"Arsenic in rice is not a problem because everybody eats it": The past, present and future of regulation of arsenic in drinking water and food

Despite its place as the most serious geogenic environmental chemical hazard, regulation of arsenic in water and food, derived directly or indirectly from high arsenic groundwaters or soils, (i) varies across the globe, (ii) is highly variable (in terms of equivalence of modelled health risks) across exposure routes considered and (iii) is not as demonstrably protective of public health as are the regulations for many if not most other environmental chemical hazards. This reflects in part (i) uncertainties in dose-response relationships, particularly at low exposures for sequela for which arsenic is a contributory factor; (ii) concerns over the costs, both economic and political, of regulation; and (iii) implicit and explicit disquiet over the use of willingness-to-pay or other objective economic criteria, which ultimately are predicated on placing differential values on the lives of different individuals. Citizen participatory approaches provide a potential basis for using multi-criteria analysis for establishing locally/regionally appropriate regulatory values. Scientists and economists, amongst others, have a critical role in supporting such activities, particularly through clear communication of ideas, information and uncertainties.