The Relationship of Methylated Arginines with Urine Cadmium Levels.

BACKGROUND: In this study, we aimed to show that methylated arginines are the predictors of non-clinical atherosclerotic cardiovascular complications in metal workers exposed to Cd. METHODS: The 80 Cd-exposed metal workers and 80 non-exposed workers (control) included in the study were available for measuring arginine, ADMA, SDMA, and L-NMMA levels. RESULTS: The average urine Cd levels (CdU) found were 1.03 ± 0.8 µg/g creatinine (0.84 ± 0.65 µg/L) ranging from 0.01 to 3.00 µg/g creatinine in the control group and 5.41 ± 5.2 µg/g creatinine (4.29 ± 3.81 µg/L) ranged from 0.11 to 27.2 µg/g creatinine in metal workers. On the other hand, the median ratios of the different groups (exposed and control) were found to be 449.35 and 483.88 for arginine/ADMA and 1.28 and 1.33 SDMA/ADMA, respectively. CONCLUSIONS: The present study was undertaken to investigate the relationship between cadmium exposure and methylated arginines such as ADMA/SDMA/L-NMMA parameters which is important for the early detection atherosclerotic cardiovascular diseases.

Evaluation of Erectile Dysfunction and Left Ventricular Diastolic Parameters in Lead Exposed Workers.

BACKGROUND: Lead exposure causes a wide range of vascular diseases through oxidative stress, sympathetic hyperactivity and impairment in nitric oxide bioavailability. In this study, the association between the effects of lead exposure on left ventricular diastolic indices and erectile function were assessed. METHODS: A total of 94 lead-exposed workers without known cardiovascular diseases or risk factors and 30 healthy subjects were enrolled. Systolic and diastolic functions were measured using transthoracic echocardiography. All participants were non-smokers. The International Index of Erectile Function Questionnaire (IIEF-5) was used to diagnose and grade erectile dysfunction (ED). Echocardiographic parameters, IIEF-5 score and blood lead level (BLL) were analyzed. RESULTS: The mean age and median BLL were 32.3 ± 6.4 years and 19 µg/dL in the workers, respectively. Sixty-five (69.1%) workers and 9 control subjects (30%) had ED. The IIEF-5 score was lower in the workers (17.0 ± 6.1) than in the controls (22.7 ± 2.1). In the workers, E and e' waves and E/A ratio were lower, and A wave, E/e' ratio, and left atrial volume index (LAVI) were higher than in the controls. Additionally, BLL was correlated with IIEF-5 score, e' wave, and E/e' ratio. IIEF-5 score was correlated with e' wave, E/e' ratio and LAVI. BLL was an independent risk factor for a decreased e' wave and IIEF-5 score and increased E/e' ratio in the lead-exposed workers. CONCLUSIONS: Impairment of diastolic and erectile functions, despite a younger age and in the absence of accompanying risk factors, was correlated with increased BLL.

Assessment of DNA damage in ceramic workers.

It is known that ceramic workers are potentially exposed to complex mixture of chemicals such as silica, inorganic lead, lime, beryllium and aluminum that can be associated with an increased risk of several diseases. All operations in the ceramic industries such as mixing, moulding, casting, shaking out and finishing jobs, have been associated with the higher exposure levels and in most of the silica-related industries, average overall exposure exceeded permissible exposure levels for respirable crystalline silica. The aim of this study was to evaluate the possible genotoxic damage in ceramic workers exposed to complex mixture of chemicals mainly crystalline silica. For this purpose, the blood and buccal epithelial cell samples were taken from the ceramic workers (n = 99) and their controls (n = 81). The genotoxicity was assessed by the alkaline comet assay in isolated lymphocytes and whole blood. Micronucleus (MN), binucleated (BN), pyknotic (PYC), condensed chromatin (CC), karyolytic (KYL), karyorrhectic (KHC) and nuclear bud (NBUD) frequencies in buccal epithelial cells and plasma 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) levels were also evaluated. In the study, 38 workers were diagnosed with silicosis, 9 workers were suspected to have silicosis, whereas 52 workers were found to be healthy. DNA damage in blood and lymphocytes; MN, CC + KHC, PYC frequencies in buccal epithelial cells and 8-oxodG levels in plasma were increased in workers compared to their controls. These results showed that occupational chemical mixture exposure in ceramic industry may cause genotoxic damage that can lead to important health problems in the workers.

