Modelling Arsenic, Lead, Cadmium and Nickel Ambient Air Concentrations in Spain

Ambient air levels of metals are included in the EC air quality standards due to their impact on human health and ecosystems. European directives 2008/50/CE and 2004/107/CE regulate lead, arsenic, cadmium, mercury and nickel ambient air levels. Air quality models constitute a powerful tool to understand tropospheric dynamics and to assign concentration values to areas where no measurement is available. For this reason models are currently being extensively applied in a variety of air quality applications. Metals have been more recently included in air quality models, and until now just studies showing results for some of them (mainly lead, cadmium and mercury) may be found in the literature. An attempt to simulate ambient air levels of arsenic, cadmium, lead and nickel in Spain has been done, by using the CHIMERE chemistry-transport model. An evaluation of model predictions was performed by comparing daily simulated values with observations in a set of monitoring sites for 2007. In overall, the model reproduces the temporal observed behavior, and it is able to simulate the high values measured in specific areas, such as those for lead and cadmium in Northern Spain. More refinement in emission database joined to higher-resolution simulations are required to better simulate this type of pollutants.