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Vanessa Ward

Endocrine Disruptors and the Obesity Epidemic -- Heindel 76 (2): 247 -- Toxicological S... - 1 views

toxsci.oxfordjournals.org/...247

obesity endocrine disruption

shared by Vanessa Ward on 25 May 10 - Cached
  • "We are faced with the seeming paradox of increased adiposity at both ends of the birth weight spectrum—higher BMI with higher birth weight and increased central obesity with lower birth weight" (Oken and Gillman, 2003). Thus prevention of childhood and adult obesity must start in utero.
  • Indeed, many synthetic chemicals are actually used to increase weight in animals.
  • This article provides fascinating examples of chemicals that have been tested for toxicity by standard tests that resulted in weight gain in the animals at lower doses than those that caused any obvious toxicity.
  • ...7 more annotations...
  • Chemicals having endocrine-disrupting activity rise to the top of the list as most act via receptors linked to activation of transcriptional activity.
  • In the adult, loss of circulating estrogen due to ovariectomy leads to increased body and adipose tissue weights. Estrogen receptor alpha knockout mice have a significantly increased body fat content, and estrogen decreases the activity of lipoprotein lipase
  • estrogenic endocrine-disrupting chemical bisphenol A at concentrations as low as 2 µg/ml, in the presence of insulin, stimulated differentiation of the 3T3L1 cells into adipocytes
  • he fact that an environmental chemical has the potential to stimulate growth of "preadipocytes" has enormous implications for the area of obesity and its control.
  • Differentiation could be inhibited and more potential fat cells could be formed, as seems to be the case with NP, or differentiation could be stimulated, as appears to be the case with BPA
  • Will these results extrapolate to the in vivo situation in rodents and other animal models?
  • Only time and more research will tell, but the door has been opened by the novel work being highlighted.
  • Vanessa Ward on 25 May 10
     
    An article discussing how the area of research of obesity as a result of endocrine disrupting chemical exposure could be a beneficial area for intervention and prevention studies of obesity. This was one of the first articles I found directly addressing how endocrine disrupting chemical exposure can lead to a predisposition to obesity
Liz Richardson

Environmental Signaling: What Embryos and Evolution Teach Us About Endocrine Disrupting... - 0 views

edrv.endojournals.org/...319

environmental EED estrogen

shared by Liz Richardson on 08 Jun 10 - Cached
  • Liz Richardson on 08 Jun 10
     
    An overview of many endocrine disrupting chemicals, useful to anyone looking into the effects of environmental chemicals on organisms. Reference made to a book titled "Hormonal Chaos", by Sheldon Krimsky, describing how industrial and agricultural chemicals contact organisms and disrupt hormone function. Specifics on effects of environmental estrogens and fetal development.
suwhitte

Endocrine Disruption Prevention Act of 2009 - 0 views

www.fisheries.org/...ruption-prevention-act-of-2009

fish EED

shared by suwhitte on 25 May 10 - Cached
  • suwhitte on 25 May 10
     
    A letter from the American Fisheries Society to Obama asking him to support the Endocrine Disruption Prevention Act of 2009.
Vanessa Ward

San Francisco Medical Society | The Weight of Evidence - 0 views

www.sfms.org/...Template.cfm

SFMS Blumberg Grun obesity epidemic endocrine disruption EDCs obesity

shared by Vanessa Ward on 11 Jun 10 - Cached
  • “leading to neglect of other plausible mechanisms and well-intentioned but potentially ill-founded proposals for reducing obesity rates”
  • Since publication of that review, substantial evidence has emerged that increases the plausibility of one of the alternative mechanisms suggested by Keith et al: disruption of weight regulation by endocrine-disrupting chemicals (EDCs) in the environment.
  • Concerns about the potential contribution of EDCs to childhood obesity build from two considerations, one out of human biology and the other from animal experiments
  • ...7 more annotations...
  • Prior
  • toxicologists were concerned more with weight loss, which was seen as an adverse outcome.
  • Many of these chemicals alter the behavior of specific genes that are involved in determining the number of fat cells (adipocytes) an individual will have as an adult.
  • he list of contaminants implicated by animal studies is substantial, including several estrogenic EDCs such as DES, bisphenol A, soy phytoestrogens
  • Almost no human data are available to test the obesogen hypothesis in people. No epidemiological evidence exists, because the hypothesis is so new
  • One in vitro experiment, however, has demonstrated that exposure to obesogens increases the rate of conversion of human stem cells to adipocytes (Kirchner et al 2010), confirming the validity of the basic mechanism and the relevance of the animal studies to people.
  • That would be a big win for medicine and public health.
  • Vanessa Ward on 11 Jun 10
     
    San Francisco Medical Society discusses the possible relationship between chemical exposure and the obesity epidemic.
Anna McLean