Comprehensive Electrocardiographic Analysis of Lead Exposed Workers: An Arrhythmic Risk Assessment Study.

BACKGROUND: To evaluate electrocardiographic parameters which are related with atrial and ventricular arrhythmias measured from 12-lead surface electrocardiogram (ECG) in workers occupationally exposed to lead. METHODS: Sixty lead-exposed workers and 60 healthy controls were enrolled. Twelve-lead surface ECG was recorded and measurements of P wave durations (Pmax, Pmin) and P wave dispersion (PWD), QT durations and dispersion (QTd), corrected QT (QTc), Tp-e interval, and Tp-e/QT ratio were analyzed. RESULTS: The lead-exposed and control groups were similar with respect to baseline demographic, laboratory, and transthoracic echocardiographic indices. PWD (26.3 ± 9.7 vs 22.0 ± 9.0 ms, P = 0.014), Pmin (89.9 ± 13.8 vs 79.2 ± 10.1 ms, P < 0.001), and Pmax (116.2 ± 15.0 vs 101.2 ± 14.2 ms, P < 0.001), QT maximum (377.0 ± 27.6 vs 364.9 ± 28.5 ms, P = 0.02), QTd (38.4 ± 16.5 vs 30.5 ± 12.4 ms, P = 0.004), Tp-e interval (78.9 ± 16.5 vs 70.3 ± 14.5 ms, P = 0.003), and Tp-e/QT ratio (0.22 ± 0.04 vs 0.20 ± 0.04, P = 0.013) were significantly higher in lead-exposed workers. QT minimum and QTc values did not differ significantly. QT maximum, QTd, and Tp-e/QT ratio were correlated with urine lead level and Tp-e interval was correlated with both blood and urine lead levels. CONCLUSIONS: Lead-exposed workers have a higher risk for atrial and ventricular arrhythmias even without overt cardiac diseases compared with healthy subjects. These workers should be followed closely for adverse cardiovascular outcomes especially arrhythmias.

Assessment of heart rate response to exercise and recovery during treadmill testing in arsenic-exposed workers.

BACKGROUND: Arsenic exposure is associated with various cardiovascular diseases. The aim of the present study was to assess cardiac autonomic function via heart rate response to exercise and recovery period of treadmill testing in arsenic-exposed workers. METHODS: Sixty-five (65) occupationally arsenic-exposed workers and 35 healthy controls were enrolled. Blood and urinary arsenic levels were analyzed and symptom limited maximal treadmill exercise test were performed. Chronotropic response to exercise including age-predicted maximal heart rate (APMHR), heart rate reserve (HRreserve ), age-predicted HRreserve (APHRreserve ) and adjusted HRreserve and 1st-, 2nd-and 3rd-min heart rate recovery (HRR) indices were calculated. RESULTS: Baseline clinical and echocardiographic parameters, exercise test duration, resting and maximal heart rate, peak exercise capacity, HRreserve , APMHR, APHRreserve , and adjusted HRreserve were found to be similar between groups. HRR1 (22.0 ± 4.3 vs. 24.3 ± 3.1 bpm, p = .003) and HRR2 (43.2 ± 6.2 vs. 46.7 ± 6.4 bpm, p = .012) were significantly lower in arsenic-exposed workers compared to controls. Blood and urinary arsenic levels negatively correlated with HRR1 (r = -.477, p < .001 and r = -.438, p < .001, respectively) and HRR2 (r = -.507, p < .001 and r = -.412, p < .001 respectively). CONCLUSIONS: Arsenic-exposed workers had lower HRR indices than normal subjects but chronotropic response were similar. Cardiac autonomic dysregulation may be one of the cardiovascular consequences of arsenic exposure.

Effects of Occupational Silica Exposure on OXIDATIVE Stress and Immune System Parameters in Ceramic Workers in TURKEY.

