to rush to the toilet at short notice and feeling understandably stressed. “I have to take a bottle with me in the car. My sleeping pattern has been thrown to hell. I’m going through all this now because of my early years with the gas board. I feel dreadful about it. I think the gas board had a duty of care to contact ex-employees to warn them of the risks and of the possible symptoms. Then maybe I’d have spotted my problem that bit sooner. They never contacted me. They never said anything.”
Jim’s is not an isolated case. Simon Pickvance of SOHAS, who first told Jim of the link between bladder cancer and work in town gas production says in the Sheffield area alone he has “seen several town gas plant workers with bladder cancer in the last three years.”
Keith McFadzien Jones was barely out of childhood when he first worked with asbestos. In February 2005 he was told, aged 50, those exposures in his youth had given him mesothelioma, an asbestos cancer few survive for more than two years.
“It’s terribly wrong,” he says. “I was an innocent, I left school, went to a place of work. I had been cared for all those years by my parents who handed me over to a firm as a bonded apprentice joiner hoping they would care for me. They did not provide that care, knowing how dangerous this stuff is.
“Asbestos board was everywhere, it was cheap. They were getting things done on the cheap, putting this stuff into thousands of homes.”
Keith was 15 when he was taken on by a joinery offshoot of Sheffield building firm Gleesons. “We were never warned about asbestos risks. We’d cut it, then eat our lunch at the same spot.” Keith worked periodically – sometimes for a few days, then maybe not for months – with “asbestolux”, an asbestos board with a relatively high asbestos content. He used disposable masks “for the sawdust. Everyone thought that was the greatest hazard, but the dust was always in your nose, like snuff. It must have been the same with the asbestos.
“We made it into firedoors and other panels. The foreman said it was asbestos-free and the company gave us no warnings. We were working quite willy-nilly with asbestolux. Being told it was asbestos-free made things worse, it was an open invitation.”
Keith left the firm aged 21, a qualified joiner, and believes that was the last time he worked with asbestos. By then, though, the damage was done. He first experienced symptoms, shortness of breath and “a pain like I’d been punched in the back” in September 2004, as he arrived in Russia on his honeymoon. He has not been able to work since 21 November 2004 because of his mesothelioma, a cancer his surgeon told him was “a living hell.” According to Keith: “I was desperately short of breath. It was just as though someone is stood on top of my chest and I couldn’t breathe.”
He has since had a radical extrapleural-pneumonectomy, a rare, experimental procedure in the UK which involved him “being opened up front and back” to remove the tumour that encircled his chest cavity. Surgeons say it is about the most extreme operation a human body might survive. He’s had chemo- and radiotherapy and is taking 24 different tablets a day, including morphine-based painkillers. He knows all this is probably an effort to extend his life, not cure him.
“I want to live as long as I can. I know how deadly the thing is but at least I’ve been given a chance. When I was diagnosed I was devastated, brokenhearted, but because of my family and my Christian beliefs I have pulled myself together. I have a new wife and three kids and two grandkids. Another grandchild is due in January.”
He now receives a disability pension but his wife, who is Russian and who has to care for him, receives nothing. “My wife can’t claim anything because she is not a UK citizen. But it’s her that is having to get up in the night because I feel unwell, who has to take care of me. It’s so unfair on her.
“I just plod on and keep going but it devastates families. My eldest, a teacher, became ill with stress – he’d thought dad was indestructible. I hope my story leads to more awareness and prevention, so others don’t have to go through this. These industrial cancers, then tend to ignore them. This is a bloody problem and is going to be in the future.”
These cases are not exceptional. Tens of millions of UK workers have faced deadly risks at work in recent decades. They were not warned of the risks. They were not provided protection. And their employers did not track them down to issue potentially lifesaving guidance on the need for vigilance and health surveillance. And the response of the UK government and safety authorities has been just as complacent.
• Colin Dyal - living with mesothelioma. Full
Working out the relative contribution of lifestyle, diet, pollution, occupation and other factors to the overall cancer toll is at best informed guesswork. The Health and Safety Executive’s cancer webpages, updated in 2005, give HSE’s best guess. It says: “Our current best estimate is the proportion of cancer deaths in Great Britain due to occupational exposures over the last few decades is 4 per cent, with an associated uncertainty of 2 per cent to 8 per cent. Applying these estimates to the latest five year’s mortality data for Great Britain provides an estimated annual number of cancer deaths from work-related causes of 6,000 (uncertainty range 3,000 to 12,000)” (4).
This HSE estimate is cribbed from one study, which concluded cancer was overwhelming a “lifestyle” issue (5). HSE said: “An important estimate of the overall proportion of cancer attributable to occupational causes remain that put forward by Doll and Peto in 1981 in a report to the US Congress. They estimated that 4 per cent (plausible range of certainty 2 per cent to 8 per cent) of cancer mortality was due to occupational causes.”
It added: “Although, this estimate relates to the US over two decades ago, it is seen as broadly applicable to Great Britain today and remains the best overall estimate available.”
An annual total of 6,000 deaths from occupational cancer is certainly a major public health concern. It is almost double the annual number of deaths on the road and is more than 20 times the number of workplace fatalities each year.
