News Article

MBL scientist investigates role of environmental toxin in shell disease

MBL, WOODS HOLE, MA—The search for what causes a debilitating shell disease affecting lobsters from Long Island Sound to Maine has led one Marine Biological Laboratory (MBL) visiting scientist to suspect environmental alkyphenols, formed primarily by the breakdown of hard transparent plastics.

Preliminary evidence from the lab of Hans Laufer suggests that certain concentrations of alkyphenols may be interfering with the ability of lobsters to develop tough shells. Instead, the shells are weakened, leaving affected lobsters susceptible to the microbial invasions characteristic of the illness.

"Lobsters 'know' when their shell is damaged, and that's probably the reason when they have shell disease, why they molt more quickly," says Laufer, a visiting investigator at the MBL for over 20 years and professor emeritus of molecular and cell biology at the University of Connecticut. "But ultimately, they still come down with the disease. And we think the presence of alkyphenols contributes to that."

Like any crustacean, lobsters shed their shells multiple times in one lifetime. After molting, the outer skin of the soft and exposed lobster will begin to harden. It is here that Laufer thinks the alkyphenols are doing their damage. At this point, a derivative of the amino acid tyrosine, whose function is to harden the developing shell, is incorporated. It is known that alkyphenols and tyrosine are similarly shaped and Laufer suspects that the toxin may be blocking tyrosine from its normal functions. He is at MBL this summer to measure the amount of competition between the two molecules. Alkyphenols are also known to act as endocrine disruptors.

Laufer discovered the presence of alkyphenols in lobsters serendipitously while investigating a tremendous lobster die off at Long Island Sound in 1999, when shell disease, first observed in the mid-1990s, was noted to be on the rise. Although an unusually hot summer, it was also the first time New York City sprayed mosquito populations to prevent the spread of West Nile virus. Laufer, who began his career as an insect endocrinologist, suspected the toxins from the sprayings may have contributed to the lobster die off. In 2001, while searching for the mosquito toxins in lobsters, he instead found alkyphenols.

"It's a real problem," Laufer says. "Plastics last a long time, but breakdown products last even longer. Perhaps shell disease is only the tip of the iceberg of a more basic problem of endocrine disrupting chemicals in marine environments."

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The MBL is a leading international, independent, nonprofit institution dedicated to discovery and to improving the human condition through creative research and education in the biological, biomedical and environmental sciences. Founded in 1888 as the Marine Biological Laboratory, the MBL is the oldest private marine laboratory in the Western Hemisphere. For more information, visit www.MBL.edu.

 

its so scientific for this simple brain- but I get it! :think:

 

So, is their hypothesis that plastics contribute to shell diesiese? I thought I read about that somewhere. Does it affect hermies? :angel12:

 

Don't know, hermit crabs are crustaceans but the study was only on lobsters. Hermit crabs do get shell disease, hopefully they will research more.

 

MY hypothesis is that plastics can harbor bacteria, which in turn would lead to an infection (IE, the cat's bowls were all plastic, and i had them for three years. I began to notice lots of ugly blackheads all over thier chins. I made the switch to metal pans, and thier faces have all cleared up)

 

:whaaaat: I agree with Hermez, that's alot of scientific jaw for me. I understand also. And I agree with Mad, plastics do harbor alot of bacteria. I have the link of a web site at HCRU where it talks about these sientists who have done studies and have found that hermit crabs are having a hard time finding shells on beaches. They think that it is becoming such a problem that they have created these plastic "homes" for them to wear like a shell. It might work...or just cause more problems for those little babies. They might end up getting bacterial infections and dieing off. That's scary. These marine biologist have scared these all over beaches of North America. Is that litering??? :eeeek:

 

ops2: oops! :sarcastic: The last sentence that said "scared all over the beaches" was supposed to be "scattered all over the beaches". :dork2: :hahahaha: :chuckle: :biglaugh:

 

Do you think there is a connection between discarded plastic and sea snails? If there are not enough shells on the beach, one reason may be that too many people collect them. Knowing this, though do you think the pollution is damaging the sea snail population so that the snails are dying before they have the chance to make sturdy, large shells? Food for thought, anyway. mg:

 

A couple years ago I read an article about how pervasive plastic is. I have a fascinating article on plastics that I hope you don't mind me posting here.

Plastic was only invented in the 50's. ALmost every bit of plastic that was ever created is still around in some form. Plastics are made from chemicals and there is proof now that as those chemicals break down, they release harmful toxins. I am sure that they can possibly affect and kill crustaceans, along with other critters.

Bits of plastic have even been found within fish caught as human food!

Here is the article. If it's inappropriate feel free to remove it.

http://www.orionmagazine.org/index.php/articles/article/270/