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While all links worked when entries were posted to the database, different publishers
have different policies about retaining articles and providing access to archived material.
Thus some of the links, particularly older ones, may no longer be functional.
For links no longer working, you may be able to gain paid access to text via the publisher's site.
When fed to fish, a common flame retardant affected thyroid-related gene actions and hormone levels that could alter metabolism, although the changes differed between the high and low doses tested.
Determining how these changes translate into health consequences for humans becomes a critical point since minnows and humans have similar thyroid hormone systems. In both, the thyroid gland, pituitary gland and hypothalamus work together to control many body functions, mainly metabolism. 2 February 2009. More...
Mice exposed to low levels of soy proteins before and shortly after birth were obese as adults and had reproductive changes that differed between the sexes.
The findings provide additional evidence that hormonally active compounds can act at low exposure levels and produce effects different from those caused by high exposures. 24 September 2008. More...
For the first time, scientists have demonstrated experimentally a strong effect of low doses of bisphenol A on monkeys, raising new concerns about possible effects on people.
After a month of continuous low-dose exposure, the ability of the monkeys brains to form key connections was eliminated. The study suggests that BPA exposure may be related to human brain disorders and diseases, such as Alzheimer's disease, schizophrenia and mood disorders. 10 September 2008. More...
In human fat tissues, bisphenol A suppresses levels of a key hormone, adiponectin, that protects people from heart attacks and Type II diabetes.
These results implicate BPA as a potential cause of metabolic syndrome, one of the most serious and costly public health problems in the US. 18 August 2008. More...
Minute quantities of a bacterial protein inserted in corn provoke immune reactions in mice.
The protein is added to increase the effectiveness of plant-based transgenic vaccines. The results indicate that special care will be needed with transgenic corn to reduce exposure to workers and the public if this protein is used commercially in corn or other food crops, to avoid unwanted immune responses in people and decreased effectiveness of oral vaccines that use the protein. 8 November 2007. More...
New data link low birth weight and body mass to very low levels of commonly used chemicals found in consumer products ranging from Teflon-coated cookware to water and stain repelling textiles.
Analyzing the relationship between vital statistics of newborns born at a city hospital in Baltimore, MD--measurements such as weight, length, and head circumference-- scientists found that babies with higher levels of perfluorinated compounds in their cord blood tended to be slightly but significantly smaller than those with lower exposure. 16 August 2007. More...
Exposure to a mixture of phthalates causes reproductive harm in an additive manner.
Rats exposed prenatally to a combination of DEHP and DBP had decreased testosterone levels and decreased expression of genes important for gonadal development. This research has important implications for humans who are continually exposed to low doses of a mixture of phthalates. Toxicological Sciences 8 July 2007. More...
Prenatal exposure to a mixture of anti-androgenic chemicals produces changes in the structure of and genes expressed in male reproductive organs.
Rats exposed to a mixture of vinclozolin, flutamide and procymidone had abnormal development of the prostate, seminal vesicles and epididymis. Exposure to low doses of each individual chemical did not cause these effects but exposure to a mixture of low doses did, indicating an additive effect. This research has important implications for similar conditions in humans, who are routinely exposed to mixtures of low doses of chemicals. Toxicological Sciences 1 July 2007. More...
The first study to examine the connection between human exposure to phthalates and changes in thyroid hormone levels reports that men with higher levels of the phthalate breakdown product MEHP in their urine had lower levels of two major thyroid hormones, T4 and T3 in their blood.
Changes in thyroid hormone levels can affect growth, development and metabolism and cause a number of human diseases. More research is needed to establish whether MEHP is causing the thyroid declines. 12 June 2007. More...
Cell experiments show that arsenic interacts at extremely low levels with several hormone receptors.
The dose-response curves contradict classic 'dose makes the poison' toxicology. The pattern of gene alteration at low doses is almost completely different than the pattern at high, overtly toxic doses. These results indicate the epidemiological links between low dose arsenic and a range of human health conditions, including cancer, diabetes, developmental problems and cardiovascular disease, may result from its ability to disrupt hormone mechanisms. Chemical Research in Toxicology. 4 January 2007. More...
