The Lancet, Volume 381, Issue 9864, Pages 359 - 361, 2 February 2013 http://www.thelancet.com/
journals/lancet/article/ PIIS0140-6736%2813%2960152-X/ fulltext
Alleged links between the International Agency for Research on Cancer (IARC) and the asbestos industry have been condemned on the eve of a crucial UN conference. David Holmes reports.
Does asbestos corrupt more than just DNA? That is the question now being asked of the International Agency for Research on Cancer (IARC) after a series of recent decisions triggered a storm of protest from governments, non-governmental organisations, and health campaigners and left the agency, which is an arm of WHO, open to accusations that range from the relatively benign charge of poor judgment to allegations of corporate capture by the asbestos industry.
The row erupted late last year, when IARC accepted an invitation to send one of its scientists, Valerie McCormack, to present data at a conference in Kiev, Ukraine, entitled Chrysotile Asbestos: Risk Assessment and Management (panel 1). That decision sparked a flurry of emails and letters to the Director-General of IARC Christopher Wild, including one seen by The Lancet from the Italian Minister of Health Renato Balduzzi, on behalf of the Italian Government, imploring IARC to shun the conference over suspicions that the organisers were in cahoots with the Russian asbestos industry.
Panel 1: Asbestos 101
The term asbestos comes from the ancient Greek word meaning inextinguishable, and is used today to describe a group of six related silicate minerals that are divided into two types on the basis of their fibre morphology. Chrysotile, also known as white asbestos, is the sole representative of the serpentine type; so called because of the twisted appearance of its microscopic fibres. The second type, the amphiboles, all have straight, needle-like fibres, and this type accounts for the remaining five minerals: amosite (brown asbestos), crocidolite (blue asbestos), and the more rarely occurring tremolite, anthophyllite, and actinolite.
Chrysotile asbestos is the only type of asbestos still produced today, and accounts for more than 95% of all asbestos ever mined. All types of asbestos are classed as carcinogens by WHO's International Program on Chemical Safety, and an IARC working group of 27 scientists who met in 2009 came to the “fundamental conclusion” in The Lancet Oncology that “all forms of asbestos are ‘carcinogenic to humans’.” And in addition to the increased risk of lung cancer and mesothelioma associated with all forms of asbestos, the IARC scientists also concluded that “sufficient evidence is now available to show that asbestos also causes cancer of the larynx and of the ovary”.
The exact mechanism through which asbestos fibres cause cancer is unclear, but several mechanisms have been proposed, none of which are mutually exclusive. The oxidative stress theory turns on the inability of phagocytic cells to engulf asbestos fibres that become lodged in the lungs, leading the cells to produce large amounts of DNA-damaging free radicals as they try and fail to clear the fibres. Another theory is that asbestos fibres interfere with the process of cell division, and still another theory proposes that the fibres help to concentrate other toxic substances such as tobacco smoke to increase the risk of lung cancer.
Sources inside WHO tell The Lancet that in the days leading up to the meeting, high-ranking WHO officials urged IARC to cancel its attendance at the Kiev conference. A spokesperson for WHO's Director-General Margaret Chan declined to comment; however, speaking on behalf of IARC, Nicolas Gaudin denied that Margaret Chan nor any other senior WHO officials had tried to intervene, and continued that “IARC is not privy to possible discussions internal to WHO on this subject. Discussions at IARC focused on the importance of presenting the relevant science to the audience of the Kiev meeting and in ensuring with the organisers that we were not associated with the resolution emanating from the meeting. IARC did receive a number of emails requesting us not to participate in the meeting and our response was announced on our website.” Expanding on that response, Gaudin explained that the Kiev conference was seen as an “opportunity to emphasise the dangers related to the use of asbestos, in this particular case stressing to this audience that the often-overlooked lung cancer burden is in absolute numbers much larger than the mesothelioma burden. The same scientific presentation was given at the 2012 annual UICC meeting in Montreal and is based on a scientific paper led by IARC staff.”
That paper—Estimating the asbestos-related lung cancer burden from mesothelioma mortality—has been criticised for inaccurately downplaying the risks of asbestos, an over reliance on data from studies done in Quebec funded by the Canadian asbestos industry, and policy recommendations that failed to take into account WHO's recommendation to end all asbestos use. McCormack also ignored several requests seen by The Lancet to include updated figures pertaining to the mesothelioma risk posed by chrysotile compared with amosite and crocidolite in the data presented at the Kiev conference. Slide 6 of McCormack's presentation was a table based on a 2000 study by UK researchers John Hodgson and Andrew Darnton showing that chrysotile caused one case of mesothelioma for every 100 caused by amosite and 500 caused by crocidolite. In 2009, the same authors published a significant revision of these figures, with a new ratio of 1:10:50, but this new estimate was omitted from the IARC presentation.
