# Natura mineral water safety investigation > Developing situation record from CLSTR: https://clstr.news/situations/natura-mineral-water-safety-investigation > Updated: 2026-10-10T07:41:12.000Z. Sources: 12. Developments: 2. In September 2026, the Public Health Authority of the Slovak Republic issued an urgent warning regarding Natura lightly sparkling mineral water in 500 ml bottles. Laboratory testing indicated an extremely high pH level of 14, suggesting the presence of a highly alkaline, corrosive substance that could cause chemical burns, vomiting, or internal bleeding. The alert specifically targeted batch L61481/00:20, which was bottled in the Czech Republic and distributed by Coca-Cola Czech Republic. By October 2026, the State Veterinary and Food Administration of the Slovak Republic conducted tests that confirmed the specific batch met legislative requirements and did not contain corrosive substances. This investigation followed a report of a minor experiencing health difficulties after consuming the water. While the tested batch was found to be safe, criminal proceedings remain ongoing to determine if contamination occurred during production, distribution, storage, or sale. ## Timeline ### 2026-10-10: Natura mineral water batch cleared of corrosive substance in tests Tests by Slovak food authorities confirmed a batch of Natura mineral water is safe, following an investigation into a bottle that showed high pH levels indicating a potential corrosive substance. 3 sources. https://clstr.news/cluster/natura-mineral-water-batch-cleared-of-corrosive-substance-in-tests ### 2026-09-15: Natura mineral water recalled due to dangerous pH 14 levels Slovak health authorities warn against consuming Natura lightly sparkling mineral water (500ml, batch L61481/00:20) after tests showed a dangerous pH level of 14, which can cause chemical burns. 9 sources. https://clstr.news/cluster/natura-mineral-water-recalled-due-to-dangerous-ph-14-levels --- Cite as: Natura mineral water safety investigation. CLSTR, https://clstr.news/situations/natura-mineral-water-safety-investigation