One of Taiwan’s oldest food companies announced a recall last week of 12 products after finding out they may have been made with oil recycled from kitchen and industrial waste. Wei Chuan Foods has been pulling the products from the shelves of major retailers, including Carrefour, RT Mart, Far Eastern A-Mart and PxMart. Consumers are being told to return the recalled products for refunds. The company said that since April it had used about 15.6 tons of supposedly lard-based oils provided by Kaohsiung-based Chang Guann Company as ingredients for the products. Some of the oil was allegedly recycled from kitchen waste and possibly industrial uses and may also have been used to make lunch items for local schools. According to media reports, Taipei police arrested six people on Thursday in connection with the situation, and they also seized some of the tainted oil. The company’s stock reportedly took a hit last week after the news broke and was down to its lowest point since January 2013. The waste oil may also have been sold to more than 1,000 other companies to make as many as 139 different food products, including bakery items sold in Hong Kong. As a result, Chinese groceries were reportedly pulling Taiwanese brands off the shelf this past weekend. Wei Chuan has a U.S.-based subsidiary headquartered in California that manufactures and distributes mainly frozen and other food products such as dumplings, potstickers and egg rolls. In June, there was a recall involving its pork buns due to misbranding and undeclared allergens.