Mercury in traditional Tibetan medicine - Panacea or problem?

Symptoms of mercury toxicity, biochemical changes, and blood/urine mercury levels were evaluated in a small group of patients. Six patients attending Delek Hospital, Dharamsala, India, taking mercury-containing traditional Tibetan medicine (TTM) (Group I), were compared with three patients taking non-mercury containing TTM (Group II) and healthy volunteers (Group III). Quantitative estimation of mercury ingestion based on chemical analysis was compared with US regulatory standards. Results: Group I were significantly older (mean 55 years ± SE 6.4) range 26-69 years, than Group II (26.7 years ± SE 5) range 17-34 years and Group III (32.5 years ± SE 0.5) range 33-34 years (P = 0.05). Group I took TTM on average for 51 months and had a mean of 2.5 non-specific, mercury-related symptoms. Group I had higher mean diastolic pressures (85 mmHg) than Group II (73 mmHg) (P = 0.06) and more loose teeth. Mean daily mercury intake for Group I was 674 μg, estimated as 10 μg/kg per day. (Established reference dose for chronic oral exposure: 0.3 μg/kg per day.) Blood mercury levels were non-detectable, but mean urinary mercury levels for Group I were 67 μg/L (EPA levels <20 μg/L). Renal and liver function tests were not significantly different between groups and within normal clinical range. Conclusions: Prolonged ingestion of mercury containing TTM is associated with absent blood levels, but relatively high urinary levels. Further studies are needed to evaluate toxicity and therapeutic potential.