Efeitos ototóxicos da exposição ao monóxido de carbono: uma revisão

Abstract

The review of the literature indicated the following: 1. Examples of CO exposure sources include air pollution, smoking and second-hand smoking, and occupational exposures. 2. CO's main toxic mechanism can lead to hypoxia due to the conversion of oxyhemoglobin to carboxyhemoglobin. 3. Rats have been the most used experimental animals in CO auditory effects studies, this group of studies has demonstrated the combined effects of acute exposure to CO and noise. 4. Studies about the negative effects of CO exposure over the human auditory system were mainly carried out after acute exposures to CO. These studies did not control or report exposure to noise as a contributor to the observed hearing deficits. Currently the available evidence indicates the need for further research on the effects of CO exposure to the auditory system, alone or in combination with noise.

Low and high frequency tonal threshold audiometry: comparing hearing thresholds between smokers and non-smokers

“…Carbon monoxide may also act directly on cochlear metabolism and cause alterations to the action potentials generated by auditory nerve fibers. Another effect reported about the carbon monoxide on the inner ear was the metabolic exhaustion of the succinate dehydrogenase enzyme, implicated in the Krebs cycle of the inner ear cells, especially of the outer hair cells, and the oxidation of nervous structures for the production of free radicals 11 . Nonetheless, most authors study threshold increases only in frequencies up to 8 kHz.…”

Qualidade de vida de tabagistas e sua correlação com a carga tabagística

“…CO has affinity for hemoglobin in the blood, which carries oxygen to all tissues in the body. Therefore, chronic CO intoxication resulting from prolonged exposure may cause cumulative toxic effects such as headache, fatigue, dizziness, nausea, respiratory diseases, cardiac ischemia, heart disease, and even decreased physical capacity [22][23][24] .…”

Pollutant Gas Emission by Automotive Vehicles in Recife - PE

“…Filho (1989) afirma que os principais gases contendo carbono são Monóxido de Carbono (CO) e Dióxido de Carbono (CO2). De acordo com Lacerda et al (2005) o escapamento dos veículos à combustão é responsável pela emissão de grandes concentrações de CO. Segundo Carvalho (2011) o setor de transporte é considerado uma das principais fontes de emissão de CO2. O excesso de CO é o resultante de uma combustão na qual a quantidade de ar é insuficiente para uma queima completa do combustível.…”