Health authorities in Taipei found benzopyrene above the standard in four sesame oil products, including black sesame oil and a premium grade, following expanded testing of items on sale.

Benzopyrene can form when oils are roasted or pressed at high temperature. Temperature control has long been identified as the crux in traditional methods that roast sesame seeds hard.

The authorities ordered the products removed from shelves as a precaution, with tracing of distribution routes and inspection of manufacturers proceeding alongside.

Sesame oil is a staple seasoning in Korean, Chinese and Taiwanese households alike. Because small amounts are used over long periods, affected bottles may remain in homes.

Consumers are advised to check batch numbers and use-by dates on labels, with return procedures handled through the point of purchase.

Taipei has been widening the scope of food testing, with dried goods and seasonings generally included alongside oils.