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Bisphenol A, chemical used to make plastic, lingers in body, study …

admin — Sat, 24 Jan 2009 13:57:39 +0000

A study being released today finds that bisphenol A, a chemical widely used to make plastic and suspected of causing cancer, stays in the body much longer than previously thought.
The findings are significant because the longer the chemical lingers in the body, the greater chance it has of doing harm, scientists say.
Researchers from the University of Rochester in New York also say the chemical may get into the body from sources such as plastic water pipes or dust from carbonless paper and not only from food containers that leach the chemical when heated.
The study results, published in Environmental Health Perspectives, have sparked a flurry of concern and renewed calls for regulation.
The study reinforces the urgent need for stricter government oversight and regulation of this extremely toxic chemical, said Janet Nudelman, director of program and policy at the Breast Cancer Fund, a health advocacy group. It adds to what we already know about BPA, a chemical so powerful that at extremely low levels parts per billion or even parts per trillion it can cross the placenta and alter the mammary gland of the developing fetus, increasing breast cancer risk later in life.
BPA, used to make baby bottles, dental sealants, food storage containers and thousands of other household products, was found in 93% of Americans tested.
The new study, conducted by Richard Stahlhut at the University of Rochester, used data on humans collected by the U.S. Centers for Disease Control and Prevention. Researchers looked at urine samples of 1,469 U.S. adults. They compared the levels of BPA based on how long the subjects had fasted.
The American Chemistry Council, which represents makers of BPA, maintains that the chemical is safe for all uses. Steven Hentges, spokesman for the trade group, dismissed the study as inherently limited.
The authors conclusions are, at best, speculation, Hentges said. Low levels of BPA found in the data are not a risk to human health.
BPA has been linked to spikes in breast cancer, diabetes and heart disease, even at very low levels. It has also been found to interfere with chemotherapy in breast cancer patients.
The Milwaukee Journal Sentinel had 10 household products tested and found toxic levels of BPA leaching from all of them.
Canada declared BPA to be a toxin and banned its use in baby bottles last year. In the United States, 14 states are considering similar action.
Federal regulators have been divided on the issue.
A group of scientists from the National Toxicology Program expressed some concern last year about the chemical for infants and children. But the Food and Drug Administration has said BPA is safe for all use.
The newspaper found federal regulators favored industry-financed studies in their assessments. Entire sections of the FDAs assessment contained identical language to reports written on behalf of chemical-makers or others with a financial stake in BPA.
The FDA safety assessment relied on two studies, both paid for by chemical-makers, and ignored hundreds of independent studies that found the chemical to cause harm in laboratory animals.
The FDAs own science advisory board has recommended that the FDA reconsider its ruling. FDA administrators have promised to study the matter further but so far have stood by their assessment.
Stahlhuts study is likely to reignite concerns about the chemicals safety.
This is bound to shake things up, Stahlhut said. It is saying that our risk assessments are wrong. Things we thought we knew arent necessarily so.
The research indicates for the first time that people are either constantly being bombarded with bisphenol A from non-food sources, such as receipts and plastic water piping, or they are storing the chemical in fat cells, unable to get rid of it as quickly as scientists have believed.
It provides evidence that we are being exposed to more BPA than we think and that contaminated food and beverages may not even be the main source of our BPA exposure, said Patricia Hunt, a professor at Washington State University who pioneered studies linking BPA to cancer. Scary, huh?
Scientists previously thought that BPA metabolized quickly, with half the concentration eliminated between four and six hours and all of it gone by 24 hours. Instead, Stahlhut, Shanna Swan, also of Rochester, and Wade Welshons of the University of Missouri-Columbia found that the levels dropped but then leveled off after eight hours and never disappeared.
They hang in there like a London fog, Stahlhut said.

