It’s hard to know where it began. But one of the first recorded cases was in Cornwall, England, on the dog-friendly beach of Long Rock near the Strait of Dover. Coincidentally, this is also the busiest shipping lane in the world. It was October 2013 and the black-haired mini-schnauzer, Zanzi, was out for a walk with his owners. He had meandered away and soon, he was munching on something, owner Lucy Garrett-Peel told the local Cornishman paper days later. His snack was white and waxy and “all over the beach,” said Peel, who raced over to grab it that day. “It was really unpleasant and the smell was like nothing I have ever come across,” she said. It smelled a bit like diesel.