Observation of changes in urinary excretion of thorium in humans following ingestion of a therapeutic soil.
The study investigated the changes in urinary thorium excretion by humans following ingestion of a therapeutic soil, which contains about 10 ppm of thorium. This well-known healing earth in Germany has been considered as an alternative medicine for diarrhoea and gastric hyper-acidity. Six adult volunteers ingested this therapeutic soil in varying quantities for 1-15 days at levels approximating those described in the package insert of the medicine (10-60 g of soil per day). The subjects ingested about 0.1-0.6 mg of thorium daily, which is 100-600 times higher than the normal daily intake of about 1 microg thorium in Germany. All 24-h urine samples collected from the subjects during pre-ingestion, ingestion and post-ingestion periods of the soil were analyzed for (232)Th using inductively coupled plasma mass spectrometry (ICP-MS). The measured excretion values varied in a wide range. Apparently, the high thorium amounts administered did not increase the (232)Th excretion in urine as expected, suggesting that this soil ingestion will not result in a considerably higher and harmful uptake of thorium into the human body.
Höllriegl
V
V
Institute of Radiation Protection, GSF-National Research Center for Environment and Health, Ingolstädter Landstrasse 1, D-85764 Neuherberg, Germany. vera.hoellriegl@gsf.de
Greiter
M
M
Giussani
A
A
Gerstmann
U
U
Michalke
B
B
Roth
P
P
Oeh
U
U
D000284:Administration, Oral; D000328:Adult; D004784:Environmental Monitoring; D005260:Female; D005858:Germany; D006801:Humans; D008297:Male; D008875:Middle Aged; D012987:Soil; D012990:Soil Pollutants, Radioactive / Q000493:pharmacokinetics / Q000627:therapeutic use / Q000652:urine*; D013910:Thorium / Q000493:pharmacokinetics / Q000627:therapeutic use / Q000652:urine*
D012987:Soil; D012990:Soil Pollutants, Radioactive; D013910:Thorium