A call to action: epidemiologists assert themselves with scientific data

A broad range of epidemiology organizations came together for the first time to clearly state that all forms of asbestos are harmful and causally related to disease and death.i The Position Statement on Asbestos¹ from the Joint Policy Committee of the Societies of Epidemiology^2,3 (JPC-SE) was released on July 24, 2012. The Statement has rapidly garnered worldwide support.ii It calls, without any equivocation, for all mining, trade, and use of asbestos to cease. How did this come about? What does it portend for the future with respect to a role for epidemiologists in policy matters?

Epidemiologists understand and practice the science that underlies public health and clinical medicine. Epidemiology is sometimes belittled as ‘never proving anything.’ An assault on the field by Gary Taubes⁴ was highly publicized.iii One factor in public skepticism about epidemiology comes when there are apparently discrepant findings between epidemiologic studies or between observational studies and randomized trials. The JPC-SE Statement explains that the JPC-SE has concluded that with respect to all forms of asbestos, credible study results consistently show risk for disease and premature death.

Routinely, epidemiologists thoroughly assess any weaknesses in study designs and marshal caution with respect to the conclusions and recommendations proffered. Increasingly in medicine and public health, a systems approach has been espoused to better capture at earlier junctures the many direct and indirect effects to better protect public health through earlier interventions.^5,6 Thoughtful vigilance is requisite to anticipate and avoid long-term detrimental effects and to promote enduring changes.⁷

Systems thinking utilizes a framework for seeing interrelationships and patterns of change, rather than snapshots. This framework helps to identify areas where key data are required to formulate clear recommendations. Sometimes such information is not yet available to complete the picture. At other times, it is clear that the nuances of incremental data will not be likely to materially affect the conclusions. Systems thinking approaches also require the consideration of long-term horizons. Epidemiologists demand an array of knowledge gleaned from multiple independent studies and settings, from multiple approaches and study designs, and from multiple disciplines (such as industrial hygiene, toxicology, sociology, biology, molecular biology, immunology, and pathology), and careful assessment of the biases (direction and magnitude, and likelihood that they could account for the observations) before accepting relationships as causal.

In the development of the Position Statement on Asbestos, several sets of expert epidemiologists painstakingly examined the data, relying quite heavily also on the recent International Agency for Research on Cancer (IARC) evaluation (2012).⁸ After a rigorous process requiring each society to review the statement as per its respective internal procedures, nine societies agreed to endorse a very clear Statement that addresses controversial issues head-on. The public, the media, and governments need to understand: there is no credible counterpoint. In summary, this Statement presents an example where a durable consensus was reached among the historically conservative profession of epidemiologists. Supposed controversy, as noted by the Statement, was fomented by some ‘junk science,’ funded by the asbestos industry and their paid consultants, that contaminated the asbestos literature.⁹

The JPC-SE, as an organization, was formed in 2006. It initially addressed issues of common concern to epidemiologists such as regulatory limitations on beneficial research, as well as the absence of full-fledged epidemiologists from a number of important health and medical research panels.

This occurred in a context where there has been a widespread perception among scientists that societal policies are often pursued and implemented without due attention to the facts, and with undue influence from personal beliefs, business interests, and/or narrow or short-term considerations.⁷ This impression exists in many different countries with respect to an increasing variety of issues and settings. Growing concerns about these and other matters over the last two decades among epidemiologists helped in providing the impetus for the formation of the JPC-SE.

Economists know that the marketplace does not always function optimally. In economics, an externality is a cost or benefit incurred by a party not involved in the transaction causing the cost or benefit, the value of which is not included in prices. With a negative externality, such as pollution, there are external costs. With a positive externality, such as occurs with education, there is an external benefit. With either type of externality, prices in a competitive market do not reflect the full costs or benefits of producing or consuming a product or service. When an externality exists, the economic costs or benefits are incompletely measured by markets. For example, companies do not have to subtract these external costs from their revenues, leading to inefficiencies in the allocation of resources. These concepts underlie our under-consumption of prevention services, where when properly allocated each dollar spent may prevent several multiples of that from being spent on future medical care (another example of a positive externality).⁷

