[health-vn] Feature: Pesticide Use Linked to Birth Defects

[Vern Weitzel]

Subject: 	Feature: Pesticide Use Linked to Birth Defects
Date: 	Sun, 19 Apr 2009 09:41:45 -0700
From: 	Yahoo Group <ashwani.vasishth at gmail.com>
Reply-To: 	envecolnews-owner at yahoogroups.com
To: 	Environmental Ecology News <envecolnews at yahoogroups.com>


http://www.loe.org/shows/segments.htm?programID=09-P13-00016&segmentID=1

*Pesticides and Birth Defects
*     In the spring and early summer, levels of pesticides in water
increase. One weed killer in particular, Atrazine, shows up in
surprisingly high amounts. Host Steve Curwood talks with Dr. Paul
Winchester to learn why babies conceived between April and July may be
more likely to develop birth defects.

Air Date: Week of April 17, 2009

CURWOOD: From the Jennifer and Ted Stanley Studios in Somerville,
Massachusetts - this is Living on Earth. I'm Steve Curwood.

YOUNG: And I'm Jeff Young in Washington.

When crops go in the ground and start to grow, it's the time for
conventional farmers to apply chemical weed killers.

For example, millions of pounds of Atrazine are applied on US farms each
year, even though the herbicide is banned in Europe.

And it should not be surprising that between April and July, there tend
to be higher levels of pesticides in water than during the rest of the
year, as the U.S. Geological Survey has found.

CURWOOD: What is surprising is new research that shows an association
between the time of conception, pesticide levels, and the likelihood of
crippling or fatal birth defects.

The research is being led by Paul Winchester, a neonatologist. His
curiosity was aroused when he encountered a high level of birth defects
when he began working in the heart of farm country at St. Francis
Hospital in Indianapolis.

Dr. Winchester, what exactly did you find?

WINCHESTER: We found that birth defects like spina bifida, cleft pallet
and lip, down syndrome, urogenital abnormalities, club foot among others
are some of the birth defects that are more likely to occur for women
who conceive between April and July. That time period coincides quite
well with the time period when surface waters measured across the U.S.
are having significantly more pesticides in their concentration than any
other times of year.

CURWOOD: As a neonatologist, you must be seeing some of these children
who have quite extensive urogenital defects. How true is that of your
practice?

WINCHESTER: Well, the urogenital problems that are the most common are
those that effect male genitals, hypospadias is a good example and
undescended testicles. Both of these are now known to be linked to
exposures of chemicals in utero - not just pesticides, but some of the
other chemicals as well. Almost all of these chemicals can act in a way
that is similar to estrogen either by blocking testosterone or by
augmenting estrogen signaling. And of course that's anathema to the
normal development of a male genital.

CURWOOD: And how much of that are you seeing?

WINCHESTER: Well we do see a lot of it. Probably the most striking
things that's happened to us this last month, which is the month when
babies conceived in June are delivering is that it seems that we have
seen kind of one of everything. We've seen in a small hospital,
community hospital setting, we've seen major birth defects that range
from chromosome anomalies, spina bifida, adactyly, cleft pallet and lip
- we're just struck by the fact that this research appears to be right
on, this month.

CURWOOD: How much did this research cost you and how did you pay for it?

WINCHESTER: Well we're a non-funded research program. I kinda grew up on
a farm in Montana where when you see the fences broke you just grab a
fence post and a pair of pliers and go and fix it. And you hope that if
you're over there the neighbors will notice and give you a hand. And
pretty much that's how this research has been done. And I sometimes
wonder if I had been funded whether this question would have been asked.

CURWOOD: Which question is that?

WINCHESTER: That is the number one cause of infant deaths turns out to
have a higher risk occurrence in women who conceive between April and
July. I kind of wonder why that's news. And so, in a sense, we like to
ask this large question, because we now know some things in rats and
amphibians and alligators that these pesticides are in fact changing
them because of fetal exposure. And we don't have enough time to sort
this out before perhaps we could have harmed generations of children.

CURWOOD: Now you say we need to look at the down stream effects of
pesticide exposure - what do you mean exactly by that?

WINCHESTER: Probably one of the most important investigators in this
area is a man named Michael Skinner who has shown us that the capacity
that pesticides have to alter our lives has been grossly underestimated.
In his model a pregnant rat is exposed for just a brief period in the
very first phase of pregnancy to one pesticide. Keep in mind that there
are no children in America who are exposed to just one pesticide. The
average child is exposed to 300 chemicals at the time of conception. But
in his model with just one pesticide all the rat babies when they were
born did not have any birth defects at all. They looked perfectly
normal. That's really important to think about because had the
experiment ended there, it would have been declared a safe exposure, not
associated with any harm. As he likes to point out, thanks to some
inquiring minds he was allowed to keep his experiment going long enough
to see how these rats turned out as adults. And there he found that
ninety percent of the males were afflicted by a whole host of disorders
that we would refer to as adult disorders, adult diseases. They included
conditions like low sperm count and infertility, immune disorders,
kidney and prostate problems, cancer, high cholesterol and a shortened
life span. And if that sounds bad, it's really not as bad as the rest of
the experiment. Because the rest of the experiment showed that this
condition could be transferred to all subsequent generations without any
further exposure. So if one pesticide could do this, imagine what might
be happening in our society.

CURWOOD: What do you tell your patients, people who are thinking about
having children, what about conceiving during the beginning of the
growing season, this April to July period that seems to increase the
risk of birth defects?

WINCHESTER: Well, based on our current evidence we certainly can't prove
to you that it would be safer for you to avoid those time periods but
based on the current level of knowledge, if you have a choice, why not
try conceiving at some other time. We happen to notice that the time
associated with the lowest birth defect rate is also the time when women
are most likely to have a successful pregnancy and that turns out to be
December in the U.S. So the spring tends to be a high-risk period for a
lot of different complications of pregnancy and this may be more
relevant to some than others.

CURWOOD: Dr. Paul Winchester is a neonatologist at St. Francis Hospital
in Indianapolis. Thank you so much, sir

WINCHESTER: Thank you.

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