Our Stolen Future: New science on the impacts of endocrine disruptors on brain and beha... - 0 views

www.ourstolenfuture.org/...behav.htm

shared by Anna McLean on 08 Jun 10 - Cached
  • The sex steroids (testosterone, estrogen, etc.) contribute to, among other things, sexual differentiate of brain centers, and thereby, to the development of sexual identity and sexual behaviors
  • A rapidly increasing body of scientific research is revealing mechanisms of action, demonstrating impacts of disrupted development, and exploring links between intelligence, behavior and contamination experienced in the womb. What is emerging from this research is that brain and behavior are likely to be the most sensitive endpoints vulnerable to endocrine disruption. Many synthesized compounds in commercial use today, moreover, can derail neurological development.
  • April 2003. Exposure in the womb to extremely low levels of bisphenol A alters sexual differentiation of the brain and behavior in rats. More...
  • ...2 more annotations...
  • September 2002. Dutch scientists report that boys exposed prenatally to higher levels of PCBs and dioxin are more likely to show demasculinized play behaviors. Girls and boys exposed to modestly elevated dioxin levels demonstrate more feminized play behaviors. The scientists suggest that that these alterations in play result from endocrine disruption of the development of sex-specific behaviors. More...
  • disturbed sexual differentiation of reproductive behavior, potentiating the expression of feminine sexual behavior and reducing masculine behavior."
  • Anna McLean on 11 Jun 10
     
    This document is the web site for the book titled Our Stolen Future. There are numerous sections with "more..." links to full pages on the summarized topic. This is a great tool for my project.
  • Anna McLean on 11 Jun 10
     
    Highlighted text indicates areas applicable to my topic.
Anna McLean

NRDC: Endocrine Disruptors - 0 views

www.nrdc.org/...qendoc.asp

shared by Anna McLean on 11 Jun 10 - Cached
  • 5. Should humans be concerned for their health based on evidence that fish, birds and alligators have been affected? Yes. All vertebrates (fish, amphibians, reptiles, birds, and mammals, including humans) are fundamentally similar during early embryonic development. Scientists can therefore use the evidence acquired on other species to make predictions about endocrine disrupting effects on humans.
  • 6. Is there direct evidence that humans are susceptible to endocrine disruption?
  • 8. These days don't chemicals have to be safe to be allowed on the market? No.
  • Anna McLean on 11 Jun 10
     
    Frequently asked-type questions
  • Anna McLean on 11 Jun 10
     
    Obviously, this site is for the general public. But, it could be a useful link for your webpages if you want some basic background information to persuade people that this IS relevant to them and their families.
Vanessa Ward

Epigenetics, Evolution, Endocrine Disruption, Health, and Disease -- Crews and McLachla... - 1 views

endo.endojournals.org/...s4

shared by Vanessa Ward on 22 May 10 - Cached
  • Endocrine-disrupting chemicals (EDCs) in the environment have been linked to human health and disease. This is particularly evident in compounds that mimic the effects of estrogens.
  • information recently uncovered, regarding mechanisms of endocrine and environmental signaling, to explore the role of the environment in health and disease.
  • Vanessa Ward on 22 May 10
     
    This a good article that gives a general overview of EDC's and the role they play in the compromise of physical and mental health. One particularly interesting thing is how a discussion of EDC's and evolution is presented.
suwhitte

Gordon Research Conferences - 2010 Program (Environmental Endocrine Disruptors) - 0 views

www.grc.org/programs.aspx

shared by suwhitte on 20 May 10 - Cached
  • suwhitte on 20 May 10
     
    At this upcoming conference and past conferences (see conference history), top scientists, studying endocrine disruption effects on humans and wildlife, meet to share the latest findings. Look over the program for topics and scientists - may be useful in identifying a topic for your project. I have attended two of these conferences and they were excellent and very current.
suwhitte

frontline: fooling with nature: interviews: theo colborn - 0 views

www.pbs.org/...colborn.html

shared by suwhitte on 20 May 10 - Cached
  • suwhitte on 20 May 10
     
    Interview with Theo Colburn author of Our Stolen Future and one of the discoverers of the phenomenon of endocrine disruption.
Anna McLean

A list of endocrine-disrupting compounds - 0 views

www.ourstolenfuture.org/...chemlist.htm

shared by Anna McLean on 11 Jun 10 - Cached
  • Anna McLean on 11 Jun 10
     
    A useful list of compounds that includes the hormone system affected and mechanism. This would be a useful tool because each compound section has a references section where you may find other useful sources for your projects.
Anna McLean

