A stream on the outskirts of Buenos Aires, Argentina, has turned a vivid crimson red, possibly due to industrial chemical dumping, according to images shared by residents on Friday.
The Sarandí stream, located near Villa Inflamable in the Avellaneda municipality, about six miles (9.6 km) south of Buenos Aires, runs through an area with numerous tanneries and industries that use chemicals to treat animal skins for leather production. Photos of the unnerving, blood-red water quickly spread across social media, with many comparing the scene to something out of an apocalypse.
Local newspaper La Verdad reported that residents detected a “nauseating” odor coming from the stream and suspect a nearby tannery could be the source.
“At 5:30 am, we already had a waste incinerator spewing pollutants into the air,” local resident María Ducomls told the Associated Press. “Shortly after, I saw the stream—it looks like a stream of blood. We have never seen it like this.”
Officials suspect the presence of aniline, a toxic chemical used in dyes and pharmaceuticals, as the cause of the discoloration. Water samples have been collected, and a formal complaint has been lodged with the Buenos Aires provincial ministry of infrastructure and public services, which will oversee the investigation.
Residents say the stream has changed colors multiple times in the past—gray, green, violet, blue, and brown—often with an oily sheen on the surface. Complaints against local industries date back to the 1990s, with several cases of environmental contamination still unresolved.
“On the morning of Thursday, 6 February, we received a report that the waters of the Sarandí canal had been dyed red,” the regional environment department stated.
A mobile analysis laboratory was dispatched to the site, where officials collected two liters of water samples for basic chemical analysis and liquid chromatography to determine the organic substance responsible for the discoloration. Authorities suspect it to be some form of organic dye.
By late Thursday afternoon, an AFP journalist reported that the water’s red hue had already begun to fade.