However, HSE has got things badly wrong in two respects. Firstly, a cursory glance at occupational cancer deaths in the UK quickly reveals HSE’s figures do not reflect the real toll. Official figures show 1,874 people died of the asbestos cancer mesothelioma alone in 2003 (6). Its notoriously inadequate occupational cancer reports picked up 616 occupational skin cancer cases in 2004 (4). The figure is approaching HSE’s lower estimate and we have only looked at two cancers, and lung cancer – far and away the most common and most deadly occupational cancer – isn’t included at all yet.
Doll/Peto estimated work accounted for 15 per cent of all lung cancers in American males, which would equate to over 3,000 deaths in UK males in 2002. A 2005 British Medical Journal paper put the number of work-related passive smoking lung cancer deaths alone at 160 in just one year (7).
Asbestos related lung cancers alone will at least match the mesothelioma total (8).
What HSE doesn’t say is that the Doll/Peto figure is just one of a number of estimates, and is much lower than many of the other estimates reported in the literature. A simple investigation of Doll/Peto’s methods reveals they produced a figure that by design fell considerably short of the true toll. How far short is a matter of debate, but in terms of deaths per year, we are talking thousands.
Even Doll/Peto acknowledged their estimates amounted to no more than informed guesses, noting it was “impossible to make any precise estimate of the proportion of the cancers of today that are attributable to hazards at work.” It is possible to identify significant flaws in Doll/Peto which mean it can only be a large under-estimate of the true toll.
This was good news for some, but a death sentence for others. “The companies were ecstatic when Doll/Peto came out, because it posed the whole thing politically as a lifestyle issue,” Stirling University occupational cancer authority Dr Jim Brophy (right) told Hazards. “That had consequences for prevention, in that it effectively ended any chance of a structured and well resourced strategy to combat occupational cancer.”
The impact of the ensuing occupational cancer epidemic went beyond traditional industrial jobs. Ex-teacher Alan Anthony died aged 72 on 27 May 2005, his mesothelioma linked to renovation work in the school he worked at in the 1970s. Hairdresser Janet Watson, who had worked in hair salons for 30 years, died aged 59 from the same condition. Her death in September 2004 was judged to be “death from an industrial disease” at inquest, caused by the asbestos commonly used in old-style hood hairdryers. Neither of these deaths would have been included in the HSE-approved cancer estimates – teachers and hairdressers didn’t figure in Doll/Peto’s at risk group.
Neither did health workers. Hospital consultant James Emerson died aged 45 from mesothelioma caused by exposure to damaged asbestos lagging in a hospital during his time as a medical student and junior doctor.
Thousands have gone on to die from cancers they just shouldn’t have developed, at least according to the Doll/Peto estimate, including the family members of workers exposed to asbestos, who got a second hand “paraoccupational” dose from the contaminated clothes and hair of a family member. And asbestos is just one of many potent occupational carcinogens encountered by millions in Britain’s workplaces.
HSE, however, embraced the Doll/Peto figure. The result has been little
priority paid to the prevention of most occupational cancers, creating
one of Britain’s most lamentable, preventable public health disasters.
Two major US reports published shortly before the Doll/Peto report – one from US government organisations (9) and another backed by employers’ organisations – put the occupational cancer contribution at at least 20 per cent of all cancers, with the industry-backed report conceding occupational cancer constituted “a public health catastrophe” (10).
A major review of environmental and occupational causes of cancer published in September 2005 (11) concluded: “It is difficult to estimate the impact of Doll and Peto’s views, but their 1981 article had been cited in over 441 other scientific articles by the end of 2004. More importantly, it has been cited repeatedly by commentators who argue that ‘cleaning up the environment’ is not going to make much difference in cancer rates.”
While industry groups and HSE embraced the Doll/Peto estimates, others were more critical. Hazards magazine warned in 1996 that the estimate “was always suspect and is now totally discredited” (Hazards 58). A 1995 paper in the Mt Sinai Journal of Medicine said the occupational cancer figure was too low and added it failed to take account of the limitations of the data on which it was based (12).
This paper and others noted that the Doll/Peto estimate was limited to an analysis of deaths in those under the age of 65. Cancer is primarily a disease of the old – only 26 per cent of the deaths in England in 2003 were in people under the age of 60 (3), so it is likely the great majority of occupational cancers would have been omitted from the figure.
Occupational cancers by definition only occur in those of working age and above and, because of latency periods before the development of disease, many are likely to emerge in old age. We have an aging population – as other causes of death decline more are likely to survive long enough to develop their occupational cancers.
Doll/Peto not only top sliced the numbers, it only considered cancer risks posed by a list of 16 substances or industries. The International Agency for Research on Cancer (IARC), however, classifies 89 substances as definite human carcinogens, 64 as probable human carcinogens and 264 as possible human carcinogens. A 2004 paper in the journal Environmental Health Perspectives reported that this included 28 definite, 27 probable and 113 possible human occupational carcinogens (13).
Occupational cancer risks to women are almost entirely ignored in the Doll/Peto analysis, which concentrated on jobs which in the preceding decades had been largely the preserve of men (14).
And Doll/Peto excluded African-Americans from the analysis, a group over-represented in high risk jobs and with higher and increasing cancer rates.
