CO e CO₂ differences and impact on our lives.

CO and CO₂ are two of the main air pollutants, although they are two very similar molecules, they differ greatly in their environmental impact and on people's health. Carbon monoxide is, in a direct way, very harmful to human health while carbon dioxide, due to its low toxicity, is not directly harmful to health but is the main cause of the greenhouse effect, so indirectly it is very dangerous for human health, animals, plants and all living organisms on our planet.

Let's take a closer look at these two molecules.

Carbon monoxide (CO):

Carbon monoxide is a molecule composed of a carbon atom and an oxygen atom, it appears as a flammable, colorless, odorless and tasteless gas, for this reason it is very difficult to detect and can be lethal for animals, including humans.

Sources: the main sources of carbon monoxide are photochemical reactions occurring in the troposphere, volcanic eruptions, fires and all forms of combustion (industries, vehicles, cigarette smoke and heating domestic).

Air pollution: carbon monoxide is part of the cycle of chemical reactions that produce smog, it reacts with oxygen, in the presence of radiation, to form carbon dioxide and ozone: CO + 2O₂ + hv → CO₂ + O₃ thus carbon monoxide is dangerous for the environment in two ways, it forms carbon dioxide, which in turn gives rise to the greenhouse effect, and forms ozone (O₃) which is one of the main pollutants at the level of the earth's surface.

Toxicity (human health): The main symptoms of carbon monoxide poisoning are headache, mental confusion, physical weakness and chest pain. Depending on the exposure time and concentration, this molecule can lead to very serious pathologies and even death.

Carbon monoxide binds to hemoglobin, the main oxygen-carrying compound in the blood, and produces carboxyhemoglobin, which decreases the ability to carry oxygen in the blood and consequently inhibits the transport, delivery and utilization of oxygen throughout the body. The affinity of carbon monoxide with hemoglobin is 230 times higher than that of oxygen, so hemoglobin binds to carbon monoxide much more easily than oxygen. This chemical reaction can cause hypoxia, anoxia and consequently death.

Myoglobin also prefers to bind to carbon monoxide over oxygen, the bond between these molecules causes a reduction in cardiac activity and causes hypotension, which can lead to cerebral ischemia.

Carbon monoxide also causes peroxidation of brain lipids, which can lead to Grinker's myelinopathy, a disease of the central nervous system, which causes edema and necrosis in the brain, causing cognitive disturbances and impaired memory learning and movements.

Carbon dioxide CO₂

Carbon dioxide is a molecule composed of a carbon atom and two oxygen atoms; it is an acid gas, colorless and with a density of 50% higher than that of air. Since the industrial revolution its concentration in the atmosphere has almost doubled, causing global warming and acidification of the oceans.

Sources: the main natural sources of carbon dioxide are volcanoes, geysers and carbonate rocks, but it is also produced by all aerobic organisms, this includes bacteria, plants and animals, including humans .

But the main causes of the incredibly rapid increase in its concentration in the atmosphere is human activity, especially the combustion of oil, coal and gas, but also deforestation and the cement industry.

Atmospheric Pollution: as previously mentioned since the industrial revolution, the concentration of carbon dioxide in the atmosphere has increased by 50%, and human activities are the main cause, just think that these processes introduce into the Atmosphere more than 30 Billion tons of CO ₂ per year, for comparison, volcanoes emit 0.3 Billion tons of CO ₂ per year. Human activity has caused an increase in CO ₂ that has not been seen for hundreds of thousands of years, its concentration is so high that the oceans and forests are no longer able to absorb it and consequently the carbon dioxide remains in the atmosphere, causing the greenhouse effect and therefore global warming.

Ocean pollution: carbon dioxide is soluble in water, this means that it dissolves in the oceans producing carbonic acid, bicarbonate and carbonate. The ocean is like an immense filter for carbon dioxide, over the years it has absorbed almost a third of the carbon dioxide emitted by human activities, therefore as the concentration of CO ₂ increases. in the atmosphere also increases its concentration in the oceans, this causes the acidification of the waters, which has a huge impact on living organisms in the ocean, starting from the smallest, such as plankton, corals and algae, up to higher rungs of the oceanic food chain, compromising even the survival of the fish we eat.

Toxicity (human health): at high concentrations, carbon dioxide can cause problems in the human body, the main symptoms are mental confusion, headache, visual and hearing dysfunction and loss of consciousness. Although it is very rare to be exposed to such concentration levels, it can happen in enclosed spaces with poor ventilation.

To avoid a further increase in the concentration of these molecules in the atmosphere we must start limiting their emissions, and where possible choose other sources of energy to use, only in this way can we preserve the oceans and forests, and the life contained in them. as they are our main allies in the fight against global warming.