Silica is the second most common element after oxygen, and therefore, exposures to crystalline silica dust occur in a large variety of occupations such as metal foundries, constructions, and ceramic, quarry, and pottery industries. Since crystalline silica exposure has been linked with silicosis, lung cancer, and other pulmonary diseases, adverse effect attributed to this element has be a cause for concern worldwide. Silica dust exposure in workers is still considered to be important health problem especially in developing countries. The aim of the study was to investigate the effects of occupational silica exposure on oxidative stress parameters including the activities of superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx), and levels of total glutathione (GSH) and thiobarbituric acid reactive substance (TBARS) as well as immune system parameters such as interleukin (IL)-1α, IL-1ß, IL-2, IL-4, IL-6, and IL-10 and tumor necrosis factor (TNF)-α in Turkish ceramic workers. In this study, nearly 50% of Turkish ceramic workers were diagnosed with silicosis. Eighty-four percent of these silicotic workers were found to present with profusion category 1 silicosis, whereas controls (n = 81) all displayed normal chest radiographs. Data demonstrated a significant decrease in levels of GSH and activities of CAT, SOD, and GPx, but a significant increase in MDA levels and activity of GR in all workers. Further, workers possessed significantly higher levels of IL-1α, IL-1ß, IL-2, IL-4, IL-6, IL-10, and TNF-α. These observations suggest that ceramic workers may have impaired antioxidant/oxidant status and activated immune system indicative of inflammatory responses.

Dynamic disulfide/thiol homeostasis in lead exposure denoted by a novel method.

Lead is a toxic heavy metal, and prevention of human exposure to lead has not been accomplished yet. The toxicity of lead is continually being investigated, and the molecular mechanisms of its toxicity are still being revealed. In this study, we used a novel method to examine thiol (SH)/disulfide homeostasis in workers who were occupationally exposed to lead. A total of 80 such workers and 70 control subjects were evaluated, and their native and total SH values were measured in serum using a novel method; their blood lead levels were also assessed. The novel method used for SH measurements was based on the principle of measuring native SH, after which disulfide bonds were reduced and total SHs were measured. These measurements allowed us to calculate disulfide amounts, disulfide/total SH percent ratios, disulfide/native SH percent ratios, and native SH /total SH percent ratios. We found that disulfide levels were significantly higher in workers who were exposed to lead (21.08(11.1-53.6) vs. 17.9(1.7-25), p < 0.001). Additionally, the disulfide/native SH and disulfide/total SH percent ratios were higher in exposed workers, while the native SH/total SH percent ratios were higher in the control subjects. Furthermore, the lead and disulfide levels showed a positive correlation, with p < 0.001 and a correlation coefficient of 0.378. Finally, the novel method used in this study successfully showed a switch from SH to disulfide after lead exposure, and the method is fully automated, easy, cheap, reliable, and reproducible. Use of this method in future cases may provide valuable insights into the management of lead exposure.

Arsenic related hearing loss in miners.

PURPOSE: Arsenic is a toxic metalloid that carries number of potential risks to human health, although there is little evidence of the ototoxic effect of arsenic. The aim of this study was to identify the relationship between arsenic exposure and hearing loss by measuring blood arsenic concentrations and hearing among miners. MATERIALS AND METHODS: This research is a retrospective case control study. Included in the study were miners employed in a single silver mine whose blood arsenic concentrations were high. A comparison was made on the pure tone audiometry measurements taken from miners exposed only to arsenic (Group 1), those exposed to both arsenic and noise (Group 2) and a control group exposed to neither arsenic nor noise (Group 3). RESULTS: It was found that for both ears at all frequencies, the hearing level of Group 3 was better than the hearing levels of both Group 1 and Group 2. There was no correlation between the blood arsenic levels and hearing levels in both ears. CONCLUSION: This study has revealed the ototoxic effects of arsenic. As blood arsenic concentrations do not reflect long-term exposure, no correlation was identified between blood arsenic concentrations and hearing levels. Further studies will be needed to clarify the mechanisms involved in the effect of arsenic on hearing. This paper represents the largest study to date focusing on the isolated effects of arsenic on hearing through the use of a clinical auditory test.

Assessment of the Cardiac Autonomic Nervous System in Mercury-Exposed Individuals via Post-Exercise Heart Rate Recovery.