IARC's invitation to the conference was issued by the Russian Scientific Research Institute of Occupational Health (SRIOH), who were the joint organisers of the Kiev conference. IARC's published response to the requests that it avoid the conference makes a passing reference to IARC's decision to collaborate with the SRIOH “on a study of cancer in chrysotile workers in Asbest, Russia”, the full title of which is: Historical cohort study of cancer mortality following exposure to chrysotile asbestos at the Uralasbest plant in Asbest, Russian Federation. The lead author on this paper is Evgeny Kovalevskiy, and it is IARC's decision to work with Kovalevskiy and the SRIOH in particular that has given rise to the gravest concerns within WHO, and the most vehement criticism from outside the organisation.
In a letter to IARC's Director-General Wild signed by Richard Lemen (retired US Assistant Surgeon General and adjunct professor at the Rollins School of Public Health, Emory University, Atlanta, GA, USA), Arthur Frank (Drexel University School of Public Health, Philadelphia, PA, USA), and Barry Castleman (author of Asbestos Medical and Legal Aspects), the authors argue that “Kovalevskiy is a leading promoter of use of chrysotile asbestos. He testified before the Supreme Court of Brazil in August 2012, as witness on behalf of the Brazilian Chrysotile Institute. He testified that there is no evidence whatsoever to justify banning the use of chrysotile asbestos; that he opposes placing chrysotile asbestos on the Rotterdam Convention's List of Hazardous Substances; that, in the past, harm to health was caused by the use of amphibole asbestos and excessive, prolonged exposure levels to chrysotile asbestos, but that, today, chrysotile asbestos is causing no harm to health in Russia. We consider that it is unacceptable that a scientist, who is a promoter of chrysotile asbestos use, should be a lead scientist on an IARC research project regarding chrysotile asbestos.”
The authors then go on to point out that several years ago, WHO Director-General Margaret Chan withdrew the SRIOH's designation as a WHO collaborating centre because of its “promotion of continued use of chrysotile asbestos and conflicts of interest endangering WHO's credibility”. According to IARC's Gaudin, “the request to consider the study first came to IARC from Russian scientists, who approached IARC shortly after the official signature of a Memorandum of Understanding between IARC and the Russian Federation in 2007”. The Lancet understands that the request was supported by the Russian member of IARC's Governing Council. 2007 was the year that the Russian Federation resumed financial contributions to IARC, including full payment of arrears, after what Gaudin terms “an interruption in assessed financial contributions” dating back to the early 1990s. However, Gaudin asserts that “the study on the quantitative cancer risks of chrysotile in Russia (in Asbest) was not discussed during the sessions of the Governing Council, and was not a condition of the resumption of participation [in IARC] or financial contributions by the Russian Federation”.
The timing of both IARC's attendance at the conference and the decision to collaborate with Kovalevskiy and the SRIOH is especially sensitive, coming as it does on the eve of the sixth meeting of the Conference of the Parties to the Rotterdam Convention, which will take place in April. Among other things, the conference will discuss the proposed listing of chrysotile asbestos in Annex III of the Convention (panel 2). All other forms of asbestos are already listed, and were chrysotile to be listed, exporters would need to obtain “prior informed consent” from importing states, and take steps to ensure that importing governments are able to assess adequately the risks posed by the chrysotile in a local context. It will be the fourth time that the listing of chrysotile has been considered and, as before, there is expected to be strong opposition from parties aligned with the asbestos industry.
Panel 2: The shifting burden of chrysotile
Asbestos minerals have been prized for centuries for their ability to withstand heat and mechanical and chemical damage, and were most widely used as additives in construction materials throughout the 20th century, particularly in the post-war construction boom in developed countries. However, mounting evidence of the carcinogenicity of asbestos led to the banning of amosite and crocidolite from the 1980s onwards in many developed economies, followed by bans on chrysotile throughout the 1990s and the early part of this century. Now, more than 50 countries ban the use of all forms of asbestos, including the entire European Union, and a de-facto ban exists in many other countries such as the USA and Canada. Almost all of the worldwide consumption of asbestos is now concentrated in developing economies. According to United States Geological Survey figures, just over two-thirds of the world's asbestos consumption is accounted for by the rapidly developing BRIC nations: China (30% of world consumption), India (15%), Russia (12%), and Brazil (9%).