Study adds to evidence of vaccine safety

admin — Tue, 13 Jan 2009 19:14:54 +0000

By CARLA K. JOHNSON –
CHICAGO (AP) — A new study from Italy adds to a mountain of evidence that a mercury-based preservative once used in many vaccines doesn’t hurt children, offering more reassurance to parents.
In the early 1990s, thousands of healthy Italian babies in a study of whooping cough vaccines got two different amounts of the preservative thimerosal (pronounced thih-MEHR’-uh-sawl) from all their routine shots.
Ten years later, 1,403 of those children took a battery of brain function tests. Researchers found small differences in only two of 24 measurements and those “might be attributable to chance,” they wrote in the February issue of the journal Pediatrics, which was released Monday.
Only one case of autism was found, and that was in the group that got the lower level of thimerosal.
Autism is a complex disorder featuring repetitive behaviors and poor social interaction and communication skills. Scientists generally believe genetics plays a role in causing the disorder; a theory that thimerosal is to blame has been repeatedly discounted in scientific studies.
“Put together with the evidence of all the other studies, this tells us there is no reason to worry about the effect of thimerosal in vaccines,” said the new study’s lead author, Dr. Alberto Tozzi of Bambino Gesu Hospital in Rome.
The debate over thimerosal and autism has been much stronger in the United States than in Italy, Tozzi said. But the researchers recognized a chance to examine the issue by going back to the children who had taken part in the 1990s whooping cough research.
Randomization sets the new study apart. The random assignment of children rules out the chance that factors other than thimerosal, such as education or poverty, caused the results.
Thimerosal, used in some vaccines to prevent the growth of bacteria and fungus, hasn’t been in U.S. childhood vaccines since 2001, except for certain flu shots. Italy and other European nations began removing it in 1999. U.S. health officials recommended the removal of thimerosal as a precaution and to reduce the overall exposure of children to mercury.
Safety regulations still require multi-dose vials of vaccines to contain some type of preservative to prevent the spread of infection from contaminated vials.
The study, funded by the U.S. Centers for Disease Control and Prevention, drew praise from outside experts.
“It’s yet another well done, peer-reviewed research study that has demonstrated there is no risk of any neurodevelopmental outcomes associated with thimerosal in vaccines,” said epidemiologist Jennifer Pinto-Martin of the University of Pennsylvania.
“This becomes the fourth study to look for subtle signs of mercury toxicity and show the answer was ‘no,’” said Dr. Paul Offit, chief of infectious diseases at the Children’s Hospital of Philadelphia, the author of a book on autism research and the co-inventor of a rotavirus vaccine.
Tozzi said comparing children with no exposure to thimerosal could have improved the study. “However, if thimerosal were a cause of harm, it is likely that this effect would increase with the administered dose,” he said.
The children received either 62.5 micrograms or 137.5 micrograms of ethyl mercury from all their shots during their first year of life. Thimerosal breaks down as ethyl mercury in the body. Before the reduction of thimerosal in the United States, the maximum exposure for infants was 187.5 micrograms of ethyl mercury.
The researchers found the children in both groups scored, on average, in the normal range on 11 tests of memory, attention, motor skills and other brain functions.
Those 11 tests included 24 measured outcomes. Small, but statistical differences were found for only two of those areas, and only for girls. The girls with higher exposure scored worse on a finger-tapping test with their dominant hands, and on a vocabulary test in which they were asked to name common objects.
There was no difference in boys on those outcomes or others. Researchers also found no difference in tic disorders. And the one autism case found in the lower-intake group was likely a chance finding, Tozzi said.

