The current system of radiation protection for humans is based on the linear-no-threshold (LNT) risk-assessment paradigm. Perceived harm to irradiated nuclear workers and the public is mainly reflected through calculated hypothetical increased cancers. The LNT-based system of protection employs easy-to-implement measures of radiation exposure. Such measures include the equivalent dose (a biolog...

Benzene is widely distributed in the environment. The exposure scenario of most concern to the general public is low-level inhalation over long periods. This is because the general population is exposed to benzene mainly through inhalation of contaminated air, particularly in areas of heavy traffic and around gas stations, and through inhalation of tobacco smoke from both active and passive smo...

Human dental pulp cells were cultured in fluoride containing medium of various concentrations (0, 1, 2, 5, 10, 20, 25, 30, 40, 50, 60 and 80 ppm) in order to study the biological effect on the cells' proliferation and alkaline phosphatase (ALP) activities. It was found that fluoride at 5 ppm concentration significantly stimulated cell proliferation and ALP activity between 24 and 48 hours after...

background: iron, manganese, and aluminum are three abundant metals on earth and their concentrations have increased in aquatic environments as a result of natural and industrial activities. this study was undertaken to report the median acute toxicity (lc50) and accumulation of the sub-lethal concentration (10% 96-h lc50) of iron (fe), manganese (mn) and aluminum (al) in kutum (rutilus kutum) ...

background: in general, measurements of solar ultraviolet (uv) radiation are related to horizontal surfaces. while the hu­mans walking and standing outdoors expose to the natural solar uv radiation, their eyes, cheeks, extremities, trunks, or many other anatomical sites are close to vertical plane and random orient to different directions. in this study, we character­ized the diurnal variations...