Objectives: The aim of this study is to investigate the effect of elemental mercury exposure on renal function and antioxidative enzymes activity as a possible mechanism of renal affection among dental staff. Methods: This study was performed on a group of dental staff exposed to elemental mercury (N=32) and matched control group (N=37). Urinary and blood level of mercury, albumin α1 microgloblin in urine, glutathione peroxidase and superoxide dismutase blood level were measured for the exposed and control group. Results: Compared to the control group, urinary and blood mercury were significantly higher in the exposed group. Glutathione peroxidase and superoxide dismutase activities in blood were significantly decreased and were negatively correlated with duration of work. Conclusion: Oxidative stress is an important molecular mechanism for renal dysfunction in mercury exposure, manifested by decreased activities of antioxidant enzymes.
ADA Council on Scientific Affairs (2003) Dental mercury hygiene recommendations. Association report. The Journal of the American Dental Association134: 1498-1499.
2.
Apostoli P., Colombi A., Buratti M., et al. (2002) Evaluation of the dose of mercury in exposed and control subjects. La Medicina del Lavoro93(3): 159-175.
3.
Augusti PR, Conterato GM, Somacal S., et al. (2007) Effect of lycopene on nephrotoxicity induced by mercuric chloride in rats. Basic & Clinical Pharmacology & Toxicology100(6): 398-402.
4.
Bano Y. and Hasan M. ( 1989) Mercury induced time-dependent alterations in lipid profiles and lipid peroxidation in different body organs of cat-fish Heteropneustes fossilis. Journal of Environmental Science and Health Part B24(2): 145-166.
5.
Bates MN ( 2006) Mercury amalgam dental fillings: an epidemiologic assessment . International Journal of Hygiene and Environmental Health209(4): 309-316. Epub 2006 Jan 30.
6.
Brownawell AM, Berent S., Brent RL, Bruckner JV, Doull J., Gershwin EM, et al. (2005) The potential adverse health effects of dental amalgam. Toxicological Reviews24(1): 1-10.
7.
Bulat P., Duije I., Potkonjak B., and Vidakovic A. ( 1998) Activity of glutathione peroxidase and superoxide dismutase in workers occupationally exposed to mercury. International Archives of Occupational and Environmental Health71: S37-39.
8.
De Burbure C., Buchet JP, Bernard A., et al. (2003) Biomarkers of renal effects in children and adults with low environmental exposure to heavy metals. Journal of Toxicological and Environmental Health Part A66(9): 783-798.
9.
El-Safty IA, Gadallah M., Shafik A., and Shouman AE ( 2002) Effect of mercury vapour exposure on urinary excretion of calcium, zinc and copper: relationship to alterations in functional and structural integrity of the kidney. Toxicology and Industrial Health18(8): 377-388.
10.
El-Safty IA, Shouman AE, and Amin NE ( 2003) Nephrotoxic effects of mercury exposure and smoking among Egyptian workers in a fluorescent lamp factory. Archives of Medical Research34(1): 50-55.
11.
Farahat SA, Rashed LA, Zawilla NH, and Farouk SM ( 2009) Effect of occupational exposure to elemental mercury in the amalgam on thymulin hormone production among dental staff. Toxicology and Industrial Health25(3): 159-167.
12.
Franko A., Budihna MV, and Dodic-Fikfak M. ( 2005) Long-term effects of elemental mercury on renal function in miners of the Idrija Mercury Mine. The Annals of Occupational Hygiene49(6): 521-527.
13.
Herber RF, De Gee AJ, and Wibowo AA ( 1988) Exposure of dentists and assistants to mercury: mercury levels in urine and hair related to conditions of practice. Community Dentistry and Oral Epidemiology16(3): 153-158.
14.
Heyer NJ, Echeverria D., Farin FM, and Woods JS ( 2008) The association between serotonin transporter gene promoter polymorphism (5-HTTLPR), self-reported symptoms, and dental mercury exposure . Journal of Toxicology and Environmental Health Part A71(19): 1318-1326.
15.
Jadhav SH, Sarkar SN, Aggarwal M., and Tripathi HC ( 2007) Induction of oxidative stress in erythrocytes of male rats subchronically exposed to a mixture of eight metals found as groundwater contaminants in different parts of India. Industrial Health52(1): 145-151.
16.
Jarosińska D., Horvat M., Sällsten G., et al. (2008) Urinary mercury and biomarkers of early renal dysfunction in environmentally and occupationally exposed adults: a three-country study. Environmental Research108(2): 224-232.
17.
Khan SA, Priyamvada S., Farooq N., et al. (2009) Protective effect of green tea extract on gentamicin-induced nephrotoxicity and oxidative damage in rat kidney. Pharmacological Research59(4): 254-262.
