Mysterious white particles that washed up onto a small section of southeast Spain's Valencian coast prompted authorities to close a handful of beaches on Monday as a precaution.
The local administration in Guardamar de la Safor, in the Gandia district of southern Valencia, said in a social media post that at least four area beaches would remain closed due to a "possible marine spill affecting our area, with an unknown material present in the sand."
The administration initially urged people not to swim until the material was identified and any risks it presents have been determined, but in a subsequent post it said the beaches would be closed.
An image posted on social media on June 8, 2025, by the local administration in Guardamar de la Safor, in southern Valencia, Spain, shows an unknown white material littering a local beach.
Ajuntament de Guardamar de la Safor/Facebook
The local government said it was in regular contact with the relevant authorities to follow up on sample testing and to ensure public safety.
Photos posted by the local authority showed long, undulating lines of small white particles, seemingly washed ashore by the tide, that appeared to be roughly the size of grains of rice.
They appeared similar in size to the small pellets of plastics that are shipped around the world as the raw materials to manufacture countless household and industrial products, but Spanish authorities did not immediately give any indication as to what they believed the material might be.
Local news outlet Valencia Plaza cited sources with the Valencian Port Authority as saying the most significant concentration of the contaminant appeared to be around the mouth of the Serpis River, which flows into the Mediterranean at Gandia, just north of the affected beaches. According to the sources cited by the outlet, that indicated a possible inland origin of the material.
An image posted on social media on June 8, 2025, by the local administration in Guardamar de la Safor, in southern Valencia, Spain, shows an unknown white material littering a local beach.
Ajuntament de Guardamar de la Safor/Facebook
At least four local beaches down the coast from Gandia were closed on Monday, Daimús, Guardamar de la Safor, Bellreguard and Miramar.
The affected area is more than 250 miles south of the bustling city of Barcelona, but it sits just north of some of Valencia's most popular tourist beach destinations on the picturesque Costa Blanca.
Valencia Plaza reported that environmental samples, both of water and the unknown substance, had been collected for analysis from various points along the affected coastline.
Tucker Reals