Objective: To investigate trace elements in liquid homeopathic preparations and the influence of container material, storage duration, and potentisation.
Materials and methods: Using inductively coupled plasma-mass spectroscopy (ICP-MS), we investigated (a) aqua bidestillata (ABD) stored for 12 h in either brown glass or high density polyethylene (HDPE) bottles; (b) ABD stored for 2 h in HDPE, the same additionally filled in brown glass bottle, and ABD potentised in brown glass up to C30; (c) -- at 3 different sample ages and with statistical analysis -- ABD C30 (brown glass), AgNO3 C30 (brown glass), and controls (unsuccussed, brown glass and HDPE).
Results: Contamination of the initial ABD increased and element concentrations changed far more when stored in brown glass bottles than in HDPE. Effects were strongest during initial storage time and during the first potentisation step from mother tincture to C1; subsequent potentising steps produced no relevant changes. Potencies of AgNO3 and potencies of water contained similar contamination.
Conclusions: Potentising accelerates material exchange between container and solvent, mostly during succussion. Research on potentised preparations should use potentised controls with equal preparation and storage time. If physical and biological effects of potencies exist, contaminants might be one factor for their generation.