Because neither the market nor private individuals can be counted on to prevent these inefficiencies in the economy, the government must intervene with regulation and oversight. Sometimes, the harms are not immediately recognized (as has occurred with many carcinogens and pollutants) or occur only many years later. Furthermore, they may accumulate for decades before remedial actions are taken, often at considerable cost. After the externality is recognized, regulations along with enforcement are frequently needed. But even strong legislation will be undermined unless monitoring (that assesses compliance) and enforcement are both adequately and continuously funded and deployed. An interdisciplinary viewpoint is essential when monitoring policy implementation.⁷

Protection of workers and the public from harmful substances is a classic example of the need for intervention. When adverse outcomes are delayed in time, perhaps by years or decades, as seen with asbestos, and perhaps exacerbated by delayed recognition, it becomes even more difficult for externalities to be captured by the marketplace, even with the promulgation of regulation or taxes. Although litigation in the pursuit of justice does not solve such problems, its existence and its threats also may alter the economic calculus. The economic models incorporating externalities underlie a portion of the systems thinking approach.

With the current Position Statement, a new leaf has been turned. The Statement recognizes that epidemiologists and other relevant experts had reached a broad consensus about the harms of asbestos, but that this consensus was being ignored by policy makers in some countries, and that some of the populations being affected remain largely ignorant of the dangers. Both the public and policy-makers have often been misled by powerful asbestos interests. Epidemiologists have accumulated the data on the harms of asbestos the hard, but standard way — through the steady, careful, but cold and dispassionate accumulation of morbidity and mortality data from a vast array of studies representing a variety of epidemiologic approaches, from case reports and case series signifying sentinel events, to observational study designs.

The initial process by the JPC-SE entailed a careful review of many credible studies and reviews concerning asbestos, including apparently definitive declarations by well-reputed, impartial bodies such as that by the World Health Organization in 2006¹⁰ and its affiliate organization, the IARC, in 2012.⁸ With the recognition by the JPC-SE that the asbestos industry questioned the association of disease with some forms of asbestos, a careful examination of these contrary claims was undertaken to ascertain what, if any, validity there might be in them. The effort was assisted by published academic studies that had examined some claims such as that by Egilman et al,¹¹ as well as other public data that helped to clarify the evolution of such claims.

It was also noted how the tobacco industry had successfully countered for many years the consensus among scientists and epidemiologists about the harms of various tobacco products,^9,12 providing an effective model for other industries to follow. Economic issues were raised, and considered from a systems approach.

The Statement further urges societies of epidemiology and public health organizations and agencies, particularly in those countries that continue to mine, use and/or export/import asbestos, to adopt a position calling for a ban on the mining, trade, use, and export of all forms of asbestos and to support scientists who are subjected to tactics of intimidation to stop them from speaking up about the threat to health posed by asbestos.

The latest figures show that 64% of asbestos sold in 2011 went to Asian countries, where there is virtually no collection of data on asbestos-related diseases and deaths. Two countries alone – China and India – represent 46% of 2011 global asbestos consumption. Monitoring of asbestos-related diseases has been virtually non-existent in these two countries.

The Statement is strengthened by the new information about asbestos in China published in this issue,^13,14 which is at once consistent with the thesis of, and similar to data in, the JPC-SE Statement, and which extends those data. These articles further support the concerns posed by the JPC-SE.

Wang et al.¹³ reinforce and amplify in this issue, with their multiple figures and tables, the asbestos mining and usage data presented in the JPC-SE Position Paper.¹ China in particular has exhibited skyrocketing usage (Figure 1¹³) concomitant with its rapid industrialization and its ready availability due to internal, massive reserves of asbestos.¹³ Substitutes have been developed for the many traditional uses of asbestos, with minimal current use in Western countries such as the United States and Canada. Regrettably, the asbestos industry has succeeded in maintaining global asbestos production at approximately 2 million metric tonnes (Mt) per annum,¹ with China having risen to stand second in the pack, behind Russia. Wang also summarizes critical data on asbestos-related diseases within China.

