The asbestos paradox: global gaps in the translational science of disease prevention

Mesothelioma, a malignant cancer of the pleura, is almost exclusively associated with asbestos exposure.1 What will it take to eradicate this highly preventable cancer? Despite the scientific consensus that exposure to asbestos fibres causes deadly diseases, we continue to use asbestos in products designed ostensibly to improve quality of life. For example, asbestos is still used in automobile brake-linings, and in the chloralkali industry that produces chlorine for disinfecting water worldwide.2 Toxic asbestos remains the main material for some plastics and in domestic building products – especially in corrugated roof materials for housing in developing countries. Regional disparities persist in translating scientific knowledge of asbestos risks to policy for preventing cancers and other diseases. Most cases of mesothelioma are now found in countries producing asbestos and in developing countries using the products, where scientific knowledge of asbestos toxicity seems to have been lost in translation.3 It is in these countries, where affected populations are less likely to have access to prompt diagnosis, health care or litigation, that we will observe the next wave of mesothelioma cases.3 A perspective on three scientific translational gaps is presented here: (i) making policy decisions within the context of scientific uncertainty, (ii) the role of alternative assessments in selecting safer commercial materials, and (iii) the translation of scientific evidence into disease prevention. The International Labour Organization’s Asbestos Convention, designed to protect workers from the well-known hazards of asbestos exposure, entered into force on 16 June 1989. Yet, nearly twenty-five years later, only 35 countries, 19% of 184 that are eligible, have formally ratified the Convention.2 In contrast, 154 countries (83% of those eligible) are Parties to the 1998 Rotterdam Convention on the Prior Informed Consent Procedure for Certain Hazardous Chemicals and Pesticides in International Trade.4 However, attempts to include chrysotile asbestos – the most common form used – in Annex III of the Rotterdam Convention have failed repeatedly, most recently at the sixth Conference of Parties due to resistance from seven countries, most of whom continue to produce, use, and export asbestos on a large scale (Fig. 1). The minority objection prevailed despite powerful testimony from the representative of the World Health Organization (WHO) that chrysotile and all forms of asbestos are carcinogenic to humans.6 Moreover, given the widespread use of chrysotile in domestic building products, it is impossible to safeguard hazardous exposures in occupational settings or to prevent environmental contamination that threatens the general population. Opposition to the proposal to regulate chrysotile asbestos under the Rotterdam Convention highlights three major gaps in the translation of scientific evidence to global disease prevention policy. The asbestos paradox: global gaps in the translational science of disease prevention Oladele A Ogunseitan