The contribution of meteorological parameters and the COVID-19 partial lockdown on air quality in Rio de Janeiro, Brazil

This study evaluated the pollutant levels (NO2, SO2, CO, and O3), air quality index (AQI) and the influence of meteorological variables and coronavirus disease (COVID-19) pandemic on the air quality in Rio de Janeiro. The data set used comprises periods before (March-April, 2019) and during pandemic (March-April, 2020). According to the AQI results, on most days, the air quality was ranked as “good”. Brazilian air quality standards for SO2, O3, and NO2 were not exceeded in any of the monitoring stations during partial lockdown, while CO exceeded in all periods in one site due to industrial emission. Comparing both periods, descriptive statistics for the meteorological parameters presented no differences, which suggests similar conditions. However, when evaluated week by week in 2020, weather conditions presented some differences that probably affected pollutant concentrations. The correlations between O3 and NO2 and some meteorological parameters indicate that variations in both favored ozone formation, since it is a photochemical process favored by temperature and solar radiation and that, in Rio de Janeiro, low NO2 concentrations lead to increased O3. The improvements on air quality during the partial lockdown may be attributed mainly to a reduction on emission sources rather than weather conditions.Campus Lima Centr

Urban Particulate Matter Reaching Atlantic Rainforest Remnants Near Brazilian Metropolis: an Alert for Environmental Protection Authorities

The increasing air pollutant emission, mainly in big cities, attracts significant attention to environmental sciences. Brazil boasts an important tropical forest, the Atlantic Rainforest, and the most important remnants areas are located in the state of Rio de Janeiro. In that regard, this study aimed to assess the impact of particulate matter (PM) emitted by traffic in ecosystems belonging to environmental protection areas (EPAs) near important highways with heavy traffic in southeastern Rio de Janeiro, Brazil. To the best of our knowledge, this is the most comprehensive study on air pollution and its impacts on EPAs in Brazil. PM concentrations (TSP, PM10, and PM2.5) from 14 air quality monitoring stations and meteorological parameters were obtained between 2014 and 2016 near EPAs. It was verified that CONAMA annual standard (Brazilian legislation) was overtake in five monitoring stations and in eight of them CONAMA daily standard was exceed. Wind direction was mainly from urban centers to EPAs, indicating that urban pollutants reach forest remnants in most cases, which may represent ecological risk. In order to guarantee environmental preservation, new studies should be performed to evaluate deeply the effect of air pollutants on fauna and flora of preserved areas

Tracing the Origins of Air Contaminants Near Environmental Protection Areas

This case study aimed to assess the impact of particulate matter (PM) emitted by highway works in an ecosystem belonging to one of the most important Atlantic Rainforest remnants in southeastern Brazil. The study was conducted during federal highway works, comprising a toll station construction and lane widening. To the best of our knowledge, this is the most comprehensive study on air pollution and its impacts on Environmental Protection Areas (EPAs) in Brazil. Total suspended particle (TSP) samples were obtained from 2014 to 2016, totaling 1823 samples. Some TSP samples were chosen for ionic and elemental quantification. Daily concentrations ranged from 8 to 345 µg m−3. The TSP concentrations exceeded Brazilian guidelines (240 µg m−3), mainly during the federal highway works. The main determined elements Fe (50–2100 ng m−3) and Mn (3–30 ng m−3) were associated with soil origin. Trace elements (Cu, Co, Ni, V, and Pb), detected from 2 × 10−7 to 54 ng m−3, and high NO3− (2.4 − 8.3 µg m−3) and SO42− (2.6 − 6.8 µg m−3) concentrations were correlated with vehicular emissions. The findings of this study indicate that Cd and Cu represent environmental risks, as they may compromise biochemical plant processes.</p