The impact on occupational cancer incidence of the synthetic chemicals produced in unprecedented volumes in recent decades would not have been estimated in Doll/Peto’s analysis – this only considered a small number of well established cancer risks - but could have been predicted on the basis of limited human evidence and more extensive toxicological and animal studies.
According to Dr Lorenzo Tomatis, who until 1993 headed the International Agency for Research on Cancer (IARC) programme evaluating chemicals, there is a marked double standard in operation when it comes to proof of risk.
“A necessary requirement for declaring an environmental chemical carcinogenic to humans is that conclusive epidemiological studies support a causal relationship, and particularly robust evidence for an association between occupational exposure and human cancer is required because a causal association is accepted, while the evidence for a contribution of dietary factors to the cancer burden is usually circumstantial and, in come cases, rather weak,” he said.
He told a Collegium Ramazzini conference in September 2005: “Punctilious precision is used in calculating occupational and environmental risks, while a wide latitude is allowed for risks related to diet, ranging between 10 per cent and 70 per cent.” He added that Doll/Peto acknowledged that occupational cancinogens “tend to be those which increase the risk of some particular type(s) of cancer very substantially,” and others might not have been detected simply because they have not been investigated or because the exposure concerned a small number of individuals, and no suspicion was raised.
The end result is that cancers are attributed a “lifestyle” cause with relative ease, while production and use of occupational carcinogens continues unremarked and unabated. “The emphasis given to lifestyle factors, to the detriment of information on the role of chemical pollutants, favoured the uninterrupted production of agents with negative effects on health that remain hidden or secret or are deliberately underestimated,” said Tomatis. “Furthermore, attributing most cancer cases to lifestyle, which is related to free personal choice, unduly amplifies the individual’s responsibility, diverts attention from the lack of commitment of health authorities and obscures the aetiological role of other risk factors.”
Some observers are unsurprised at the conclusions of the Doll/Peto report. Sir Richard Doll, co-author of the 1981 report that informed HSE’s cancer strategy for quarter of a century, was a favourite expert of some of the world’s most hazardous industries. In court depositions in 2000, he admitted T&N, Britain’s most prolific asbestos killer, had donated £50,000 to the Oxford college where he was warden “in recognition of all the work I had done for them.” [see The great work cancer con below]
According to Dr Richard Clapp (right) of the University of Boston Medical School, co-author of the September 2005 review (11): “Using the 1981 Doll/Peto estimates for occupational cancer probably underestimates the occupational exposure contribution by a factor of two to four in both the US and the UK.” This would mean an occupational contribution to the UK cancer total of between 8 and 16 per cent.
Dr Clapp told Hazards: “I believe occupational lung cancer is the leading work-related cancer followed by bladder cancer, non-Hodgkin's lymphoma, and leukaemia. Our review paper gives the scientific studies which back this up, along with the various exposures that cause these cancers.
“For example, for lung cancer, we review the evidence that metals, solvents, ionising radiation, reactive chemicals like BCME, environmental tobacco smoke, air pollution, polycyclic aromatic hydrocarbons, pesticides and fibres like asbestos and silica cause lung cancer. This adds up to a substantial burden, and some of these exposures - like asbestos and ionising radiation in underground miners - act synergistically with cigarette smoke and vastly increase lung cancer risk.”
He added “there is no way to put a precise number on this because cancer is such a ‘multifactorial’ disease and even small exposures can be a critical piece of the pie when lots of people are exposed. The reason we have so much cancer is because we are exposed to so many carcinogens; we need to turn that around both by producing and using fewer carcinogenic materials and not exposing workers and others to them.”
Dr Samuel Epstein, emeritus professor of environmental and occupational medicine at the University of Illinois at Chicago, puts the occupational figure in the Clapp range, saying “based on minimal estimates” occupational carcinogenic exposures are responsible for 10 per cent of overall cancer mortality adding that for certain occupational exposures, mortality rates are much higher (15).
He said “lifestyle academics” including Sir Richard Doll “have consciously or unconsciously become the well-touted and enthusiastic mouthpiece for industry interests, urging regulatory inaction and public complacency”, adding the “puristic pretensions of ‘the lifestylers’ for critical objectivity are only exceeded by their apparent indifference to or rejection of a steadily accumulating body of information on the permeation of the environment and workplace with industrial carcinogens and the impact of such involuntary exposures on human health.”
According to Epstein, any adherence to the Doll/Peto figures is folly because their paper “excluded from analysis people over the age of 65 and blacks, just those groups with the highest and increasing cancer mortality rates. Not content with such manipulation, they claimed that occupation was only responsible for 4 per cent of all cancers, without apparent consideration of a wide range of recent studies dealing with the carcinogenic effects of such exposures… The wild 4 per cent guess was matched by ‘guesstimates’ that diet was determinant in some 35 per cent of all cancers.”
Professor Andy Watterson (right) of Stirling University’s occupational and environmental health research group, believes Clapp’s estimate of real occupational cancer incidence “is about right” and is critical of HSE for failing to act on “significant and serious health risks from workplace carcinogens.
“Lung cancers caused by asbestos exposure are not picked up and other occupational cancers simply do not show up on the official radar; the contribution of work to breast cancers is widely neglected and there are a number of carcinogens that attack humans – brain, nervous system, soft tissue sarcomas, cancer of the larynx, kidneys, stomach, bone – which are not adequately regulated.”
