Farming is an essential part of human civilization, providing the food and resources necessary for survival. Agricultural air pollution comes from both farm equipment and farming itself, which includes the soil, plants, animals and fertilizers. A study published in Geophysical Research Letters found that emissions from farms outweigh all other human sources of fine-particulate air pollution in much of the United States, Europe, Russia and China. The harmful gases from agricultural practices can have a significant impact on air quality, which inevitably affects mankind. Research shows that animal agriculture alone is responsible for 80% of deaths from pollution related to food production.