Measuring the exact burden of disease caused by asbestos is notoriously difficult, in part because of the often long time lag between exposure and the onset of the disease, and in part because of problems with the diagnosis and coding of cases. As a result, most surveys are likely to underestimate the number of cases of asbestos-related disease. Nevertheless, WHO estimates that over 107 000 people die each year from asbestos-related lung cancer, mesothelioma, and asbestosis from occupational exposure alone, with the figure likely to be far higher once environmental exposures are taken into account. WHO also estimates that 125 million people in the world are still exposed to asbestos at the workplace, although the monitoring of the use of asbestos is almost non-existent in many of the countries that still allow its use.
The listing of chrysotile was first proposed in 2006, after a comprehensive review of evidence by the Rotterdam Convention's Chemical Review Committee (CRC), composed of 31 scientists nominated by various countries. At that time, Canada was one of the largest producers and exporters of chrysotile in the world, despite operating a de-facto ban on domestic usage, and was the largest producer with the power to veto the listing of chrysotile in Annex III; Russia was only an observer state at that time. The Canadian representative exercised the veto, with the support of Kyrgyzstan, Iran, India, Ukraine, and Peru, and chrysotile became the first and only substance to have been recommended for listing in Annex III by the Convention's CRC to be blocked by parties to the conference. It has remained in that state of limbo ever since.
At the most recent Conference of the Parties in 2011, the parties seemed on the cusp of consensus after Kazakhstan, Kyrgyzstan, Ukraine, India, and Vietnam (with Russia again an observer) reversed their initial opposition to the listing of chrysotile during the course of negotiations. But in a move widely condemned at the time, just as agreement was imminent, the Canadian delegation, which had until that point been silent, stood and declared that although they had no disagreement with the scientific case for listing chrysotile in Annex III, they would nevertheless oppose its listing. The Canadian party offered no justification for their opposition and the listing of chrysotile was again blocked, this time with Canada as the sole dissenting voice.
As of late 2012, Canada is no longer in the asbestos business, after the incoming Quebec Premier Pauline Marois cancelled a US$50 million government loan originally intended to reopen the Jeffrey asbestos mine, and pledged to put the money toward economic diversification in the area. As a direct result, Canada reversed its position and announced that it would no longer oppose the listing of chrysotile in Annex III. However, in 2013 Russia will, for the first time, have the power to veto chrysotile's listing, and campaigners argue that the Kiev conference and IARC collaboration are key planks in its ongoing strategy to legitimise its opposition to the listing.
“The Kiev conference came out of an initiative to destroy the Rotterdam Convention”, says Kathleen Ruff, a Canadian human rights campaigner and senior adviser to the Rideau Institute—an independent research and advocacy organisation based in Ottawa. “In 2011, those opposing the listing said they wanted a new conference to look at the ‘modern’ data to counteract the Chemical Review Committee's ruling. Kiev is the result. It is not a bona fide conference, it's a sham conference, a weapon to undermine the integrity of science, and it's about more than chrysotile now, it's about the gutting of a UN convention.” The consensus statement issued after the Kiev conference concludes that “in the light of data presented in the conference, participants of the conference are of the opinion that under the current circumstances, the issue of including (or not including) chrysotile in Annex III to the Rotterdam Convention is premature”. Although IARC is at pains to make it clear that it was not involved in the discussion of the resolution, and was not a signatory to it, the fact that IARC attended the conference lends it a “veneer of respectability”, says Ruff.
According to a WHO source who wished to remain anonymous, recent manoeuvres by the Russian asbestos industry are just the latest in a decades-long campaign to resist international pressure for tighter controls on asbestos, using tactics that owe a great deal to the tobacco industry. On WHO's fact sheet on asbestos, the organisation says that it recognises “the most efficient way to eliminate asbestos-related diseases is to stop the use of all types of asbestos”. And yet on the same page, it states that “with Resolution 60.26, the World Health Assembly requested WHO to carry out a global campaign for the elimination of asbestos-related diseases ‘…bearing in mind a differentiated approach to regulating its various forms—in line with the relevant international legal instruments and the latest evidence for effective interventions…’”. That final clause was inserted at the last minute, “without any previous international negotiation” after Russia and its allies threatened to block the whole resolution, the source says. In 2010, The Lancet reported in these pages on the Russian veto of a proposed asbestos ban at WHO's European region summit in Parma, Italy, where Russia also staged a last minute attempt to derail an agreement among all members to beef up European health and environment planning powers. Kovalevskiy was part of the Russian delegation at the time, and told The Lancet that “NGOs in the process might not be really non-governmental, but acting as stooges for some government”.
Full-size image (93K) Ria Novosti/Science Photo Library
A chrysotile asbestos quarry in Sverdlov, Russia