Weight Loss drug linked to suicide and anxiety?

An Indiana scientist makes a rather provocative argument that exposure to pesticides in the womb can explain why Indiana babies conceived in July-August (Born March and April?) have lower achievement scores than the other kids.

ScienceDaily: Conception Date Affects Babys Future Academic Achievement

Dr. Winchester and colleagues linked the scores of the students in grades 3 through 10 who took the Indiana Statewide Testing for Educational Progress (ISTEP) examination with the month in which each student had been conceived. The researchers found that ISTEP scores for math and language were distinctly seasonal with the lowest scores received by children who had been conceived in June through August.

“The fetal brain begins developing soon after conception. The pesticides we use to control pests in fields and our homes and the nitrates we use to fertilize crops and even our lawns are at their highest level in the summer,” said Dr. Winchester, who also directs Newborn Intensive Care Services at St. Francis Hospital in Indianapolis.

“Exposure to pesticides and nitrates can alter the hormonal milieu of the pregnant mother and the developing fetal brain,” said Dr. Winchester. “While our findings do not represent absolute proof that pesticides and nitrates contribute to lower ISTEP scores, they strongly support such a hypothesis.”

Well, that is a bold leap of faith, and use of a correlation=causation argument that I don’t appreciate in most cases. Has this kind of work been done in other countries, or in urban environments without pesticide use?

I am sure that many chemicals have subtle, but significant effects on developing fetuses. And the chemicals the authors mention have links with hypothyroidism..

Nitrates and pesticides are known to cause maternal hypothyroidism and lower maternal thyroid in pregnancy is associated with lower cognitive scores in offspring.

There is a link, but without further data, I think the conclusions are a stretch. But, something to keep in mind I guess if you live in Indiana and want to plan a baby!

Disclaimer: I was conceived in June, and was in the upper echelons of achievement through school. So, by the power of personal experience, I am predisposed to scepticism. OTH, I grew up in a big city with consistently high pollution levels throughout the year and not much pesticide exposure.

Take that, Sharper Image, your air purifiers that you waste tons of paper sending me monthly catalogs for don’t work. The ones that use ozone react with organic compounds in the air, especially your fragrances in cleaning products, air fresheners and perfumes to make fine particles in that crucial 0.1-1 um size range that your lungs don’t clear very effectively.

Not a big deal in the grand scheme of things, especially with other indoor pollutants. But I always thought these air purifiers were a scam, I am glad somebody actually got the NSF to fund this study and get some proof!

Kinetic Analysis of Competition between Aerosol Particle Removal and Generation by Ionization Air Purifiers

Kinetic Analysis of Competition between Aerosol Particle Removal and Generation by Ionization Air Purifiers

Ahmad Alshawa, Ashley R. Russell, and Sergey A. Nizkorodov*

Department of Chemistry, University of California, Irvine, California 92697-2025

Abstract:

Ionization air purifiers are increasingly used to remove aerosol particles from indoor air. However, certain ionization air purifiers also emit ozone. Reactions between the emitted ozone and unsaturated volatile organic compounds (VOC) commonly found in indoor air produce additional respirable aerosol particles in the ultrafine (This model predicts that certain widely used ionization air purifiers may actually increase the mass concentration of fine and ultrafine particulates in the presence of common unsaturated VOC, such as limonene contained in many household cleaning products. This prediction is supported by an explicit observation of ultrafine particle nucleation events caused by the addition of D-limonene to a ventilated office room equipped with a common ionization air purifier.

That would have been my headline! It was a study of 29 women, and the results show a six-fold increase in the incidence of autism in children whose mothers were close to fields being sprayed with organochlorine pesticides. A factor of 6 is a big number, which is why they found statistical significance at such a low sample size.

Most organochlorine pesticides (the most famous being DDT) are already banned in the first world. The ones suspected here, endosulfan and dicofol are banned in quite a few countries including Belize, Singapore. Cambodia and Germany. The Stockholm convention (international treaty to identify and restrict the use of persistent organic pollutants) has identified endosulfan as a possible addition to its list of POPs.

Of course, the US has not even ratified the Stockholm convention thanks to the pesticide lobbies. So, nothing the Stockholm convention decides about endosulfan will  carry any legal weight. In this country, pesticides and most other chemicals in current use are “innocent until proven guilty”, meaning harm must be conclusively proven in a manner that will withstand court challenge. With industry sponsored research and lobbying, such a burden of proof is often insurmountable and therefore, hazardous pollutants are used in the US well beyond their sell-by dates.

Pesticide link to autism suspected – Los Angeles Times

Women who live near California farm fields sprayed with organochlorine pesticides may be more likely to give birth to children with autism, according to a study by state health officials to be published today. The rate of autism among the children of 29 women who lived near the fields was extremely high, suggesting that exposure to the insecticides in the womb might have played a role. The study is the first to report a link between pesticides and the neurological disorder, which affects one in every 150 children. But the state scientists cautioned that their finding is highly preliminary because of the small number of women and children involved and lack of evidence from other studies.

Clearly, the increase in autism incidence has many more factors linked to it than environmental chemical exposure, but this is interesting and good work. This study will doubtless be severely criticized by the pesticide lobby. After all, it’s only a correlation, no mechanism has been proposed, and the sample size is very small. But, as I mentioned before, you don’t normally see six-fold increases in disease incidences with ambient environmental exposure, so there is definitely something going on here.

Technorati Tags: autism, pesticides