Scientists unveiled some exciting news at the 2016 Salish Sea Ecosystem Conference in Vancouver, BC. Several species of wildlife in Puget Sound – harbor seals, Pacific herring, and English sole – show decreasing levels of toxic flame retardant PBDEs in their bodies. Continue reading 

Seattle – Scientists have been puzzling over why toxic flame retardant chemicals used in products in our homes, like couches and TVs, are showing up in Puget Sound, rivers, and other waters across the state.

Now they have an answer thanks to a new peer-reviewed study published today in the journal Environmental Science & Technology (pay required). Continue reading 

Editor’s Note: This is part two of a two-part series, A Non-Sticky Situation, that examines perfluorinated compounds or “Teflon chemicals,” in Puget Sound. Part one looked at why the characteristics of Teflon chemicals make them problematic for the fish and wildlife of Puget Sound. It is part of a series of posts delving into some of the the chemical pollutants that have contaminated Puget Sound’s fish and wildlife and pose one of the greatest threats to their survival. Continue reading 

Editor’s Note: This is the fifth installment in a series of posts looking into some of the the chemical pollutants that have contaminated Puget Sound’s fish and wildlife and pose one of the greatest threats to their survival. This is part one of a two-part series that examines polychlorinated biphenyls (PCBs), which are still polluting people and the environment despite being banned over 30 years ago.

This post was written by Dr. Fran Solomon, an environmental biologist who teaches courses and gives seminars for university students, environmental and health care professionals, and the general public about toxic chemicals and how they affect human health and the aquatic environment.

When I served as an environmental scientist for the Washington Department of Ecology in the 1990s, one of my responsibilities was to inspect businesses and industries on the shores of Puget Sound for compliance with environmental regulations. Before embarking on this part of my job, I was required to undergo a thorough medical checkup including analysis of toxic chemicals in my blood. I was surprised to find out that low levels of polychlorinated biphenyls (PCBs) were present. The nonflammability, heat resistance, and insulating properties of these manufactured chemicals made them useful in the electrical and plastics industries from the late 1920s until the late 1970s (1). However, I had never worked in these industries. Furthermore, PCBs had been banned in the U.S. 12 years before my checkup.

So what were PCBs doing in my blood? They were present because they are persistent toxic chemicals. They hang around for a long time and accumulate in the tissues of organisms, especially the fatty tissues. Their ability to biomagnify in food chains means that each predator will accumulate higher levels of PCBs than were present in its prey. Top predators such as orca whales, other large marine mammals, birds of prey such as ospreys and bald eagles, and humans will have the highest levels of PCBs in their bodies (1,2).

My exposure was likely through the food chain, when I ate fish, meat, and dairy products contaminated with the chemicals. Just like my exposure through the food chain, Puget Sound’s wildlife is similarly exposed to PCBs in their food. Puget Sound resident orca whales have the highest PCBs levels of any whales on Earth. This is because they are at the top of the food chain and eat Chinook salmon that have accumulated PCBs from their prey (3).

Because they are so persistent, more than 30 years after bans in the U.S. and many other countries, PCBs continue to be found in soil, sediments, fish, wildlife, and most people including people living thousands of miles from the sources of these chemicals. Wind currents transport PCBs long distances, where they then settle out in lakes, streams, rivers, and oceans, and make their way up the food chain.  The Inuits, who inhabit northern Canada and Baffin Island, eat the meat and blubber of large marine mammals and have the highest PCBs levels of any people in the world (1,4).

PCBs in Puget Sound

For more than 20 years, the Washington Department of Fish and Wildlife (WDFW) has been sampling Puget Sound fish for the presence of PCBs and other toxic chemicals. Every two years, WDFW biologists sample 120 English sole at each of 10 locations in Puget Sound. PCBs have the ability to glom onto sediments, exposing the animals that live there. Because English sole feed in the sediments at the bottom of Puget Sound, PCBs levels in these fish reflect sediment levels of PCBs. The accumulation of PCBs in sediments and aquatic organisms means that these both can be considered reservoirs of  PCBs in Puget Sound.

