[Stitcher]

Chemical Exposure Creating a "Silent Pandemic" of Neurodevelopmental Disorders?

By: Caroline Cassels
Lancet. Published online November 8, 2006

http://www.medscape.com/viewarticle/...4005&src=nldne

November 8, 2006 — An online review article published November 8 in the Lancet says environmental exposure to toxic chemicals in utero and in the early stages of life may be creating a "silent pandemic" of neurodevelopmental disorders.

In their paper, Philippe Grandjean, MD, from the University of Southern Denmark in Odense, Denmark, and Philip Landrigan, MD, from the Mount Sinai School of Medicine, in New York, call for new, stricter approaches to chemical testing and controls that recognize the "unique vulnerability of the developing brain."

In conducting their review, the authors used the US National Library of Medicine hazardous substances data bank, supplemented by fact sheets from the US Agency for Toxic Substances and Disease Registry, and the integrated risk information system of the US Environmental Protection Agency to identify industrial chemicals that have proven neurotoxic effects in humans.

"The combined evidence suggests that neurodevelopmental disorders caused by industrial chemicals have created a silent pandemic in modern society," they write.

Significant Impact

The article cites 5 industrial chemicals, including lead, methylmercury, and polychlorinated biphenyls (PCBs), solvents, and pesticides, that are recognized causes of neurodevelopmental disorders.

Exposure to these chemicals during early fetal development can cause brain injury at doses much lower than those affecting adults. Recognition of these risks has given rise to evidence-based programs of prevention, such as the elimination of lead additives in gasoline and house paint. While such initiatives have been effective, most have been initiated only after substantial delays, they point out.

Recent research into lead neurotoxicity has shown that even very low exposures cause large functional decrements in children. Similarly, low prenatal exposure to methylmercury has been shown to have a significant impact, with 1 New Zealand study demonstrating a 3-point decrement in IQ and changes in affect in babies born to women with mercury concentrations in hair of greater than 6 µg/g, they write.

Tip of the Toxic Iceberg

But these "proven" brain-damaging chemicals may just be the tip of a potentially huge neurotoxic iceberg, Drs. Grandjean and Landrigan write.

According to the authors, there are an additional 200 chemicals that are known to cause clinical neurotoxic effects in adults. In addition, despite an absence of systematic testing, many other chemicals have been shown to have neurotoxic effects in animals.

In 1981, 100,000 chemicals in the European Union were registered for commercial use. In the United States, 80,000 are currently registered, yet fewer than half of these substances have been subjected "to even token laboratory testing," they write.

"Nearly 3000 of these substances are produced in quantities of almost 500,000 kg every year, but for nearly half of these high-volume chemicals, no basic toxicity data are publicly available, and 80% have no information about developmental or pediatric toxicity," they write.

An expert committee from the US National Research Council concluded that 3% of developmental disabilities are the direct result of environmental exposure to such substances and that another 25% arise through interactions between environmental factors and individual genetic susceptibility.

However, these estimates, the authors note, were based on scarce information about neurotoxicity and therefore likely underestimate the true prevalence of chemically induced abnormalities.

Lowering the Bar

The absence of testing and the high level of proof required for chemical-control legislation are the main impediments to the prevention of developmental disorders caused by exposure to chemical pollutants, they write.

As a result, Drs. Grandjean and Landrigan are calling for new approaches to control chemical exposures to protect the most vulnerable. The bar on exposure limits for chemicals should be set at values that recognize the unique sensitivity of the developing fetus and young children and aim at protecting brain development, they assert.

This precautionary approach, which is now beginning to be used in the European Union, would mean that any early indication of a potential for a serious toxic effect, such as developmental neurotoxicity, should lead to strict regulation. Restrictions could then be relaxed if it is subsequently proven that the substance is less harmful than initially thought.

In the meantime, the authors say that practicing clinicians should counsel their patients, particularly pregnant women, about avoiding exposure to chemicals of unknown and untested neurotoxic potential.

Lancet. Published online November 8, 2006.

[lou_lou]

we are the poisoned generation!
toxic waste -toxic food - toxicity changes our RNA and DNA...

