In mid-December the Virginia Department of Health revised their guidelines for fish consumption advisories due to the contamination of fish with polychlorinated biphenyls (PCBs).
"There is absolutely no increase in PCB levels," said Trina Lee, spokeswoman for the state health department. "The change is in the protection levels, it's our advisories that have changed."
Chemical contaminants classified by the U.S. Environmental Protection Agency, PCBs are probable human carcinogens.
According to the health department, long-term exposure to PCBs may increase the risk of cancer.
The health department also reports "some studies in humans have also suggested that PCB exposure may cause adverse developmental effects in children and developing fetuses. Infants and children are particularly sensitive to the effects of PCBs because their nervous systems are still developing. PCBs also build up in women’s bodies and are often passed on in the mother’s milk. Therefore, VDH is recommending that high risk individuals, such as pregnant women, woman planning to become pregnant, nursing mothers, infants, and young children should avoid eating PCB-contaminated fish from the advisory areas."
Although there are no known current sources of PCBs in water, past uses in hydraulic fluids, plasticizers, adhesives, fire retardants, pesticide extenders, dedusting agents, inks, cutting oils, heat transfer systems, carbonless reproducing paper and leaking transformers have contributed to the environmental contamination.
Because there are so many bodies of water or streams where fishermen may catch fish the health department has not issued warnings on one species of fish over the other.
For the Chesapeake Bay area — mainstream and its small coastal tributaries, the state warns that Anadromous (Coastal) Striped Bass should be consumed no more than twice a month.
Other coastal areas, fish and consumption regulations can be found on the department's web site at http://www.vdh.virginia.gov/HHControl/fishingadvisories.asp.
Lee explained because other states — Maryland and North Carolina — recently changed their fish consumption advisories, Virginia did the same.
Eleven of the original advisories were modified and 27 new advisories were issued as a result of the changes.
These new advisories are more protective of human consumption due to information that suggests a person may consume fish from the same waters for more than 30 years.
Originally research suggested that individuals only consumed fish from the same source for nine to 12 years.
Because PCB levels are calculated based on how many years an individual consumes fish from one specific source, the health department decided to change the guidelines in light of this most recent information.
The health department's guidelines divide PCB levels into three groups:
• fish with less than 50 parts per billion (ppb) have no restriction on consumption.
• fish with 50-500 ppb are limited to no more than two meals per month.
• fish with more than 500 ppb should not be consumed.
Women who are pregnant or may become pregnant, nursing mothers and young children should not eat any fish from the advisories.
Maryland and North Carolina made similar changes in recent years and because Virginia shares water bodies with both states, the new guidelines provide more consistent advice to regional fishers.
Historically the state has lowered the levels of PCBs considered acceptable in fish. Before 1980 the health department followed guidelines developed by the U.S. Food and Drug Administration (FDA) that considered PCB levels higher than 5,000 ppb exceeded safety levels.
Four years later the FDA reduced the level to 2,000 ppb and in 1998 the state health department developed its own fish consumption advisory guidelines set its level of concern for PCB consumption to no more than 600 ppb.