Abstract: The city of Santos/SP is a densely populated area with the largest port in Latin America. This port is characterized by a high volume of vegetable dry bulk exports, and the handling of these products is known as a source of particulate matter emissions (PM10 and PM2.5). The air quality in Santos (with regard to PM10 and PM2.5) is influenced by the contribution of a natural portion, related to the sea mist, and an anthropogenic portion, including mainly vehicular traffic and commercial and industrial activities. Due to the availability of fuels and raw material, there are large industrial activities with the potential to influence air quality in the metropolitan region around Santos, which is called Baixada Santista. The emission of atmospheric pollutants in the Baixada Santista is especially critical due to the topographical conditions, notably the Serra do Mar mountain range, which forms an obstacle to the pollutants’s dispersion. In recent years there have been a number of improvements in industrial processes and in the facilities at the Port of Santos, which caused a reduction in the concentrations of PM10 and PM2.5, and consequently in the impact on the population’s health. The aim of this study is to quantify the benefits of these improvements in terms of reducing the impact on health. In order to do this, the deaths attributable to the pollutants PM10 and PM2.5 were calculated for the period from 2013 to 2019. The years 2020 to 2022 were not included due to the effect of COVID-19 on health data. The tool used for this analysis was the World Health Organization’s (WHO) AirQ+ software.The input data included average annual concentrations measured at two automatic air quality stations operated by CETESB, São Paulo’s state environmental agency: Estação Santos and Estação Santos – Ponta da Praia. Death data was obtained from DataSUS, a system from Brazilian Ministry of Health. The effects studied were: total deaths >30 years; deaths from diseases of the circulatory system >30 years; deaths from diseases of the respiratory system >30 years; and deaths from lung cancer >20 years. The results showed that the average annual concentrations of PM10 ranged from 48 μg/m3 in 2013 to 22 μg/m3 in 2019 in the Ponta da Praia Estuary, while the average concentrations of PM2.5 ranged from 19 μg/m3 to 14 μg/m3 in the same period. The concentrations considered as cut-off (No observed effect level) for each pollutant were: 10 μg/m3 for PM2.5 and 21.7 μg/m3 for PM10. In relation to health impact, the highest resulting attributable fraction was 17.80% for respiratory system diseases in 2014. In general, the attributable fractions decreased during the study period. In 2019, the impact with the highest calculated attributable fraction was lung cancer for the population >20 years, with 4.43%. In the reference period, there was a reduction in total deaths attributed to the effects of pollution, from 266 cases in 2013 to 124 in 2019 (a reduction of 53.4%). When comparing PM10 and PM2.5, the pollutant PM2.5 proved to have a greater impact on health. Deaths from circulatory problems were reduced from 123 in 2013 to 49 in 2019 (60.2% reduction). Deaths from respiratory problems were reduced from 92 in 2013 to 17 in 2019 (81.5% reduction). It is interesting to note that the pollutant PM10 was the main cause of deaths in this category until 2015, however, from 2016 onwards the impact calculated for the pollutant PM2.5 exceeded the impact calculated for PM10. Deaths from lung cancer were reduced from 17 in 2013 to 5 in 2019 (a 70.6% reduction). Despite the significant improvements observed in the period 2013-2019, still 124 cases attributable to PM2.5 were calculated for 2019, which reinforces the importance of continuing improvements in reducing emissions of this pollutant.

Keywords: Epidemiological study, fine particles, AirQ+ model, air pollution health impact, respiratory system disease.