Dr. Frank notes in his editorial in this issue¹⁴ that it can be relatively easy [for some to try] ‘to deny that there is much of a problem when there are few statistics to elucidate the difficulties being suffered by workers in these countries.’ The careful documentation by Wang¹³ about usage patterns provides valuable information about China. Dr. Frank has affirmed ‘there is every reason to believe…’ asbestos exposure in China will continue to cause disease. Taking that argument a step further, the JPC-SE in its Position Statement has declared that it is time to stop pulling punches, that the epidemiologic data are overwhelming in demonstrating that the use of asbestos will lead to an epidemic of disease,¹ and that it is unnecessary to await the future accumulation of yet more data about forthcoming disease before calling for action to avert harm. The JPC-SE is calling for action now, based on the body of solid epidemiologic evidence, in order to prevent further asbestos-related epidemics. Frank rightly notes, ‘the absence of data does not mean the absence of disease.’ Indeed, commercial or government interests may seek to avoid the collection of those very data to conceal emerging epidemics and other problems (representing forms of ‘suppression bias’ and ‘repression bias’¹⁵).

The Position Statement on Asbestos¹ is aimed at audiences that may not have ready access to academic journals. Thus, an effort was made to make the sources underlying the report readily accessible to readers. Whenever possible, publicly accessible sources on the Internet are provided, contributing to informing policy at two levels: the public as well as government. To further extend accessibility, all material was released in both English and French at the outset. The full text is available in Portuguese, and the Executive Summary and media release are being translated into Chinese, Russian and other languages. All translations are being posted on www.jpc-se.org/position.htm as they are developed, utilizing a certified translator whose translation has then been reviewed by an epidemiologist prior to release. (However, the final reference version will always remain the English – British style – version.) The industry will, in turn, I hope, realize that its deceptive practices need to cease. And the media should recognize and understand that there is no viable controversy, with the source materials readily available for them to consult as needed.

There is a growing need for international collaboration in epidemiology, to synthesize what we know. Since our work is directed to informing policy, our syntheses must be packaged and placed at the disposal of decision-makers. Within days of the publication of the asbestos Statement, the Brazilian Association of Public Health (ABRASCO) joined the JPC-SE. The JPC-SE looks forward to other sister societies with epidemiologists around the world joining its ranks; the application mechanism is summarized at http://www.jpc-se.org/about.htm.

Events in the United States or in other countries sometimes highlight evolving problems globally – such as recent cutbacks in census data collection in several countries and even the potential elimination of agencies, such as the U.S. Agency for Healthcare Research and Quality (AHRQ). The AHRQ serves as a critical collector and analyzer of data. (The primary mission of the AHRQ is ‘to improve the quality, safety, efficiency and effectiveness of healthcare for Americans.’¹⁶ It promotes evidence-based medicine and public health in the U.S., and its reports have had considerable international impact.) The JPC-SE may well develop position statements on such issues, since it recognizes that policy-makers should neither avoid facing the facts nor prevent their collection. The JPC-SE works on the topics that the member organizations of the JPC-SE together choose to set as priorities.

The focus of the JPC-SE is set by its member societies, through monthly conference calls supplemented by continual communications. With its increasingly global membership as well as a publicly available website to help in the dissemination of its findings at www.jpc-se.org, I anticipate that the JPC-SE will continue its efforts to pinpoint topics of importance throughout the world. I hope and trust that there is value in these joint assessments by epidemiologists. I can only echo the hope that the public, industry and governments will pay due attention to scientists working in the public interest, with their data and caveats; and, I hope that our scientists pay due attention to a systems approach when constructing and providing advice.

Disclosures: The author declares no conflicts of interest.

Notes

i See the Introduction as well as the endorsing organizations listed in Appendix A of the Statement.

ii See Appendix B, which lists formal endorsements from outside organizations (included below) and the Appendix C endorsements from individuals (not included herewith), both of which are being periodically updated online at the JPC-SE website www.jpc-se.org

iii Criticisms have been leveled at Taubes, such as his relying on out-of-context quotes and other journalistic devices to feed public misperceptions about epidemiology.