David Michaels

Manufactured Uncertainty Protecting Public Health in the Age of Contested Science and Product Defense

Abstract:  The strategy of “manufacturing uncertainty” has been used with great success by polluters and manufacturers of dangerous products to oppose public health and environmental regulation. This strategy entails questioning the validity of scientific evidence on which the regulation is based. While this approach is most identified with the tobacco industry, it has been used by producers of asbestos, benzene, beryllium, chromium, diesel exhaust, lead, plastics, and other hazardous products to avoid environmental and occupational health regulation. It is also central to the debate on global warming. The approach is now so common that it is unusual for the science not to be challenged by an industry facing regulation. Manufacturing uncertainty has become a business in itself; numerous technical consulting firms provide a service often called “product defense” or “litigation support.” As these names imply, the usual objective of these activities is not to generate knowledge to protect public health but to protect a corporation whose products are alleged to have toxic properties. Evidence in the scientific literature of the funding effect—the close correlation between the results of a study desired by a studys funder and the reported results of that study—suggests that the financial interest of a studys sponsors should be taken into account when considering the studys findings. Similarly, the interpretation of data by scientists with financial conflicts should be seen in this light. Manufacturing uncertainty is antithetical to the public health principle that decisions be made using the best evidence currently available.

Scientific Evidence and Public Policy

This collection of papers, published in the American Journal of Public Health (Vol. 95, p. S1-S150, 2005) is the product of a symposium on Scientific Evidence and Public Policy convened March 2003 by the Project on Scientific Knowledge and Public Policy (SKAPP) in Coronado, California. In June 1993, the US Supreme Court ordered federal trial judges to become gatekeepers of scientific testimony. Under Daubert and two related rulings, trial judges are now required to evaluate whether any expert testimony is both relevant and reliable. What began as a well-intentioned attempt to improve the quality of evidentiary science has had troubling consequences. The symposium provided a forum for scientists, philosophers and science studies scholars to have a dialog with legal scholars and federal judges about Dauberts philosophical underpinnings and impacts, and on the use (and misuse) of science in the legal and regulatory arenas. The Coronado Conference papers provide an important assessment of Daubert. Science is more subtle and less rigid than Daubert characterizes it. Whether applied in the courts or by regulatory bodies, Dauberts demand for scientific certainty runs counter to the workings of science, as well as to the basic principle that policy decisions should be made with the best evidence currently available.

Economic development and occupational health in Latin America: new directions for public health in less developed countries.

Occupational Health is increasingly recognized as an area of importance in Latin American public health. In the agricultural sector of the region, the concentration of arable land into large holdings devoted to the production of export crops has resulted in the formation of a large migrant work force and greatly increased use of pesticides. The manufacturing sector of Latin America has grown rapidly in size and importance. Throughout the continent, increasing numbers of workers are employed in high-hazard industrial jobs. Limited studies of occupational disease in agriculture, mining, and manufacturing suggest that there is a high prevalence of work-related illness in the populations at risk. Trade unions are generally weak, and the high rate of unemployment and underemployment render occupational health a low priority for many workers. Engineering controls and personal protective equipment are unknown or inadequate in many industries, and there is a shortage of trained occupational health professionals in the region. Steps are being taken by many Latin American governments to begin to address this problem. Needed are: increased worker and professional training; a uniform set of exposure standards; control of multinational marketing and usage of hazardous substances; the development of technical equipment appropriate for local use and increased research on occupational exposure in populations in less developed countries.

Change in Prevalence of Asbestos-Related Disease Among Sheet Metal Workers 1986 to 2004

In 1985, the Sheet Metal Workers International Association and the Sheet Metal and Air Conditioning National Association formed The Sheet Metal Occupational Health Institute Trust to examine the health hazards of the sheet metal industry in the United States and Canada. Between 1986 and 2004, 18,211 individuals were examined. The mean age of this cohort was 57.9 years, and the participants had worked for a mean (+/- SD) duration of 32.9 +/- 6 years in the sheet metal trade. Twenty-three percent of participants were current smokers, 49% were former smokers, and 28% were never-smokers. A total of 9.6% of participants (1,745 participants) had findings that were consistent with parenchymal disease (International Labor Organization [ILO] score, >/= 1/0); 60% of those with an ILO score >/= 1/0 were classified as 1/0, 34% as 1/1 to 1/2, and 6% as >/= 2/1. A total of 21% of participants (3,827 participants) had pleural scarring. There was a lower prevalence of nonmalignant asbestos-related disease among those who began to work after 1970, when compared to workers who began to work before 1949; those who began to work between 1950 and 1969 had a prevalence between the other two groups. The strongest predictor of both parenchymal and pleural disease on a chest radiograph was the calendar year in which the worker began sheet metal work; work in a shipyard was also an important risk. The results of this study suggest that the efforts to reduce asbestos exposure in the 1980s through strengthened Occupational Safety and Health Administration regulation have had a positive public health impact.

