The theme for this week’s sustainability research is POLLUTION
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Research in Details:
Research #1
Association between short-term exposure to air pollution and COVID-19 infection: Evidence from China
Highlights
There was a significant relationship between air pollution and COVID-19 infection after controlling for confounding factors.
Positive associations of PM2.5, PM10, CO, NO2 and O3 with COVID-19 confirmed cases were observed.
However, SO2 was negatively associated with the number of daily COVID-19 confirmed cases.
Authors: Zhu Yongjian, Xie Jingu, Huang Fengming, Cao Liqing
Date of publication: 15, April, 2020
Summary
The novel corona virus pneumonia, namely COVID-19, has become a global public health problem. Previous studies have found that air pollution is a risk factor for respiratory infection by carrying microorganisms and affecting body's immunity. This study aimed to explore the relationship between ambient air pollutants and the infection caused by the novel corona virus. Daily confirmed cases, air pollution concentration and meteorological variables in 120 cities were obtained from January 23, 2020 to February 29, 2020 in China. We applied a generalized additive model to investigate the associations of six air pollutants (PM2.5, PM10, SO2, CO, NO2 and O3) with COVID-19 confirmed cases. We observed significantly positive associations of PM2.5, PM10, NO2 and O3 in the last two weeks with newly COVID-19 confirmed cases. A 10-μg/m3 increase (lag0–14) in PM2.5, PM10, NO2, and O3 was associated with a 2.24% (95% CI: 1.02 to 3.46), 1.76% (95% CI: 0.89 to 2.63), 6.94% (95% CI: 2.38 to 11.51), and 4.76% (95% CI: 1.99 to 7.52) increase in the daily counts of confirmed cases, respectively. However, a 10-μg/m3 increase (lag0–14) in SO2 was associated with a 7.79% decrease (95% CI: −14.57 to −1.01) in COVID-19 confirmed cases. Our results indicate that there is a significant relationship between air pollution and COVID-19 infection, which could partially explain the effect of national lockdown and provide implications for the control and prevention of this novel disease.
Keywords: Air pollution, Novel corona virus pneumonia, COVID-19, Generalized additive model
Research #2
Limited long-distance transport of plastic pollution by the Orange-Vaal river system, South Africa
Highlights
Microfibres found at all sites and in 90% of replicates
Macroplastics and larger microplastics retained close to point sources
Mostly microfibres found at the Orange River mouth
Estimated annual export of 1.7 (1.1–3.1) t of microfibres to the Atlantic Ocean
Authors: Eleanor A. Weideman, Vonica Perold, Peter G. Ryan
Date of publication: 13 April, 2020
Summary
Much of the plastic waste entering the sea is thought to be transported from land by rivers, yet little is known about the distances over which rivers transport plastic. To address this knowledge gap, we collected surface water samples from the Orange-Vaal River at the end of the wet and dry seasons. The Vaal River drains South Africa's main urban-industrial centre, whereas the upper Orange River is sparsely populated. Below their confluence, the river flows through increasingly arid regions with very low human populations before entering the Atlantic Ocean. We collected bulk water samples from 33 bridges to test for microplastic and microfibre (0.025–1 mm) pollution and conducted observations for macrodebris (>50 mm). Where possible, we sampled for plastic fragments (>1 mm) using a neuston net. Microfibres and microplastics were found at every site (1.7 ± 5.1 L−1, >99% fibres) and accounted for 99% of the number of items recorded. Microfibres and microplastics were particularly abundant in the lower reaches during the period of low flow prior to the wet season flush. Macrodebris and larger microplastics were orders of magnitude less abundant (observations: 0.0002 ± 0.0007 items·m−2; neuston net: 0.34 ± 0.93 items·m−2). However, at sites where larger items were found, they comprised most of the mass of plastic. Larger plastics were found mostly at sites in the upper reaches of the Vaal River. Our results suggest that, while the Orange-Vaal River system may be a source of microfibres to the Atlantic Ocean, larger plastic items typically only travel short distances. The Orange-Vaal River system therefore does not appear to be a major source of plastics into the Atlantic Ocean, at least under regular flow conditions.
