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suwhitte

BP's Corexit Increases Uptake of Endocrine Disruptors in Fish - What Will It Do to Peop... - 0 views

firedoglake.com/...fish-what-will-it-do-to-people

PAH oil toxicity Corexit dispersant

shared by suwhitte on 25 May 10 - Cached
  • suwhitte on 25 May 10
     
    Report by an M.D. describing the ED effects of the dispersant used to "manage" the BP oil spill. Includes link to article on how PAH uptake by fish is increased when exposed to the dispersant (Corexit - give me a break on the name!).
Liz Richardson

Crude Oil Toxicity - 1 views

www.sciencecorps.org/crudeoilhazards.htm

oil toxicity PAH

shared by Liz Richardson on 24 May 10 - Cached
  • Liz Richardson on 24 May 10
     
    For Charlotte: EEDs do not have to be hormone based, they can just influence the natural functions of hormones. This site is recently developed to help people understand the effects of the BP Oil spill in the Gulf. I hope it is informative.
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
Anna McLean

Reproductive Toxins and Alligator Abnormalities at Lake Apopka, Florida - 0 views

ehp.niehs.nih.gov/...semenza-full.html

shared by Anna McLean on 24 May 10 - Cached
  • it has been shown that many of the environmental chemicals found in alligator plasma or eggs bind the alligator estrogen and/or progesterone receptors in vitro
  • Guillette et al. ( 1 ) suggested that the reproductive failure at Lake Apopka could have been related to general agricultural pollution and to a spill from a nearby pesticide manufacturing facility. From 1957 to 1981, the facility (Tower Chemical Co.) manufactured and stored both chlorinated and organophosphate insecticides as well as a copper-salt-based fungicide at a site 1.5 miles from Lake Apopka. Wastewater from the manufacturing process was discharged into an unlined pond, and chemicals were burned or buried on site. During a heavy rain in 1980, the percolation pond overflowed and acidic wastewater discharged into a marsh that drains into Lake Apopka. DDT and other chemicals contaminated the lake during this extensive spill.
  • ecause of the endocrine-disruptive potential of DDT's degradation products DDE and DDD, they have been the prime suspects in the reproductive abnormalities of the alligators
  • ...4 more annotations...
  • The route of exposure for the alligators living in this environment might have occurred through both oral and dermal exposure
  • he testicular abnormalities in alligators from Lake Apopka are similar to those in pesticide workers exposed to DBCP in that the seminiferous tubules are the affected target tissues.
    • Anna McLean
      Anna McLean on 24 May 10
       
      Similar abnormalities act as evidence for the negative effects of DBCP. Evidence such as this help to support the cause, and disable individuals from referring to the alligators' issues as coincidence. Or that they have nothing to do with chemical spills, pesticides, and other pollutants.
  • given the levels found in the remaining pond, it is almost certain that DBCP entered Lake Apopka during the 1980 spill.
  • The findings discussed above indicate a complex exposure scenario in which the etiology of the reproductive failure cannot be reconstructed with certainty due to the historic nature of the event
    • Anna McLean
      Anna McLean on 24 May 10
       
      Emphasizes the difficultly scientists have in proving the causes of the observed problems in many species, such as the Lake Apopka alligators.
Anna McLean

Human Health: Fish consumption -- Critical contaminants - 1 views

www.great-lakes.net/...critical.html

shared by Anna McLean on 24 May 10 - Cached
  • DDT and DDE are probable human carcinogens and endocrine disrupters.
  • Mercury is not known to be a carcinogen, but it is toxic to the fetuses of humans and animals.
  • ercury in Lake Huron fish has caused fish consumption advisories and has been detected in Lake Huron water, sediment and wildlife.
  • Anna McLean on 24 May 10
     
    Although the use of DDT was banned a long time ago, it is still negatively affecting wild life. This page adds more detail to what we saw in the film, "The Estrogen Effect: Assault on the Male."
  • Anna McLean on 24 May 10
     
    Under the metals section, there is a short description of heavy metals. These metals are known to damage organisms, and as shown in some of our mini-presentations, can act as EEDs. For example, erythropoietin's functions are inhibited by lead as an EED.
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
Liz Richardson

Global assessment of the state-of-the-science of endocrine disruptors - 0 views

www.who.int/...index.html

general EED wildlife humans

shared by Liz Richardson on 21 May 10 - Cached
  • Liz Richardson on 21 May 10
     
    This is just the index, but the WHO has attempted to pinpoint which hormone compounds are most effective EEDs, and which hormones are most often mimicked. Discusses EED effects on wildlife as well as humans. Criteria for assessment of endocrine disruptors proposed for future studies.
suwhitte

Environmental Contaminants Program Home Page, U.S. Fish and Wildlife Service - 2 views

www.fws.gov/...EndocrineDisruptors.cfm

wildlife EED general

shared by suwhitte on 20 May 10 - Cached
  • suwhitte on 20 May 10
     
    Effects of EEDs on wildlife. Website maintained by the US Fish and Wildlife Sevice. Also describes the Smart Disposal program.
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.
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.
suwhitte

DDT : An Introduction - 0 views

www.chem.duke.edu/...pest1.html

shared by suwhitte on 20 May 10 - Cached
  • suwhitte on 20 May 10
     
    A nice history of an ED that although banned since the early 70's is still with us along with its metabolites.
suwhitte

ATSDR Home - 0 views

www.atsdr.cdc.gov

shared by suwhitte on 20 May 10 - Cached
  • suwhitte on 20 May 10
     
    Registry for toxic substances including EEDs.
suwhitte

Why Chemicals Called Obesogens May Make You Fat - Newsweek.com - 0 views

www.newsweek.com/215179

EED obesogen

shared by suwhitte on 20 May 10 - Cached
  • suwhitte on 20 May 10
     
    Provides a basic description of obesogens and how they are thought to work. Good place to start.
suwhitte

Environmental Agents: Endocrine Disruptors - 0 views

www.niehs.nih.gov/...endocrine

EED general

shared by suwhitte on 16 May 10 - Cached
  • suwhitte on 16 May 10
     
    site maintained by the National Institute of Environmental Health Sciences.
suwhitte

Welcome to CDC's DES Update Homepage - 0 views

www.cdc.gov/des

ED transgen

shared by suwhitte on 16 May 10 - Cached
  • suwhitte on 16 May 10
     
    Background on diethylstilbesterol, a synthetic estrogen, that has caused transgenerational effects.
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."
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