Pharma's Poisoned Generation

By Evelyn PringleA growing number of professionals in the health care field are reporting that a relationship exists between the epidemic in neurodevelopmental disorders of autism, attention deficit hyperactive disorder, and speech or language delay all across the country, and the use of thimerosal, the mercury-based preservative used in childhood vaccines.

Vaccines are the only medicines that Americans are mandated to receive as a condition for attendance in school and day care, and for some types of employment. Parents who receive federal assistance are also required to show proof that their children have been vaccinated.

While the mandate for which vaccines must be included on the vaccine schedule is a state mandate, it is the Centers for Disease Control and Prevention (CDC) and its Advisory Committee that make the recommendations to which the majority of states adhere when determining mandates. The current epidemic actually began in the late 1980s when a large number of new vaccines were added to the schedule.

The blame is at least partially attributable to the failure of government officials to keep track of the cumulative amounts of mercury as they added triple-dose-vaccines to the schedule and the amount of thimerosal was multiplied by three.

Each new vaccine contained 25 micrograms of mercury and according to Professor Lynn Adams, of Radford University, who specializes in autism, by 1999, a study determined that the average child received 33 doses of 10 different vaccines by the age 5.

Elected lawmakers first became aware of the problem in 1999, when the House Committee on Government Reform initiated an investigation into the dangers of mercury exposure. An alarm rang early about the exposure of children to thimerosal.

By October 25, 2000, Committee Chairman, Dan Burton (R-IN), was trying to get the substance out of vaccines as quickly as possible and sent a letter to the Department of Health and Human Services, asking the director to get the FDA to recall all vaccines with thimerosal.

http://www.scoop.co.nz/stories/HL0511/S00347.htm

http://www.909shot.com/ResourceCenter/fatal.htm

[lou_lou]

http://research.cals.cornell.edu/entity?home=6&id=16452

mercury is ubiquitous!

This study seeks to identify the effects that low level in utero and adult exposure to mercury has on the functioning of the immune system with a particular emphasis on immunomodulation leading to autoimmunity and autoimmune disease.

Issue
Mercury is a ubiquitous contaminant in our environment and represents a particular risk to the developing fetus since high levels of mercury concentrate in the cord blood. The developing immune system is exquisitely sensitive to mercury and at the present time, we do not know the consequences of this exposure, and its potential long term effects on the health of the adult.

Response
We are exposing mice in utero and as adults to levels of mercury common to human exposure levels and identifying the changes in immune repertoire and function that result as a consequence of this exposure. We ultimately seek to identify whether these changes lead to increased autoimmunity and autoimmune disease, as has been suggested anecdotally, or in altered responses to infectious agents, as well as the mechanisms that are involved.

Impact
No changes have occurred yet, but our goal is to ultimately identify environmental modulators of immune responses and the potential risks associated with exposure to them.

Funding Sources
Private (e.g., commodity groups, foundations, companies)
several grants are pending
Collaborators
SUNY Upstate Medical University, Departments of Microbiology & Immunology and Pathology, Syracuse, NY
University of Rochester School of Medicine, Department of Environmental Medicine,Rochester, NY
Key Personnel
Allen Silverstone, SUNY Upstate Medical University, Department of Microbiology & Immunology, Syracuse, New York
Michael McCabe, University of Rochester School of Medicine, Department of Environmental Medicine,Rochester, New York
Arthur Tatum, SUNY Upstate Medical University, Department of Pathology, Syracuse, New York

[lindylanka]

There is a growing implication of household chemicals in breast cancer - it is my belief that women in particular are exposed to a hazardous cocktail of chemicals on a daily basis, and that this will eventually be revealed to be not just carginogenic, but neurotoxic too. There seems to be no regulation or general understanding of the chemical makeup of these substances which can be ingested through the skin, stomach and airways - even when we are being mindful about how we use them. They are the current equivalent of household pesticides, which are now mostly not in favour, though they were once used enthusiastically by many millions of people. They could be one of the reasons that more affluent nations are showing rising numbers of neurological conditions.

Lindy