THE city’s food safety watchdog recently ordered 13 batches of fish and seafood products to be withdrawn from sale after they failed to pass routine quality checks.

Most of the substandard goods were found to contain “unsafe” levels of banned substances, such as antibiotics, malachite green dye, sulfur dioxide and other additives, the Shanghai Food and Drug Administration said yesterday.

The announcement was made following checks on 169 batches of foodstuffs, the majority of which returned positive results, it said.