User:Abdullah Murtaza korai/sandbox

Many biogenic processes also release carbon-containing molecules. For instance, when people, animals and other aerobic organisms breathe, they exhale carbon dioxide, or CO2, which is essential for algae, cyanobacteria and plants that survive using photosynthesis. This compound can also escape during the combustion of materials like wood, peat and coal during forest fires. Carbon monoxide, or CO, also comes from natural blazes, but its principal sources are related to industrial processes.

Like NO, CO and CO2 aren't VOCs. They can, however, react with existing VOCs to create ozone pollution. Other substances, such as methane, a hydrocarbon known for its negative greenhouse impacts, come from the fermentation of materials like manure. Icy methane deposits on the seafloor may also release increased amounts of this gas in the future.

All told, carbon-bearing VOCs from natural sources account for an estimated 1150 teragrams of emissions annually. By comparison, humans release 142 teragrams of carbon-bearing VOCs yearly. This distinction isn't to say, however, that human actions are any less of a problem for the atmosphere: Urban areas and other inhabited zones routinely have higher VOC concentrations than their natural surroundings, which can significantly increase the risks of VOC exposure.

Some estimates suggest that more than half of greenhouse gas emissions occur as a direct result of meat and dairy agriculture. In other words, even though animals like cows naturally release the substance when they belch, the massive scale of industrial livestock activities has a severely negative impact on the environment even with EPA regulations.

Humans also have a significant effect on otherwise-normal VOC-causing processes, such as vegetation growth, soil activity and biomass burning. Also, remember that natural sources aren't the only problem: Synthetic materials inside homes and offices emit VOCs too, so installing a smart indoor air quality monitor may be a wise health move.