The PEC project
Analysis of health impacts associated with accidental release of chemicals from industrial sources is currently based on knowledge of inherent properties of individual agents (toxicity, flammability, explosivity, etc.) and the predictable response to a given dose of the chemical determined by classical health risk assessment methods. Limited information exists on health risks that may result from absorption of complex chemical mixtures or from combined accidents, natural and technological (NaTech), for example an earthquake or terroristic attack that devastates chemical installations causing environmental release and dispersion of toxic chemicals in the primary disaster area. A consolidated methodology for risk assessment of chemical mixtures and combined NaTech hazards is currently not available. In this project an integrated multi-hazard risk assessment toolkit will be developed and the validity of this model will be evaluated on a case study (Priolo Gargallo area, in Sicily – Italy) by considering the effects on plant structures and infrastructures of hypothetic natural and man-made disasters, such as earthquake, flood or terroristic attack leading to accidental release of large amounts of toxic chemicals into the environment. Immediate and long-term population health impacts of the toxic chemicals absorbed either individually or in combination will be determined and quantified according to characteristics (type and intensity) of the initial disaster, degree of vulnerability of buildings and infrastructures, quantity of chemicals stored/handled in the plants, magnitude of their dispersion into the environment and levels of chemical contamination in the disaster area. The key receptors considered in simulations will include employees present in the affected plants during the incident, emergency responders, and the local population. A risk prioritisation matrix based upon damage level attainable in the infrastructures and potential public health risks will be developed to provide strategic risk information for public health planning.
The project aims at implementing an integrated model for rapid multi-hazard health risk assessment applicable to chemical release incidents occurring during major natural or man-made disasters and developing a composite risk matrix, considering both severity and probability of identified hazards, to prioritize disaster-related public health risks from clusters of industrial facilities handling toxic chemicals. Specific objectives are: (a) to develop an operational approach toward the implementation of a model applicable to contamination and health risks assessment in connection to natural and man-made disasters (b) to estimate pathways, levels and time course of environmental contamination, human exposure profiles and health damage (acute and chronic) that may result, at various time intervals after a disaster, from acute or prolonged absorption of a mixture of model hazardous chemicals selected among those listed in the EU inventory of high-risk toxic industrial substances; (c) to develop a series of risk mitigation guidelines for characterisation of “multi-hazard and multi- event-related” health risks in chemical exposures following natural or man-made disasters, namely guidelines for early warning systems, risk mitigation of buildings and plants, population exposure, environmental and human health monitoring and proper design of post-disaster populations surveys; (d) to provide evacuation distance estimates based on acute chemical exposure indicators for different toxicant combinations, and different types of disasters and incidental release scenarios ; (e) to develop an integrated computational platform supported by a GIS system which covers the full chain from chemical releases to internal doses in human tissues in order to build a functional and ready-to-use software operated by local authorities responsible for civil safety and public health protection.
Expected results of the project include for Task A (DAPP, EUC) a well characterised model of hypothetical disaster in which the cascade of events caused by triggering hazards (earthquake, floods, or a terroristic attack) affecting two model chemical plants within the selected study area will be assessed. The selected area is Priolo Gargallo in Sicily, Itay. Specific results will be the models regarding the shaking for different return periods of the earthquake, attenuation law and faults properties to determine the impact of earthquakes, and dominant processes in floods hazard identification with realistic time series of water levels for a given probability of exceedance. Expected data from Task B (EUC, DELFT, DAPP) are those regarding fragility functions of different plant components; codes of the case study buildings and non-structural components; the vulnerability of components subjected to the effects of industrial accidents, and multi-hazard contamination risk maps. Work from Task C (AUTH) will provide data of concentration levels of chemicals and realistic risk zone maps corresponding to defined thresholds in the area surrounding the incident. From these data exposure profiles will be derived by multimedia modelling which in turn will feed physiology-based toxicokinetic (PBTK) models to estimate internal doses of chemicals in target tissues. The above modelling tool chain will be implemented in a user-friendly ready-to-use software. The exposure data will be used to determine acute health impacts in the affected population and to predict chronic (carcinogenic and non-carcinogenic) effects for both individual chemicals and their combination according to classical health risk assessment procedures (Task D). An integrated health risk prioritisation matrix will then be developed based on the results obtained from Tasks A-C. From the incident simulations a series of guidelines based on cost/benefit analysis will be generated (Task E) addressing measures for risk mitigation of structures (buildings and plants, DAPP), mitigation of population exposure to the incident-related chemicals (AUTH), and mitigation/prevention of health risks (EUC). Recommendations for the reproducibility and field application of the proposed methodology will be included in the guidelines. Results obtained from this complementary work (NaTech-Biol-Med) are expected to provide a novel valuable tool complementing current prevention practices in the area of natural and man-made disasters.