18.
Kobal AB, Horvat M., Prezelj M., et al. (2004) The impact of long-term past exposure to elemental mercury on antioxidative capacity and lipid peroxidation in mercury miners. Journal of Trace Elements in Medicine and Biology17(4): 261-274.
19.
Kobal AB, Prezelj M., Horvat M., et al. (2008) Glutathione level after long-term occupational elemental mercury exposure. Environmental Research107(1): 115-123.
20.
Langworth S., Sällsten G., Barregård L., et al. (1997) Exposure to mercury vapor and impact on health in the dental profession in Sweden. Journal of Dental Research76(7): 1397-1404.
21.
Levy M. ( 1995) Dental amalgam: toxicological evaluation and health risk assessment. Journal of the Canadian Dental Association61(8): 667-668, 671-674.
22.
Mackert JR and Berglund A. ( 1997) Mercury exposure from dental amalgam fillings: absorbed dose and the potential for adverse health effects. Critical Reviews in Oral Biology and Medicine8(4): 410-436.
23.
Miller DM, Lund BO, and Woods JS ( 1991) Reactivity of Hg(II) with superoxide: evidence for the catalytic dismutation of superoxide by Hg(II). Journal of Biochemical Toxicology6(4): 293-298.
24.
Mortada WL, Sobh MA, El-Defrawy MM, and Farahat SE ( 2002) Mercury in dental restoration: is there a risk of nephrotoxicity ? Journal of Nephrology15(2): 171-176.
25.
Patrick L. ( 2002) Mercury toxicity and antioxidants: Part 1: role of glutathione and alpha-lipoic acid in the treatment of mercury toxicity. Review. Alternative Medicine Review7(6): 456-471.
26.
Perrin-Nadif R., Dusch M., Koch C., Schmitt P., and Mur JM ( 1996) Catalase and superoxide dismutase as biomarkers of oxidative stress in workers exposed to mercury vapors. Journal of Toxicology and Environmental Health48: 107-119.
27.
Ritchie KA, Burke FJ, Gilmour WH, et al. (2004) Mercury vapour levels in dental practices and body mercury levels of dentists and controls. British Dental Journal197(10): 625-632.
28.
Roels HA, Hoet P., and Lison D. ( 1999) Usefulness of biomarkers of exposure to inorganic mercury, lead, or cadmium in controlling occupational and environmental risks of nephrotoxicity . Renal Failure21(3-4): 251-262.
29.
Schotters SB, McBride JH, Rodgerson DO, et al. (1988) Standardization for four protein analytes with the Behring Nephhelometer. Clinical Chemistry34: 1870-1872.
30.
Seppänen K., Soininen P., Salonen JT, Lötjönen S., and Laatikainen R. ( 2004) Does mercury promote lipid peroxidation? An in vitro study concerning mercury, copper, and iron in peroxidation of low-density lipoprotein . Biological Trace Element Research101(2): 117-132. Singh D., Chander V., and Chopra K. (2003) Carvedilol and trimetazidine attenuates ferric nitrilotriacetate-induced oxidative renal injury in rats . Toxicology191(2-3): 143-151. Stankiewicz A. and Skrzydlewska E. (2003) Protection against cyclophosphamide-induced renal oxidative stress by amifostine: the role of antioxidative mechanisms. Toxicology Mechanisms and Methods13(4): 301-308. Stohs SJ and Bagchi D. (1995) Oxidative mechanisms in the toxicity of metal ions. Free Radical Biology and Medicine18: 321-336.
31.
Trzcinka-Ochocka M., Gazewski A., and Brodzka R. ( 2007) Exposure to mercury vapors in dental workers in Poland . International Journal of Occupational Medicine and Environmental Health20(2): 147-153.
32.
Ukeda H., Maeda S., Ishii T., and Sawamura M. ( 1997) Spectrophotometric assay for superoxide dismutase. Analytical Biochemistry251(2): 206-209.
33.
Ursini F., Majiorino M., and Gregolin C. ( 1985) The selenoenzyme phospholipid hydroperoxide glutathione peroxidase. Biochimica et Biophysica Acta839: 62-70.
34.
Zolfaghari G., Esmaili-Sari A., Ghasempouri SM, and Faghihzadeh S. ( 2007) Evaluation of environmental and occupational exposure to mercury among Iranian dentists. Science of the Total Environment381(1-3): 59-67.
35.
Zwolińska D., Grzeszczak W., Kiliś-Pstrusińska K., Szprynger K., and Szczepańska M. (2004) Lipid peroxidation and antioxidant enzymes in children with chronic renal failure. Pediatric Nephrology19(8): 888-892.
