Toxic metal content in 52 frequently prescribed herbal medicines on the Korean market.

This study was conducted to investigate the toxic metal content (Pb, As, Cd and Hg) of 52 frequently prescribed herbal medicines and to identify herbal medicines that exceed the Korea Food and Drug Administration (KFDA) maximum limits. A total of 3534 samples, including 1966 domestic samples and 1568 imported samples, were analysed using an Inductively Coupled Plasma-Mass Spectrometer (ICP-MS). Total amounts of Pb, As, Cd and Hg were significantly different between domestic (0.

A ten-year survey of Giardia cysts in drinking water supplies of Seoul, the Republic of Korea.

To understand the distribution of Giardia cysts in drinking water supplies in Seoul, Korea, we collected water samples quarterly at 6 intakes in the Han River, its largest stream and 6 conventional water treatment plants (WTPs) serving drinking water, from 2000 to 2009. Giardia cysts in each of 10 L water were confirmed in 35.0% of intake water samples and the arithmetic mean was 1.

Inactivation of environmental mycobacteria by free chlorine and UV.

The resistance of environmental mycobacteria (EM) against chlorine and ultraviolet (UV) was evaluated for determination of the Ct value and UV dose to inactivate EM. Chlorine disinfection experiments were done on Mycobacterium fortuitum in oxidant demand-free buffered water at the worst condition (pH 8.5, 4 degrees C) and normal condition (pH 7.