Mercury Poisoning in Nicaragua a Case Study of the Export of Environmental and Occupational Health Hazards by a Multinational Corporation

Pennwalt Inc., a multinational chemical and pharmaceutical firm based in the United States, operates a chloralkali plant in Managua, Nicaragua. This plant utilizes elemental mercury in the production of chlorine and caustic soda for markets throughout Central America. The plant was recently found to be contaminating the waters of Lake Managua (on which the plant is located) with 2 to 4 tons of inorganic mercury effluent per year-over 40 tons in the 13-year history of the plant. Examination of the 152 workers employed in the plant showed that 56 (37 percent) were suffering symptoms and signs of mercury poisoning, including tremors (in 45), memory and attention deficits (in 45), and paresthesias (in 52). Levels of airborne mercury vapor in the plant were found to range as high as 600 μg/m3. (The airborne standard set by the U.S. Occupational Safety and Health Administration is 100 μg/m3.) Workers in the plant had never been alerted to the hazards of mercury. The plant was found to be in deteriorated condition, with no recent investments in maintenance or modern safety equipment. It is reported that the parent corporation, Pennwalt, has been withdrawing capital from the operation (and from Nicaragua) since the fall of the Somoza regime.

Anergy compromises screening for tuberculosis in high-risk populations

Anergy may occur in groups at high risk for tuberculosis, compromising tuberculin skin testing. Within New York Citys correctional system, anergy prevalence was 25% among opiate users referred to detoxification programs and 3% in the general population. Correlates of anergy were recent weight loss and needle sharing. The high prevalence of anergy among opiate users compromises the utility of tuberculosis screening and suggests the need for routine chest x-rays to detect pulmonary tuberculosis in some high-risk-populations.

Asbestos disease screening by non-specialists: results of an evaluation

We performed a medical audit of an asbestos disease screening program offered to New York City sheet metal workers by a corporate medical service. The screening program purported to evaluate the health status of workers exposed to asbestos in the past and present during construction and renovation of commercial buildings. Using current Occupational Safety and Health Administration (OSHA) regulations as a benchmark, medical records for more than 800 workers who took the examination between 1982-83 were reviewed; x-ray interpretations of the staff radiologist were compared with the interpretations of specialists in occupational lung diseases. The audit found inadequate record-keeping procedures, a lack of a comprehensive occupational history, poor notification and absence of any form of health education. Further, there was an extreme lack of concordance between the staff radiologist and the specialist readers in the interpretation of x-rays (kappa = .14 for pleural disease and .26 for asbestosis). To an increasing extent, occupational clinical services are being provided by corporate medical groups; such groups may not be familiar with occupational health problems.

Addressing conflict in strategic literature reviews: disclosure is not enough

The success of the tobacco industry’s multi-decade campaign to delay regulation by manufacturing uncertainty about the studies linking cigarette smoking to lung cancer and other diseases is well documented.1 2 A less well-known consequence of this campaign is the appearance of a new, lucrative application of scientific expertise: product defence. Consulting firms working for producers of toxic chemicals are using the same approaches, and even the same scientists, that the tobacco industry relied on to forestall regulation of cigarettes. Today, these firms aim to impede public health regulation by questioning studies that have identified hazardous properties of asbestos, beryllium, chromium, lead and a host of other toxic chemicals.3 Defending hazardous chemicals has become lucrative business. It is increasingly common for scientific studies to be commissioned in order to be deployed in regulatory or legal proceedings. Companies involved in the welding industry paid more than US

Exposure of sheet-metal workers to asbestos during the construction and renovation of commercial buildings in New York City. A case study in social medicine.

12 million to scientists who published papers disputing the link between welding-related manganese exposure and neurological disease.4 Similarly, two product defence firms working for defendants who produced asbestos brake shoes or related friction products received over US

Review of the OSHA-NIOSH Response to the Deepwater Horizon Oil Spill: Protecting the Health and Safety of Cleanup Workers.

23 million for their services, billing hundreds of dollars an hour to write papers for peer-reviewed journals.5 Publication by paid experts is not limited to scientists employed by polluters and manufacturers of toxic materials. Of the 26 papers published by US authors between 2002 and 2006 on the risk …