In a sign that China still does not have a handle on quality control in a number of its industries, authorities have recalled drugs used to treat leukemia. Although it is not clear whether these have been exported, they have caused leg weakness and urine retention in patients within the large Asian country.

The compounds are put into a number of cancer drugs, so any distribution of them to manufacturers around the world could potentially do harm to patients with a number of diseases.

The first compound is methotrexate, which is used to treat a variety of cancers, arthritis, inflammatory bowel disease, psoriasis, ectopic pregnancies, and early pregnancy tissue that becomes malignant. The second drug is cytarabin hydrochloride, which is used for variety of cancers including leukemia, lymphoma, and Hodgkin's.

The two drugs in question where tainted with vincristine sulfate, which is used to treat HIV-related cancers and brain cancers, among other things. It has along list of severe reactions including seizures, loss of reflexes in the legs, and death. The side effects appeared recently in patients in China.

Given the lack of transparency in the highly competitive worldwide generic drug production, distribution, and sales industries, Americans have no assurance that these important medicines are contamination free. The pharma companies in the U.S. will almost certainly be faced with the kind of inspection issues that have hit big toy firms. That can be very expensive and can go a long way to undermine product confidence.

Douglas A.McIntyre is a partner at 24/7 Wall St.