Sadly, scientists are not finding consistent declines in these chemicals in our local fish. During a recent fish sampling and analysis day, WDFW biologist Jim West said “ levels of PCBs in English sole and other Puget Sound fish species have remained constant during the past 20 years for most locations, neither increasing nor decreasing” (2).  

Sediments that are contaminated can be cleaned up by removing the sediments or capping them with clean sediments. There have been successful sediment cleanup projects in Puget Sound. For example, PAHs, another class of contaminants, are now lower in the sediments of Sinclair Inlet adjacent to the Puget Sound Naval Shipyard and lower in Eagle Harbor on Bainbridge Island than they were 20 years ago.  This has resulted in a reduction of contaminant-related disease in English sole from Sinclair Inlet and Eagle Harbor (2,5).   

But cleanups are expensive. The most cost-effective approach to reduce exposure of fish and humans to toxic chemicals is to prevent discharge of such chemicals at the source. Unfortunately, it is too late to do this for PCBs. As Jim West pointed out, “The cat is already out of the bag on PCBs.  We need to apply lessons learned from PCBs contamination of sediments and fish to other toxic chemicals in Puget Sound” (2).

1.  Wright, David A. and Pamela Welbourn (2002).  Environmental Toxicology.  Cambridge University  Press, Cambridge, U.K.

2.  West, Jim, Washington Department of Fish and Wildlife, Interview, May 17, 2011

3.  Ross,, P.S., G.M. Ellis, M.G. Ikonomou, L.G. Barrett-Lennard, and R.F. Addison (2000).  “High PCB concentrations in free-ranging Pacific killer whales, Orcinus orca: effects of age, sex and dietary preference.  Marine Pollution Bulletin 40: 504-515.

4.  Colburn, Theo, Dianne Dumanoski, and John Peterson Myers (1997).  Our Stolen Future, Penguin Books, New York, N.Y.

5.  Myers, M.S., B.F. Anulacion, B.L. French, W.L. Reichert, C.A. Laetz, J.Bozitis, O.P. Olson, S. Sol, and T.K. Collier (2008).  “Improved flatfish health following remediation of a PAH_contaminated site in Eagle Harbor, Washington.” Aquatic Toxicology 88: 277-288.

Editor’s Note: This is the fifth installment in a series of posts looking into some of the the chemical pollutants that have contaminated Puget Sound’s fish and wildlife and pose one of the greatest threats to their survival. This is part two of a two-part series, The Chemicals That Just Won’t Go Away, that examines polychlorinated biphenyls (PCBs), which are still polluting people and the environment despite being banned over 30 years ago. 

This post was written by Dr. Fran Solomon, an environmental biologist who teaches courses and gives seminars for university students, environmental and health care professionals, and the general public about toxic chemicals and how they affect human health and the aquatic environment.

Lowered Resistance to Disease

At the same time that I found out there were PCBs in my blood, 18,000 harbor seals died in the North Sea. This was 40% of the harbor seal population in this body of water located between Great Britain and the Netherlands. Simultaneously, a viral infection that swept through the striped dolphin population in the Mediterranean Sea resulted in the deaths of 1,100 dolphins. In both situations, there was a correlation between levels of PCBs in the blood of the dead animals and weakened immune defense systems shown by lower white blood cell counts and antibody levels. Normally, the striped dolphins would have been able to fight off the infection in the same way that humans can fight off colds and other viral infections (1).  In Puget Sound, tests have found that some ospreys and orca whales have high enough levels of PCBs in their bodies to weaken their immune defense systems (2,3).
 
Impaired functioning of the immune defense system is seen in exposed humans too. Inuit infants, who have elevated levels of PCBs in umbilical cord blood at birth, suffer higher rates of ear infections and other respiratory diseases than other infants in the province of Quebec. Prenatal exposure to PCBs may have weakened the developing immune defense systems of the Inuit infants (4).

