-LRB- CNN -RRB- -- U.S. health officials said Wednesday they have found a contaminant in a blood-thinning drug produced by Baxter Healthcare Corp. that has been linked to more than a dozen deaths in the United States . The drug can keep potentially life-threatening blood clots from forming in the veins , arteries , and lungs . In early February , the Food and Drug Administration launched an investigation and then a recall of some forms of the product . The scrutiny began after a spike in reports of health problems associated with heparin , a drug made by Baxter from pig intestines at plants in China and Wisconsin . Though the cause of the problems has not been determined , FDA investigators found `` a heparin-like compound -- that is not heparin -- present in some of the active pharmaceutical ingredients '' in both facilities , said Dr. Janet Woodcock , acting director of the FDA 's Center for Drug Evaluation and Research . The contaminant , which made up 5 percent to 20 percent of each sample tested , `` reacts like heparin in some of the conventional tests used for heparin , '' which explains why it was not picked up , she told reporters in a conference call . No causal link between the contaminant and the adverse events has been established yet , Woodcock said . She added that it was not clear whether the contaminant was added accidentally , as part of the processing or deliberately . It also was not clear whether the contaminant was introduced in the company 's plant in Wisconsin or the one in China , Woodcock said . Though she said the exact structure of the contaminant has not been identified , `` it is similar to heparin glycans . '' Glycans are polysaccharides , a complex class of carbohydrate . She added it was unclear whether other heparin products used outside the United States might also contain the product . Later this week , the agency will release recommendations on how manufacturers and regulators can screen for the contaminant , she said . Last year , pet food made in China was found to be tainted with an ingredient that replaced more expensive protein and that initial tests did not identify as a contaminant . Asked if the heparin contamination could be a similar case , Woodcock said , `` It 's possible . '' Doctors have used the blood-thinner for 60 years with `` no history of any problems whatsoever , '' said the FDA commissioner , Dr. Andrew C. von Eschenbach . Its intravenous use can keep potentially life-threatening blood clots from forming in the veins , arteries and lungs . Von Eschenbach said it would be `` disingenuous '' to expect the agency would be able to inspect `` every institution in every case . '' Over the last fiscal year , the agency reported having inspected more than 1,000 foreign plants , a record . Since the agency issued its report that 19 deaths had been linked to the drug since January 1 , 2007 , it has received word of another 27 deaths , `` but many of those do not fit our definition of this type of event , '' Woodcock said . In all , the FDA has received 785 heparin-linked reports of adverse events -- including difficulty breathing , nausea , vomiting , excessive sweating and plummeting blood pressure that can lead to life-threatening shock . `` They 're continuing to come in fairly rapidly because there has been a lot of reporting of this , '' she said . In a written statement , Baxter said its tests have suggested `` that the root cause may be associated with the crude heparin , sourced from China , or from the subsequent processing of that product before it reaches Baxter . '' Meanwhile , Scientific Protein Laboratories LLC , which supplies the company with the active pharmaceutical ingredients , issued a statement saying it is working with the FDA , Baxter and outside experts to identify the cause of the adverse events . `` Thus far , no conclusions have been reached about the root cause , '' it said . `` It is premature to conclude that the heparin active pharmaceutical ingredient sourced from China and provided by SPL to Baxter is responsible for these adverse events . '' It said that its voluntary recall of suspect product was being made as a precaution . E-mail to a friend