Even at Clapp’s lower estimate of 8 per cent of all cancers being work-related, the UK figure would be of the order of 12,000 deaths a year and about 20,000 new cases. Whichever figure you choose, the loopholes in Doll/Peto’s analysis mean the UK’s official estimate of 6,000 occupational cancer deaths certainly misses thousands of deaths a year. The shortfall on new cases is more marked still, falling short by well in excess of 10,000 cases a year.
Some occupational cancers ignored in
the UK are not just recognised, but are also officially compensated in
other jurisdictions (see
Cancer in Canada, coincidence in UK below).
HSE’s practical disaster
HSE has a reluctance to raise the spectre of occupational cancer risks, even where they are well established.
A webpage on metalworking fluids created in 2005 (16) omitted entirely any mention of cancer risks. Dr Frank Mirer, director of the US autoworkers’ union UAW wrote to HSE saying: “I find the omission of a mention of occupational cancer in the new page or metalworking fluids to be a significant gap.” He pointed to a series of papers showing an occupational cancer risk (See HSE metalworking fluids guide ducks cancer issue, below).
On a rare occasion HSE did revisit its occupational cancer estimates, it revised them down. It now says the ratio of asbestos related lung cancers to mesotheliomas may be lower than 1 to 1 – a 2005 HSE paper puts the ratio of asbestos lung cancers to mesotheliomas at between 2/3 and 1 to 1 - much lower than many other estimates (17).
The authors acknowledge their figure will miss some cancers because it under-estimates the effects of chrysotile (white asbestos), which has been the dominant exposure since 1970. And their analysis only includes cancer deaths up to the age of 74, whereas many asbestos related lung cancer deaths occur in older workers.
While many observers believe the ratio of asbestos-related lung cancers to mesothelioma may be closing as fewer workers are experiencing the very high exposures which were linked to much higher numbers of lung cancers and a drop in smoking will reduce those caused by the synergy between smoking and asbestos exposure, HSE’s new estimate is significantly lower than generally cited figures. Stirling University’s Dr Jim Brophy described the lower estimate as “garbage”.
Dr Joe LaDou, editor of the International Journal of Occupational and Environmental Health, noted in 2004: “The number of lung cancer deaths caused by asbestos is at least equal to the number of deaths from mesothelioma. The ratio may be much higher than 1 to 1, with some reports suggesting up to 7 to 1” (18).
If the HSE estimates are troubling, the official records of actual cases are appalling. Even by HSE’s new low estimates, there should be between 1,220 and 1,870 asbestos-related lung cancers recorded every year. Official reporting schemes record fewer than 150 cases a year and the government’s industrial injuries benefits scheme for asbestos related cancers pays out to fewer than 100 people each year (6).
And while HSE may have stuck with Doll/Peto’s 1981 estimates of risk, a generation has gone by and new evidence has come to light, including evidence for cancers dismissed entirely by the report or only included in very limited circumstances.
A 2004 paper reported the risk of ovarian cancer increases with increased exposure to diesel exhaust at work. It found individuals with the highest cumulative exposure to diesel exhaust had more than 3.5 times the risk of ovarian cancer (19).
A 2005 paper concluded exposure to wood dust increased the chances of developing not only nasal cancer but also lung cancer, finding the risk of lung cancer was increased by 57 per cent with wood dust exposure in absence of smoking, by 71 per cent for smoking in the absence of wood dust exposure, and by 187 per cent for individuals who were exposed to both smoking and wood dust (20).
The Department of Health’s Committee on Carcinogenicity reported in December 2004 that “there was some limited evidence to suggest an association between farmers/farm workers, exposure to pesticides and increased risk of prostate cancer” (21). A September 2005 paper concluded exposure to polycyclic aromatic hydrocarbons (PAHs) dramatically increased the risk of laryngeal cancer, up by 5.2 times (22). A 2004 paper linked workplace exposure to the pesticide chlropyrifos to a doubling of the lung cancer risk (23).
What HSE has to say for itself
While HSE has stood still, the evidence has moved on. Evidence on pesticides and cancer, passive smoking and cancer, breast cancer linked to occupational exposures and shift work, the recognition of formaldehyde as an occupational carcinogen and a plethora of other studies all passed HSE by without comment.
A spokesperson for HSE told Hazards: “Doll and Peto’s 1981 estimate of the proportion of US cancer mortality due to occupational causes was based on knowledge about the scientific evidence on occupational cancer at that time.
“Over the past 20 years or so, we have made the judgment that we consider these estimates to be broadly applicable to the situation in Great Britain today. This judgment has mainly been based on the lack of discovery of any major new occupational carcinogens and better workplace controls including the banning and substitution of many carcinogens.”
He added that “work is underway to update the estimate,” and should be available by the end of 2006. A report of an HSE workshop on the “burden of occupational cancer in Great Britain”, based on an experts’ workshop held in November 2004, was published online in October 2005 (27). The participants agreed it was “timely and feasible to update Doll and Peto’s 1981 estimate.”
