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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.
Bacteria living in human intestines can change arsenic's chemistry, in some cases producing a more toxic form that is linked to cancer.
This is the first report of arsenic becoming more harmful as it passes through the human digestive track. The results parallel those found in animal studies and suggest that regulators may need to take into account the way exposures occur when determining the health risks associated with arsenic. 30 June 2010. More...
A mixture of two common substances often found in food – bisphenol A and the soy phytoestrogen genistein – caused more serious developmental problems in rat embryos than would be expected from either one alone.
While BPA and genistein each inhibited some aspects of the embryos' growth, the combined exposures caused more severe problems. Together, they caused malformations and defects in the rats' central nervous system, including the brain. 14 May 2010. More...
Two new studies show remarkably high levels of PBDE flame retardants in the bodies of California children.
PBDE body burden levels in two separate populations of California children were 10 to 1,000 times higher than European children, 2 to 10 times higher than other U.S. children and adults, and approached levels measured in occupationally-exposed adults. 3 May 2010. More...
Certain types of PCBs can affect the way a brain chemical responsible for halting signals sends its chemical messages from nerve to nerve, according to research conducted on frog egg cells
These results further tease apart PCBs' complex effects on brain chemicals and better explain how these interactions can result in abnormal brain function. 10 March 2010. More...
Dibutyl phthalate (DBP) rubbed onto mouse skin changed the chemistry of the rodents' immune system and made them more prone to developing contact allergies, reports a new study published in the scientific journal Immunology.
This is the first study to show how DBP modifies the mouse immune system to predispose it to developing a type of allergy known as contact hypersensitivity. The results support prior studies that have found a connection between phthalates and allergies. 4 March 2010. More...
As one class of flame retardants is phased out due to health concerns, new types – sometimes with widespread exposure and unknown effects – may be phased in.
A new study examining one type of potential replacement chemicals called organophosphorous flame retardants finds that men exposed through house dust had lower thyroid hormone levels and reduced sperm concentration. This is one of the first human studies to look at potential health effects of exposure to these types of flame retardants. 5 February 2010. More...
A new study in rats shows that persistent organic pollutants (POPs) – at levels found in farmed Atlantic salmon – cause insulin resistance and associated obesity and liver disease in the animals. The study is the first to show this experimentally.
Insulin resistance can lead to type 2 diabetes, which is becoming a global epidemic. The association between high levels of POPs in people and increased chance of developing diabetes has been known since 2006. Until now, scientists could not positively conclude that POPs influenced the onset of diabetes. 14 January 2010. More...
In a study of nerves from rat brains, scientists confirm that the effects of different environmental contaminants can add together.
The research adds to a growing body of evidence that estimates of risk should evaluate combinations of chemicals that are most likely to be encountered through environmental exposure. 1 December 2009. More...
Flourescing fish may offer a quick and easy way to test if specific chemicals – or complex mixtures found in the environment – will affect the thyroid gland and its normal hormonal functions.
With so many chemical contaminants in the environment, rapid screening tools that target specific physiological processes or tissues are increasingly valuable to regulators and researchers. 2 October 2009. More...
Levels of antibiotics measured in streams, lakes and well water near pharmaceutical factories in India are 100,000 to 1,000,000 times higher than levels measured in waters that receive sewage effluent in the US or China.
Much of the world's supply of supply of generic antibiotics are produced in the study area. 9 September 2009. More...
New experiments with combinations of contaminants shows that mixtures can cause harm even when the level of each chemical in the mixture would cause no effect by itself.
Because people are exposed to hundreds of chemicals at a time--or more--these results indicate that setting safety standards based on the action of individual chemicals will not be sufficient to protect human health. 1 September 2009. More...
A team of researchers report that some low concentrations of a commercial brominated flame retardant mix – which have no effect in laboratory rats – caused pregnancy failures when fed to female mink.
The low levels tested also skewed thyroid hormone levels in juvenile offspring that were exposed during development and weaning. The younger animals were more sensitive to the chemicals than the adult animals. 30 June 2009. More...
Exposure to commonly used agricultural pesticides may increase the risk of developing Parkinson’s disease, particularly among people who have certain gene types.
The degenerative nerve disease can develop when dopamine levels in the brain are lower than normal. Without pesticide exposures, susceptible gene variants alone were not sufficient to increase risk. The increased risk to Parkinson's required both susceptible genes and pesticide exposure. 14 May 2009. More...
A British study shows that wastewater released from sewage treatment plants has a bigger impact than prior research suggests on egg production – and the long-term reproductive health – of fish living in the treated water.
This study was unique in that it looked at real effluents with their mixtures of different types and amounts of hormones. The authors showed that common methods used to assess the level of hormonal disruption may underestimate true reproductive impairment caused by estrogenic compounds. 1 May 2009. More...
