Knowing more on Ozone Depleting Substances (ODS)

Chemicals that deplete the earth’s protective ozone layer are known as ozone depleting compounds. Chlorofluorocarbons (CFCs), for example, Chlorofluorocarbons (CFCs), carbon tetrachloride, and methyl chloroform are key ozone-depleting gases created by humans and employed in a variety of applications such as refrigeration, air conditioning, foam blowing, cleaning of electronic components, and as a solvent.

Ozone depleting compounds are man-made gases that deplete the ozone layer once they reach it. The ozone layer is located in the high atmosphere and helps to minimise the amount of dangerous ultraviolet light that reaches Earth from the sun. Ultraviolet radiation can be harmful to both individuals and the environment.

Ozone Depleting Substances (ODS)

Ozone is produced naturally in the stratosphere. Ozone-depleting substances (ODS) such as chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) are man-made compounds, and halons, methyl bromide, carbon tetrachloride, and methyl chloroform are gradually degrading this “healthy” ozone layer.

Ozone Depleting Substances (ODS) are given below:

• Hydrobromofluorocarbons
• Methyl bromide
• Carbon tetrachloride
• Halons
• Chlorofluorocarbons (CFCs)
• Methyl Chloroform

Hydrobromofluorocarbons

Hydrobromofluorocarbons (HBFCs) are molecules that include one, two, or three carbon atoms as well as at least one hydrogen, bromine, and fluorine atom. Because hydrobromofluorocarbons have ozone-depleting potential (ODP), they are classified as ozone-depleting chemicals (ODS).

Methyl bromide

Methyl bromide is a naturally occurring chemical that is used as a fumigant to control pests in soil, food and nonfood commodities, and structures. Its pesticidal use has diminished as a result of the Montreal Protocol’s phase-out of ozone-depleting chemicals. The main cause of toxicity in humans and animals is inhalation of methyl bromide gas.

Methyl bromide is a neurotoxin. It also causes respiratory, cardiovascular, reproductive, and developmental toxicity in animals. Despite being genotoxic, methyl bromide has not been designated as a human carcinogen. In the case of human poisoning, supportive therapy is used.

Carbon tetrachloride

CCl4 is the culprit behind the sickly sweet odour associated with dry cleaning solvents from decades past. It is a known air toxin that depletes the ozone layer; the gas accounts for around 10-15% of the ozone-depleting compounds in the atmosphere today.

Carbon tetrachloride (CCl4) was previously widely used as a cleaning agent and is still utilised in the chemical industry. CCl4 is the culprit behind the sickly sweet odour associated with dry cleaning solvents from decades past. It is a known air toxin that depletes the ozone layer; the gas accounts for around 10-15% of the ozone-depleting compounds in the atmosphere today. As a result, manufacture for applications that result in CCl4 leaking into the atmosphere has been prohibited for many years around the world.

Halons

Halons, which were widely employed in fire extinguishers and explosion suppression systems, have an extraordinarily high potential for ozone depletion ten times more potent than CFCs and also operate as a global warming agent (three and a half thousand times more potent than carbon dioxide (CO2).

Chlorofluorocarbons (CFCs)

When gaseous CFCs slowly rise into the stratosphere, they are broken down by strong ultraviolet radiation, releasing chlorine atoms, which subsequently combine with ozone molecules. Man-made chemical ozone depletion is mostly caused by chlorofluorocarbons (CFCs) and other halogenated ozone-depleting substances (ODS). The equivalent effective stratospheric chlorine is the entire amount of effective halogens (chlorine and bromine) in the stratosphere (EESC).

Methyl Chloroform

Chloroform contributes to the stratospheric ozone layer depletion. However, because of its short lifetime and reliance on natural sources, it is not covered by the Montreal Protocol, which governs the manufacture and use of ozone-depleting compounds.

As an industrial solvent, methyl chloroform is employed. Carbon tetrachloride has an ozone depletion potential of 0.11.

Environmental impact of ozone-depleting compounds

Increased UV radiation levels at the Earth’s surface are caused by ozone layer depletion, which is harmful to human health. Among the unfavourable consequences are increases in some types of skin cancer, ocular cataracts, and immunological deficiency issues. UV radiation also has an impact on land and aquatic ecosystems, changing growth, food chains, and metabolic cycles. High UV levels have a particularly harmful influence on aquatic animals that live close to the water’s surface, which serves as the basis of the food chain. UV rays also have an impact on plant growth, lowering agricultural productivity.

Conclusion

In this article we learned that, Chemicals that deplete the earth’s protective ozone layer are known as ozone depleting compounds. CFCs, HCFCs, halons, methyl bromide, carbon tetrachloride, hydrobromofluorocarbons, chlorobromomethane, and methyl chloroform are all examples of ODS. ODS are normally relatively stable in the troposphere and only degrade in the stratosphere under severe ultraviolet light.

These gases, which are emitted at the surface, are transported globally through the lower atmosphere via wind transport patterns.