Exposure to pollutants Risk model in the Aburrá Valley (Expor2)

The study presents a framework for a human exposure model to pollution based on Chemical Transport Models (CTMs) for the urban area of Medellín in Colombia, including the metropolitan area in which is situated in the the city. The exposure model utilises pollutant concentration simulations obtained from the LOTOS-EUROS CTM drived by the WRF Numerical Weather Model (NWM) simulations conducted in January 2019 within the Aburrá Valley. The simulations provide spatial and temporal resolutions of 1 km x 1 km and 1 hour, correspondingly. This study applies the data from the 2017 Origin Destination Survey, which surveyed 16,340 households and 36,364 individuals living in urban and rural areas of the 10 municipalities of the Aburrá Valley. This data on demographic variables and weekday travel patterns helped to analyse human behaviour and intra-urban migration in order to develop a precise measure of daily pollution exposure for different geographic zones. The total mean exposure is calculated from the linear combination of  the exposure time and the mean concentration in every zone.

The study examined the morphological composition of fine particulate matter PM2.5 and PM10, resulting in the identification of six distinct groups, including mineral, organic/biogenic, tire wear, metallic, paint with high titanium content, and salts. Cytogenotoxicity tests assess the survival rates of cells in eye, skin and lung tissues. The resulting data is extrapolated to determine an irrigation factor specific to the urban area. It is worth highlighting that the central and southern regions of the Aburrá Valley, designated by high population density and multiple sources of pollution, exhibit heightened pollution exposure. On the other hand, the assessment of high-risk regions in the central zone is influenced by the lack of information in other parts of the urban area.