OBJECTIVE: The aim of this study was to assess exercise heart rate recovery (HRR) indices in mercury-exposed individuals when evaluating their cardiac autonomic function. SUBJECTS AND METHODS: Twenty-eight mercury-exposed individuals and 28 healthy controls were enrolled. All the subjects underwent exercise testing and transthoracic echocardiography. The HRR indices were calculated by subtracting the first- (HRR1), second- (HRR2) and third-minute (HRR3) heart rates from the maximal heart rate. The two groups were evaluated in terms of exercise test parameters, especially HRR, and a correlation analysis was performed between blood, 24-hour urine and hair mercury levels and the test parameters. RESULTS: The mercury-exposed and control groups were similar in age (37.2 ± 6.6 vs. 36.9 ± 9.0 years), had an identical gender distribution (16 females and 12 males) and similar left ventricular ejection fractions (65.5 ± 3.1 vs. 65.4 ± 3.1%). The mean HRR1 [25.6 ± 6.5 vs. 30.3 ± 8.2 beats per min (bpm); p = 0.009], HRR2 (43.5 ± 5.3 vs. 47.8 ± 5.5 bpm; p = 0.010) and HRR3 (56.8 ± 5.1 vs. 59.4 ± 6.3 bpm; p = 0.016) values were significantly lower in the mercury-exposed group than in the healthy controls. However, there were no significant correlations between blood, urine and hair mercury levels and exercise test parameters. CONCLUSIONS: Mercury-exposed individuals had lower HRR indices than normal subjects. In these individuals, mercury exposure measurements did not show correlations with the exercise test parameters, but age did show a negative correlation with these parameters. Therefore, cardiac autonomic functions might be involved in cases of mercury exposure.

Evaluation of bone mineral density and 25-hydroxyvitamin D levels in subjects with silica exposure.

OBJECTIVE: The purpose of the study was to evaluate the bone mineral density (BMD) and 25-hydroxyvitamin D (25(OH)D) levels in patients with silica exposure. MATERIALS AND METHODS: The study included 104 male subjects with silica exposure and 36 healthy subjects. Posterior-anterior radiographs were classified according to the International Labour Office (ILO) Classification. Category 0 patients were classified as Group I (n = 54), category I patients were classified as Group II (n = 25), Category II and III patients were classified as Group III (n = 25). RESULTS: Femoral neck BMD values were significantly lower in Group III (p = 0.007). Lumbar vertebrae BMD values were significantly lower in all groups with silica exposure than in the control group (p = 0.000). The osteoporosis rate was significantly higher in Group III (p = 0.000). Subjects with silica exposure were determined to have diminished 25(OH)D levels (p = 0.012). CONCLUSION: The results of this study demonstrated that subjects with silica exposure have diminished BMD and 25(OH)D levels.

Exposure to mercury among dental health workers in Turkey: correlation with amalgam work and own fillings.

PURPOSE: To investigate the current status of exposure to mercury (Hg) among dental health workers in Turkey. METHODS: A total of 115 persons working in the same hospital were included in the study and were divided into three groups. Group 1 consisted of 67 dentists; group 2 consisted of 21 dental personnel who work with amalgam, and group 3 consisted of 27 control subjects who work in the same hospital but are non-dental personnel. The number of amalgam fillings that have been made by the dentists and the number of own fillings of the subjects were recorded. RESULTS: Plasma Hg levels were found to be 3.76 ± 1.84, 3.54 ± 1.83, and 2.69 ± 0.97 µg/L in groups 1, 2, and 3, respectively. Hg concentrations in group 1 were significantly higher than the control group. There was no significant difference between groups 1 and 2. The number of amalgam fillings made by the dentists in the previous year correlated significantly with plasma Hg levels (r = 0.378, p < 0.01). There was no significant correlation between the own amalgam fillings in the teeth of the subjects and Hg levels. CONCLUSION: Preventive measures for protection from exposure to Hg are necessary for occupational health in dentistry and proper industrial hygiene rules should be emphasized to avoid contamination during work.

Lead exposure is a risk for worsening bone mineral density in middle-aged male workers.

OBJECTIVE: Lead exposure linked to osteoporosis in women. However, there is no direct evidence whether lead exposure has effects on bone metabolism in middle-aged male subjects. Therefore, the present study investigated the relationship between bone mineral densitometry measurements, bone markers, endocrine hormones and blood lead levels. MATERIAL AND METHODS: The present study included lead exposure patients (n: 30) and control subjects (n: 32). We recorded information on patient demographics and risk factors of osteoporosis. Blood lead levels were evaluated using Varian AA 240Z atomic absorption spectrophotometry. Bone mineral density measurements were measured using dual-energy X-ray absorptiometry. RESULTS: Each lumbar T and Z scores in the lead exposure group were lower than the control group. There were no significant differences in femur neck and femur total T and Z scores between two groups. Blood lead levels were also negatively correlated with lumbar 2-4 T score, total lumbar T score, lumbar 2-4 Z score and total lumbar Z score. Urinary hydroxyproline and urinary deoxypyridinoline levels in the lead exposure group were significantly higher compared to controls. Blood lead levels were strong, positively correlated with urinary deoxypyridinoline. Endocrine hormone levels and 1,25-dihydroxy-vitamin D3 levels were comparable between lead exposure and control group. CONCLUSION: Lead exposure in male workers is an important factor for deterioration in bone mineral density. We should be screening blood lead levels and history of lead exposure in male osteoporosis.

