Monday, February 24, 2014

"Food packaging chemicals may be harmful to human health over long term"

February 2014

"Food Packaging Chemicals May be Harmful to Human Health Over Long Term"
Link: http://www.sciencedaily.com/releases/2014/02/140219205215.htm


     The synthetic chemicals used in the packaging, storage, and processing of foodstuffs might be harmful to human health over the long term. This is due to the fact that most of these substances are not inert and can leach into the foods we eat. Although some of these chemicals are regulated, people who eat packaged and/or processed foods are likely to be chronically exposed to low levels of these substances throughout their lives, and not too much is known about their long term impact.
      Lifelong exposure to food contact materials or FCMs, substances used in packaging, storage, processing, or preparation equipment, "is a cause for concern for several reasons." These include the fact that known toxicants like formaldehyde, a cancer causing substance, are legally used in these materials. Formaldehyde is indeed present, though at low levels, in plastic bottles used for fizzy drinks and melamine tableware. In addition, other chemicals known to disrupt hormone production also show up in FCMs, including bisphenol A, tributyltin, triclosan, and phthalates.

The Restoration of Diverse Sea Meadows

February 2014

The Restoration of Diverse Sea Meadows
Link: http://www.sciencedaily.com/releases/2014/02/140221184758.htm

     A new study shows that placing seedpods in a pearl net, tethered by a rope but still able sway with the tides, may be an especially effective way of restoring eelgrass meadows. "The resulting crop of eelgrass grown for this study was as genetically diverse as the beds from which the seeds were harvested, which San Francisco State University researchers say can make restoration efforts more likely to succeed." Because eelgrass meadows are threatened by a number of human activities, effective restoration plans that maintain diversity are more likely to succeed. Genetic diversity is a relatively new concern in ecosystem restoration projects, where there has been a clear necessity to move plants and animals back into an area as quickly as possible.
     But, eelgrass restoration projects are challenging because it is not easy to plant seedlings under the water, and seeds scattered over a large area have a good chance of being washed away from the restoration site. Instead, Romberg Tiburon Center researchers tested the Buoy Deployed Seeding (BuDS) restoration technique. To begin, the team harvested eelgrass seedpods from several eelgrass beds in San Francisco Bay. Then, they suspended the pods within floating nets over experimental tanks (called mesocosms) supplied with Bay water and with or without sediment from the original eelgrass areas. As the seeds inside each pod ripened, they fell out of the nets and began to grow in the tanks.
     "The researchers then examined "genetic fingerprints" called microsatellites from the plants to measure the genetic diversity in each new crop." This being just one of the many ways to measure genetic diversity. Based on these measurements and others, the new crops were nearly as genetically diverse as their parent grass beds. The research found that the offspring had remarkably maintained the genetic diversity and distinctiveness of their source beds in their new mesocosm environments at the RTC-SFSU lab.
     "Sea grass meadows are a key marine environment under siege. In their healthy state, they stabilize coastal sediment and provide a huge nursery for a variety of algae, fish, shellfish and birds." However, a variety of human influences such as bridge building, runoff pollution and smothering loads of sediment have threatened these grass beds on a global level.

"Marine Algae Can Sense the Rainbow"

February 2014

"Marine Algae Can Sense the Rainbow"
Link: http://www.sciencedaily.com/releases/2014/02/140224171434.htm

     According to new research published in Proceedings of the National Academy of Sciences, several types of aquatic algae can detect orange, green and blue light. Land plants have receptors to detect light on the red and far red of the spectrum, the common wavelengths in the air. These plants sense the light to move and grow as their environment changes. For example, when another plant shades them from the sun, they can move to grow accordingly. However, in the ocean, the water absorbs red wavelengths, instead reflecting colors such as blue and green.
     This study, run by a team of researchers including Canadian Institute for Advanced Research (CIFAR) and Senior Fellow Alexandra Worden, sequenced about 20 different marine algae and found they were able to detect not only red light, but also many other colors. To establish this wavelength detection, collaborators in the lab of J. Clark Lagarias performed biochemical analyses.
     Dr. Worden's lab selected and grew the algae for sequencing in a collaborative effort with CIFAR Fellow Adrián Reyes-Prieto. They "targeted diverse but largely unstudied organisms that might reveal new evolutionary insights into photosynthetic organisms." Dr. Worden' explains the significance of her study: "The phytoplankton in the oceans are, of course, really important to regulating our climate, and we just never knew that they were able to sense our environment in this way."

Unusual Freezing of the Great Lakes

February 2014

Unusual Freezing of the Great Lakes
Link: http://www.sciencedaily.com/releases/2014/02/140219075111.htm

     On February 19, Lake Superior was more than 90 percent iced over, and xperts say it may be covered completely before the end of winter. They are so frozen that someone has proposed to hike across Lake Michigan, and Lake Huron and Lake Erie are 95 percent frozen. Although none of the Great Lakes are completely frozen, the icy lakes are having a major effect on their surrounding environment. 
     Michigan Technological University's Great Lakes Research Center in Houghton has been studying Michigan's snowy Upper Peninsula. "Lake effect snow occurs when weather systems from the north and west pick up evaporating lake water that's warmer than the air, then drop it as snow after reaching land. An ice cover prevents that evaporation."
     Ice on the Great Lakes can also add to more frigid temperatures because warmer lake water will not have a chance to gauge the temperatures of those same northerly weather systems the way it usually does. However, the ice can also have positive effects. Lake Superior's whitefish and some other fish need ice cover to protect their spawning beds from winter storms. Heavy ice, therefore, will lead to good fishing.