In a group of 40 workers occupationally exposed to arsenic (As workers) biological markers for cardiovascular diseases were studied. The median arsenic concentration in urine samples from the exposed group was 22.3 nmol of As per mmol of creatinine, while the individual maximum level was 294.5 nmol of As per mmol of creatinine. That of the reference group was 12 nmol of As per mmol of creatinine and significantly below the level of the exposed group (p < 0.001). The arsenic concentration in urine samples from colleagues of the persons working with arsenic containing products was similar to the arsenic concentration in urine samples from the As workers. The concentration of glycosylated haemoglobin (Hgb A_1C) was increased in whole blood from the As workers. The level of the As workers was 5.4% (median), similar to that of colleagues (5.5%), while that of the reference group was 4.4%. The differences were significant (p < 0.001). Multiple regression analysis showed a significant connection (p = 0.034) between the concentration of Hgb A_1C in whole blood and the arsenic level in urine from the As workers. The systolic blood pressure was 125 mm Hg in the As workers and 117 mm Hg in the control group. The difference was significant (p = 0.023). It is concluded that arsenic exposure has an influence on carbohydrate metabolism, increases the systolic blood pressure and finally may result in increased risk of development of cardiovascular diseases.