A recent study in Arizona of household air identified over 400 airborne chemicals ranging from pesticides to phthalates.
Pesticides, including diazinon, chlorpyrifos and DDT were found at surprisingly high levels, as were phthalates. 28 April 2009. More...
A recent study conducted in California’s Central Valley found that people who lived near fields sprayed with a combination of pesticides used on crops such as potatoes, dry beans and tomatoes had an increased risk of Parkinson’s disease.
These results add to the growing literature suggesting that exposure to multiple chemicals may be more harmful than exposure to individual chemicals and contribute to the debate of evaluating chemical safety one at a time rather than in combination. 27 April 2009. More...
Exposure to a commercial mix made up of common flame retardants led to thinner eggshells, fewer hatchings and less successful reproduction in captive American Kestrels.
The flame retardant chemicals may be contributing to declining numbers of this species in parts of North America. The new findings are similar to the well known effects that the now banned insecticide DDT had on predatory raptors during the middle decades of last century. 15 April 2009. More...
A salmon study reveals that certain pesticide mixtures are more toxic than the sum of their individual components would suggest.
The impact of pesticides on population declines may be more important than previously thought. 27 March 2009. More...
A chemical that makes electronics and other household products safe from fire disrupts behavior in mice, suggesting that the chemical alters brain development. The behavioral effects were seen at fairly low doses, were worse at the higher doses tested and grew stronger as the mice aged.
The findings indicate that very early life exposure to the chemical -- called deca-BDE -- has lasting effects on the brain. The chemical may affect behavior by interfering with a neurotransmitter -- a nervous system signaling molecule -- called acetylcholine. 19 March 2009. More...
Research using a powerful statistical model suggests that chemical mixes in wastewater feminize male fish.
Scientists in the United Kingdom report that more than one type of hormonally active chemical -- not just those that act like estrogen -- play a role in sex reversal of male fish. Anti-androgens also contribute. 2 March 2009. More...
Eating a mix of soy compounds may be a safer way than traditional hormone therapies to protect against age-related brain disease, finds a new study that tested the mixtures in rats.
That's what scientists from the University of Southern California report from experiments in which they tested the effects of a combination of natural estrogen-like compounds. The mixture protected aging rat brains against disease without causing some of the reproductive-side effects that accompany the use of hormone replacement therapy (HRT). 24 December 2008. More...
A mix of two pesticides had greater toxic effects on exposed salmon than would be expected from one separately, adding to concerns that health risks from pesticides are underestimated.
Almost all risk assessments are conducted one chemical at a time, even though wildlife and humans are always exposed to many chemicals at a time. 19 December 2008. More...
A new study from China indicates that reducing air pollution from coal-burning power plants may improve children's ability to learn.
Children living near a recently closed coal-burning power plant performed better in a neurological development test compared to children living in the area three years prior when the plant was still in operation. 25 September 2008. More...
Phthalate exposure is widespread in infants and use of baby care products appears to be contributing, according to an analysis of babies' urine.
Greater use of lotions, powders and shampoos were associated with higher phthalate levels. The associations were strongest in younger infants. Parents wanting to decrease phthalate exposures for their infants should reduce the use of baby products unless needed for medical purposes. 4 February 2008. More...
New experiments reveal that the synthetic estrogen used by women for birth control causes wide ranging health effects in minnows, but that the effects differed when the drug was tested alone compared with when it was mixed with wastewater effluent.
The estrogen caused feminization of male fish, and altered DNA integrity, immune cell number, and ability to breakdown pollutants. The study highlights the need for more research on the potential health effects of exposure to complex mixtures. 7 September 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...
Very low doses of bisphenol A increase the expression of genes in fetal mice responsible for directing production of hormone receptors in prostate tissue.
The effect is seen at concentrations observed in human serum. The effect helps explain why this exposure increases sensitivity to hormones throughout the life of mice exposed in the womb, as well as why BPA causes enlarged prostates in adulthood. 8 June 2007. More...
Indoor air escaping from homes and buildings is a significant source of the PCBs found in outside air, a new study reports.
Its findings support a growing body of evidence indicating that indoor air contributes more to outdoor PCB pollution than other known sources, such as soil. The findings indicate that removing remaining indoor sources of PCBs will be important for lowering PCB body burdens. 26 April 2007. More...
Exposure to a mixture of anti-androgenic chemicals during development leads to male reproductive abnormalities.
Cryptorchidism (undescended testicles), atypical sperm and sexual dysfunction were observed in rabbits exposed to DDT and vinclozolin. These outcomes are consistent with the hypothesis of testicular dysgenesis syndrome caused by exposures to endocrine disruptors during fetal development. Reproductive Toxicology 15 April 2007. More...
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