[4] According to The New York Times, "problems with heparin reported to the agency include difficulty breathing, nausea, vomiting, excessive sweating and rapidly falling blood pressure that in some cases led to life-threatening shock.
[5][6][1] Upon investigation of these adverse events by the FDA, academic institutions, and the involved pharmaceutical companies, the contaminant was identified as an "over-sulfated" derivative of chondroitin sulfate, a closely related substance obtained from mammal or fish cartilage and often used as a treatment for arthritis.
[8] The raw heparin batches were found to have been cut from 2–60% with chondroitin and motivation for the adulteration was attributed to a combination of cost savings and a shortage of suitable pigs in mainland China.
The FDA has stated that it does not have the funds nor bear the responsibility to inspect on a regular basis overseas upstream processors of finished active pharmaceutical ingredients such as heparin.
However, according to the internationally harmonized guideline, ICH Q7, API manufacturers are fully responsible for qualifying their suppliers through on-site audits, testing, and regular communications.