Doctor says initial PCB test results inconclusive

The chief of the medical team involved in the Tanapag health evaluation in connection with polychlorinated biphenyl (PCB) contamination in the village warned against making any conclusion that PCB level among residents are generally low and safe.

Dr. Richard Brostrom said the medical team has yet to receive majority of the results of the blood testings as he emphasized that laboratory testing for PCB is very complicated and difficult.

“Announcing that results are safe discourages residents from seeking medical follow-up,” he said. Since many residents have been found to have diabetes, hypertension and other illnesses, Dr. Brostrom said these issues must be discussed in private with their physician before results are announced to the public.

Acting Public Health Secretary Ned Arriola has announced a week ago that initial results on PCB tests showed PCB levels are very low, a statement that has drew angry protests from Tanapag residents.

The blood samples for PCB testing are being analyzed by California-based Smith Kline laboratory with the assistance of the National Medical Services Inc. in Pennsylvania. An average of 25 to 30 results arrive everyday on the island.

Some 1,200 residents have already availed of the free medical evaluation and PCB testing conducted by the Department of Public Health, which was carried out after strong pressure from Tanapag residents who have been exposed to the toxic chemical for more than 20 years.

Dr. Brostrom said the clinic has only received 200 to 300 results so far out of the 1,200 people who got tested. He added that some of the findings suggested high PCB levels among th residents, but he declined to elaborate.
The rest of the results are expected to come in July.

He however, emphasized the importance of sending some of the samples out to another laboratory for independent analysis and comparison. “We should not release our results until verification has been performed and the results are authenticated,” he added.

According to Dr. Brostrom, the medical team has yet to perform “lipid correction” which will allow them to compare PCB values between different population. PCBs travel with lipids (cholesterol and other fats) in the bloodstream. If two people have the same amount of PCBs in their bodies, the person with a high cholesterol will measure higher
PCBs on the serum lab test.

“We must perform ‘lipid correction’ to compare our results amongst the community and to other communities,” he said. But such technique cannot be conducted until all the results are placed in the computer.

Dr. Brostrom has also sought the assistance of the Agency for Toxic Substances and Disease Registry to fund the congener-specific testing that needs to be done on some of the residents who would have high levels of PCB. As each type of PCB chemical is called a “congener”, different PCB congeners have very different toxicity in animal studies.

Federal funding is needed since measuring PCB congener in blood is very expensive. “We don’t know yet which PCB congeners are inside the blood of the residents and I want it done as soon as possible,” he said. Congener testing will cost approximately $200 for each person.