Health risk analysis for emissions to air from CO2 Technology Centre Mongstad

•CO2 Technology Centre Mongstad is a facility for testing and improving CO2 capture technologies.•A health risk analysis for the emissions to air from TCM's amine unit has been executed.•The highest risk was assessed to be the exposure of the population to nitrosamines and nitramines.•TCM's conclusion was that the risk was acceptable.•The Norwegian Climate and Pollution Agency granted TCM a permit in November 2011. A health risk analysis for the emissions to air from the CO2 Technology Centre Mongstad (TCM) has been executed. TCM is the world's largest facility for testing and improving technologies for CO2 capture, and is located at the West coast of Norway. The risk analysis was an important fundament for the application for an emission permit for the amine based post-combustion CO2 capture unit. The highest risk was assessed to be the exposure of the population to uncertain concentrations of nitrosamines and nitramines in air and drinking water. Nitrosamines and nitramines are groups of possible degradation products formed from amines. The components within these two groups have variable degrees of carcinogenicity. Nitrosamines are formed from amines in the CO2 capture process and in the atmosphere, while nitramines are assumed to form only in the atmosphere. The risk was analyzed by comparing the sum of concentrations of nitrosamines and nitramines in air and fresh water with recently available guidelines. The concentrations were obtained by modelling atmospheric chemistry, dispersion, deposition by precipitation and degradation in fresh water with novel methods that were developed during the application process. Moreover, the nitrosamine and nitramine concentrations were measured in air and fresh water lakes prior to start-up as a baseline. TCM's conclusion was that the risk was acceptable. The Norwegian Climate and Pollution Agency granted TCM a permit in November 2011.