Marc Joseph Nutrition - Blog

A new review study to be published in an upcoming issue of The Lancet notes that there are over 200 industrial chemicals that may damage the human brain, yet most are neither examined for potential effects on the developing brain nor tightly regulated. With one out of every six children now affected by a developmental disorder, the stakes are high.

As one of the study’s authors notes: “We must make protection of the young brain a paramount goal of public health protection. You have only one chance to develop a brain.”

This article does a good job of summarizing the study’s important points:

Few chemicals are assessed for neurotoxicity in the developing brain:

The authors then examined the published literature on the only five substances on the list–lead, methylmercury, arsenic, PCBs and toluene–that had sufficient documentation of toxicity to the developing human brain in order to analyze how that toxicity had been first recognized and how it led to control of exposure…the number of chemicals that can cause neurotoxicity in laboratory animal tests exceeds 1,000

The toxicity issue is most critical for children:

A developing brain is much more susceptible to the toxic effects of chemicals than an adult brain. During development, the brain undergoes a highly complex series of processes at different stages. An interference–for example, from toxic substances–that disrupts those processes, can have permanent consequences. That vulnerability lasts from fetal development through infancy and childhood to adolescence. Research has shown that environmental toxicants, such as lead or mercury, at low levels of exposure can have subclinical effects–not clinically visible, but still important adverse effects, such as decreases in intelligence or changes in behavior.

The impact is significant, both in terms of people and dollars:

[Researchers] conclude that industrial chemicals are responsible for what they call a silent pandemic that has caused impaired brain development in millions of children worldwide. It is silent because the subclinical effects of individual toxic chemicals are not apparent in available health statistics. To point out the subclinical risk to large populations, the authors note that virtually all children born in industrialized countries between 1960 and 1980 were exposed to lead from petrol, which may have reduced IQ scores above 130 (considered superior intelligence) by more than half and increased the number of scores less than 70. Today, it’s estimated that the economic costs of lead poisoning in U.S. children are $43 billion annually; for methylmercury toxicity, $8.7 billion each year.

What can be done?

The study’s authors have four recommendations:

1. Document chemicals that have caused toxic effects on the nervous system in humans to facilitate targeted preventive action against releases of these chemicals;
2. Document human exposures to neurotoxic chemicals and identification of subgroups at risk due to residence, occupation, diet, and other factors;
3. Research the consequences of developmental exposures to neurotoxic chemicals to expand our understanding of the long-term consequences of such exposures; and
4. Screen for neurotoxicity of commonly used chemicals to identify those that may present a hazard to brain development.

But they mention that these actions are expensive and will likely not be taken soon.

In the meantime, there are steps that individuals can take to protect themselves and their own children, including:

• Drinking filtered water
• Avoiding produce that is high in pesticides
• Reducing the use of harmful cleaning products in the home
• Selecting safer personal care products
• Having your residence tested for lead if it was built prior to 1978, and having lead paint professionally sealed and/or replaced
• Avoiding mercury in fish, amalgams, and vaccines

And for people who suspect toxin exposure may be an issue for either themselves, their own children, or future planned children, there are also other actions that can be taken.

This entry was posted on Thursday, November 9th, 2006 at 8:47 pm and is filed under ADD/ADHD, Alzheimer's, Autism, Heavy Metal Toxicity, Parkinson's, Lead, Mercury, Other Toxins. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.