Ozone: Protective Layer and Its Broad Applications

The important function of ozone in environmental protection, its uses in industry and healthcare, and the approaches improving its preservation and technological developments are discussed in this article.

Introduction to Ozone

Ozone (O₃) is a triatomic molecule composed of three oxygen atoms, characterized by its distinct chemical properties, including its ability to absorb ultraviolet (UV) radiation and its role as a potent oxidizing agent. The molecule exists in two primary layers of the Earth’s atmosphere: the stratosphere and the troposphere. In the stratosphere, ozone forms a protective layer that absorbs the majority of the sun’s harmful UV radiation, thus playing a crucial role in protecting living organisms on Earth. Conversely, in the troposphere, ozone is a secondary pollutant formed through photochemical reactions involving volatile organic compounds (VOCs) and nitrogen oxides (NOx), contributing to smog and respiratory problems in humans (Kuang et al., 2017; Banerjee et al., 2016). Ozone’s occurrence is notably different in the stratosphere and troposphere. In the stratosphere, ozone is primarily formed through the photodissociation of molecular oxygen (O₂) by UV radiation, leading to a dynamic equilibrium between ozone production and destruction. This layer, often referred to as the ozone layer, is located approximately 10 to 50 kilometers above the Earth’s surface and is vital for filtering UV radiation (Butchart et al., 2010). In contrast, tropospheric ozone is not emitted directly but is formed by chemical reactions between precursors such as VOCs and NOx in the presence of sunlight, predominantly in urban areas. The variability of ozone levels in the troposphere is influenced by meteorological conditions, including stratosphere-to-troposphere transport (STT), which can introduce ozone-rich air from the stratosphere into the troposphere (Kuang et al., 2017; Trickl et al., 2010; Trickl et al., 2014). The importance of ozone in environmental chemistry cannot be overstated. In the stratosphere, it serves as a shield against UV radiation, significantly reducing the incidence of skin cancer and cataracts in humans, as well as protecting ecosystems (Butchart et al., 2010). In the troposphere, however, elevated ozone levels can lead to adverse health effects, including respiratory issues and decreased lung function, as well as damage to crops and other vegetation (Banerjee et al., 2016; Morgenstern et al., 2013). Furthermore, the interactions between stratospheric and tropospheric ozone are critical in understanding the overall oxidizing capacity of the atmosphere, which influences climate change and air quality (Morgenstern et al., 2013; Flury et al., 2009). The ongoing recovery of the ozone layer, primarily due to international agreements such as the Montreal Protocol, is expected to have positive implications for both stratospheric and tropospheric ozone levels in the future (Butchart et al., 2010; Revell et al., 2012). In summary, ozone is a vital component of the Earth’s atmosphere, with distinct roles in both the stratosphere and troposphere. Its protective function against UV radiation in the stratosphere contrasts sharply with its role as a harmful pollutant in the troposphere, highlighting the complex nature of this molecule in environmental chemistry.

Ozone’s Role in Environmental Protection

By absorbing most of the sun’s harmful UV (UV) radiation, the stratosphere’s ozone layer—which protects the environment—is absolutely vital. Maintaining life on Earth depends on this layer essentially blocking 97–99% of UV rays. As well as negative consequences on ecosystems, including lowered crop yields and damage to aquatic life, UV radiation is known to cause several health concerns including skin cancer, cataracts, and immune system suppression (Langematz, 2019; Kwon et al., 2022; Pareek, 2023). Preventing too high UV radiation that can cause genetic mutations and other long-term health effects, the ozone layer’s protective role is absolutely essential (Zhang, 2024; Norval et al., 2011).


Particularly brought on by human-made compounds like chlorofluorocarbons (CFCs), ozone depletion has major effects on ecosystems and human health. Rising UV radiation reaching the Earth’s surface has been connected to the loss of the ozone layer, therefore causing skin cancer incidence to rise as well as other UV-related health issues (Ahmad & Tasduq, 2022; Anwar et al., 2016). Furthermore impacted are ecosystems since higher UV radiation can disturb phytoplankton development in oceans, which forms the foundation of the marine food chain, and can also hinder photosynthesis in terrestrial plants, so influencing food security (Ahmad & Tasduq, 2022; Zhang, 2024). Beyond only immediate health hazards, ozone depletion can cause long-term ecological imbalances and biodiversity loss (Zhang, 2024; Norval et al., 2011).