The phthalate DEHP increases allergic reaction to a mite allergen in mice at levels within the range deemed safe by current EPA standards.
The dose-response relationship followed an inverted-U pattern, with an intermediate dose causing larger effects than the highest dose use. This is the first report of non-monotonic response for a phthalate. The results implicate DEHP as a possible causal agent in increasing prevalence of allergic reactions in developed countries. 18 October 2006. More...
At environmentally- relevant levels, the anti-bacterial agent triclosan interferes with thyroid control of metamorphosis in frogs.
This is the first demonstration of low-level impacts of triclosan on thyroid hormone function. Exposure to as little as 0.15 micrograms/L triclosan caused an earlier metamorphosis than normal, with effects on the tadpole brain and tail. The study raises new questions about human health risks from triclosan. Aquatic Toxicology. 15 October 2006. More...
Prenatal exposure to bisphenol A causes long-lasting changes in female rat breast tissue that increase the risk of cancer and also make the animals more sensitive to cancer-causing chemicals as adults.
The study strengthens support for a link between increasing rates of breast cancer in recent decades and increasing exposure to estrogenic chemicals like BPA. It also indicates that human epidemiological studies that fail to incorporate developmental exposures can't be trusted to identify cancer-causing agents. 25 September 2006. More...
Exposure to perchlorate can masculinize fish, causing some females to become hermaphrodites even at the lowest level tested.
These results indicate that perchlorate may pose reproductive risks. Doses used were within the range observed in the groundwater of 7 states but well above the EPA reference dose. Environmental Toxicology and Chemistry 1 August 2006. More...
Danish scientists conclude that for children, there is no safe level of exposure to exogenous steroids or endocrine disruptors.
Disrupted sex hormone action is believed to contributing to increasing incidence of testicular, breast and prostate cancers, as well as increased genital abnormalities in newborn boys and precocious puberty in girls. Human Reproduction Update. 27 July 2006. More...
Experiments with mice indicate that developmental exposure to dieldrin causes a persistent change in the dopamine system that makes the animal more at risk to Parkinson's-like changes later in life.
The early exposure causes a 'silent' state of dopamine dysfunction, so that subsequent exposures to chemicals causing Parkinson's have a greater effect in adulthood. Males are more affected than females, similar to human PD. FASEB. 8 July 2006. More...
Early life exposure to bisphenol A at environmentally-relevant levels causes neoplastic (cancerous) lesions in the prostates of adult rats, linking BPA to prostate cancer.
Animals exposed perinatally to BPA and estradiol develop prostate lesions in adulthood called high-grade PIN that are generally accepted as an early stage of prostate cancer in people. For BPA, the effect requires changes in adult hormone levels that mirror estrogen changes in ageing men. The effects are associated with failures in a key gene to undergo hypermethylation, following perinatal exposure. 4 June 2006. More...
New work by researchers at the Mount Sinai School of Medicine confirms that PCBs are endocrine disruptors capable of causing permanent alterations in the female reproductive tract.
Newborn mice exposed to environmentally relevant levels of Aroclor 1254, a commercial mix of PCBs, had decreased expression of a regulatory gene in the uterus. There were also changes in the structure of the uterus that persisted into adulthood. These changes were similar to those seen with low level DES exposure. Finally, this study showed there was a genetic predisposition, suggesting some mice are more sensitive to these exposures. Environmental Health Perspectives 1 June 2006. More...
For the first time at a national meeting of experts in endocrinology, the topic of endocrine disruption is discussed.
On June 3, 2005, The Endocrine Society held an unprecedented full-day forum on endocrine-disrupting chemicals (EDCs). There were 3 major themes were recurrent at the forum. First, the timing of exposure to endocrine disruptors is critical to the outcome of that exposure, with fetal or early postnatal exposure being particularly detrimental. Second, EDCs often act at environmentally relevant doses. Third, effects of EDCs not only impact the exposed individual but may also be transmitted to subsequent generations. Endocrinology 1 June 2006. More...
Science Byte: Experiments with mice reveal that exposure to environmentally-relevant levels of the phthalate DEHP caused atopic dermatitis-like skin lesions to get worse in mice.
