To ease public concern over contaminated capsules, the nation's top drug authority has ordered pharmaceutical companies to beef up their quality control and testing procedures.

Starting on May 1, pharmaceutical firms are required to test every batch and category of capsules they purchase before producing drugs, according to an online notice issued by the State Food and Drug Administration over the weekend.

Local drug watchdogs must verify the test results released by these companies to ensure authenticity, the administration said.

Capsule drugs that were manufactured or put on the market before that date should also be screened for potential chromium contamination, it said.

"The latest initiative shows the firm resolution of the drug watchdog to close the loophole in the implementation of regulations that led to the capsule safety crisis," Sun Zhongshi, an expert with the National Rational Drug Use Monitoring System under the Ministry of Health, told China Daily on Tuesday.

To date, products from 15 gel capsule producers have been found to contain excessive levels of chromium. The administration has imposed an immediate product recall and called for the destruction of the chromium-tainted products.

According to the Chinese Pharmacopoeia 2010, before production, drug manufacturers must test non-active substances - including capsules - used to make medicines. And it has set standards and specific testing methods for capsules.

However, in practice some drug companies failed to follow the rules strictly, making it possible for substandard cheap capsules, illegally made from industrial gelatin, to enter the link of drug production, Sun explained.

According to Chen Junshi, a food safety expert at the Chinese Academy of Engineering, edible gelatin is manufactured with animal bones and skins, and is widely used in food and drug industries.

However, some chemical companies made drug capsules using mainly discarded leather products, Sun noted.

The administration, to further strengthen regulation over capsule makers, ordered them to draft specific standards on raw materials, mainly animal skins, bone, and tendons, the notice said.

It also said that all producers of capsules have to be equipped with testing facilities and staffed with professional testing workers.

By Oct 1, production will be suspended at firms that fail to meet the requirements, according to the administration.

The Ministry of Health, in a recent statement, ordered medical institutions on the Chinese mainland to stop administering medicines found to have contaminated capsules and to help drug authorities recall them.

Hospitals have been asked to report to local health administrations whether they have these contaminated capsules and how many they still have in stock, the statement said.