Ozone Story

September 16 was proclaimed as the International Day for the Preservation of the Ozone Layer by the United Nations General Assembly. It was on this day in 1987 that the Montreal Protocol to control production and consumption of Ozone Depleting Substances was signed by various countries at Montreal, Canada. Since then this day is used as an opportunity to bring to public attention the importance of the Ozone layer and the threats to it caused by human activities.

The theme for this year’s World Ozone Day is ‘32 Years and Healing’. This celebrates one of the few success stories in the gloom and doom of news about the environment. The healing is the outcome of three decades of international cooperation to protect the ozone layer and the climate.

On reading about this I felt a sense of satisfaction at having contributed in a teeny-tiny way to the healing effort. It was in 1997 that the Centre for Environment Education got engaged in a variety of projects to raise awareness about the issue to a wide range of audiences—from school children to policy makers. As part of this we developed educational material that could communicate the somewhat complex science in a simple way, as well as motivate people to take action to prevent what was then an ominously growing hole in the ozone layer.

Today both the science and the understanding has advanced greatly, but it is still useful to remember some ozone basics.

OOOzone: When it is alone, it is called an oxygen atom. When two oxygen atIMG_20190917_152811.jpgoms get together, it is called oxygen molecule or just oxygen. When three oxygen atoms get together, it is called an ozone molecule!

Where is Ozone? A thin invisible layer of ozone gas is found in the upper atmosphere 15-60 km above the earth. This is called the ozone layer.

How much Ozone? There are only one to ten units of ozone in every million units of gas or particles in the upper atmosphere. Instruments measure ozone in parts per million (ppm).

What does the ozone layer do for us? In the upper atmosphere, the ozone layer acts as a natural shield. It protects the earth and its inhabitants by absorbing the harmful part of the ultraviolet radiation from the sun. Too much ultraviolet radiation is dangerous for all living creatures—humans, animals and plants.

What kind of danger? In humans it may increase the rate of skin cancers, eye problems and cataracts; and also weaken the immune system. It can reduce crop yields as plants will have reduced leaf size and germination time. It could kill phytoplankton—the base of the food chain in water and disturb the entire aquatic food chain. It can also damage paints and fabrics, as well as plastic.

How is the ozone layer damaged? By the use of Ozone Depleting Substances (ODS) which include chemicals called CFCs and Halons, which are released through human activities, and which float into the upper atmosphere.

In the last thirty years since the awareness about the danger from these substances was recognised, there has been a consistent effort at national and global levels to phase out the ODS, through policies, international agreements, and R&D in industry to find better substitutes. The Montreal Protocol has led to the phase-out of 99 per cent of ozone-depleting chemicals in refrigerators, air-conditioners and many other products.

However there are still products in the market that could potentially be threats. As consumers we can all play a role in protecting the layer that protects us, through the choices we make. Here are some tips on what we can avoid. Avoid aerosols whether for pesticides or perfumes. Avoid Styrofoam glasses and plates; use reusable steel and glass vessels. Avoid foam mattresses and pillows, use traditional cotton or coir products.  We must also remain vigilant to tackle any illegal sources of ozone-depleting substances as they arise

While we can celebrate success this year, this day is also a reminder that we must keep up the momentum to ensure healthy people and a healthy planet.

–Mamata