What are the hazards of automobile exhaust?

Formation of photochemical smog: hydrocarbons and nitrogen oxides in automobile exhaust react with sunlight to generate ozone, which combines with other components in the atmosphere to form photochemical smog. Its harm to health is mainly manifested in irritating the eyes and causing pinkeye; Irritating to nose, throat, trachea and lungs, leading to chronic respiratory diseases. Photochemical smog will kill trees and greatly reduce crop yield; It will reduce atmospheric visibility and hinder traffic. Asphyxiation: Carbon monoxide in automobile exhaust has the highest content, which can enter alveoli through respiratory tract, be absorbed by blood, and combine with hemoglobin to form oxygenated hemoglobin, which reduces the oxygen carrying capacity of blood and weakens the oxygen supply of blood to human tissues, leading to tissue hypoxia, thus causing headaches and other symptoms, and even suffocation and death in severe cases. Stimulate lung tissue: the content of nitrogen oxides in automobile exhaust is small, but it is toxic, and its toxicity is three times that of sulfur oxides. After nitrogen-containing compounds enter alveoli, they can form nitrous acid and nitric acid, which will stimulate lung tissue violently, increase pulmonary capillary permeability and eventually cause emphysema. Nitrite combines with hemoglobin to form methemoglobin, which leads to tissue hypoxia.