Mercury in traditional Tibetan medicine - panacea or problem?

UNLABELLED 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 II). 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 microg, estimated as 10 microg/kg per day. (Established reference dose for chronic oral exposure: 0.3 microg/kg per day.) Blood mercury levels were non-detectable, but mean urinary mercury levels for Group I were 67 microg/L (EPA levels <20 microg/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.