Effects of Homeopathic Preparations of Mercurius corrosivus on the Growth Rate of Severely Mercury-Stressed Duckweed Lemna gibba L.

BACKGROUND: We developed a bioassay with mercury-stressed duckweed (Lemna gibba L.) to study potential effects of homeopathically potentised mercury(II) chloride (Mercurius corrosivus [Merc-c.]). The response of this bioassay to homeopathic treatments as a function of stress intensity was also of interest. METHODS: Duckweed was severely stressed with mercury(II) chloride for 48 hours. Afterwards plants grew in either Merc-c. (seven different potency levels, 24x to 30x) or water controls (unsuccussed and succussed water) for 7 days. Growth rates of the frond (leaf) area were determined using a computerised image analysis system for different time intervals between the measurements on days 0, 3 and 7. Three independent experiments with potentised Merc-c. each were evaluated. Additionally, three water control experiments were analysed to investigate the stability of the experimental set-up (systematic negative control [SNC] experiments). All experiments were randomised and blinded. RESULTS: Unsuccussed and succussed water did not significantly differ in terms of duckweed growth rate. The SNC experiments did not yield any significant effects, providing evidence for the stability of the experimental system. Data from the two control groups and the seven treatment groups (Merc-c. 24x-30x) were each pooled to increase the statistical power. Duckweed growth rates for day 0 to 3 were reduced (p < 0.05) after application of Merc-c. compared with the controls. Growth rates for day 3 to 7 were not influenced by the homeopathic preparations. CONCLUSIONS: The present test system with Lemna gibba L. that was severely stressed by mercury yielded evidence for specific effects of Merc-c. 24x to 30x, namely a growth reduction in the first time period (day 0-3). This is in contrast to former experiments with slightly arsenic-stressed duckweed, where a growth increase was observed in the second time period (day 2-6). We hypothesise that the differing results are associated with the level of stress intensity (severe versus slight).

A review of three simple plant models and corresponding statistical tools for basic research in homeopathy.

In this paper, we review three simple plant models (wheat seed germination, wheat seedling growth, and infected tobacco plants) that we set up during a series of experiments carried out from 1991 to 2009 in order to study the effects of homeopathic treatments. We will also describe the set of statistical tools applied in the different models. The homeopathic treatment used in our experiments was arsenic trioxide (As2O3) diluted in a decimal scale and dynamized. Since the most significant results were achieved with the 45th decimal potency, both for As2O3 (As 45x) and water (W 45x), we here report a brief summary of these results. The statistical analysis was performed by using parametric and nonparametric tests, and Poisson distribution had an essential role when dealing with germination experiments. Finally, we will describe some results related to the changes in variability, which seems to be one of the targets of homeopathic treatment effect.

Duckweed (Lemna gibba L.) as a test organism for homeopathic potencies.

OBJECTIVES: A bioassay with duckweed (Lemna gibba L.) was used to study the effects of homeopathic potencies on the plant's growth rate. Screening included 12 substances: argentum nitricum, copper sulfate, gibberellic acid, 3-indole acetic acid, kinetin, lactose, lemna minor, methyl jasmonate, metoxuron, phosphorus, potassium nitrate, and sulfur. Each substance was tested in the potency range 14x-30x. Controls were unsuccussed and succussed water. DESIGN: In randomized and blinded experiments, duckweed was grown in either potentized substances or water controls over 7 days. Frond (leaf) growth was measured regularly with a computerized image analysis system and growth rates were calculated for different time intervals (day 0-7, 0-3, 3-7). Additionally, a water control run with unsuccussed water as the only test substance was performed to determine the variability of the bioassay. RESULTS: For the water control run, the between-group coefficient of variance for groups of five replicates was 0.87% for the frond area-related average specific growth rate r(area) compared to 1.60% for the frond number-related average specific growth rate r(num). Thus, the former is the preferred parameter to be used. Of twelve tested substances, potentized argentum nitricum, phosphorus, and kinetin significantly (p<0.05, analysis of variance F-test) affected the main parameter: frond area-related average specific growth rate (day 0-7). Segmented area growth rates (day 0-3 or 3-7) were affected by potentized argentum nitricum, gibberellic acid, lactose, and phosphorus. CONCLUSIONS: The described experimental set-up with L. gibba as test organism appears to be a promising new model system to investigate effects of potentized substances. Yet larger sets of replication experiments with selected test substances and systematic negative controls are necessary to verify the effects found.

