[Liver damage in workers exposed to hydrocarbons]. / Daño hepático en trabajadores expuestos a hidrocarburos.

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.

Daño hepático en trabajadores expuestos a hidrocarburos / Liver damage in workers exposed to hydrocarbons

Fundamento y objetivos: Investigar la presencia de hipertransaminasemia, como expresión bioquímica de daño hepático, y correlacionarla con la exposición a hidrocarburos (benceno, tolueno y xileno BTX) en trabajadores de una empresa petroquímica. Pacientes y método: Se revisaron las historias clínicas de 167 empleados, 95 expuestos (GE) y 72 no expuestos (GNE), y se evaluaron los siguientes parámetros: edad, sexo, antigüedad laboral, índice de masa corporal y pruebas bioquímicas. Se excluyó a los que presentaban hepatopatía previa, diabetes mellitus o ingesta de alcohol > 50 g/día. En los que se halló hipertransaminasemia se realizaron las siguientes pruebas: proteinograma, protrombina, anti-HBc, HBsAg, anti-VHC y ecografía hepática. Tres operarios comprendidos en el GE fueron excluidos, 2 por presentar marcadores séricos de virus de hepatitis B y otro por haber decidido no participar en el estudio; en definitiva, el GE quedó constituido por 92 trabajadores. Se midieron los contaminantes ambientales. Resultados: Veintisiete individuos del GE (29,4%) y uno del GNE (1,4%) presentaron hipertransaminasemia (p = 0,001). El resto de las pruebas bioquímicas, hemograma y de los otros parámetros analizados no mostraron diferencias entre ambos grupos. Iguales parámetros se evaluaron entre GE1 (ALAT normal) y GE2 (elevada) sin hallarse diferencias. En la ecografía se halló compatibilidad con hígado graso en 14 (51,9%) de los 27 pacientes del GE2. Un individuo (1,4%) del GNE presentó alanino-aminotransferasa elevada y ecografía compatible con hígado graso. Los valores de compuestos orgánicos volátiles ambientales resultaron inferiores a las 5 ppm exigidas durante los 9 meses que duró el estudio (benceno 1,5 ppm, tolueno 10 ppm, y xileno 18,5 ppm). La odds ratio para desarrollar hipertransaminasemia en el GE fue de 27,7 (p = 0,002). Conclusiones: La exposición laboral a hidrocarburos volátiles puede ocasionar daño hepático. El hígado, según nuestros hallazgos, aparece como más vulnerable a los hidrocarburos volátiles que la médula ósea. Estas conclusiones deberían servir para modificar las normas de tolerabilidad ambiental vigentes en las refinerías de Argentina

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