Arsenic exposure associated with decreased bone mineralization in male.

OBJECTIVE: Arsenic (As) exposure may cause several medical problems. There were a few studies investigated whether it has affected bone tissue in women. However, there was no study in men. The aim of this study was to evaluate associations between bone mineral density (BMD) and As exposure in men subjects. MATERIAL AND METHODS: We enrolled in this study 254 subjects who due to chronic As exposure suspected and 82 subjects as a control group. Hair As levels were detected by a hair analysis (Varian AA240Z Zeeman Atomic Absorption Spectrometer, USA). BMD measurements were obtained using dual-energy X-ray absorptiometry instrumentation. We investigated associations between the hair As levels and BMD measurements. RESULTS: The frequency of osteoporosis and osteopenia was found to be 0.8% and 54.5%, respectively, in the As exposure group. The frequency of osteoporosis was found to be 1% and osteopenia was 32.4% in control subjects. There was significant difference between two groups (p < 0.001). Hair As level has a median 1.01 (min: 0.06 and max: 25.71). There were no significant correlation between hair As levels and BMD measurements. CONCLUSION: According to our observations, As exposure was associated with bone metabolism. Possible cause of osteopenia may be exposure to As. Further investigations are needed to estimate the relationship between As and bone metabolism.

Prolactin levels in manganese-exposed male welders.

PURPOSE: Early studies on manganese (Mn) exposure have demonstrated that this transition metal affects dopamine neurotransmission. Dopamine serves as a tonic inhibitor of prolactin release in the anterior hypophysis. Our aim was to determine the relation between serum prolactin levels and manganese-exposure. METHODS: Whole blood was collected from 95 non-exposed control subjects and 179 manganese-exposed male welders. Whole blood manganese was analyzed by Inductively Coupled Plasma--Mass Spectrometer on Agilent 7700 (Agilent Technologies, USA). Serum prolactin levels (PRL), aspartate transaminase (AST), alanine transaminase (ALT), urea, creatinine, soduim (Na), potassium (K) were analyzed by immunological and spectrophotometric methods on Roche E170 Modular System (Roche Diagnostics, Mannheim, Germany). RESULTS: The mean ages for control and manganese-exposed group were 40.5 ± 7.8 and 39.5 ± 8.7, respectively (p = 0.258). The mean working period (years) for control and manganese-exposed group were 17.4 ± 9.8 and 18.2 ± 7.7 years, respectively (p = 0.581). Serum AST and potassium levels were significantly higher in control group than manganese-exposed group (p = 0.002 and p = 0.048, respectively) and body-mass index (BMI) was significantly lower in control group than manganese-exposed group (p = 0.033). There was a significantly positive correlation between whole blood manganese levels and serum prolactin (r = 0.860, p < 0.001). Serum ALT levels were positively correlated with serum AST, urea and sodium (r = 0.315, p < 0.001; r = 0.121, p = 0.046; r = 0.130, p = 0.031). CONCLUSIONS: Serum prolactin level is a diagnostic marker for determining the effect of manganese-exposure.

Lymphocyte DNA damage in Turkish asphalt workers detected by the comet assay.

Asphalt has a highly complex structure and it contains several organic compounds including polycyclic aromatic hydrocarbons and heterocyclic compounds. In this study, comet assay was used to detect the DNA damage in blood lymphocytes of 30 workers exposed to asphalt fumes and 30 nonexposed controls. This is the first report on Turkish asphalt workers' investigated DNA damage using the alkaline single cell gel electrophoresis (SCGE). The DNA damage was evaluated by the percentage of DNA in the comet tail (% tail DNA) for each cell. According to our results, workers exposed to asphalt fumes had higher DNA damage than the control group (p < 0.01). The present study showed that asphalt fumes caused a significant increase in DNA damage and the comet assay is a suitable method for determining DNA damage in asphalt workers.

Acute mercury poisoning among children in two provinces of Turkey.

