Hydrocarbons and Kidney Damage: Potential Use of Neutrophil Gelatinase-Associated Lipocalin and Sister Chromatide Exchange

Abstract

Background: Millions of workers are exposed to polycyclic aromatic hydrocarbons (PAHs) and it is known that the kidney is a target for toxic chemicals. We have evaluated neutrophil gelatinase-associated lipocalin (NGAL) as a potential marker of tubular damage and have used it, with sister chromatid exchange (SCE) analysis, to evaluate carcinogenic risk in a group of workers from an oil refinery. Methods: NGAL and SCE analysis were evaluated in 160 subjects. Exposed subjects were divided into three groups, according to levels of exposure to PAHs: 40 highly exposed workmen (WM), 40 less exposed office workers (OW), and 40 subjects (GE) living in Gela. The control group included 40 healthy subjects (HS). Results: WM, OW and GE showed higher NGAL levels than HS. WM had higher levels of NGAL than the OW and GE groups; in ROC analysis, serum NGAL showed a good diagnostic profile (sensitivity 87.5%; specificity 100.0%), as did urinary NGAL (sensitivity 90.0%; specificity 92.5%). Moreover, regarding SCE analysis, WM showed higher values than HS. A direct correlation between SCE and serum NGAL was found in WM, the group most exposed to PAHs. Conclusion: The high values of NGAL are an expression of damage to the renal tubule determined by exposure to PAHs. Compared to the other groups studied, chromosomal aberrations – expressed as SCE – were increased in WM, the group most exposed to PAHs, indicating genotoxic damage. NGAL may also play a role in the process of carcinogenesis having a direct correlation with the number of SCEs.