Botanical dietary supplements have a long history of use in Europe and Asia, but the use of these products is becoming increasing popular in the United States. Because these products are classified as dietary supplements, the U.S. Food and Drug Administration does not routinely monitor them for environmental contaminants. Ginseng served as a model botanical dietary supplement and was purchased from suppliers in the United States, Europe, and Asia. Samples were analyzed for metals (e.g., cadmium, nickel) and chlorinated pesticides (e.g., PCNB, DDT, and metabolites). Flame and furnace atomic absorption spectrophotometry were utilized for analysis of metals, while gas chromatography (GC) and CC-mass spectrophotometry were utilized for analysis of chlorinated pesticides. Because no formalized guidelines exist to determine risk of botanical dietary supplements, U.S. Environmental Protection Agency guidelines for protection of human health were used. Metals and chlorinated organics were found in Ginseng samples, but the concentrations posed no noncarcinogenic hazard; however, a 1000 mg/d dose for 350 d/yr resulted in 1 x 10(-6) carcinogenic risk in 19% of the Ginseng samples analyzed. At a lower usage rate (42 d/yr), no samples exceeded 1 x 10(-6) risk. Chlorinated organics, such as aldrin and heptachlor epoxide, accounted for the carcinogenic risk (1 x 10(-6)) in the Ginseng samples.