Effects of Occupational Noise Exposure on Hearing Status, Blood Lipid and Hypertension Levels in Workers of a Fireclay Mine

Background: noise is one of the most pervasive hazards inindustrial settings. this retrospective study was carried out toassess the effects of noise exposure on hearing status, bloodlipids and blood pressure of employees of a local fireclay mine.methods: two hundred and forty male workers were studied. dataon audiometric measurements, blood lipids and blood pressurewere derived from the workers’ medical records and analyzed.furthermore, area noise measurements were performed. datawere analyzed using spss version 16.0.results: workers were exposed to a mean noise level of 91±15db. the means of triglyceride (tg), total cholesterol (tc),systolic and diastolic blood pressure (sbp and dbp) werewithin the normal range for the first three years of the study.however, a slight, non-significant increase in tg level was notedin 2010. most of the participants (63.6%) suffered from moderatehearing loss (hl). about 23.6% and 12.7% of the employeeshad developed severe and mild hl, respectively. a statisticallysignificant difference was noted in the number of workers withhigh-frequency noise-induced hl. furthermore, a statisticallysignificant association was found between the mean of highfrequencyhl and log-transformed tg values in 2009 and 2010.conclusions: high frequency hl could be used as a biomarkerfor identifying workers exposed to excessive noise levels. highfrequencyhl developed over a 4-year exposure to noise wasassociated with hypertriglyceridemia. implementing a hearingconservation program seems to be mandatory to prevent furtherincreases in the number of workers who are already in the severehl group.