Monthly Archives: January 2014

Mercury from Natural Sources May Contribute to Freshwater Fish Contamination

By Roberta Attanasio, IEAM Blog Editor

Moving in an endless cycle, mercury goes from the atmosphere to soil, water and sediment, and then back to the atmosphere. While moving around, mercury changes to its various forms, often becoming the highly toxic and bioaccumulative methylmercury, the type that builds up in living tissue and increases in concentration up the food chain – including the food we consume. Continue reading

Not Just for Seafood: Mercury Pollution in Montane Ecosystems

By Roberta Attanasio, IEAM Blog Editor

In October 2013, the Minamata Convention on Mercury brought renewed attention to a major global pollution problem known to result in the contamination of seafood and, subsequently, in a variety of health problems in people that consume it. Designed to limit mercury use and emissions internationally, the Convention is only a first step in limiting mercury pollution.
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The Die-Off of Bottlenose Dolphins: Unusual Mortality Events

By Roberta Attanasio, IEAM Blog Editor

During the past year, bottlenose dolphins – known sentinels of ocean health – have been dying at an alarming rate along the US East and Gulf Coasts, albeit for apparently different causes. Along the East Coast, a major cause of death is dolphin morbillivirus, a pathogen related to human measles and canine distemper, which is responsible for an epidemic probably fueled by current lack of immunity and perhaps aided by global warming and pollution – factors that may increase the dolphin susceptibility to infection.
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Microplastic Pollution, Lugworm Health, and Marine Ecosystems

By Roberta Attanasio, IEAM Blog Editor

Lugworm casts

Lugworm (Arenicola marina) casts, by Nick Veitch, licensed under CC BY-SA 3.0

Lugworms (Arenicola marina) live in muddy sand – they’re a component of the food chain and fishermen look for them because they make great bait. Their presence is given away by the piles of sand (casts) deposited above the burrows in which they live. Each burrow has two openings at the surface. The worm draws sand into the burrow through one of the openings and, following digestion, expels the sand through the other opening, thus carrying out its ecosystem engineering duty – sediment turnover – across beaches on both sides of the North Atlantic.
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A Blue Whale’s Earplug Reveals Its Secrets

By Roberta Attanasio, IEAM Blog Editor

Earthworms, swallows, bats, river otters, dolphins, and our pets – these are some of the animal sentinels alerting us to the presence of contaminants in our environment. Now, there is one more species that can be called sentinel – the blue whale.
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Zebrafish: A Toxicologist’s Ally

By Roberta Attanasio, IEAM Blog Editor

Danio rerio, by Thierry Marysael

Danio rerio, photo by Thierry Marysael, licensed under CC BY-NC-ND 2.0

Fishing for the biological effects of contaminants present in the aquatic eco-environment relies, in many instances, on a fish-based model system – the tiny zebrafish, famous for the transparency of its embryos and the remarkable abundance of different transgenic lines. These lines express fluorescent proteins in specific cellular types, or during specific biological processes – because of embryo transparency, the fluorescent, glowing proteins can easily be visualized to detect changes resulting from chemical perturbation.
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Effects of Pesticides on Bird Reproduction: A Novel Model for Risk Assessment

By Roberta Attanasio, IEAM Blog Editor

Like the proverbial canary in the coal mine, many bird populations around the world show signs of trouble—in our specific case not because of gas exposure, but because of pesticide exposure. Unlike the canary in the coal mine, the endpoints for assessing pesticide exposure are not only related to death, but also to a variety of effects that involve the birds’ eggs.
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