Grand Canal, a channel in Venice, Italy, is popular among tourists and locals. However, it turned bizarre in the past few days after some water turned bright green.

What Happened to Venice's Grand Canal?

On Sunday, sections of the canal, notably those close to the Rialto Bridge, were discovered to have changed color to an alarming shade of green.

The Veneto regional president, Luca Zaia, confirmed that some locals near the Rialto Bridge reported seeing a patch of phosphorescent green liquid in the Grand Canal of Venice. To look into the source of the liquid, the prefect has summoned an urgent conference with the police, CNN reported.

Before calling an emergency meeting to investigate the cause of the green water, the local prefect spokesperson told CNN that they immediately took water samples, looked over CCTV surveillance tape, and asked local gondolier pilots and boat drivers if they saw anything suspicious. They also noted that no environmental organization had claimed responsibility.

Someone observed the lush glob around 9:30 a.m. CET (3.30 aET). Several pictures shared on social media showed gondolas, water taxis, and water bus boats skimming through the emerald substance, and they noticed that it grew steadily.

Andrea Pegoraro, a city councilman, instantly laid the responsibility for the recent attacks on Italian cultural heritage sites on environmental activists.

When questioned if they were responsible for the green water in the Trevi Fountain in Rome last weekend, the collective Ultima Generazione responded, "It wasn't us."

According to AFP, the Regional Agency for Environmental Prevention and Protection of Veneto (ARPAV) determined that fluorescein, a non-toxic chemical used to monitor wastewater networks, was the actual cause of the green glow. The dye's source has remained unclear, Newsweek reported.

Zaia also shared a photo of the brilliant green patch of water that surfaced in the waterways of Venice yesterday morning and said there was no contamination threat.

The first studies were performed in the late morning by ARPAV technicians using colored water. The green liquid is an organic coloring substance used in caving or for water checks.

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What Is Fluorescein?

Fluorescein is a powdered synthetic dye that has a dark orange-red appearance. When dispersed in a liquid, its hue is influenced by the pH, illuminating a distinctive bright green in alkaline conditions.

Several ocular procedures, such as checking for corneal or vascular abnormalities, use fluorescein as a diagnostic contrast agent. According to NIH, Fluorescein can also be used to bioimage entire anatomical structures, and in immunohistological labeling, it can even be used to image individual cellular components.

Venice's canals have previously been colored with this substance. In 1968, Argentine artist Nicolas dyed the Grand Canal a similar shade of green as a protest against environmental degradation during the 34th Venice Biennale.

The recent alteration of Venice's waters has raised questions about whether it is an environmental protest or, even if it isn't, whether it could inspire future actions comparable to the one in 1968.

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