Uniformed Services University School of Medicine Bethesda United States
Ethylbenzene, toluene, and xylene have been described as organic solvents that have potential ototoxic effects especially in combination with noise exposure. U.S. Navy personnel are often exposed to occupational hazards from various organic solvents and continuous noise while assigned to aircraft carriers. There is limited available data regarding organic solvent inhalation exposures to Navy personnel during shipboard operations. A total of 80 personal breathing zone samples were collected onboard a U.S. Navy aircraft carrier using a 3M Organic Vapor Diffusion Monitor to estimate the concentration levels of ethylbenzene, toluene, and xylene during job processes such as hazardous material HAZMAT issue, painting, fuel analysis, fuel pump maintenance, and oil testing. Over 90 of the sample results were below the laboratory limit of quantitation LOQ which required censored data analysis CDA for data evaluation. Additionally, 16 of 240 sample results were above the LOQ. All sample results were less than 10 of an adjusted 12-hr American Conference of Governmental Industrial Hygienists ACGIH Threshold Limit Value TLV. Data analysis showed that there was a statistically significant difference in toluene among HAZMAT exposure group as compared to the other homogenous exposure groups p 0.006. Organic solvent concentrations found during this study appear to be minimal compared to solvent concentrations that have been found to elicit adverse audiological outcomes in past studies. However, future research should aim to characterize exposure to other chemicals that may damage hearing over the course of the ships life cycle for a more comprehensive assessment to personnel assigned to aircraft carriers.