Magnesium sulphate: natural epsomite vs Epsom salt in lab tests
What it found
In lab tests on human cells, natural fibrous epsomite was more toxic than synthetic Epsom salt, which had negligible effects.
The difference appeared to come from impurities in the natural mineral.
What they found
Animal and lab studies
Toxicity comparison
Natural epsomite was significantly more toxic than Epsom salt in the lab tests. The effects of Epsom salt were considered negligible.
Oxidative stress and DNA
Natural epsomite caused more oxidative stress and DNA damage in the human cells than Epsom salt.
Inflammation
Natural epsomite triggered more inflammation in the lab-grown human cells than Epsom salt.
Role of impurities
The higher toxicity of natural epsomite came from toxic elements in its impurities, which were absent from pure Epsom salt.
What the authors conclude
“Generally, MP showed significantly higher toxicity in terms of oxidative stress, DNA damage and inflammation than SE, whose effects can be considered negligible.”
Also in their conclusions
- They say this research clarifies the role of impurities in the toxicity of natural epsomite, which may be higher than previously supposed.
- They state that, given its extensive use in the food industry, this represents a new step in assessing the safety of ingesting magnesium sulphate.
How it was done
Natural epsomite can be fibrous and inhalable, and Epsom salt is a common food additive that people can be exposed to daily, but its health effects are still debated.
They tested natural epsomite and Epsom salt on human colon cancer cells, colon cell layers, a human monocytic cell line and macrophages grown in the lab. They also identified and measured the impurities in the natural epsomite.
What it can’t tell you
- We summarised it from the abstract only.
- These were lab tests on human cells, not studies in people. They can't show what happens when magnesium sulphate is eaten.
- The tests used specific cell types grown in the lab, so the results may not reflect what happens in the whole body.
Who paid
- Conflicts
- Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
- Authors work at
- University of Urbino Carlo Bo, Italy; University of Genova, Italy; Inter-University Centre for the Promotion of the 3Rs Principles in Teaching & Research, Italy
The paper
- Title
- The cytotoxic/genotoxic role of impurities in soluble minerals: The case of natural (fibrous epsomite) versus synthetic (Epsom salt) magnesium sulphate
- Type
- Study
- Evidence
- Animals and lab studies
- Summarised from
- Abstract only
- Cite
- Giordani M, Mirata S, Scarfi S, et al (2025). The cytotoxic/genotoxic role of impurities in soluble minerals: The case of natural (fibrous epsomite) versus synthetic (Epsom salt) magnesium sulphate. The Science of the total environment. doi:10.1016/j.scitotenv.2025.178666PubMed 39904208DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error