Would you like lemon, or BPA with your water? - 0 views

likeafishinwater.com/...e-lemon-or-bpa-with-your-water

shared by Anna McLean on 11 Jun 10 - Cached
  • The only problem was that vinyl products generally contain significant amounts of Bisphenol-A (BPA), a plastic additive, exposure to which causes disruption of endocrine hormones
  • BPA in plastic baby bottles
  • What makes BPA such a problem? It affects everyone, but developing fetuses and small children are particularly vulnerable.
  • ...2 more annotations...
  • It alters the levels of endocrine hormones, which has effects ranging from learning disabilities to diseases and altered sexual development.
  • BPA is currently banned in Chicago, the State of Minnesota and Suffolk County, NY.
Anna McLean

Gender Benders & Endocrine Disruptors around You - 0 views

www.herplace.com/...gender-benders.htm

shared by Anna McLean on 08 Jun 10 - Cached
  • Some Health Consequences of DES
  • Timeline of Synthetic Endocrine Disruptors (POPs)
  • Mechanisms of Endocrine Disruption
  • Anna McLean on 11 Jun 10
     
    General ED site. Touches on consequences of DES use in offspring of the using mother. Includes a useful timeline of POP use
suwhitte

TEDX - The Endocrine Disruption Exchange - 0 views

www.endocrinedisruption.com/home.php

EED general

shared by suwhitte on 16 May 10 - Cached
  • suwhitte on 16 May 10
     
    Site started by Theo Colburn, author of "Our Stolen Future."
Vanessa Ward

Endocrine Disruptors IV: Cancer in Our Foods - 1 views

www.nativeshop.org/...8-endocrine-disruptors-iv.html

shared by Vanessa Ward on 22 May 10 - Cached
  • Polycyclic aromatic hydrocarbons (PAHs) are a group of compounds that include over one hundred different contaminants
  • PAHs are persistent compounds. They are not easily broken down, so they can last for a long time. Also, they bioaccumulate—the higher up in the food chain you go, the higher the concentration of PAHs within the organism.
  • To be safe, there are several ways of reducing exposure to PAHs
  • Vanessa Ward on 22 May 10
     
    I thought this was an interesting introductory site to PAH's and how they relate to endocrine disruption. The main focus is on PAH's, which are the result of incompletely burned material such as coal, wood, oil, or gas. Eating grilled foods could increase the exposure to PAH's as well as cigarette smoke, exhaust and even natural sources such as forest fires. Exposure to PAH's could lead to the development of cancer.
suwhitte

Environment and health: 6. Endocrine disruption and potential human health implications... - 0 views

www.cmaj.ca/...1471

shared by suwhitte on 20 May 10 - Cached
  • suwhitte on 20 May 10
     
    link to a pdf of a review article on endocrine disruptors and human health. A nice overview of the field.
suwhitte

EUROPA - Environment - Endocrine disrupters - 0 views

ec.europa.eu/...index_en.htm

shared by suwhitte on 20 May 10 - Cached
  • suwhitte on 20 May 10
     
    Check out how other countries are regulating EEDs.
srom88

Pesticide Mixtures, Endocrine Disruption, and Amphibian Declines: Are We Underestimatin... - 1 views

www.ncbi.nlm.nih.gov/...PMC1874187

shared by srom88 on 24 May 10 - Cached
  • In addition to having highly permeable skin (which makes amphibians particularly vulnerable to chemical contaminants), amphibians also typically reproduce and pass through critical hormone-regulated developmental stages while in the aquatic environment
    • srom88
      srom88 on 24 May 10
       
      What about human skin and its permeability to these pesticides?
  • atrazine is of special concern because it is a ubiquitous, persistent contaminant of ground-water and surface water that is active at low, ecologically relevant concentrations
    • srom88
      srom88 on 24 May 10
       
      Atrazine is common pesticide used; definite possibility for a focus.
  • realistic pesticide mixture composed of chemicals applied to cornfields in York County, Nebraska.
    • srom88
      srom88 on 24 May 10
       
      Can also find different experiments in different locations in the US or even out of the country.
  • ...32 more annotations...
  • Radioimmunoassay
    • srom88
      srom88 on 24 May 10
       
      very sensitive technique used to measure concentrations of antigens (for example, hormone levels in the blood) without the need to use a bioassay.
  • With the exception of metalaxyl, no single compound affected mortality
  • mortality was 4% for animals exposed to single pesticides (range = 0–7.8%), with the highest mortality (7.8%)
  • Propiconizole significantly delayed time to initiate metamorphosis (FLE; F = 2.72, df = 10, p = 0.003) and time to complete metamorphosis (TR; F = 2.81, df = 10, p = 0.002) relative to controls (Figure 1).
  • Animals exposed to pesticide mixtures at 0.1 ppb had significantly longer larval periods: initiation of metamorphosis (days to FLE) was delayed
  • there was a significant effect on SVL at metamorphosis (F = 2.1, df = 10, p < 0.05; Figure 3). The smallest animals to metamorphose were those exposed to cyfluthrin, tebupirimphos, or atrazine
  • All the mixtures (0.1 ppb each pesticide) retarded growth
  • For the pesticide mixtures, 0.1 and 10 ppb atrazine + S-metolachlor resulted in a negative but nonsignificant relationship between TR and SVL, whereas 0.1 and 10 ppb Bicep II Magnum exposure resulted in maintenance of the positive relationship between TR and SVL, but the relationship was significant for the 0.1 ppb concentration only
    • srom88
      srom88 on 24 May 10
       