 Jim West explains how PCBs are still ending up in Puget Sound

Effects on Brain Development

In the 1980s, some 11-year old children in the Great Lakes region of North America did not perform well on tests of intelligence, short-term memory, verbal skills, and muscle coordination. The common factor among these children was that their mothers had eaten Great Lakes fish—contaminated with PCBs—two or three times each month before becoming pregnant. The PCBs had accumulated in the bodies of the women at higher levels than in the fish, and were then exported across the placenta to the developing fetuses. When the babies were born, they looked normal but it turned out their brains had been compromised, with the most severely affected 11-year olds born to mothers with the highest PCBs levels in their blood or milk. We now know that PCBs impair the functioning of the thyroid gland, which plays an important role prenatally in brain development (1,5).

Hormone Disruption

Pacific salmon were introduced into the Great Lakes of the U.S. and Canada in the 1960s. By the 1990s, many Great Lakes salmon had enlarged thyroid glands correlated with high levels of PCBs in their blood and muscle tissue. Enlarged thyroid glands indicate subnormal levels of thyroid hormones (1).
 
PCBs are structurally similar to the female sex hormone estradiol. Not surprisingly, they mimic this hormone and can trick the cells of an exposed organism into reacting in the same way as they would react to estradiol. A large body of evidence indicates that continual exposure to low levels of PCBs and other endocrine-disruptor chemicals has contributed to the threefold increase in the breast cancer rate of American women since 1960. A study of 224 Long Island, New York women with early stage breast cancer showed that women with the highest blood PCBs levels had the highest risk of recurrence (6).
 
People can reduce their exposure to PCBs by eating fish with low PCBs levels in the fillets and avoiding species such as sediment-dwelling bottom fish that have high PCBs levels.  The Washington State Department of Health website (www.doh.wa.gov) provides advice on which fish can be eaten frequently, which should be eaten only occasionally, and which should be avoided.
 
Unfortunately for orcas and other wildlife in Puget Sound, they haven’t learned to go to helpful websites and follow fish consumption advice. The cat may be out of the bag with PCBs, but it’s not too late to enact policies that will keep us from repeating history with long-lasting chemicals that harm both people and wildlife.
 
1. Colburn, Theo, Dianne Dumanoski, and John Peterson Myers (1997).  Our Stolen Future, Penguin Books, New York, N.Y.

2. West, Jim, Washington Department of Fish and Wildlife, Interview, May 17, 2011

3. Hickie, B.E., P.S.. Ross, R.W. MacDonald, and J.K.B. Ford (2007).  “Killer whales (Orcinus orca) face protracted health risks associated with lifetime exposure to PCBs.” Environmental Science and Technology 41(18): 6613-6619.

4. Dallaire, Frederic, Eric Dewailly, Carole Vezina, Gina Muckle, Jean-Philippe Weber, Suzanne Bruneau, and Pierre Ayotte (2006).  “Effect of prenatal exposure to polychlorinated biphenyls on incidence of acute respiratory infections in preschool Inuit children,” Environmental Health Perspectives 114: 1301-1425. 

5. Jacobson, J.L.and S.W. Jacobson (1996). « Intellectual impairment in children exposed to polychlorinated biphenyls in utero.”  New England Journal of Medicine 335: 783-789.

6. Gray, Janet, ed. (2008). State of the Evidence: What is the Connection Between the Environment and Breast Cancer?  5th edition, Breast Cancer Fund (http://www.breastcancerfund.org), San Francisco, CA.

Editor’s Note: This is the fourth installment in a series of posts looking into some of the the chemical pollutants that have contaminated Puget Sound’s fish and wildlife and pose one of the greatest threats to their survival. This is the second of two posts examining the effects of hormone-disrupting chemicals (including BPA) on the Sound. The first post can be found here Continue reading 

Editor’s Note: This is the third installment in a series of posts delving into some of the the chemical pollutants that have contaminated Puget Sound’s fish and wildlife and pose one of the greatest threats to their survival. This is part two of a two-part series that examines phthalate chemicals found in everything from vinyl shower curtains to shampoo.

This post was written by Dr. Fran Solomon, an environmental biologist who teaches courses and gives seminars for university students, environmental and health care professionals, and the general public about toxic chemicals and how they affect human health and the aquatic environment. Continue reading