Dear Friends/Co-sailors,
Sharing in today’s pick section a news about study that has
found out some bitter chemical pollution truths in rivers of Pennsylvania in
the USA. These issues should also worry
us, rather more because our pollution studies are too sporadic and immature at
the moment. I am sure if a thorough
study is done on these aspects most of our rivers would be showing similar
problems in our fishes.
This study should warn us about the estrogenic chemicals in
our water. Let’s watch out for it, let’s
find ways to curb the pollution.
Hope you will find the issue useful.
Thanks and regards,
Ranjan
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Intersex fish indicate chemical problems in Pennsylvania rivers
SANDY BAUERS, INQUIRER STAFF WRITER
LAST UPDATED: Wednesday, July 16, 2014
A government researcher who has studied intersex fish in the
Potomac River now has found them in three Pennsylvania river basins, including
the Delaware.
The fish - males that develop immature eggs and other signs
of feminization - are considered symptomatic of estrogenic chemicals in the
water. Their discovery in the state indicates that effects of hormones and
hormone-like compounds are more widespread than thought.
The mutant fish could bespeak a deeper crisis, said Vicki
Blazer, a U.S. Geological Survey fish biologist who conducted the Pennsylvania
study. "Fish are a good indicator of the health of the aquatic
environment," she said. "They are always in it."
Pharmaceuticals and personal-care products - contaminants
that, while being detected worldwide, are unregulated in water - are a growing
concern for water-quality experts.
The Pennsylvania intersex fish discoveries have prompted the
state Department of Environmental Protection to launch a sampling campaign of
several river systems in search of 180 compounds, including
endocrine-disrupting chemicals, new pesticides, and old products such as DDT.
The Delaware River Basin Commission and partner researchers
also have found caffeine, over-the-counter products such as naproxen and
ibuprofen, prescription drugs such as codeine, and antibiotics.
Natural and synthetic hormones rank among the top chemicals
in U.S. surface waters for potential ecological harm, a 2012 DRBC report noted.
"We have to be vigilant," said Thomas Fikslin,
manager of the commission's monitoring and modeling branch. "It's why we
do the monitoring we do, to see first of all what chemicals are there, and then
determine potential hazards to human health and aquatic life."
But, he added, "Just because you measure something in
high concentration doesn't mean it's a problem." Conversely,
"measuring something in a low concentration doesn't mean it's not a
problem."
Intersex fish are a problem.
In the latest study, Blazer tested smallmouth bass and
suckers in the Ohio, Susquehanna, and Delaware watersheds.
Suckers, which are bottom-feeders, showed few intersex
characteristics. But the bass from all sites had immature eggs in their testes.
Blazer found the highest prevalence and severity in the
Susquehanna drainage area. But at the Falls Bridge over the Schuylkill near
East Falls, 50 percent of the smallmouth bass they caught had intersex
characteristics.
Blazer and her colleagues also used a specific strain of
yeast to measure estrogenicity in the water. In places with intersex fish, it
was higher.
The sources of the estrogenic chemicals, Blazer said,
"are likely complex mixtures from both agricultural sources, such as
animal wastes, pesticides, and herbicides, and human sources, [such as] waste
water treatment plants and other sewage discharges."
In most cases, Blazer said, farmers are not feeding
estrogenic compounds; manure simply contains them. In addition, pesticides and
herbicides can be estrogenic.
Likewise, humans naturally excrete estrogens, as well as the
synthetic estrogens from birth control pills. The latter "tend to be of
higher potency," she said, "and are more stable, and hence, last
longer in the environment."
Generally, Blazer found that severe intersex characteristics
occurred downstream of waste water treatment plants. The Schuylkill has 435.
Most facilities are not designed to remove pharmaceuticals that people ingest,
then excrete.
Agricultural land use, however, could be the bigger culprit.
Overall, both the numbers of intersex fish and immature eggs correspond with
the amount of agriculture in the watershed above the collection sites. In
upstream areas along the Schuylkill, the percentage of land given over to
farming is high.
The study findings, published recently online by the journal
Environmental Monitoring and Assessment, were not good news to Tom Davidock,
who oversees the Schuylkill Action Network, an educational and outreach program
of the Partnership for the Delaware Estuary. He often works with farmers to
help them reduce their environmental impacts, and "this is just another
one of those messages we'll have to start looking into," he said.
Blazer did not start out looking for intersex fish. When she
began working the Potomac, she was investigating fish kills in the watershed.
But she soon began finding male fish with immature eggs and a precursor to yolk
material.
Similarly, fish kills in the Susquehanna are what attracted
the interest of the Pennsylvania DEP. First-year smallmouth bass were getting
sick and dying late every summer.
After state officials learned of Blazer's work, they began
their own testing program for emerging contaminants in 2013. They are sampling
the waters not just of the Susquehanna, but also the Delaware, Allegheny,
Juniata, and Youghiogheny Rivers.
Although smallmouth bass are the immediate concern, they may
simply be an early indicator of "bigger problems in the river," said
Rod Kime, a DEP environmental program manager.
"We're finding concentrations of many of these
compounds," Kime said, but he called that "not unusual" in
"any place there are people or farms."
Source: http://www.philly.com/philly/news/science/20140716_Intersex_fish_indicate_chemical_problems_in_Pa__rivers.html#c5dkxMCQubsRRObY.99
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