HSE’s sluggishness in researching and adopting a new, more realistic estimate has its critics. “Using their low estimates to set priorities, undoubtedly directs resources elsewhere that would otherwise be directed toward enforcing regulatory restrictions on occupational exposures, researching safer materials and processes, etc., resulting in more cancer in workers than need be,” said Boston University’s Dr Clapp. “This is an unjustifiable and avoidable public health burden.”
Stirling University’s Professor Watterson said: “Even the 4 per cent figure should have provoked a far stronger response from the Health and Safety Commission and HSE and the government than it has, with far greater priority given to developing prevention strategies.” He said road traffic accidents kill far fewer people and have been the subject of a concerted and effective prevention effort by authorities.
“I don’t see the resources available in HSC/E to pursue this important public health area. HSE seems very defensive, not looking at the subject of occupational cancer perhaps for fear of what it might find. We need less blether and more bite from HSE on effective strategies for removing known or suspect occupational carcinogens from the workplace – and more support for those with this group of occupational diseases.”
Low priority, high risk
Occupational cancer remains a low priority, a position in the nation’s public health priorities that can be traced back to Doll/Peto. And it is a low priority also reflected in the approach of health organisations other than the Health and Safety Executive. Cancer Research UK notes on its website: “Most known occupational carcinogens are either banned or well regulated within the UK and the majority of occupation related cancers diagnosed in the UK today are the result of people being exposed more than ten years ago” (28).
In fact, regulation has not been a cancer cure. Unlike the case of infectious diseases, where a response is frequently swift and draconian, there are typically long delays between the identification of a carcinogenic agent and adoption of adequate measures of prevention. Even then, measures are usually late and incomplete, and will leave a generation to await their fate as a result of prior exposures. Asbestos and ionising radiation are two clear examples. Contrast the decades of occupational health inaction to the foot-and-mouth disease outbreak in 2001, where the army was deployed and a national campaign was mobilised to deal with a non-fatal animal disease because it posed a commercial but absolutely no human health risk.
Instead, the assumption that it is “the dose the makes the poison” has been behind a piecemeal and slow, incremental reduction in workplace exposure limits, for workplaces where carcinogens are handled, quite literally, in industrial quantities. For many substances this presumed dose-response relationship is dangerous flawed.
The asbestos related cancer mesothelioma is a case in point, occurring now in people who had only incidental exposure to asbestos. Only a handful of workplace substances have ever been banned on grounds of carcinogenicity. A UK ban on asbestos - the most prolific ever industrial killer which may claim 10 million lives before it is banned worldwide (18) - only took effect in 1999. An early, precautionary move to safer alternatives would have saved millions. Commercial interests ensured that did not happen.
The result of the triumph of commercial interest over public health is that many occupational carcinogens are still encountered regularly in the workplace and today’s working generation is still being exposed to substances and environments that will cause tomorrow’s cancers. And the risk of exposure may, in fact, be increasing.
Figures from the French national statistic office DARES published in 2005 revealed more than 1 in 8 workers was exposed to workplace substances that can cause cancer. The analysis of the 2003 SUMER survey indicated that 13.5 per cent of the total French workforce was exposed to one or more of a list of 28 workplace carcinogens (29). The figure was higher than estimates a decade earlier. Blue collar workers were eight times as likely to be at risk, with 25 per cent exposed. Eight products, all common in UK workplaces, contributed more than two-thirds of all exposures – mineral oils, three organic solvents, asbestos, wood dust, diesel exhaust fumes and crystalline silica.
The European Union’s CAREX database of occupational exposures to carcinogens estimated that in the early 1990s 22-24 million workers in the then 15 EU member states were exposed to possible carcinogens. The most common exposures were solar radiation, environmental tobacco smoke, crystalline silica, radon and wood dust (30). The authors of a 2000 paper conclude that “a substantial proportion of workers in the EU were exposed to carcinogens.”
For Great Britain, it concludes: “According to the preliminary estimates, there were circa 5 million workers (22 per cent of the employed) exposed to the agents covered by CAREX in Great Britain in 1990-93. The number of exposures was circa 7 million.
“The most common exposures were environmental tobacco smoke (1.3 million workers exposed at least 75 per cent of working time), solar radiation (1.3 million workers exposed at least 75 per cent of working time), crystalline silica (600,000), radon and its decay products (600,000), diesel engine exhaust (470,000), wood dust (430,000), benzene (300,000), ethylene dibromide (280,000), lead and inorganic lead compounds (250,000), glasswool (140,000), and chromium VI compounds (130,000)."
By this estimate, over a fifth of the UK workforce has been exposed to possible human carcinogens and for these workers most of the resultant cancers will only emerge in a couple of decades or more.
But while the evidence of occupational cancer risk is increasing, there is no increased sense of urgency apparent from the authorities. In October 2005 the UK government refused to introduce a blanket ban on smoking in the workplace, choosing instead a legislative fudge which will leave many thousands of hospitality staff exposed to a passive smoking cancer risk. And the anti-regulation sentiment in the European Commission, heightened throughout a UK government European Union presidency which started in July 2005, saw proposed legislative action to reduce the occupational skin cancer risk from exposure to sunlight blocked in September 2005. Skin cancer rates in the UK have doubled in the last 25 years. By contrast Australia, with much higher potential exposures, took sensible preventive measures to reduce occupational risks, and now has a skin cancer incidence below that of the UK.
