Long-term commuting times and air quality relationship to COVID-19 in São Paulo

The Coronavirus Disease 2019 (COVID-19) epidemic is an unprecedented global health crisis and the effects may be related to environmental and socio-economic factors. In São Paulo, Brazil, the first death occurred in March 2020 and since then the numbers have grown to 175 new deaths per day in April 2021, positioning the city as the epicenter of the number of cases and deaths in Brazil. São Paulo is one of the largest cities in the world with more than 12 million inhabitants, a fleet of about 8 million vehicles and frequent pollutant concentrations above recommended values. Social inequalities are evident in the municipality, similarly to other cities in the world. This paper focuses on transportation activities related to air pollution and associated with cardiovascular and respiratory diseases especially on people who developed comorbidities during their whole life. This study relates travel trip data to air quality analysis and expanded to COVID-19 disease. This work studied the relationship of deaths in São Paulo due to COVID-19 with demographic density, with family income, with the use of public transport and with atmospheric pollution for the period between March 17th, 2020 and April 29th, 2021. The main results showed that generally passenger kilometers traveled, commuting times and air quality related diseases increase with residential distance from the city center, and thus, with decreasing residential density. PM_2.5 concentrations are positively correlated with COVID-19 deaths, regions with high urban densities have higher numbers of deaths and long-distance frequent trips can contribute to spread of the disease.

Characterization of particles emitted by pizzerias burning wood and briquettes: a case study at Sao Paulo, Brazil

The burning of biomass in pizza ovens can be an important source of air pollution. Fine particulate matter represents one of the most aggressive pollutants to human health, besides the potential to interfere with global radiative balance. A study in real-world condition was performed in three pizzerias in São Paulo city. Two of the pizzerias used eucalyptus timber logs and one used wooden briquettes. The results from the three pizzerias revealed high average concentrations of PM_2.5: 6171.2 μg/m³ at the exit of the chimney and 68.2 μg/m³ in indoor areas. The burning of briquette revealed lower concentrations of PM_2.5. BC represented approximately 20% and 30% of the PM_2.5 mass concentration in indoor and at chimney exhaust, respectively. Among the trace elements, potassium, chlorine and sulphur were the most prevalent in terms of concentration. Scanning electron microscopy (SEM) analysis revealed particles with an individual and spherical morphology, i.e. the conglomeration of spherical particles, flattened particles in the formation of fibres, the overlapping of layers and the clustering of particles with sponge-like qualities. The average emission factors for PM_2.5 and BC due to the burning of logs were 0.38 g/kg and 0.23 g/kg, respectively. The total emissions of PM_2.5 and BC were 116.73 t/year and 70.65 t/year, respectively, in the burning of timber logs.

Air Quality during COVID-19 in Four Megacities: Lessons and Challenges for Public Health

The study described in this manuscript analyzed the effects of quarantine and social distancing policies implemented due to the Coronavirus Disease 2019 (COVID-19) pandemic on air pollution levels in four western megacities: São Paulo in Brazil; Paris in France; and Los Angeles and New York in the United States. The study investigated the levels of four air pollutants-Carbon monoxide (CO), Ozone (O3), Fine Particulate (PM2.5) and Nitrogen dioxide (NO2)-during the month of March 2020, compared to 2015-2019, in the urban air of these metropolitan areas, controlling for meteorological variables. Results indicated reductions in the levels of PM2.5, CO and NO2, with reductions of the latter two showing statistical significance. In contrast, tropospheric ozone levels increased, except in Los Angeles. The beneficial health effects of cleaner air might also help prevent deaths caused by the epidemic of COVID-19 in megacities by diminishing pressure on hospitals and health equipment. Future actions for the re-starting of non-essential economic activities in these cities should take into consideration the overall importance of health for the individual, as well as for societies.

Heavy truck restrictions and air quality implications in São Paulo, Brazil

This study quantified the effects of traffic restrictions on diesel fuel heavy vehicles (HVs) on the air quality of the Bandeirantes corridor using hourly data obtained by continuous monitoring of traffic and air quality at sites located on this avenue. The study addressed the air quality of a city impacted by vehicular emissions and that PM₁₀ and NO_X concentrations are mainly due to diesel burning. Data collection was split into two time periods, a period of no traffic constraint on HVs (Nov 2008 and 2009) and a period of constraint (Nov 2010, 2011 and 2012). We found that pollutants on this corridor, mainly PM₁₀ and NO_X, decreased significantly during the period from 2008 to 2012 (28 and 43%, 15.8 and 86.9 ppb) as a direct consequence of HV traffic restrictions (a 72% reduction). Rebound effects in the form of increased traffic of light vehicles (LVs) during this time had impacts on the concentration levels, explaining the differences between rates of reduction in HV traffic and pollutants. Reductions in the number of trucks resulted in longer travel times and increased traffic congestion as a consequence of the modal shift towards LVs. We found that a 51% decrease in PM₁₀ (28.8 μg m^-3) was due to a reduction in HV traffic (vehicle emissions were estimated to be 71% of total sources, 40.1 μg m^-3). This percentage was partially offset by 10% more PM₁₀ emissions related to an increase in LV traffic, while other causes, such as climatic conditions, contributed to a 13% increase in PM₁₀ concentrations. The relationships analyzed in this research served to highlight the need to apply urban transport policies aimed at decreasing pollutant concentrations in São Paulo, especially in heavily congested urban corridors on working days.