Environ Health Perspect. 1999 Dec; 107(12): A604-5.

Medicinal herbs: NTP extracts the facts.

The National Toxicology Program (NTP) has announced that it will design and initiate studies to identify and characterize possible adverse health effects that may be associated with prolonged use or higher doses of some of the most popular medicinal herbs, including Ginkgo biloba, Echinacea angustifolia, and Panax quinquefolius (American ginseng). The NTP studies a large variety of substances to which the population may be exposed in the environment, occupationally, in the food supply, or elsewhere.