Disfunção auditiva induzida por agrotóxicos em trabalhadores agrícolas do Paraná

Abstract

The farmer is a worker who performs his duties in rural areas and despite the existence of public occupational health policies. In many cases, these professionals are unaware of the risks from their working environments to their health and their family’s health, as well as being unaware as to the means to prevent damage or effects related to farming. This study aimed to characterize the auditory dysfunction induced by pesticides with a focus on prevention. We conducted a cross-sectional study, divided into two stages. Step 1 included: questionnaire, otoscopy, pure-tone audiometry, acoustic impedance, high-frequency audiometry, in addition to a biological evaluation. The initial research group was formed by 70 agricultural workers with an average age of 39.7, an average exposure time of 23.7 years, while the control group consisted of 71 participants of both genders, with no exposure to noise and chemicals, average age of 39.5. Step 2 included: TEOAE, DPOAE and the suppression effect of TOAEs for the 24 participants from the research group with audiometric thresholds ≤ 40dB HL according to the tri-tone average (500, 1000 and 2000 Hz) or at a specific frequency (3, 4, 6 and 8 kHz). The results show significant differences between the groups (p <0.05%) for pure tone audiometry, high-frequency audiometry, acoustic reflex and TOAE, with worse results observed in the research group. The frequencies most affected in pure tone audiometry were high frequencies (from 3 to 6 kHz) and in high-frequency audiometry (from 9 to 11.2 kHz). Exposure to pesticides is associated with absence of acoustic reflex, reduced OAE signal/ noise ratio and dysfunction of the olivocochlear efferent auditory system. There is a positive correlation between the audiological findings (pure-tone audiometry, high-frequency audiometry, acoustic reflex and suppression effect) and the biological evaluation (aspartate aminotransferase, alanine transaminase, direct bilirubin, gamma-glutamyl transferase, proteins, creatinine, and urea exams). It is concluded that exposure to pesticides can cause hearing disorders, both central and peripheral, with involvement in the basal region of the cochlea and the olivocochlear efferent auditory system.