Page 4
When considering hearing loss in the lives of workers, it is very important to know other agents which can cause and/or worsen it - chemical products among them.
The first authors to discuss the interaction between noise and chemical products reported that the sensorineural hearing loss in workers exposed to solvents was more pronounced than expected in the case of noise exposure only4; this data was confirmed by another study.
One study assessed the audiological profile of workers exposed to noise and chemical products in an alcohol and sugar plant. The authors classified the audio-logical findings and discovered that: 40% of the people working in the areas where they were exposed to chemical agents had hearing loss degree 1, making up the highest percentage of losses. In the area where there was exposure to noise and chemical agents, 10% of the workers had hearing loss degree 1 and 20% had it in degree 2 - showing a lower number of hearing loss, but a worsening in the degree, pointing to the expanded harmful effects of the associated agents. In the noise exposure area, 20% of them had hearing loss degree . They noticed the existence of a hearing hazard not only in the noise-exposed area, but also in those exposed to chemical products, thus indicating a greater severity when the exposure is associated. In a comparative study of audiometric exams from metallurgical workers exposed to noise (group I) and noise associated with chemical products (group II), we noticed that group II individuals had a higher prevalence of hearing loss when compared to those individuals in Group I8. Within this line of research, studies are being carried out with “insect busters” -professionals who control vectors by means of chemical products, mechanical devices or any other way used to remove the agents which are harmful to the population and still, are exposed to noise. These workers use pyrethroids and organophosphates insecticides. These products were introduced in the group of high priority for studies associated with ototoxicity, in which we already had solvents, metals and asphyxiating substances.