Estimating ambient air pollution mortality and disease burden and its economic cost in Barcelona.

BACKGROUND: The new WHO air quality guidelines indicate that the air pollution disease burden is greater than previously reported. We aimed to estimate the air pollution disease burden and its economic cost in Barcelona to inform local action. METHODS: We used a quantitative health impact assessment to estimate the non-accidental mortality and incidence of childhood asthma and lung cancer attributable to long-term air pollution exposure in the city of Barcelona (Spain) in 2018-2019. We used the population weighted mean of PM2.5 and NO2 assigned at the geocoded address during the study period and the 2021 WHO air quality guidelines as counterfactual scenario to estimate new annual cases attributable to each pollutant separately and combined. We estimated the social cost of attributable deaths and the health care cost of childhood asthma and lung cancer attributable cases. We also estimated attributable mortality by city district and the mortality avoidable by achieving the WHO air quality interim targets. RESULTS: Mean exposure was 17 µg/m3 for PM2.5 and 39 µg/m3 for NO2. Total combined air pollution attributable mortality was 13% (95%CI = 9%-17%), corresponding to 1,886 deaths (95%CI = 1,296-2,571) and a social cost of €1,292 million (95%CI = 888-1,762) annually. Fifty-one percent (95%CI = 21%-71%) and 17% (95%CI = 7%-29%) of new cases of childhood asthma and lung cancer were attributable to air pollution with a health care cost of €4.3 and €2.7 million, respectively. Achieving the first unmet WHO air quality interim targets for PM2.5 and for NO2 would avoid 410 deaths and €281 million annually. CONCLUSION: Air pollution in Barcelona represents a huge disease and economic burden, which is greater than previous estimates. Much stronger measures to reduce PM2.5 and NO2 levels are urgently needed. Until the WHO air quality guidelines are met in the city, achieving each WHO air quality interim targets would avoid hundreds of deaths each year.

Effectiveness of the Modification of Sewers to Reduce the Reproduction of Culex pipiens and Aedes albopictus in Barcelona, Spain.

Mosquitoes breeding in urban sewage infrastructure are both a source of nuisance to the local population and a public health risk, given that biting mosquitoes can transmit pathogenic organisms to humans. The increasing presence of the invasive mosquito species Aedes albopictus in European cities has further exacerbated the problems already caused by native Culex pipiens. We tested the effectiveness of modifications to sewage structures as an alternative to the use of biocides to prevent mosquito breeding. The placing of a layer of concrete at the bottom of sand sewers to prevent water accumulation completely eliminated mosquito reproduction, and so eliminates the need for biocides in modified structures. Sewer modification is thus a valid low-cost alternative for mosquito control.