Nobody knew what they were at first.

They've been described as “strange spongelike clumps,” “yellow mousse” and, perhaps most disturbingly, “possibly the biggest balls of earwax ever.”

In recent weeks, hundreds of thousands of mysterious yellow blobs have swept across about 20 miles of the beaches in northern France, according to the Local. Ranging in size and shape, the balls looked like they had the consistency of anything from packing foam to unbaked scone dough.

The unexplained arrival of the spongelike balls baffled locals and tourists alike along France's Opal Coast, usually better known for its tranquil beaches and laid-back fishing villages.

It wasn't long before speculation and tongue-in-cheek headlines about the shapes emerged. Many jokingly pointed to a certain pineapple-dwelling underwater character.

Last week, local firefighters collected samples and sent them to be analyzed. The spongelike clumps were deemed to be paraffin wax, and Pas-de-Calais prefecture officials said in a statement that the substance did not pose any danger to public health or flora and fauna, according to La Voix du Nord.

The statement also noted that the paraffin wax did not need to be specially treated before being discarded — but did warn visitors with children not to accidentally eat any.

In an interview with Canadian Broadcasting Corp. Radio, however, Jonathan Hénichart, president of the nonprofit Sea-Mer Association, said he still had concerns about what the beached sponge balls could mean. He suspects that a cargo ship carrying industrial paraffin wax may have washed its tank and emptied the paraffin residue too close to shore. It wasn't the first time paraffin wax had appeared on France's shores, he added.

“The first time it was not yellow, it was a pink paraffin wax, and then this winter, we got three tons of this paraffin wax but it was white,” Henichart told “As It Happens” host Helen Mann. “And now we received some yellow ones. I don't know maybe they think it's funny to send us some different colors each time.”

Henichart added that even though local officials had said the substance was harmless, the sheer amount of wax on the beach “makes it toxic because the local wildlife will live with this.”

“It looks like regulations are too light,” Henichart told CBC Radio. “It’s too easy for ships are able to do what they want.”

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