US regulators have seized 11 lots of contaminated blood-thinner heparin from Celsus Laboratories in Cincinnati, Ohio.

The products were manufactured from material imported from China, and have been found by the US Food and Drug Administration to be contaminated with over-sulphated chondroitin sulphate, a substance derived from animal cartilage that mimics heparin’s anticoagulant activity.

The same substance was found in contaminated batches of Baxter’s heparin products earlier this year, which the company voluntarily withdrew from the market in February. The contaminated drug has been linked to more than 80 deaths in the US and hundred of allergic reactions.

The Celsus heparin had entered the USA prior to the FDA establishing import controls on the drug earlier this year following the initial reports of contamination. It was to be distributed to manufacturers in the US and abroad.

The seized heparin had been tested for the contaminant as part of the FDA’s effort to crackdown on the faulty drug. Celsus Laboratories had already been informed twice, in April and again in May, that that company’s actions to notify customers about a contaminant in its heparin were insufficient to assure an effective recall.

“This action will help prevent this contaminated heparin fro finding its way into the marketplace,” said Mike Chappell, The FDA’s acting associate commissioner for regulatory affairs.

To date, the FDA has initiated 13 recalls of multiple contaminated medical products containing heparin from several companies.