Methods and data needs to assess health impacts of chemicals in industrial contaminated sites.

BACKGROUND: human exposure to mixtures of chemicals of toxicological interest, typically found in industrial contaminated sites (ICSs), has been associated with a broad range of different health outcomes. Deprived population groups endure most of the burden of disease and premature death associated to the exposure to those pollutants. Characterising the impacts on health of an ICS is a challenging process. Currently the two main methodological approaches used are Human Health Risk Assessment (HHRA) and Environmental Epidemiological (EE) studies. OBJECTIVES: review existing guidance and scientific evidence for HHRA and EE studies applied to contaminated sites that orientate in selecting the most suitable methodological approach for characterising health impacts in ICSs according to the site characteristics, and the availability of environmental, health and sociodemographic data. RESULTS: HHRA has evolved into a more holistic approach, placing more emphasis in planning, community involvement and adapting the dimension of the assessment to the problem formulation and to the availability of resources. Many different HHRA guidelines for contaminated sites has been published worldwide, and although they share a similar framework, the scientific evidence used for deriving reference values and the variet of policy options can result in a wide variability of health risk estimates. This paper condenses different options with the recommendations to use those tools, default values for environmental and exposure levels and toxicological reference values that most suit to the population and characteristics of the ICSs under evaluation. CONCLUSIONS: the suitability to use one or another approach to assess the impact of ICSs on health depends on the availability of data, cost-benefit aspects and the kind of problem that needs to be answered. Risk assessment based on toxicological data can be very rapid and cheap, providing direct information when the intervention to protect the health of population is urgent and no suitable dose-response functions are available from epidemiological studies. Conducting EE studies provide a deeper insight into the problem of the exposure to industrial pollutants that do not require extrapolation from data obtained from toxicological studies or other population, addressing the community concern's more directly. Complementing the results obtained from different approaches, including those from public health surveillance systems, might provide an efficient and complete response to the impact of ICSs.