Ambient air pollution would increase morbidity in Great Casablanca

In Greater Casablanca, one of the sixteen former regions of Morocco that existed from 1997 to 2015 and the locomotive of the development of the Moroccan economy, ambient air pollution could increase emergency room visits among children and adults. A study conducted by ten researchers from different laboratories across the country and published by AIMS Press focuses on the relationship between ambient air pollutants and morbidity and emergency room visits among children and adults in said region.

Researchers evaluated in the short term the effect of air pollution on morbidity rates of the population of Greater Casablanca, which includes Casablanca and Mohammedia as well as the provinces of Nouaceur and Médiouna. 

During the period of study, the daily average concentrations of SO2, NO2, O3 and PM10 in Casablanca were 209.4 µg/m3, 61 µg/m3, 113.2 µg/m3 and 75.1 µg/m3, respectively. Based on the Moroccan National Ambient Air Quality Standards the standards limit values are 125 µg/m3 for SO2, 50 µg/m3 for NO2, 110 µg/m3 for O3 and 50 µg/m3 for PM10.

The researchers found that in children less than 5 years old, risk of asthma could be increased until 12% per 10 µg/m3 increase in NO2, PM10, SO2 and O3. In adults, an increase of 10 µg/m3 air pollutant can cause an increase up to 3% and 4% in respiratory consultations and acute respiratory infection.

Reduce risk factors and improve air quality

The results also suggest «an increase of 10 µg/m3 in the NO2, SO2, PM10 and O3 pollutant concentrations», while the number of emergency room visits due to respiratory diseases seems to be linked to the increase in air pollutants.

The study also recalls that in light of the pandemic of the novel coronavirus (Covid-19), several epidemiological and experimental studies show a relationship between air pollution and Covid-19, stating that «air pollution may play a role in morbidity and mortality associated with SARS-CoV-2».

For the 11 authors of this study, «small reduction in the level of risk factors may yield a great benefit for the health of the Great Casablanca population». «A reflection on the opportunities to develop feasible actions are needed in order to adopt the more stringent WHO targets. Decision-makers should prioritize the development and implementation of interventions in order to enhance the monitoring of ambient air quality at a local level and sensitize and educate citizens to raise awareness about the impact of air pollution on health», they plead.

The morbidity data (hospitalization and consultation) of residents of the studied area were extracted from different structures, including the Ibn Rochd university hospital in Casablanca, in addition to 9 hospitals, 35 primary care centers, 9 respiratory disease centers and 11 municipal health offices. At the end of each day, doctors filled out a form designed for this study, sent to the data collector. All morbidity data were collected from November 1, 2011 to October 31, 2013.