ADHD drugs cause hallucinations in some kids, study says

admin — Mon, 12 Jan 2009 20:27:00 +0000

Doctors have known that some children and adolescents taking stimulant medications for attention deficit hyperactivity disorder experience psychiatric symptoms from the drugs, such as hallucinations, hearing voices, paranoia and mania. In 2007, the Food and Drug Administration ordered manufacturers of stimulant medications to add new warnings about psychiatric and cardiovascular side effects to package inserts. And patient medication guides are also required to explain the risks of ADHD drug treatments. At the time of the FDA order, experts estimated the risk of an adverse psychiatric event from medication use at about 1 in 1,000 children.
, however, estimates the incidence of psychotic symptoms at 1.48 per 100 person-years. (Person-years is defined as total years of treatment with a drug. For example, 100 people taking a drug one year is 100 person-years.) The statistic was based on data from 49 randomized, controlled trials of ADHD medications. In those same studies, no psychotic symptoms were reported in children who did not receive medication. Moreover, an analysis of spontaneous adverse-event reports to the FDA showed more than 800 reports of psychosis or mania. Psychotic symptoms were found with every ADHD drug tested.
Just under 8% of U.S. children, ages 4 to 17, have been diagnosed with ADHD, according to a survey conducted in 2003 by the Centers for Disease Control and Prevention. More than half of these children were taking a medication for the disorder. However, the research reported today shows that psychotic symptoms occurred even in children who were not considered at high risk for psychosis or mania, such as children who abuse drugs or have other mental illnesses. In more than 90% of the cases, the children had never experienced hallucinations or psychosis. In most cases, the hallucinations were visual and tactile and involved seeing or feeling bugs, worms or snakes. The symptoms typically disappeared after the children stopped taking ADHD medication.
It’s not clear just why some children experience psychotic reactions to the drugs or what causes the symptoms. However, doctors should explain to parents that any psychosis or mania that occurs during treatment could be from the drug itself, said the authors of the report. And, they add, their paper is fresh evidence regarding the limitations of short-term clinical trials. The clinical trials of stimulant drugs showed a much lower rate of psychotic symptoms, but it wasn’t until the medications were widely prescribed in a broad range of people that psychotic adverse events became prominent.

Study: Zoloft and Cipralex better than other drugs

admin — Fri, 09 Jan 2009 11:06:04 +0000

LONDON (AP) — Doctors have long assumed that most antidepressants are interchangeable. But according to a new study, Zoloft and Cipralex work slightly better than 10 other popular drugs, and should be psychiatrists’ first choice for patients with moderate to severe depression.
Previous research found few differences between antidepressants. A U.S. government study in 2006 concluded that patients with major depression did equally well on different drugs.
But in a paper published online Thursday in the Lancet medical journal, two antidepressants came out on top, though only marginally.
International doctors examined more than 100 previous studies on a dozen antidepressants, which included nearly 26,000 patients from 1991 to 2007.
They found that Zoloft, developed by Pfizer Inc., and Cipralex, developed by Forest Laboratories in the U.S. and Danish drugmaker H. Lundbeck A/S in Europe, were the best options when considering benefits, side effects, and cost. In contrast, Pfizer’s Edronax was the least effective.
All three drugs are now available generically.
The other drugs tested were Celexa, Cymbalta, Efexor, Ixel, Luvox, Prozac, Seroxat, Remeron, and Zyban.
“The bottom line is that there is a rational hierarchy when prescribing antidepressants,” said Dr. Andrea Cipriani, the study’s lead author, of the University of Verona in Italy.
The experts judged a drug to be successful if it reduced patients’ baseline depression scores on two standardized tests by at least half and if patients had not stopped taking it within two months.
Side effects for the various drugs include nausea, sleeplessness, and sexual dysfunction.
Cipriani said all the antidepressants were effective, and that the differences between them were not huge. “If a patient is taking a drug and doing well, he should not stop and switch drugs,” he said.
Irving Kirsch, a professor of psychology at Britain’s University of Hull, predicted the study would affect doctors more than patients.
“Doctors will probably prescribe (Zoloft and Cipralex) more often, but patients may not see a big difference between one drug versus another,” he said. Psychiatrists should consider other ways to help patients, like behavioral therapy, Kirsch said.
The study was paid for by the authors’ academic institutions in Britain, Greece, Italy, and Japan. Cipriani has not received any grants from pharmaceuticals. Several of his co-authors reported receiving funding from various makers of antidepressants.