Cancers associated in studies with exposures to workplace
substances include the following.
Colon cancer Limited evidence for solvents
xylene and toluene and ionising radiation.
Liver and biliary cancer Ionising radiation;
vinyl chloride and angiosarcoma of the liver; PCBs. Some evidence for
arsenic, chlorinated solvents and reactive chemicals.
Prostate cancer Links to cadmium, arsenic and some pesticides, notably herbicides and other endocrine disrupters. Excess risks have been found for exposure to metallic dusts and metalworking fluids, PAHs and liquid fuel combustion products, and farmers and pesticide applicators.
Rectal cancer Metalworking fluids and mineral oils. Some evidence for solvents, including toluene and xylene.
Soft tissue sarcomas Vinyl chloride monomer (angiosarcoma of the liver); pesticides. Ewing’s sarcoma in pesticide exposed workers.
Skin cancer UV and sun exposure; metalworking fluids and mineral oils; Non-melanoma skin cancers from arsenic, creosote, PAHs, coal tars and ionising radiation.
Stomach cancer Ionising radiation; metalworking fluids and mineral oils; asbestos. Some evidence for solvents and pesticides. Excess risks found in workers in the rubber, coal, iron, lead, zinc and gold mining industries.
Testicular cancer Evidence for endocrine disrupting chemicals (eg. phthalates, PCBs and polyhalogenated hydrocarbons). A literature review found significantly elevated risks in men working in industries including agriculture, tanning and mechanical industries, and consistent associations with painting, mining, plastics, metalworking and occupational use of hand-held radar.
Thyroid cancer Ionising radiation.
Summarised from: Richard Clapp, Genevieve Howe, Molly Jacobs Lefevre. Environmental and cccupational causes of cancer: A review of recent Scientific literature. Lowell Center for Sustainable Production, University of Massachusetts Lowell, September 2005.
Even if we evaluate all the available evidence, we may not be evaluating the evidence we need, or evidence that honestly reflects the real occupational risks.
According to Stirling University’s Dr Jim Brophy: “The reaction of manufacturers that produce or employ products that might be deemed to be carcinogenic has at times been to suppress the damning research rather than to take steps to prevent harm to the exposed populations.” [see Industry’s deadly research role below]
Dr James Huff, who headed IARC’s chemical evaluation programme until 1980, said in 2003 that the agency had lost its position as “the most authoritative and scientific source” on cancer risks “due to the increasing influence of those aligned with the industry point of view regarding chemicals and their inert hazards to public and occupational health.” He found representatives with industry sympathies or affiliations routinely outnumbered those aligned with public health at IARC evaluation meetings (31).
In the decade from 1993, ratings for eight chemicals were upgraded, but 12 were downgraded. In the preceding decade, before industry asserted its influence on the decision making process, no IARC assessments were downgraded (Hazards 80).
In fact it can take a concerted campaign to get action to prevent cancer risks, even when the evidence of harm is overwhelming. A lowering of the maximum permissible workplace exposure levels for benzene was strongly resisted by industry, which is still resisting recognition of the risks of low concentrations (32).
According to Dr Lorenzo Tomatis, who headed the IARC programme until 1993, industry is now dictating terms. “The prevailing assumption, also used as an improper justification, was that the production of certain goods is necessary and vital, even when it was only aimed at increasing consumption of inessential goods, and that the risks involved in their production are an unavoidable price that society must pay.”
He said this “disregarded the evidence that the highest price is paid by a particular sector of the population, in which morbidity and mortality are considerably higher than those in the rest of the population.”
An unjust public health disaster
This unequal risk of occupational cancer means a minority of the population are facing an enormously elevated, serious and preventable risk. That risk is not being taken seriously and those cancer cases are not, on the whole, being prevented. Work-related cancer is far more common in blue-collar workers – there is an undeniable correlation between employment in lower status jobs and an increased risk (33).
Studies have found, for example, that 40 per cent of the lung and bladder cancer cases in certain industrial groups can be caused by occupational exposures (34). French statistics office figures published in 2005 found 1 in 8 workers were exposed to carcinogens at work, but that the figure was 25 per cent for manual workers and just 3 per cent for managers (29).
And the exposures causing these cancers are not the result of informed, lifestyle choices. They are the consequence of being required to spend the working day in a place that contains carcinogens and where decisions about how they are used and controlled are almost entirely outside the influence of the person facing the risk.
The asbestos cancer mesothelioma is one of the most stark examples. A 2004 British Medical Journal editorial on the UK asbestos cancer epidemic noted: “For a man first exposed as a teenager, who remained in a high risk occupation, such as insulation, throughout his working life, the lifetime risk of mesothelioma can be as high as one in five. There are now over 1,800 deaths per year in Britain (about one in 200 of all deaths in men and one in 1,500 in women), and the number is still increasing” (35).
According to the 2005 UMASS Lowell report (11): “Unequal workplace exposures among different populations provide further indications of the ability of occupational exposures to cause harm.” It adds that studies in the US steel industry found the highest rates of lung cancer – 10 times expected – were in non-white workers, employed in the highest risk jobs. This racial inequality in occupational cancer risks has been reported in a number of studies (36).