Responding to the pressing need for ozone preservation, worldwide policies and accords have been developed; most famously, the Montreal Protocol was adopted in 1987. Considered generally as a successful environmental pact, this convention seeks to phase out the manufacture and use of ozone-depleting compounds (ODS). Studies have indicated that the Montreal Protocol has resulted in notable declines in the atmospheric concentrations of ODS, therefore helping to gradually restore the ozone layer (Mäder et al., 2010; Velders et al., 2007). Moreover, if present regulations are kept in place, continuous assessments show that the ozone layer is on route to return to pre-1980 levels by the middle of the 21st century (Parrondo et al., 2013; Madronich et al., 2021). The Montreal Protocol’s success shows the efficiency of worldwide cooperation in tackling environmental issues, which should guide next international environmental treaties (Mäder et al., 2010; Velders et al., 2007).



In essence, shielding life on Earth from damaging UV radiation depends on the ozone layer. The effects of ozone depletion on ecosystems and human health highlight the need of ongoing initiatives in ozone preservation. The Montreal Protocol and other international agreements have shown success in reducing ozone depletion, therefore emphasizing the vital need of world collaboration in environmental conservation.

Industrial and Medical Applications of Ozone

Especially in water treatment systems and air purification techniques, ozone (O₃) has become a potent agent in many different industrial and medical uses. Its special chemical qualities make it a useful oxidant and disinfectant, therefore promoting environmental sustainability as well as public health.

Ozone is used in water treatment systems because it can breakdown a broad spectrum of contaminants, including organic pollutants, bacteria, and viruses. Research on the kinetics of ozone inactivation of pathogens including prion proteins shows that, under continuous exposure, ozone can efficiently make wastewater safe for disposal. Ding & associates (2013). Unlike conventional chlorine treatments (Tripathi & Hussain, 2022), ozone treatment is beneficial since it breaks down complicated organic compounds into simpler, less dangerous chemicals, therefore improving water quality without leaving damaging residue. Moreover, the use of ozone in the dairy sector has showed potential in lowering pollution concentrations in wastewater, therefore underscoring its adaptability in many different industries (Varga & Szigeti, 2016).

Ozone is quite important in medical environments for sterilizing techniques and air cleaning. Strong oxidizing characteristics enable it to eradicate from surfaces and air microorganisms like bacteria, viruses, and fungi. Studies showing that concentrations as low as 250 ppm can achieve sterilization within a designated period of time have demonstrated that ozone can essentially disinfect medical equipment (Muto & Hayashi, 2023; Abuzairi et al., 2022). Furthermore integrated into plasma sterilization technologies, which employ ozone as an active species to efficiently destroy germs, is ozone (Santjojo et al., 2022). The fumigation of operation theaters using ozone emphasizes even more its relevance in preserving sterile surroundings in medical institutions (Patil & Vijayan, 2010).

Looking ahead, patterns in ozone technology point to increasing public health and sustainability being given more importance. Development of innovations in ozone generation and application techniques aims to improve efficiency and lower energy usage. To increase pollution degradation rates and extend the spectrum of contaminants that can be treated efficiently, for example, the combination of ozone treatment with advanced oxidation processes (AOPs) is under investigation (Suresh et al., 2020). Furthermore expected to increase its efficacy in reducing airborne infections and increasing indoor air quality is the combination of ozone technology with other air purification techniques, such photocatalyzed (Liu et al., 2023). The possibility of ozone supporting sustainable practices in many sectors, including environmental remediation and food manufacturing, emphasizes its adaptability and relevance in handling public health issues.

Ultimately, the uses of ozone in medical environments and water treatment highlight its importance as a strong oxidizing agent. A key component in attempts to raise public health and environmental quality, the continuous developments in ozone technology promise to increase their efficiency and sustainability.

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