UT Southwestern doctor's study finds little cost-containment in …

admin — Sat, 03 Jan 2009 13:37:58 +0000

10:27 PM CST on Friday, January 30, 2009
New research by a UT Southwestern Medical Center physician calls into Dr. Ethan Halm, chief of internal medicine at UT Southwestern, found Local insurers didn’t dispute Halm’s findings but said it would not be While working at Mount Sinai School of Medicine in New York last year, Halm said he chose patients undergoing that surgery because it’s common, “This is a procedure for whom the vast majority of care is appropriate .
In Halm’s opinion, insurance companies bare some blame in escalated “Trying to reduce costly but unnecessary care is the low-hanging fruit Halm said there is growing evidence that the federal government is John Goodman, president of the National Center for Policy Analysis, a “It’s incredibly hard for them to do so,” Goodman “The whole concept is the buyer of a product is going to tell the seller Goodman said true cost savings in health care must come from doctors and North Texas’ largest insurers supported their actions.
Dr. Allan Chernov, medical director for Blue Cross and Blue Shield of That’s because physicians, patients and legislators have strongly “Although some large companies, and consultants, often seem to expect Aetna health insurance spokeswoman Anjanette Coplin said the insurer As a way of containing costs, its Web site lists price ranges of common Dr. Sam Ho, executive vice president and chief medical officer of UnitedHealthcare does require patients to meet prequalification “We have to balance out the hassle factor to physicians and the cost to question whether health insurers are adequately performing one of their main functions: containing costs.
that private managed-care plans for Medicare do no better job of steering patients away from unnecessary surgeries than the traditional fee-for-service system, where the patient goes to any provider and the doctor or hospital bills Medicare directly.
practical to always implement the level of cost-saving scrutiny Halm’s report suggests.
Halm examined differences in care for 11,400 Medicare patients who received a carotid endarterectomy – a surgery to restore blood flow by removing fatty plaque from neck arteries – over a 10-year period.
costly and mostly an elective procedure. He said he also chose carotid endarterectomy because it’s a surgery for which managed care plans routinely require pre-certification to weed out patients who don’t need it.
and necessary; however, about 9 percent is being done unnecessarily,” said Halm, whose research was published in the December issue of the
health care costs for not using their resources, pre-approval protocols, and existing published guidelines to prevent overuse of unnecessary and costly procedures.
when trying to control the costs of health care,” he said.
wasting money in Medicare cases by paying managed care companies much more than fee-for-service plans with the hope of containing costs or improving quality.
Dallas-based think tank, has long felt managed care companies are ill-equipped to contain costs.
said.
and producer how to produce. Can you think of any other market that works that way?”
hospitals, not insurance companies.
Texas, the region’s largest insurer, said his company is not in the business of “micromanagement of every health care interaction.”
opposed such moves in the past, Chernov said.
care micromanagement from a conceptual standpoint, they generally don’t support it in the face of employee/consumer reaction,” he said.
focuses more on preventive and wellness strategies.
surgeries for all local hospitals and doctors in their network.
UnitedHealthcare, the largest Medicare HMO in North Texas, said there is little medical evidence to justify spending extra money to pre-approve patients for a carotid endarterectomy.
guidelines for other costly procedures, such as back surgery and knee replacement surgery, he said.
manage this program,” Ho said.

Study Of Mother's Diet To Discover How It May Impact On Child's Health

admin — Fri, 02 Jan 2009 19:29:51 +0000

Could our mother’s diet at the time we are conceived set the course for our future health? This intriguing question is at the heart of a new study based on an “experiment of nature” being conducted by Wellcome Trust-funded researchers. We inherit our DNA – the genetic blueprint that determines our make-up – from our parents: 50% of our DNA from our mothers and 50% from our fathers.
CBSNews.com
FOXNews.com

