CH3COONO2

CH3COONO2, also known as peroxyacetyl nitrate (PAN), is a chemical compound with the molecular formula CH3COONO2. It is a member of the organic nitrate family and is characterized by the presence of a peroxyacyl group (-COONO2). PAN is a colorless liquid with a pungent odor.

PAN is a secondary air pollutant, meaning it is not directly emitted into the atmosphere but is formed through chemical reactions involving primary pollutants. Its formation is primarily associated with photochemical smog, particularly in urban and industrialized areas. Sunlight, nitrogen oxides (NOx), and volatile organic compounds (VOCs) are key ingredients for its production. In the presence of sunlight, NOx and VOCs react to form ozone and other reactive intermediates, which then react with peroxyacetyl radicals to produce PAN.

Due to its chemical properties, PAN is a relatively stable compound, allowing it to be transported over long distances from its source. This makes it a significant component of regional air pollution. PAN is known for its phytotoxicity, meaning it can cause damage to plants. It is a common cause of leaf damage, manifesting as bronzing or silvering of the undersides of leaves. This damage can impair plant growth and agricultural productivity.

In addition to its effects on vegetation, PAN can also irritate the eyes and respiratory system in humans, although its direct impact on human health is generally considered less severe than that of ozone. However, its presence contributes to the overall burden of air pollution and can exacerbate existing respiratory conditions. Understanding the formation, transport, and effects of PAN is important for air quality management and protecting both environmental and human health.