Arsenic, cadmium, mercury, and lead levels in hair and urine in first-year RUDN University students of different geographic origins.

The objective of the present study was to assess the markers of arsenic, cadmium, mercury, and lead exposure in first-year RUDN University students of different geographic origins. A total of 274 first-year students of the RUDN University originating from Russia (n = 65), Asia (n = 57), Middle East (n = 84), Africa (n = 40), and Latin America (n = 28) were enrolled in the present study. Evaluation of As, Cd, Hg, and Pb levels in urine and hair was performed using inductively coupled plasma-mass spectrometry. The obtained data demonstrate that hair As levels in foreign students exceed that in Russian examinees. The highest Cd and Pb levels were detected in subjects from Africa and Latin America, whereas hair Hg content was significantly higher in Latin America students. Urinary Cd levels in foreign students exceeded those in Russian counterparts. In turn, the highest Hg concentration in urine was revealed in students originating from Middle East and especially Latin America. Urinary Pb levels were found to be the highest in students from Africa. Multiple regression analysis demonstrated that Asian, African, and Latin American origins were considered as a significant predictor of hair Hg content. Higher urinary Hg levels were associated with Asia, Middle East, and Latin American origins. Prior habitation in Africa and Asia was considered as predictor of higher hair Pb and urinary Cd levels. The observed difference may be indicative of geographic difference in toxic metal exposure patterns.

Mechanism of electroreduction of the Henry reaction products. Electrochemically initiated degradation of 1-phenyl-2-nitroethanol.

Electroreduction of the Henry reaction product - i.e. 1-phenyl-2-nitroethanol (PNE) - in 0.1 M Bu(4)NClO(4) solution in MeCN has been investigated by a set of experimental (cyclic voltammetry, chronoamperometry, and controlled potential electrolysis) and theoretical (digital simulation and quantum chemical calculations) methods. The results obtained show that cathodically generated radical anion of PNE undergoes C-C bond cleavage reaction resulting in the formation of the free radical of benzyl alcohol and nitromethane anion. The proton transfer between these species affords nitromethane and benzaldehyde radical anion. Electron transfer from the last to PNE initiates the cyclic process of the PNE degradation.