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bioaccumulation

This tag is associated with 16 posts
Svalbard Archipelago, Norway --- Polar Bear Mother and Cubs on Sea Ice --- Image by © Jenny E. Ross/Corbis

What’s in the Hair of a Polar Bear?

The accumulation of toxic methylmercury is a serious threat to wildlife all over the world – especially top predators in polar regions, like polar bears. Young polar bears are often the most vulnerable to detrimental effects of pollutants. To learn more about levels of mercury in polar bear cubs and their mothers, scientists measured total mercury content in samples of hair from bears in Western Hudson Bay.

Pretty, isn't it? "The Blue Marble" photograph of Earth, taken when the Apollo 17 mission travelled to the moon in 1972. This picture is featured on the official Earth Day Flag. [Wikimedia]

Go Green for Earth Day!

Do Mother Nature a solid with these helpful tips & tricks to go green today!

Juvenile Chinook salmon were monitored in this study. While adult salmon are known to travel far into the open ocean, these salmon were young enough that they had not yet traveled far from their spawning grounds, meaning that chemicals found inside the fish were likely from local sources. (Source: Wikimedia Commons).

Spawning Under the Influence: Drugs and Toxins Found in Salmon

You may think you’re familiar with the side effects of most common medications, but there are other, hidden side effects occurring beneath the surfaces of our oceans, lakes, and rivers. In this study, researchers brought these side effects to light by measuring a wide range of pharmaceuticals, drugs, and other manmade chemicals, in fish from Puget Sound.

Figure 2: Concentrations of toxic pollutants per gram of dried phytoplankton at each sampling location. Higher bars indicate greater total concentrations of POPs in plankton.

Tiny ocean creatures play a big role in the global fate of toxic pollutants

Scientists on the “biggest ever expedition on global change” studied the tiniest creatures in the ocean to learn about their role in accumulating and distributing toxic pollutants in the world’s oceans.

The slimy hagfish: not your typical fish. (Source: phys.org/news/)

The Secret’s in the Slime

Scientists have recently discovered that the hagfish’s notorious slime has uses beyond defense: it also mediates uptake of toxins through the hagfish’s skin.

We Don’t Know the Half of It: Hundreds of Contaminants in Dolphin Blubber from Southern California

Dolphins and humans are continuously exposed to low levels of various halogenated, persistent manmade pollutants through their diets. In this study, blubber samples from 8 dolphins were analyzed by cutting-edge techniques to find out what’s accumulating in these marine predators. Findings suggest many routine monitoring programs underestimate the exposure of marine mammals to toxins.

Smooth dogfish (Mustelus canis) is a common shark species along the US eastern seaboard, long considered a “trash fish” because of its high abundance and low commercial value (Source: Wikipedia.org)

Cartilaginous Conundrum: Are Sharks and Skates Safe to Eat?

While smooth dogfish may not be on your list of favorite seafood, cartilaginous fish (mainly sharks and skates) may increasingly find their way onto your dinner plate due to the decline of more traditional fisheries. While increased demand for these species as a food item could help struggling seafood industries, recent proposals to use dogfish in federal food programs beg the question: Is it safe to eat shark?

chileanseabass

Impostor! How mislabeled seafood affects the amount of mercury you ingest

Seafood mislabeling is a big problem for both consumers and fisheries management. Using genetic data and mercury concentrations, scientists figured out how frequently store-bought Chilean sea bass was swapped. Results indicate seafood substitutions can mean very different concentrations of mercury in your meal.

Photo Courtesy of www.aqua.org Copyright: Eric Baccega

The Hairy Truth: Using Grizzly Bear hair to study mercury levels

A large portion of the North American Grizzly Bear population call Western Canada home. The diet of these bears ranges from berries to mammals, and every year in the fall, coastal bears consume copious amount of Pacific salmon. This study investigates hair samples from Grizzly Bears and how they can be used to reflect dietary changes in mercury consumption.

Source: Keller et al.

Why Do Sea Turtles Get Tumors?

Large numbers of green sea turtles are growing tumors that impede their swimming, block their sight, and prevent them from feeding. Researchers know that the tumor-causing disease, fibropapillomatosis, is more prevalent in some areas than others, but no one knows why. In this study, scientists set out to determine whether exposure to chemical pollutants may make sea turtles more susceptible to fibropapillomatosis.

The adorable study subject (photo from Wikipedia)

Baby Beluga is at Heightened Risk: Pollutant Accumulation in Arctic Predators Affects Gene Expression

Analyzing changes in gene transcription is a way to detect adverse effects in organisms before they are observable on the whole organism level. Here, a Canadian research group set out to determine whether beluga whales in the relatively pristine Beaufort Sea are accumulating toxic pollutants at levels that could affect the future health of the beluga population.

StingrayCAM

Like Mother, Like Son: Stingrays Pass Toxic Pollutants on to Their Offspring

Animals in early stages of development are particularly susceptible to harmful effects of toxic pollutants. For this reason, the transfer of toxic pollutants from mothers to their young has been the subject of intense research. In this study, researchers from California State investigated how non-mammalian species like sharks, skates, and rays pass toxic pollutants on to their young.

Hebert_HgBirds_oceanbites2

Is the Oil Sands Industry in Canada Linked to Mercury Levels in Birds?

The oil or “tar” sands in Alberta, Canada are the third largest known reserves of accessible oil in the world. They are located around 200 km upstream of the Peace-Athabasca Delta, which is considered a wetland of international significance. This Delta is an ecologically sensitive habitat that provides services for millions of birds, which led a group of scientists in Canada to study mercury levels in bird eggs and investigate sources of mercury to the area.

Gavia immer is the scientific name for the common loon, a top predator and a prominent symbol of the northern wilderness. Picture by Bob Weaver.

Top predators reveal the extent of mercury pollution in Canadian waters

Common loons, walleye, northern pike, and yellow perch play integral roles in ecosystem dynamics and environmental policy decisions. In this research project, they act as useful indicators to determine dangerously toxic levels of methylmercury in Canada.

European Otter (Lutra lutra) and trends of some perfluorinated compounds (PFCs).

Disconcerting trends of pollutants in the Scandinavian Otter Population

Fluorinated compounds are an emerging class of persistent pollutants that have a global presence in the environment, biota, and humans, but are only now beginning to be regulated. A group of researchers from Scandinavia looked at liver samples taken from otters in Sweden and Norway from 1972-2011 and found that concentrations of many of these compounds have increased at disquieting rates, particularly within the last decade.

Bengston Nash 2013 Top Figure

Intense Weight Loss by Migratory Humpback Whales Could Increase Health Risks Posed by Pollutants

Australian and Norwegian researchers measured levels of pesticides and PCBs in southern hemisphere humpback whales to find out whether extreme weight loss during migration could have unforeseen consequences for the species.

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