The effects of a 45x potency of arsenicum album on wheat seedling growth -- a reproduction trial.

BACKGROUND: Independent replications of preclinical investigations of homeopathic potencies are rare. However, they are a necessary tool to determine the relevant factors modulating the effects of homeopathic potencies in preclinical systems. OBJECTIVE: The goal of the present study was to reproduce a trial published in 1997. An Italian group of researchers investigated the effect of Arsenicum album 45x on the growth of wheat which had been previously poisoned with a material dose of Arsenicum album. The homeopathic treatment was associated with increased wheat shoot growth significantly different from the control group (+24%, p < 0.001). MATERIALS AND METHODS: Wheat poisoned with a sublethal dose of Arsenicum album was cultivated in either Arsenicum album 45x, water 45x, or unpotentized water. After 7 days, shoot length was measured. Reproducibility was assessed in eight independent experiments. RESULTS: Arsenicum album 45x significantly inhibited wheat shoot growth (-3%) compared to treatment with unpotentized water and water 45x (p = 0.011 and p = 0.037). Within the experimental series performed in this reproduction trial, the effects of Arsenicum album 45x proofed to be reproducible. The wheat seed species used did not seem to have a significant impact on the experimental outcome. CONCLUSION: The result of this replication trial is a reversal of the original study, since Arsenicum album 45x inhibited wheat shoot growth instead of enhancing it. Nevertheless, high homeopathic potencies may induce statistically significant effects in biological systems. However, the magnitude and direction of these effects seem to depend on yet unknown parameters.

A biostatistical insight into the As(2)O(3) high dilution effects on the rate and variability of wheat seedling growth.

BACKGROUND: Most criticism of homeopathy concerns the lack of scientific bases and theoretical models. Fundamental research could make important contributions to our understanding of the mechanisms of action of homeopathic treatments. Plant-based bioassays are suitable for basic research -- lacking the placebo effect and ensuring large data samples for structured statistical analyses. OBJECTIVE: The aim of this study was to reproduce a previous experiment on the effects of arsenic trioxide (As(2)O(3)) high dilutions on wheat seedling growth in order to verify whether the same significant results could be obtained working in a different place and with a different experimental team. A further goal was to investigate high dilution effects on variability. MATERIAL AND METHODS: A structured experiment was performed blind over 9 weeks, using wheat seeds previously stressed with a sublethal dose of As(2)O(3). The seeds were then treated with either potentized As(2)O(3) (5x, 15x, 25x, 35x, 45x), potentized water (equivalent potencies) or diluted As(2)O(3) (10(-5), 10(-15), 10(-25), 10(-35), 10(-45)). The working variable was the stem length, measured after 4, 5, 6 and 7 days. RESULTS: Some potencies (As(2)O(3) 45x and H(2)O 45x) induced a relevant increase in seedling growth and/or a variability decrease. Diluted As(2)O(3) did not induce any significant results. CONCLUSIONS: Confirmation of a significant stimulating effect on seedling growth and a significant decrease of variability was obtained with ultra-high dilutions at the 45x potency. The model of wheat germination and growth has been confirmed to be a good tool for basic research in homeopathy.

Statistical analysis of the effect of high dilutions of arsenic in a large dataset from a wheat germination model.

This paper describes the statistical analysis of a series of experiments using a simple biological model (wheat germination in vitro), where a large number of wheat seeds were treated with homeopathic potencies of Arsenic trioxide. Some potencies, such as As2O3 40x, 42x and 45x, have repeatedly shown a significant stimulating effect on germination compared to controls, whereas As2O3 35x has a significant inhibiting effect. In some experiments the seeds were stressed before the experiment with a sublethal dose of the same substance. We performed a statistical analysis, both for stressed and non-stressed seed groups, using Poisson distribution as a suitable model for representing the number of non-germinated seeds in a standard experiment with 33 seeds in the same Petri dish. Finally, we have considered the most repeated potencies (30x and 45x), computing the sample odds ratio (OR) and a 95% confidence interval (CI) for the population OR. Our results show significant reproducible effects of some As2O3 decimal potencies, particularly As2O3 45x. In stressed seeds, even decimal potencies of water seem to give significant results compared to control, whereas high dilutions of As2O3 without potentization never show significant effects.