Long-term benzene workers are 30 times more likely to die of leukaemia, the UMASS Lowell report says, and adds: “More than half of asbestos workers have died of cancer and the relative risk of lung cancer among asbestos workers who smoke is 55,” or 55 times the general level in the population.
According to the CAREX report for Great Britain (29), all the workplace exposures to carcinogens were restricted to about one-fifth of the working population. If the occupational cancer risk was equal across the population, based on HSE’s figure of 6,000 deaths a year, this would equate to 1 per cent of all deaths being caused by occupational cancers in any given year. However, the responsible exposures are limited to a much smaller group who bear most of the risk, suggesting that 5 per cent or more of deaths in this group could be caused by occupational cancers.
According to Stirling University’s Dr Jim Brophy: “Even the lowest estimates of occupational cancer risk for the overall population translate to a 25 per cent risk in the exposed population. I think work-related cancer is being diluted as workers at high risk are thrown in with the general population. A revised public health strategy would emphasise government regulations and accountability to curtail worker and community exposures to carcinogens rather than relying on individual behaviour modification or allocating the bulk of research cash to discovering a cure for cancer.”
It is not just about prevention of cases of occupational cancer, it is also about efforts to make sure those cancers do not kill. For now, occupational cancer remains a virtually invisible killer. Those who have already faced the exposures that will result in them developing cancer are not being told of that risk and are not getting the surveillance that might allow an early and possibly lifesaving intervention.
Stopping work cancer dead
Brophy is among a growing body of occupational health professionals who think the Doll/Peto carve up of cancer by cause did a disservice to prevention efforts, not just by getting it wrong, but by failing to fully reflect the complexity of cancer causation. “The reason we don’t see any of the occupational cancers other than mesothelioma is because at any time there are multiple causes, and where the default designation is ‘lifestyle’.”
His colleague at Stirling University, Professor Andrew Watterson, agrees: “Good public health practice should now automatically recognise the multi-causality of many cancers and the significant part that work circumstances and related wider environmental factors will play.
“Instead we continue to have a narrow, skewed and flawed focus on lifestyle factors that ignore other exposures to carcinogens. This may reflect government policy which bends to the wishes of employers, pushes deregulation and doesn’t have an effective policy on or properly resourced structure to address occupational and occupationally-related cancers.
“The government should be leading here, removing known and suspected occupational and environmental carcinogens and not downplaying the risks and recognition of carcinogens.”
The 2005 UMass Lowell report (11) notes: “The least toxic alternative should always be used. Partial but reliable evidence of harm should compel us to act on the side of caution to prevent needless sickness and death. The right of people to know what they are exposed to must be protected.”
Dr Richard Clapp, co-author of the UMASS Lowell study, says: “Besides constant vigilance by worker health and safety advocates in unions, non-governmental organisations and academics, government enforcement of existing exposure limits, lowering these limits as new information becomes available and supporting REACH are the preventive actions needed in the UK and elsewhere. The need to limit exposures to environmental and occupational carcinogens is urgent.”
The European Union’s Registration, Evaluation and Authorisation of Chemicals (REACH) draft law, which aims to protect public health and promote a non-toxic environment, has been the subject of protracted and polarised debate between those who advocate a public health approach and those that say it would place an uncompetitive burden on Europe’s chemical suppliers.
However, the approach has received strong support from the European Trade Union Confederation’s health and safety thinktank, HESA.
Its October 2005 report (37) said REACH would prevent tens of thousands of cases of occupational disease every year and would lead to savings running to billions over 10 years. REACH, which is scheduled to come into force in 2007, would apply to chemicals including all those recognised by the EU as causes of occupational cancer. The ETUC believes REACH would lead to substitution of some of the substances of greatest concern with less hazardous substances – including those covered by the EU-wide law on carcinogens (38), which on paper at least encourages substitution of carcinogenic substances with less hazardous alternatives.
If all carcinogen use in the workplace stopped today, there would still be a working generation and hundreds of thousands of retired workers that have already faced some level of risk. For this reason, public health advocates are also arguing for more effective recording of exposures and better recognition of the link between work and health.
“We should be filing compensation cases to get recognition of the links between jobs and cancer and unions should be documenting cases of illness among their members and looking for trends,” says Dr Jim Brophy. “The health service should improve its act too, and should be documenting occupational histories – if they can document a person’s smoking and lifestyle habits, why not the workplace risk factors too?”
Prevent Cancer Coalition work and cancer webpages
Hazards tools webpage for assessing workplace risks.
Canadian Labour Congress prevent
Bladder Cancer Amicus-GPM information and advice on the links between bladder cancer and printing.
Report on Carcinogens, Eleventh Edition. US National Institute of Environmental Health Sciences/National Toxicology Programme, 2005.
2. National Statistics. Cancer:
1 in 3 develop cancer during their lives Website accessed
20 October 2005
asbestos statistics webpages. Website accessed 20 October 2005.
8. HSE mesothelioma statistics webpages. Website accessed 20 October 2005.
9. Bridbord K and others. Estimates of the fraction
of cancer in the United States related to occupational factors. Bethesda,
MD: National Cancer Institute, National Institute of Environmental Health
Sciences, and National Institute for Occupational Safety and Health, 1978.
