The case of the "mysterious poisoning" of a guest in a Rijeka café caused by drinking bottled mineral water has finally been solved after it was found that the 19-year-old man was poisoned by an alkaline liquid poured into an empty bottle and later misplaced among other bottles of mineral water.

Croatian police announced on Friday that they had filed charges against two 38 and 39-year-old owners of a catering business on the island of Krk. They are alleged to have poured an alkaline liquid, namely a cleaning agent, into an empty mineral water bottle. Later, the two suspects carelessly and negligently placed this bottle among other unopened bottles of mineral water, which were eventually returned to the beverage distributor who sold them to the café in Rijeka where the accident occurred on 4 November 2023.

After the 19-year-old was admitted to a hospital in Rijeka with severe damage to his oesophagus after consuming the drink in question, the health authorities took samples and sent them for analysis. The samples were analysed for pH, metals and metalloids, pesticides and additives.

The drink contained a cleaning or degreasing agent

Subsequently, the media reported suspected poisoning in several consumers after consuming some other drinks produced by the Coca Cola company.

The health authorities then sent a sample of Coca-Cola Original Flavour from a 500 ml bottle taken from a vending machine and two samples of Coca-Cola Original Flavour and Coca-Cola Zero from 2-litre bottles taken from a retail shop in Zagreb for analysis.

The Forensic Science Centre Ivan Vucetic in Zagreb found that the soft drink consumed by the 19-year-old man in Rijeka contained a cleaning or degreasing agent, the Ministry of the Interior announced in mid-November 2023.

The results of the forensic examination of the liquid from the glass from which the man had been drinking when he fell ill show that the physical and chemical properties of the analysed liquid matched the liquid from the soft drink bottle. The analysis also revealed that it was a highly alkaline solution (pH=13.6), the ministry said in a press release.

The chemical compounds identified in the liquid indicate that it is a cleaning or degreasing agent.

Twenty bottles of the same beverage in the original packaging were found to be safe for consumption and the pH values measured were within the standard range for this beverage.

Minister Beros: The case in Rijeka was an isolated incident

As for the case reported in Zagreb on 7 November, the bottle of the drink in question had the standard pH value for this soft drink and no unusual compounds were detected.

The State Inspectorate has received a test report from the Croatian Institute of Public Health on the samples of Coca-Cola drinks taken from a vending machine and a retail shop in Zagreb, and they were found to be safe.

In addition to the Coca-Cola drinks in question, a sample of Römerquelle Emotion from the restaurant in Rijeka where the man fell ill was also analysed and showed that to be safe.

After the results were announced, the Coca-Cola products that had been recalled from the shops and restaurants were returned to the shelves and restaurants.

On 9 November 2023, Health Minister Vili Beros said there was no need to panic and continue spreading fears about the harmful consumption of soft drinks, as the case in Rijeka was an isolated case, adding that it was not good to listen to fake news.