MONDAY, Sept. 17, 2018 (HealthDay News) -- The high mercury (Hg) concentration contained in traditional Tibetan medicine (TTM) could be harmful to humans and contribute to the environmental Hg burden in Tibet, according to a study published in the Aug. 7 issue of Environmental Science & Technology.
Maodian Liu, Ph.D., from Peking University in China, and colleagues investigated elevated concentrations of total mercury (THg) and methylmercury (MeHg) found in the municipal sewage in Tibet.
The researchers found that these elevated concentrations were likely related to regular ingestion of TTM that contains Hg. In 2015, 3,600 kg of THg was released from the human body into the terrestrial environment as a result of TTM ingestion in Tibet; this accounted for 45 percent of the total THg released into the terrestrial environment in Tibet. Regular TTM ingestion leads to chronic exposure to inorganic Hg (IHg) and MeHg, which was higher than from any other known dietary sources (34 to 3,000-fold and 0 to 12-fold, respectively). On application of a human physiology model, ingestion of TTM was found to induce high blood IHg and MeHg levels in the human body. For the MeHg to be cleared out of the human body and return to the initial concentration before ingestion of one TTM pill would take 180 days.
"Our analysis suggests that high Hg level contained in TTM could be harmful to human health and elevate the environmental Hg burden in Tibet," the authors write.