TOXIC SEALS: OUR POLLUTED WATERS
SENTINELS OF THE SOUND
Harbor seals are unfortunate and unwitting barometers for our polluted environment. An ecosystem poisoned by mankind with contaminants, sewage, trash and inorganic marine debris directly impacts their health and that of all living beings in and around the waters of Puget Sound, Elliott Bay and the Duwamish River.

DEADLY TOXINS ARE ABSORBED BY MARINE MAMMALS
Harbor seals in particular are affected by pollution because they do not migrate, but instead, live year-round in our region. Because of this, they are considered a sentinel species, indicating the health of the marine environment. If the seals are sick, our waters are sick.

Seals' thick layers of blubber absorb and retain pollutants from our industrial waterways. In fact, a 2005 study showed the harbor seals of South Puget Sound were 7 times more contaminated than those living in Canada’s Georgia Strait. Biologists use tissue samples from both live and dead seals to monitor the health of the Sound, measuring levels of PCBs, increasing numbers of chemicals used in flame retardants known as PBDEs, pesticides and other highly toxic waste.

While a ban of PCBs has reduced those toxins in recent years, the number of chemicals used in flame retardants (including those known as PBDEs) have greatly increased. Studies show that PBDE concentrations have been doubling every 3.5 years and have even been detected in the high Arctic.

Contaminants are stored in the blubber of marine mammals at the top of the food chain, such as dolphins, seals and orcas. The Southern Resident orcas are among the most contaminated marine mammals in the world. These toxins pass from generation to generation through the milk of mothers to their offspring. Humans, of course, are also at the top of the food chain - and those who consume fish from these toxic waters have high contaminant loads.

In the Main Basin of Puget Sound, seal pups are more highly contaminated with PCBs and PBDEs than other areas of Puget Sound. Sadly, because seal pups are so contaminated, they are considered the ideal subject for these studies.

Exposure to flame retardants causes physical abnormalities (including that of the brain, impairing the development of motor activities and cognition), behavioral changes, impairs reproduction and causes immune disorders in marine mammals.

In recent years, researchers discovered a link between contaminants and compromised immune systems of harbor seals. Weakened seals become vulnerable to parasitic infections, low body weight and numerous viruses, often leading to fatalities. Read the full study of contaminants in Puget Sound here.

Harbor seals and pups haul out on the wooden piers and beaches in the highly industrial and contaminated Duwamish Waterway, a superfund project. They forage for food in the same waters where signs warn that shellfish is unsafe for human consumption due to contaminants. A number of pups in this location were found by Washington Department of Fish and Wildlife and PAWS Wildlife Center, a NOAA resource for harbor seal rehabilitation, to have lungworm infestation, pneumonia and/or a fatal virus.

STORM RUNOFF POLLUTES THE MARINE ENVIRONMENT
Storm runoff has become a major factor in marine pollution. Chemicals added to lawns, gardens and agricultural fields, human and animal waste, highway oil and gasoline residue all can end up in our waterways. Household chemicals and pharmaceuticals flushed down a drain end up in our waters as well --- and ultimately into our fish, seals and other marine mammals.

Puget Sound now has areas where no marine life can subsist, known as dead zones. Learn more about how dead zones are growing globally. While climate change plays an important part, so does agricultural storm runoff which produces a toxic bloom of algae, which poisons marine life and is having an especially devastating effect on West Coast sea lions.

View the recent Frontline PBS documentary Poisoned Waters which features our troubled Puget Sound.

PLASTICS BREAK DOWN INTO MINUTE PARTICLES AND ENTER THE FOOD CHAIN
Plastic bags and balloons are often mistaken for food. If consumed by marine mammals, it can result in a slow and painful death. Plastic litter does not biodegrade; instead, it photo-degrades - a process where sunlight breaks it down into minute pieces of plastic that enter the food chain. These plastic polymers are a magnet for pcbs and other toxic chemicals. Once ingested they create hormonal imbalances and affect reproductive abilities and brain activity in fish, invertebrates and marine mammals.

Plastic litter from all over the earth ends up in the ocean, gets caught up in ocean currents and has created a giant swirling mass of 7 million tons of toxic debris twice the size of Texas - dubbed the "Great Pacific Garbage Patch." The waters in this immense area contain 6 times more plastic than plankton, a primary food source for fish and marine mammals. This garbage vortex is not the only one in the oceans, just the biggest.

Contaminant-laced plastic is found at all levels of the food chain in our oceans, ultimately affecting humans as well who consume seafood.