[Pharmwaste] UC Davis researcher finds contamination in striped bass
dldebiasi at deq.virginia.gov
Wed Dec 10 14:02:54 EST 2008
UC Davis researcher finds contamination in bass
By Chris Bowman
cbowman at sacbee.com
Published: Tuesday, Dec. 09, 2008 | Page 3B
Striped bass in the San Francisco Estuary are producing deformed
offspring as a result of contamination from a mix of pesticides,
industrial chemicals and flame retardants, scientists have found.
A team of University of California, Davis, researchers reported "a
conclusive line of evidence" that bass are accumulating these persistent
chemicals and passing them to their young.
The recently published findings add to a growing body of evidence that
pollution in the estuary is contributing to the collapse of fish
populations, along with introduced clams, wastewater from sewage
treatment plants and massive water exports to Southern California.
The findings have implications for people because the estuary is a
source of drinking water for 25 million Californians and most farms in
the state, said David Ostrach, a research scientist at the UC Davis
Center for Watershed Sciences.
"If the fish living in this water are not healthy and are passing
contaminants to their young, what is happening to the people who use the
water, are exposed to the same chemicals or eat the fish," Ostrach said
in a news release Monday.
Using new analytical methods, the researchers found that the days-old
offspring of estuary bass had significantly smaller brains and livers,
curved spines and far less protein-rich yolk in their sacs to survive,
compared with larvae from hatchery bass raised in clean water.
"Just before first feeding these larvae had virtually no source of
energy available to search for food or avoid predators," Ostrach said.
The findings, published online Nov. 24 in the Proceedings of the
National Academy of Sciences, add to evidence that highly toxic
pesticides abandoned years ago are still working their way up aquatic
food chains and causing damage.
Though the pesticide DDT and industrial coolants called polychlorinated
biphenyls or PCBs were banned more than 30 years ago, these chemicals
were found at significant levels in the eggs from the estuary fish, the
Eggs from the control group of hatchery-reared female bass had only
comparatively minuscule levels of contaminants that researchers
attributed to the hatchery food that contained ground fish.
The bass research is part of an ongoing series of studies by a large
team of university and government scientists to determine the role
contaminants play in the ecological collapse of the estuary. Striped
bass, once part of a thriving commercial and sport fishery, have
steadily declined in the past 30 years along with the Delta smelt, the
longfin smelt and the threadfin, said Ostrach, who has studied the
declines since 1988.
The flame retardants, called PBDEs or polybrominated diphenyl ethers,
are long-lived and are accumulating in humans. Recent studies have shown
that Californians have double the amount of these retardants in their
blood as the national average and hundreds of times greater in the
breast milk of Bay Area mothers than those elsewhere in the world.
The chemicals are are still found in upholstery, carpeting textiles,
paint and electronic insulation. The consequences of PBDE contamination
are largely unknown.
Call The Bee's Chris Bowman, (916) 321-1069.
Deborah L. DeBiasi
Email: dldebiasi at deq.virginia.gov
WEB site address: www.deq.virginia.gov
Virginia Department of Environmental Quality
Office of Water Permit Programs
Industrial Pretreatment/Toxics Management Program
PPCPs, EDCs, and Microconstituents
Mail: P.O. Box 1105, Richmond, VA 23218 (NEW!)
Location: 629 E. Main Street, Richmond, VA 23219
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