Mexico's navy said today that marines found the phenyl acetic acid in 720 drums aboard the cargo ship Coyhaique the previous day at the Pacific port of Manzanillo.
The ship had set out from Shanghai and was bound for Lazaro Cardenas, another port on the Pacific coast. Drug cartels have long imported such chemicals through Lazaro Cardenas.
Phenyl acetic acid is used to produce methamphetamine at clandestine labs, and the product is often exported to the United States.