Elemental mercury exposure occurs frequently and is potentially a toxic, particularly in children. Children are often attracted to elemental mercury because of its color, density, and tendency to form beads. Clinical manifestations of elemental mercury intoxication vary depending on its form, concentration, route of ingestion, and the duration of exposure. We present data on 179 pediatric cases of elemental mercury poisoning from exposure to mercury in schools in two different provinces of Turkey. Of all patients, 160 children had both touched/played with the mercury and inhaled its vapors, while 26 children had only inhaled the mercury vapor, two children reported having tasted the mercury. The median duration of exposure was 5 min (min 1-max 100), and 11 (6 %) children were exposed to the mercury for more than 24 h at home. More than half of the children (51.9 %) were asymptomatic at admission. Headache was the most common presenting complaint. The results of physical and neurological examinations were normal in 80 (44.6 %) children. Mid-dilated/dilated pupils were the most common neurological abnormality, and this sign was present in 90 (50.2 %) children. Mercury levels were measured in 24-h urine samples daily, and it was shown that the median urinary level of mercury was 29.80 µg/L (min, 2.40 µg/L; max, 4,687 µg/L). A positive correlation was also found between the duration of exposure and urinary mercury levels (r = 0.23, p = 0.001). All patients were followed up for 6 months. On the first follow-up visit performed 1 month after discharge, the neurological examinations of all patients were normal except for those patients with peripheral neuropathy and visual field defects. On the last follow-up visit at the sixth month, only two children still experienced visual field defects. In conclusion, this study is one of the largest case series of mercury intoxication of students in schools. Elemental mercury exposure can be potentially toxic, and its symptomatology is variable, particularly in children. Therefore, school staff and children should be aware of the risk of mercury toxicity. Pediatricians also need to warn parents and children about the hazards of playing with any chemical.

Oxidative Stress Parameters, Selenium Levels, DNA Damage, and Phthalate Levels in Plastic Workers.

Di(2-ethylhexyl)phthalate (DEHP) is the most widely used phthalate. DEHP is highly used in PVC floorings and PVC windows and carpeting. The objective of this study was to determine sex hormone levels, oxidative stress parameters, selenium levels, DNA damage, and phthalate levels in plastics workers (n = 24, age = 20-58 years) working in the production of rubber mechanical goods and exposed to DEHP in workplace. The control group (n = 29, age = 25-54, all male) was selected from age-matched healthy adults. Antioxidant parameters and DNA damage were determined by spectrophotometry. Selenium levels were determined by atomic absorption spectroscopy. Plasma hormone levels were measured by chemiluminescence microparticle immunoassay. Plasma phthalate levels were determined by high-pressure liquid chromatography. Plastic workers had lower serum testosterone and free T4 levels and higher follicle-stimulating hormone levels vs. controls. Liver enzyme activities were markedly higher in workers vs. controls. There were also increases in plasma glutathione peroxidase levels and marked decreases in plasma selenium and erythrocyte total glutathione levels in plastics workers (P < 0.05 vs. control). Plasma 8-hydroxy-2'-deoxyguanosine levels were 14-fold higher in plastics workers than in controls. Plasma DEHP and mono(2-ethylhexyl)phthalate were also markedly higher in workers vs. controls. The results of this study show that occupational exposure to DEHP may lead to disturbances in sex hormones, increased liver problems, higher oxidative stress and DNA damage levels, and lower trace element concentrations in workers. More comprehensive and mechanistic studies with higher numbers of subjects are needed to show the unwanted effects of occupational exposure to DEHP.

Assessment of DNA damage in welders using comet and micronucleus assays.

Welding technology is widely used in pressurized containers, thermal power plants, refineries, chemical facilities and steel structures. Welders are exposed to a number of hazardous compounds such as ultraviolet (UV) radiation, electromagnetic fields, toxic metals and polycyclic aromatic hydrocarbons (PAHs). In the present study, 48 welders and an equal number of control subjects were evaluated for DNA damage in the whole blood and isolated lymphocytes using the comet assay. The genotoxic damage in buccal epithelial cells of subjects was determined by micronucleus (MN) assay. Metal(loids) such as Cr, Mn, Ni, Cu, As, Cd and Pb levels in blood samples were evaluated by using Inductively Coupled Plasma-Mass Spectrometer (ICP-MS). Results of this study showed that DNA damage in blood, isolated lymphocytes, and buccal epithelial cells were significantly higher in workers compared to the controls. Also, these workers had remarkably higher blood Cr, Cu, Cd, Ni and Pb levels. These results showed that occupational exposure to welding fumes may cause genotoxic damage that can lead to important health problems in the workers. More extensive epidemiological studies should be performed that enable the assessment of health risk in welding industry.