Study of cardiovascular and auditory pathophysiological implications in a group of operatives working in noisy industrial surroundings.

One third of 160 operatives working in a permanently noisy industrial environment, within the range of 63-8000 Hz and intensity of sound of about 100 db, were found to suffer from a syndrome of neurocirculatory asthenia and 8.1% from arterial hypertension. Study of the ECG according to the criteria of the Minnesota code showed an increased frequency of upward deflection of ST segment (index 9-2) in 20.6% of the cases, depression of the ST segment with an ascending orientation in 50.62% of the cases and left ventricular hypertrophy (index 3-1 and 3-3) in 20% of the cases. Audiometry revealed loss of hearing at frequencies of 4000 CS in 16.1% of the cases. The results obtained suggest that the detrimental effects are not restricted only to hearing, but also that the alterations detected might evolve towards organic cardiac disorders.