Keywords: Land-based sources, Mesoplastics, Plastic pollution, Source-to-sea, Surface water
Research #3
Acidic polymeric sorbents for the removal of metallic pollution in water: A review
Highlights
Functional polymers can be used as efficient sorbents for heavy metal removal
Chemical groups of polymers sorbents can be adapted to the targeted metallic removal
Modified polymers can be processed as requested by the treatment method
Natural polymers are good candidates for treatment of polluted wastewaters
Combining polymer architecture and functional groups can solve wastewaters depollution
Authors: Vincent Beaugeard, Julien Muller, Alain Graillot, Xianyu Ding, Jean-Jacques Robins, Sophie Monge
Date of publication: 13 April, 2020
Summary
The use of functional polymers for the sorption of metallic species in water was widely practiced in treatment processes. Such sorbents offered the possibility to remove a large range of metals because of the variety of possible functional groups on polymeric backbones. In particular, acidic groups (carboxylic, phosphonic or sulfonic groups) proved to be of great interest for the sorption of different cations. Sorption efficiency and selectivity through complexation or ion exchange interactions were directly linked to the nature of both the functional groups and the cationic metallic ions. In addition, the physical nature of materials was another important parameter that had to be considered. Depending on the polymer solubility, the cross-linking density, and the polymeric architecture, significant differences regarding sorption properties were observed in the sorption kinetics. Thus, it was challenging to select the appropriate polymeric sorbent with the most relevant physical nature and functionality in the area of wastewater treatment. This review aims at reporting organic polymeric materials bearing acidic groups able to interact (selectively or not) with metallic cations. Both synthetic and bio-based materials were reviewed and main parameters that had to be considered when choosing functional organic sorbents for the removal of metallic pollution were highlighted. Finally, recyclability of the polymeric sorbents was also considered.
Keywords: Functional macromolecules, Metallic pollutant, Water treatment, Aqueous wastewater
Research #4
The spatial relationship between traffic-related air pollution and noise in two Danish cities: Implications for health-related studies
Highlights
Development of a tool to model exposures to air pollution and noise
Investigation of spatial relationship of air pollution and noise at residential exposure level
First study to investigate the influence of traffic speed and AADT on air-noise relationship
First study to compare noise estimates of CNOSSOS and RTN-96 in Denmark
Overall lower to moderate correlations between levels of air pollution and noise
Authors: Jibran Khan, Konstantinos Kakosimos, Steen Solvang Jensen, Ole Hertel, Mette Sorenson, John Gulliver, Matthias Ketzel
Date of publication: 13 April, 2020
Summary
Air pollution and noise originating from urban road traffic have been linked to the adverse health effects e.g. cardiovascular disease (CVD), although their generation and propagation mechanisms vary. We aimed to (i) develop a tool to model exposures to air pollution and noise using harmonized inputs based on similar geographical structure (ii) explore the relationship (using Spearman's rank correlation) of both pollutions at residential exposure level (iii) investigate the influence of traffic speed and Annual Average Daily Traffic (AADT) on air-noise relationship. The annual average (2005) air pollution (NOx, NO2, PM10, PM2.5) and noise levels (Lday, Leve, Lnight, Lden, LAeq,24h) are modelled at address locations in Copenhagen and Roskilde (N = 11,000 and 1500). The new AirGIS system together with the Operational Street Pollution Model (OSPM®) is used to produce air pollution estimates. Whereas, noise is estimated using Common Noise Assessment Methods in the EU (CNOSSOS-EU, hereafter CNOSSOS) with relatively coarser inputs (100 m CORINE land cover, simplified vehicle composition). In addition, noise estimates (Lday, Leve, Lnight) from CNOSSOS are also compared with noise estimates from Road Traffic Noise 1996 (RTN-96, one of the Nordic noise prediction standards). The overall air-noise correlation structure varied significantly in the range |rS| = 0.01–0.42, which was mainly affected by the background concentrations of air pollution as well as non-traffic emission sources. Moreover, neither AADT nor traffic speed showed substantial influence on the air-noise relationship. The noise levels estimated by CNOSSOS were substantially lower, and showed much lower variation than levels obtained by RTN-96. CNOSSOS, therefore, needs to be further evaluated using more detailed inputs (e.g. 10 m land cover polygons) to assess its feasibility for epidemiological noise exposure studies in Denmark. Lower to moderate air-noise correlations point towards significant potential to determine the independent health effects of air pollution and noise.
Keywords: Traffic air pollution, Traffic noise, Relationship, CNOSSOS, OSPM®, Residential exposure
Research #5
Measures for reducing nitrate leaching in orchards: A review
Highlights
Improper management of nitrogen fertilizer leads to large amount of nitrate leaching.
Leached nitrates flow into river, penetrate the groundwater, causing water pollution.
Review orchard fertilization models and strategies on reducing the nitrate leaching.
Evaluate approaches of reducing nitrate leaching and improve efficiency in orchards.
Author: Meng Cui, Lihua Zeng, Wei Qin, Juan Feng
Date of publication: 10th April, 2020
Summary
Nitrogen (N) is one of the most important nutrients for plant growth. However, improper management of N fertilization in agriculture has led to a large amount of nitrate leaching, which is especially the case in fruit production systems. Studies have shown that high levels of nitrate in drinking water can cause harm to the human body. Excessive nitrate in rivers leads to eutrophication and damage to the ecological environment of the water. This study reviewed the measures and methods for reducing nitrate leaching in orchards. Some approaches for reducing nitrate leaching in orchards were evaluated, such as using grass cover, applying controlled-release N fertilizer, adding nitrification inhibitors, etc. These methods play important roles in reducing nitrate leaching in orchards, but more importantly, integrated measures are required to achieve agricultural sustainability and environmental protection goals.
Keywords: Nitrate leaching, Orchard, Drinking water pollution, Fertilization strategy, Model evaluation