Clean Air Means Longer Life, Study Says

admin — Fri, 02 Jan 2009 17:00:22 +0000

If the air in your city is clean, you can tack on about five months to your life. So suggests a new study by researchers at Brigham Young University and Harvard School of Public Health.
This study found that the average life expectancy in 51 cities in the United States increased by nearly three years in recent decades and that approximately five months of that increase came as a result of cleaner air.
“Life expectancy is a well-understood indicator for public health,” said C. Arden Pope III, a Brigham Young University epidemiologist and lead author on the study in the Jan. 22 issue of the New England Journal of Medicine. “We find that we are getting a substantial return on our investments in improving our air quality.”
Pope is no stranger to this issue. He and co-author Douglas Dockery, chair of the Department of Environmental Health at Harvard School of Public Health, teamed up with other researchers on important studies in the 1990s that revealed the negative health effects of infinitesimally small particles of pollution.
So small are these particles, known as “PM2.5,” that you would have to line up 25 of them end to end to span the width of a human hair. The danger of these tiny particles is that they can find their way deep into the respiratory system when inhaled.
Dr. Joel Schwartz, an environmental epidemiologist at the Harvard School of Public Health, agreed that the research “suggests that there is a phenomenon in the United States regarding increase in air pollution and shortened life span that is greater than the six locations studied in [previous research].”
Time for Tighter Standards?
The U.S. Environmental Protection Agency tightened air pollution standards in 1997 based on earlier data. But the new research suggests that it may be time to tighten these standards even further.
“This is a compelling paper,” said Dr. David Peden, chief of pediatric immunology at the University of North Carolina at Chapel Hill. “The results speak to the need for better standards from the U.S. Environmental Protection Agency.”

Bisphenol A, chemical used to make plastic, lingers in body, study …

admin — Thu, 25 Dec 2008 12:02:13 +0000

MILWAUKEE A study being released today finds that bisphenol A, a chemical widely used to make plastic and suspected of causing cancer, stays in the body much longer than previously thought.
The findings are significant because the longer the chemical lingers in the body, the greater chance it has of doing harm, scientists say.
Researchers from the University of Rochester in New York also say the chemical may get into the body from sources such as plastic water pipes or dust from carbonless paper and not only from food containers that leach the chemical when heated.
The study results, published in Environmental Health Perspectives, have sparked a flurry of concern and renewed calls for regulation.
The study reinforces the urgent need for stricter government oversight and regulation of this extremely toxic chemical, said Janet Nudelman, director of program and policy at the Breast Cancer Fund, a health advocacy group. It adds to what we already know about BPA, a chemical so powerful that at extremely low levels parts per billion or even parts per trillion it can cross the placenta and alter the mammary gland of the developing fetus, increasing breast cancer risk later in life.
BPA, used to make baby bottles, dental sealants, food storage containers and thousands of other household products, was found in 93% of Americans tested.
The new study, conducted by Richard Stahlhut at the University of Rochester, used data on humans collected by the U.S. Centers for Disease Control and Prevention. Researchers looked at urine samples of 1,469 U.S. adults. They compared the levels of BPA based on how long the subjects had fasted.
The American Chemistry Council, which represents makers of BPA, maintains that the chemical is safe for all uses. Steven Hentges, spokesman for the trade group, dismissed the study as inherently limited.
The authors conclusions are, at best, speculation, Hentges said. Low levels of BPA found in the data are not a risk to human health.
BPA has been linked to spikes in breast cancer, diabetes and heart disease, even at very low levels. It has also been found to interfere with chemotherapy in breast cancer patients.
The Milwaukee Journal Sentinel had 10 household products tested and found toxic levels of BPA leaching from all of them.
Canada declared BPA to be a toxin and banned its use in baby bottles last year. In the United States, 14 states are considering similar action.
Federal regulators have been divided on the issue.
A group of scientists from the National Toxicology Program expressed some concern last year about the chemical for infants and children. But the Food and Drug Administration has said BPA is safe for all use.
The newspaper found federal regulators favored industry-financed studies in their assessments. Entire sections of the FDAs assessment contained identical language to reports written on behalf of chemical-makers or others with a financial stake in BPA.
The FDA safety assessment relied on two studies, both paid for by chemical-makers, and ignored hundreds of independent studies that found the chemical to cause harm in laboratory animals.
The FDAs own science advisory board has recommended that the FDA reconsider its ruling. FDA administrators have promised to study the matter further but so far have stood by their assessment.
Stahlhuts study is likely to reignite concerns about the chemicals safety.
This is bound to shake things up, Stahlhut said. It is saying that our risk assessments are wrong. Things we thought we knew arent necessarily so.
The research indicates for the first time that people are either constantly being bombarded with bisphenol A from non-food sources, such as receipts and plastic water piping, or they are storing the chemical in fat cells, unable to get rid of it as quickly as scientists have believed.
It provides evidence that we are being exposed to more BPA than we think and that contaminated food and beverages may not even be the main source of our BPA exposure, said Patricia Hunt, a professor at Washington State University who pioneered studies linking BPA to cancer. Scary, huh?
Scientists previously thought that BPA metabolized quickly, with half the concentration eliminated between four and six hours and all of it gone by 24 hours. Instead, Stahlhut, Shanna Swan, also of Rochester, and Wade Welshons of the University of Missouri-Columbia found that the levels dropped but then leveled off after eight hours and never disappeared.
They hang in there like a London fog, Stahlhut said.

