Background and objectives: The aim of this study was to investigate the occurrence of hypertransaminasemia (hTAMSemia) as an indicator of liver damage and to establish the association of this hepatotoxicity with exposure to aromatic hydrocarbons (benzene, toluene, and xylene [BTX]) among workers in a petrochemical company.
Patients and method: The medical records of 167 industrial employees, 95 with hydrocarbon exposure (EHCs) and 72 without exposure (NEHCs) were reviewed. Age, sex, number of years employed, body mass index, and biochemical and hematological parameters were evaluated. Employees with previous liver disease, diabetes mellitus, or alcohol intake (> 50 g/day) were excluded. In employees with hTAMSemia, we performed a proteinogram and hepatic ultrasonography and tested blood samples for prothrombin and hepatitis B and C markers. Within this subgroup, 3 workers were excluded (due to serum markers of hepatitis B virus in 2 and refusal to participate in 1), leaving a total of 92 in the EHC group. Finally, the working environment was screened for volatile contaminants.
Results: Twenty-seven employees from the EHC group (29.4%) and 1 from the NEHC group (1.4%) had hTAMSemia (p = 0.001). The remaining biochemical tests and parameters measured showed no significant differences between the two groups. Comparison between the EHC subgroup of 27 workers showing hTAMSemia and the remainder of the EHC group with normal values (65 workers) revealed no differences in the other parameters measured. Of the 27 workers of the former subgroup, 14 (51.9%) showed ultrasonographic images compatible with a fatty liver. One worker (1.4%) in the NEHC group showed hTAMSemia and ultrasonography compatible with fatty liver. The environmental levels of BTX during the 9 months of the study remained below the maximum values permitted by law in Argentina (benzene, 1.5 ppm., toluene 10 ppm and xylene 18.5 ppm). The odds ratio of developing hTAMSemia in the EHC group was 27.7 (p = 0.002).
Conclusions: Occupational exposure to aromatic hydrocarbons may cause liver damage. The liver is more vulnerable to these hydrocarbons than bone marrow. These conclusions would argue for a modification of the environmental regulations currently in force within the petroleum refineries in Argentina.