toxicology | Southern Fried Science

Chemistry of the Great Big Blue: Sedimentation

Posted on September 21, 2010 by Amy Freitag

Sedimentation in the Chesapeake - look at the brown toward the headwaters. Found at nasa.gov

Rocks erode, travel down rivers and eventually in the form of small particles, settle in river deltas and estuaries. Even smaller pieces can be carried hundreds of miles into the ocean. It’s all part of the natural process of sedimentation, but like many other natural cycles, this one has been hijacked by human activities. Development, agriculture, channelization of streams, damming and many other practices change the natural course of sediment in the coastal oceans more than the ecosystem can handle.

These changes can either be a drastic increase in sediment runoff from upstream sources or a complete deprivation of naturally occurring deltas. In addition, many pollutants cling to these sediment particles so that changing the location of the sediment also shifts the location of pollution.

What’s Killing California’s Sea Otters?

Posted on September 17, 2010 by Andrew Thaler

Sea Otters are turning up dead in central California. In 2007, 11 sea otters were recovered from Monterrey Bay. Over the last three years, dead otters washing up on beaches has reached a record high?

What could be causing all these otter deaths? Are there new predators in the area? Is there some kind of disease? Could increased otter deaths reflect an increase in otter populations, indicating not otter population decline, but otter population growth? The answer turns out to be even more surprising – freshwater algae.

Here no Otter, Sea no Otter, Speak no Otter

Chemistry of the Great Big Blue: Nutrients

Posted on September 7, 2010 by Amy Freitag

The Great Big Blue looks like it contains nothing but water and maybe a little salt, especially out in the open ocean. However, this kind of sparse environment is exactly where the chemistry matters the most – it’s a fine line between not enough, too much, and just right. Given this, there’s no distinct myth here but an underlying unresolved question: what is the limiting factor that keeps the open ocean at low productivity?

Chemistry of the Great Big Blue: Metals

Posted on August 31, 2010 by Amy Freitag

The ocean is full of metals and minerals that naturally occur such as zinc, copper, and cobalt and many marine organisms therefore depend upon access to those metals in small concentrations. However, inshore marine systems receive inputs from industrial, mining, and stormwater runoff that far exceed what these organisms can use. So what’s the effect? There was recently a good review article by Mayer-Pinto et al describings the effects of these metals at the assemblage level that basically did my job for me, research-wise, covering both marine and freshwater systems.

Chemistry of the Great Big Blue: Petroleum Byproducts

Posted on August 24, 2010 by Amy Freitag

In light of the BP oil spill, this week’s installment of Chemistry of the Great Big Blue will be particularly relevant to current events and hopefully already on the minds of everyone reading. Where do petrochemicals in the marine environment come from other than oil spills? Road runoff, refineries, plastic production, plastic degradation, atmospheric deposition and ocean circulation from other parts of the world, natural seeps, and the list goes on and on. It is important to note, however, that oil spills are not necessarily the predominant source of petrochemicals. So what exactly is a petrochemical and what does it do?

Tyrone Hayes, Atrazine, Syngenta, and a little DMX

Posted on August 18, 2010 by Andrew Thaler

Dr. Tyrone Hayes is a professor of Biology at UC Berkley who has been at the forefront of some groundbreaking research into the developmental effects of the pesticide Atrazine on amphibians and mammals. Dr. Hayes runs the Atrazinelovers homepage, a site dedicated to educating the public about the effects of the pesticide on our environment and human health. His research and outreach have earned him the ire of many in the pesticide industry, especially from Syngenta, the company that manufactures Atrazine. The Oyster’s Garter provides a good introduction to his research here.

Below is a video of one of his talks, summarizing his research:

Chemistry of the Great Big Blue

Posted on July 22, 2010 by Amy Freitag

Remember when I promised to profile chemicals in the ocean as a New Year’s resolution? If not, here‘s my first in the series of one posts that resulted, reposted here as a reminder. As always, I encourage checking out the old comments. From now on, I still hope to give the series a second shot at life, so keep checking back for more installments of the series.

As my fellow fry-entists can attest, we know so little about the oceans that every deep sea expedition yields a handful of new species to describe, focus on saving one species may come at the demise of another, and people still won’t go swimming in some areas for fear Jaws will eat them. And that’s just a quick sampling of what we’ve written so far. The depth of our societal ignorance about the ocean and how it functions is enormous. Just as the fishermen of days gone by used to think that the sea offered God’s unlimited bounty, modern day people don’t seem to understand that the ocean isn’t an endlessly large dumping ground for all things undesired in our terrestrial lives. From trash to carbon dioxide to birth control pills, our oceans are the unfortunate downstream victims of human decisions. We don’t understand the impacts, sources, or even types of chemicals that are ending up flushed to the seas. One of my new year’s resolutions is to become more acquainted with the chemicals of the great big sea. Today’s profiled chemical: the unknown. Read More

Sharks and the oil spill on CNN

Posted on June 28, 2010 by David Shiffman

A University of Miami research team that included my friend Austin (seen here posing with Charlie) recently had a CNN team tag along on a shark tagging cruise.

There is also an article on CNN.com, which can be found here

~WhySharksMatter