Study Links Photosynthesis Genes to Marine Virus Fitness

admin — Sat, 20 Dec 2008 01:10:05 +0000

Newswise — A recent Northeastern University study has shown, for the first time, the effect of individual genes on the fitness of a marine species at the ecosystem level. Using his innovative computer simulation model, engineering professor Ferdi Hellweger found that eliminating photosynthesis genes from viruses that attack important marine photosynthetic bacterial organisms will negatively impact the fitness of these viruses, ultimately killing them.
The findings, published in the journal
, have led to a new interdisciplinary field called “systems bioecology.” Combining systems biology and ecology, systems bioecology uses computer simulation to better understand the role of individual genes at the ecosystem scale.
With his computer simulation model, Hellweger “knocked out” the photosynthesis genes of cyanophages (viruses that attack marine cyanobacteria species such as Synechococcus and Prochlorococcus) to compare the fitness-level of these viruses to those containing the genes. Simulating a ten-year time span, he found that viruses without the photosynthesis genes were dead while the ones with the genes present survive.
The findings demonstrate that the fitness of cyanophage viruses is positively affected by the presence of photosynthesis genes.
Synechococcus and Prochlorococcus are known to be the most abundant photosynthetic organisms on Earth and play a major role in our carbon and climate cycles and the ocean ecosystem. Thus, finding out what factors influence the fitness and destructive impact of marine viruses on these bacteria is crucial in order to better understand the ecosystem.
The innovative computer simulation model can be expanded and modified using different genes and applying it to different species of other marine bacteria.
“Most of the biological science that comes out today is at the molecular level, but our models have not reached that point,” said Hellweger. “Systems bioecology has the potential for becoming widely used and the ‘method of choice’ for simulation in the post-genomic era.”
Founded in 1898, Northeastern University is a private research university located in the heart of Boston. Northeastern is a leader in interdisciplinary research, urban engagement, and the integration of classroom learning with real-world experience. The university’s distinctive cooperative education program, where students alternate semesters of full-time study with semesters of paid work in fields relevant to their professional interests and major, is one of the largest and most innovative in the world. The University offers a comprehensive range of undergraduate and graduate programs leading to degrees through the doctorate in six undergraduate colleges, eight graduate schools, and two part-time divisions. For more information, please visit
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Half of teens discuss sex, drugs on MySpace, says study

admin — Mon, 15 Dec 2008 23:09:59 +0000

More than half of teenagers frequently discuss sex, drugs and violence on their MySpace social networking pages, according to a pair of studies released by Seattle Children’s Research Institute.
The studies were published in the January 2009 issue of Archives of Pediatric & Adolescent Medicine. They indicated that in 500 randomly chosen MySpace profiles of self-reported 18-year-old men and women, 54 percent contained high-risk behavior information; 41 percent referred to substance abuse; 24 percent referred to sexual behavior and 14 percent referred to violence.
The study also examined whether a physician’s online communication to these teens about substance and sex abuse would have a positive impact. The study identified 190 youths’ profiles that were described as “at-risk.” Those 190 profiles received an online communication from a “Dr. Meg,” the online profile of Dr. Megan Moreno, formerly a research fellow at Children’s and now assistant professor of adolescent medicine at the
, who provided information about the risky nature of online personal disclosures
Three months after receiving the email from “Dr. Meg,” 13 percent of the profiles decreased references to sex behaviors and 26 percent decreased their substance use references.
“We were happy to see that even a brief email intervention may be feasible and showed promise for influencing online behavior,” Moreno said in a statement.