11. Richard Clapp, Genevieve Howe, Molly Jacobs Lefevre. Environmental and cccupational causes of cancer: A review of recent Scientific literature. Lowell Center for Sustainable Production, University of Massachusetts Lowell, September 2005. Executive summary • Full report [pdf]
12. Landrigan PJ, Baker DB. Clinical recognition
of occupational and environmental disease. Mt Sinai Journal of Medicine,
volume 62, number 5, pages 406-411, 1995.
13. Siemiatycki J, Richardson L, Straif K and others. Listing occupational carcinogens. Environmental Health Perspectives, volume 112, number 15, pages 1447-1459, 2004.
14. Zahm SH and Blair A. Occupational cancer among women: Where have we been and where are we going? American Journal of Industrial Medicine, volume 44, pages 565-575, 2003.
15. Cancer-gate. How to win the losing cancer war. Epstein S. ISBN 0-89503-354-2, Baywood Publishing Company Inc, USA, 2005.
16. HSE metalworking fluids webpages
17. Darnton, A. J., McElvenny, D. M., Hodgson, J. T.
(2005) Estimating the number of asbestos related lung cancer deaths
in Great Britain from 1980-2000, Annals of Occupational Hygiene,
published online 26 August 2005 [abstract].
19. Johannes Guo, Timo Kauppinen and others. Risk of esophageal, ovarian, testicular, kidney and bladder cancers and leukemia among Finnish workers exposed to diesel or gasoline engine exhaust, International Journal of Cancer, volume 111, issue 2, pages 286-292, 2004 [abstract].
20. Carlos H. Barcenas, George L. Delclos, Randa El-Zein, Guillermo Tortolero-Luna, Lawrence W. Whitehead, Margaret R. Spitz. Wood dust exposure and the association with lung cancer risk. Am J Ind Med. 2005: 47: 349-57 [abstract]
21. Department of Health’s Committee on Carcinogenicity report, December 2004.
22. Becher H and others. Occupation, exposure to polycyclic aromatic hydrocarbons and laryngeal cancer risk, International Journal of Cancer, volume 116, issue 3, pages 451-457, September 2005 [abstract]
23. Lee WJ, Blair A and others. Cancer incidence among pesticide applicators exposed to chlorpyrifos in the Agricultural Health Study, Journal of the National Cancer Institute, volume 96, pages 1781-1789, 2004 [abstract].
24. Navas-Acien A, Pollan M, Gustavsson P, Plato N.
Occupation, exposure to chemicals and risk of gliomas and meningiomas
in Sweden. American Journal of Industrial Medicine, volume 42, number
3, pages 214-227, 2002.
26. Krishnan G, Felini M, Carozza SE, Miike R, Chew T, Wrensch M. Occupation and adult gliomas in the San Francisco Bay Area. Journal of Occupational and Environmental Medicine, volume 45, number 6, pages 639-647, 2003.
27. Burden of occupational cancer in Great Britain. Summary report of workshop held on the 22nd and 23rd November 2004 in Manchester, Health and Safety Laboratory, HSL/2005/33, 2005 [pdf].
29. Les expositions aux produits cancerogenes, Premiere Syntheses Informations, DARES, No.28.1, 2005. [pdf]
30. Kauppinen T and others. Occupational exposure
to carcinogens in the European Union. Occupational and Environmental
Medicine, volume 57, pages 10-18, 2000.
31. Huff J. IARC monographs, industry influence, and upgrading, downgrading, and under-grading chemicals: A personal viewpoint. International Journal of Occupational and Environmental Health, volume 8, number 3, pages 249-270, 2002.
32. Tomatis L. Identification of carcinogenic agents and primary prevention of cancer. Presentation to Collegium Ramazzini conference, Bologna, Italy, 20 September 2005.
33. Infante P. Cancer and blue-collar workers: Who cares? New Solutions, volume 5, number 2, 1995.
34. Vineis P and Simonato L. Proportion of lung and bladder cancers in males resulting from occupation: a systematic approach. Archives of Environmental Health, volume 46, pages 6-15, 1991.
35. Treasure T, Waller D, Swift S and Peto J. Editorial.
Radical surgery for mesothelioma. The epidemic is still to peak and we
need more research to manage it. British Medical Journal, volume
328, pages 237-238, 2004.
37. Pickvance S, Karnon J, Peters J and El-Arifi K.
Further assessment of the impact of REACH on occupational health with
a focus on skin and respiratory diseases, Final report. European
Trade Union Institute
39. The stop cancer before it starts campaign: How to win the losing war against cancer, Cancer Prevention Campaign, February 2003. [pdf]
40. Asbestos: Think again Environmental Working Group. Online report. 4 March 2004.
41. Gennaro V and Tomatis L. Business bias: How epidemiologic studies may underestimate or fail to detect increased risks of cancer and other diseases. International Journal of Occupational and Environmental Health, volume II, number 4, pages 356-359, October-December 2005 [pdf].
42. Rankin Bohme S, Zorabedian J, Egilman
D. Maximising profit and endangering health: Corporate strategies
to avoid litigation and regulation. International Journal of Occupational
and Environmental Health, volume II, number 4, pages 338-348, October-December
HAZARDS MAGAZINE WORKERS' HEALTH INTERNATIONAL NEWS