By Ranil Senanayake –

Dr. Ranil Senanayake

The ability of expressing our fundamental right to breathe clean air is over. The Global Commons of air is rapidly being impacted, in addition to an increase in the concentration of Carbon Dioxide and a decrease in Oxygen concentration. The concentration of toxic gasses and airborne particulate matter in the atmosphere is increasing. While a global compact on the quality of air as a fundamental right, is urgent consideration of its impact on health must also become a matter of concern. The most essential thing for our existence is the ability to breathe. The air that we take for granted is like an invisible river of gasses considered a part of the ‘Global Commons’ or those resources that extend beyond political boundaries. The Commons of air is composed of a mix of gasses, the dominant being Nitrogen at about 78%, followed by Oxygen at 21%. Carbon Dioxide that is contributing to climate change accounts for only 0.04% and demonstrates how small changes in the concentration of gasses in the atmosphere can bring about massive changes to those that live in it.

The Oxygen component of the air we breathe was made by those earliest plants, the Bryophytes, which colonized land from 470 Ma onwards. This land colonization increased atmospheric oxygen to present levels by 400 Ma. The fire-mediated feedbacks that followed have stabilised high oxygen levels ever since, shaping subsequent evolution of life. Oxygen is the most crucial element on earth for the aerobic organisms that depend on it to release energy from carbon-based macromolecules. The current stocks have been maintained over millions of years by plants, terrestrial and oceanic. To sustain a gaseous concentration at around 21% of the air we breathe. This level is required to maintain a healthy body and mind. A lowering of this concentration has consequences. At 19% physiologically adverse effects begin. Impaired thinking and attention, reduced coordination, decreased ability for strenuous work is experienced, at 15% Poor judgment, faulty coordination, abnormal fatigue upon exertion, emotional upset Levels below this lead not only to very poor judgement and coordination but also impaired respiration, lung and heart damage. The question often arises: If the atmospheric Oxygen concentration is 21% how can it vary so widely in different areas? The answer is that when you add other gasses, smoke and aerosols into the atmosphere, the concentration of atmospheric gasses will decrease in concentration. In some cities like New Delhi or Mexico have Oxygen concentrations measured at about 18% or lower.

There has been a clear decline in the volume of oxygen in Earth’s atmosphere over the past 20 years. Although the magnitude of this decrease appears small compared to the amount of oxygen in the atmosphere, it is difficult to predict how this process may evolve, due to the brevity of the collected records. A recently proposed model predicts a non-linear decay, which would result in an increasingly rapid fall-off in atmospheric oxygen concentration, with potentially devastating consequences for human health.

The free Oxygen in the atmosphere is 1.2×10¹⁵ tonnes (12,000,000,000,000,000 t), but it is unstable in our planet’s atmosphere and must be constantly replenished by photosynthesis in green plants. Without plants, our atmosphere would contain almost no O₂. An important thing that needs international address is the fact that the system that replenishes the Oxygen of our atmosphere is under threat. We remove the vegetation that produces the Oxygen at a prodigious rate. According to Global Forest Watch we fell about 15 billion trees each year. With one tree one tree producing about 120Kg of Oxygen per year, the loss of Oxygen production  through deforestation is massive. The impact on the oceans is becoming just as serious.

As human activities have caused irreversible decline of atmospheric O₂ and there is no sign of abatement, It is time to take actions to promote O₂ production and pay for industrial use and consumption of O₂ . Vehicular traffic in cities with poor air flow design transforms molecular oxygen O₂  into Ozone O₃. Ozone is good when it is high up in our atmosphere. It protects us from sunburn. Ozone is bad when it is near the ground where we can breathe it in. You can’t see ozone in the air but  bad ozone levels is sometimes called smog. It is formed when chemicals coming out of cars and factories are cooked by the hot sun. Breathing in ground-level ozone can make you cough. It can also make it harder for you to breathe. Ozone might even make it hurt to take a breath of air. When you breathe in ozone, it  makes the lining of your airways red and swollen, like your skin would get with a sunburn.

All this becomes even more pressing with the discovery of the “human oxidation field” a beneficial chemical microenvironment formed around the body’s surface that helps protect it from volatile organic compounds (VOCs). This field is generated by the reaction of ozone with oils and fats on our skin, especially the unsaturated triterpene squalene, which constitutes about 10 percent of the skin lipids that protect our skin and keep it supple. The reaction releases a host of gas phase chemicals containing double bonds that react further in the air with ozone to generate substantial levels of OH radicals. As the Ozone levels as in cities rise, the individual ‘human oxidation field’ looses its ability to maintain skin health.

In looking at the question of why there was such a rapid loss in the quality of air, the first study to systematically analyse the global O₂ budget and its changes over the past 100 years, found that anthropogenic fossil fuel combustion is the largest contributor to the current O₂ deficit, which consumed 2.0 Gt/a in 1900 and has increased to 38.2 Gt/a by 2015.

The inability to defend our fundamental right to breath seems to stem from the ability of any industry to discount the consequences of burning fossil fuels as a ‘negative externality’. Climate Change is one consequence, but the impact that lowered Oxygen concentrations will have on emerging urban populations seem disturbing. There is only one way to arrest the fall in atmospheric Oxygen, increase the rate of photosynthesis. There must be a protection of the existing stocks of photosynthetic biomass and programs that encourage  increasing the standing stock of Oxygen to be able to sustain our fundamental right to breathe clean air.