The exposure level sufficient to cause adverse effects is comparable to recent estimates of the daily exposure of Americans and a thousand-fold lower than the no-effect level based on liver damage. The researchers propose that ubiquitous use of DHEP has contributed to widespread increases in immune diseases like atopic dermatitis. EHP. 27 May 2006. More...
Experiments with eel embryos indicate the collapse of Atlantic eel populations is likely to be the result of the acute sensitivity of eel embryos to PCB and dioxin contamination.
Most eels from European locations carry contaminant levels well within the range that, based on these experiments, would severly impair eel embryo survival. Damage seen in the embryos is typical for dioxin-induced impacts in a number of fish species. 12 March 2006. More...
Science Byte: A study of Latina women and their children found unexpectedly high variation in vulnerability to organophosphate pesticide impacts.
Some newborns were 26 to 50 times more susceptible than others, and 65 to 130 times more sensitive than some adults. The results indicate current standards may not be sufficiently protective. Pharmacogenetics & Genomics. 5 March 2006. More...
Growing evidence indicates endocrine disrupting chemicals not only interact with hormone receptors but also modulate the activity of steroidogenic enzymes.
This review summarizes the evidence for EDCs as modulators of steroidogenic enzymes, identifies the structure/activity relationship in terms of inhibiting specific enzyme activity, questions whether experimental observations can equate with natural in vivo exposure or dietary intake of EDCs, and finally looks at the mechanisms through which these chemicals may disrupt normal steroidogenesis. Baillière's best practice & research. Clinical endocrinology & metabolism. 1 March 2006. More...
Geographic differences in sperm quality may be due to differences in exposures to agricultural chemicals.
Fertile men from a rural area of Missouri were found to have poorer sperm quality than men from other more urban areas of the US. Men from Missouri were found to have elevated levels of the herbicides alachlor and atrazine, and the insecticide diazinon. International Journal of Andrology 1 February 2006. More...
An environmentally-relevant mixture of pesticides, each at 0.1 ppb, unexpectedly weakens tadpole immune function, resulting in fatal infections.
35% of animals exposed to the mixture died compared to 4% of those treated with pesticides one at a time. Of those that survived, 70% of the animals exposed to the mixture developed bacterial infections whereas none of the controls or animals exposed to one pesticide at a time showed similar symptoms. 24 January 2006. More...
A detailed analysis of the studies industry uses to defend bisphenol A reveals deep flaws and strong biases against finding adverse effects.
Not only is industry's own research flawed, but they have repeatedly chosen to ignore all but a handful of the studies on low level effects of bisphenol A that have been published in the peer-reviewed scientific literature. Most Americans are exposed to this contaminant at levels that cause effects in animals. 10 January 2006. More...
Science Byte: Adult survival was reduced in salamanders exposed to 4 parts per billion of atrazine when they were embryo and larvae.
The exposures used are well beneath those regularly found in habitats near sprayed fields. These results, along with studies demonstrating gonadal impacts in frogs, raise concerns about the role of atrazine in amphibian declines. 1 January 2006. More...
Science Byte: Prenatal exposure to lead during the third trimester has significant impacts on childhood intellectual development, with lasting and possibly permanent effects.
The study, carried out in Mexico City, found no evidence of a threshold. The steepest part of the dose-response curve was within the first few µg/dL of blood lead, indicating that much of the damage is already occurring at the lower levels of exposure. EHP. 30 December 2005. More...
Science Byte: A study of children in Hokkaido, Japan, finds an association between prenatal exposure to background levels of several dioxin isomers and impaired motor development.
In the study, peripheral blood of 134 pregnant women was analyzed for dioxins and PCBs. No association was seen with mental development. EHP. 21 December 2005. More...
Science Byte: The multi-causal origins of human disease and disability complicate applications of criteria commonly used to link cause with effect through epidemiological research.
Two of the 'Bradford Hill criteria' used by public health scientists--consistency and temporality--can be misleading when applied to endocrine disruption, because multiple causes can act upon the same endpoints, simultaneously or at different times. EHP. 10 November 2005. More...
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