      Different combinations of pesticides will affect the organism differently.
  • Histologically, presumptive males maintained both a cortex and a medulla separated by connective tissue without clear formation of testicular lobules (e.g., undifferentiated), whereas females showed regression of the gonadal medulla and an ovarian vesicle but lacked significant numbers of developing oocytes in the cortical regions of the gonad
  • Seventy percent of the animals exposed to the nine-compound mixture were unable to sit upright. Exposure to the nine-compound pesticide mixture was associated with meningitis, otitis interna, and septicemia due to the gram-negative, water-borne bacteria Chryseobacterium (Flavobacterium) menigosepticum
  • Morbidity and mortality rates in animals treated with the nine-pesticide mixture were significant (G = 100.12, df = 4, p < 0.001) compared with those in controls or the other mixtures (all of which showed a 0% incidence) and reached 70% of the 59 animals that survived to complete metamorphosis in animals exposed to the pesticide mixture.
  • After noting that animals exposed to the nine-compound mixture contracted flavobacterial meningitis (see above “Flavobacterial response”), we examined the condition of the thymus as an estimate of immune function.
  • Although a sizable database examining the toxicological effects of pesticides on amphibians exists (Pauli 2004), most of these studies examine acute toxicity, morbidity, and mortality only
  • We demonstrated that a realistic pesticide mixture (based on a mixture applied to an actual field) at low ecologically relevant concentrations can have dramatic effects on amphibian development and growth, and ultimately (we predict) survivorship
  • one of these compounds (propiconizole) retards larval development and delays metamorphosis, and two others (tebupirimphos and cyfluthrin) retard larval growth. In addition to these new data, the present study confirms the retardation of amphibian development
  • Atrazine has a number of well-documented adverse effects on amphibian larvae. It is a potent endocrine disruptor that both chemically castrates and feminizes exposed male amphibian larvae and also retards larval development and growth
  • It also induces edema (Carr et al. 2003), erratic swimming (Carr et al. 2003), and irregular behavioral activity (Rohr and Palmer 2005) and is an immunosuppressant (Christin et al. 2003; Gendron et al. 2003; Kiesecker 2002) in amphibians.
  • As one of the world’s most commonly applied pesticides, it is the most common contaminant of groundwater and surface water
  • effects of atrazine on the gonads were not detectable because individuals from the present population do not complete sexual differentiation of the gonads before metamorphosis
  • retardation of growth and development was more severe when atrazine was combined with other pesticides (e.g., S-metolachlor), and the nine-pesticide mixture had the most severe impact.
  • amphibians (including leopard frogs) often breed in temporary water sources
  • Retardation of growth is also detrimental. Smaller size at metamorphosis limits food availability for newly metamorphosed frogs, which are gape-limited predators (Figure 12A). Further, smaller individuals are more susceptible to predators, which may also themselves be gape-limited predators
  • esticide mixtures retard growth and size at metamorphosis, exposed amphibians are less likely to find food and more likely to be preyed upon. Also, decreased size at metamorphosis combined with subsequent decreased postmetamorphic growth decreases the chances that amphibians will survive overwintering
  • alteration of the relationship between time to metamorphosis and size at metamorphosis is even more significant than either measured alone. In amphibians, the larval stage is a period of growth. A
  • pesticides that produce no effects alone may act as “enhancers” that worsen the effects of pesticides that act as “effectors” when the two groups of chemicals are combined.
  • characterize pesticide interactions as concentration additive or response additive
  • Pesticide-induced declines in populations as a result of decreased prey availability and increased susceptibility to predators (as a result of decreased size and the negation or reversal of the relationship between time to metamorphosis and size at metamorphosis) may be difficult to discern in the wild. Perhaps more important, emergent diseases caused by agents such as ranavirus
  • and chytrid
  • are considered major contributors to amphibian declines
  • the effects of atrazine on sex differentiation can negatively affect amphibian population
  • trazine has been shown to increase disease rates and parasite loads in amphibians by several pathogens
  • including the trematode associated with development of limb deformities
cmccleery1

Endocrine disruption in fish - Google Books - 0 views

books.google.com/books

general

shared by cmccleery1 on 24 May 10 - Cached
  • cmccleery1 on 24 May 10
     
    This is a google preview of a book which is about how the endocrine system is obstructed nad affected in fish
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