Ozone Pollution: A Major Health Hazard Worldwide

Abstract

Oxides of nitrogen (NOx) and volatile organic compounds (VOCs) released into the atmosphere can react in the presence of solar irradiation, leading to ozone formation in the troposphere. Historically, before clean air regulations were implemented to control NOx and VOCs, ozone concentrations were high enough to exert acute effects such as eye and nose irritation, respiratory disease emergencies, and lung function impairment. At or above current regulatory standards, day-to-day variations in ozone concentrations have been positively associated with asthma incidence and daily non-accidental mortality rate. Emerging evidence has shown that both short-term and long-term exposures to ozone, at concentrations below the current regulatory standards, were associated with increased mortality due to respiratory and cardiovascular diseases. The pathophysiology to support the epidemiologic associations between mortality and morbidity and ozone centers at the chemical and toxicological property of ozone as a strong oxidant, being able to induce oxidative damages to cells and the lining fluids of the airways, and immune-inflammatory responses within and beyond the lung. These new findings add substantially to the existing challenges in controlling ozone pollution. For example, in the United States in 2016, 90% of non-compliance to the national ambient air quality standards was due to ozone whereas only 10% was due to particulate matter and other regulated pollutants. Climate change, through creating atmospheric conditions favoring ozone formation, has been and will continue to increase ozone concentrations in many parts of world. Worldwide, ozone is responsible for several hundreds of thousands of premature deaths and tens of millions of asthma-related emergency room visits annually. To combat ozone pollution globally, more aggressive reductions in fossil fuel consumption are needed to cut NOx and VOCs as well as greenhouse gas emissions. Meanwhile, preventive and therapeutic strategies are needed to alleviate the detrimental effects of ozone especially in more susceptible individuals. Interventional trials in humans are needed to evaluate the efficacy of antioxidants and ozone-scavenging compounds that have shown promising results in animal studies.

Assessing the immediate impact of COVID-19 lockdown on the air quality of Kolkata and Howrah, West Bengal, India

“…The role of atmospheric chemistry is important here. The minimum concentration of other pollutants may result in the increase O 3 concentration because hiking of O 3 is caused by lower titration of O 3 by NO due to the minimum emission of NOx from the vehicle (Sicard et al 2020 ) and with a decreasing carbonaceous concentration increase the atmospheric visibility that promotes penetration of solar radiation favouring ozone formation (Zhang et al 2019 ) that can be understood from the concentration pattern of O 3 . The highest concentration of O 3 has been recorded at Rabindra Bharati (53.66 µg/m 3 ), and very minimum concentration of NO 2 (15.61 µg/m 3 ) and NH 3 (22.52 µg/m 3 ) has been noted on 3 May.…”

“…CO also reacts with O 3 (Jaffe 2012 ) . The breakdown of ozone produces oxygen and the oxygen reacts with CO in the atmosphere through the reaction is not direct (Zhang et al 2019 ).…”

Links between air pollution and COVID-19 in England

“…Ozone is a secondary by-product of traffic-related air pollution and is generated through sunlight-driven reactions between motor-vehicle emissions and volatile organic compounds 27 . Generally, high ozone levels have been associated with reduced lung function and increased incidence of respiratory symptoms 28 .…”

COVID-19 Lockdown: Lessons learnt using multiple air quality monitoring station data from Kolkata City in India

“…O 3 can cause adverse respiratory effects such as shortness of breath, chronic respiratory symptoms (i.e. coughing and sore or scratchy throat, phlegm, wheezing and in ammation of the airways) in the general population (Zhang, Wei, & Fang, 2019). These respiratory symptoms can further aggravate lung diseases such as asthma, emphysema, chronic obstructive pulmonary disease (COPD) and cardiovascular disease (Karthik , Sujith, Rizwan , & Sehgal, 2017).…”