Vegetable wholesalers in Shandong have been caught spraying toxic formalin on bak choi to keep them fresh in the latest food safety scandal to hit the mainland.

Vendors in Qingzhou said that spraying diluted formalin on bak choi had become a common practice locally in the past three to four years, the Xiaoxiang Morning Post reports.

A police officer in the town of Dongxia said yesterday that they had recently caught a vendor from Heilongjiang spraying formalin on a truckload of bak choi before embarking on a 10-hour trip to Langfang , Hebei .

“He was packing the bak choi into a truck on the side of the road and attracted our attention because of the strong smell of formalin, which he was trying to dilute with water,” the police officer said.

“The man said he had sprayed the formalin on the bak choi because the weather is hot now…