From the fields to inner city, pesticides affect children - PON1 arylesterase & autism

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From the fields to inner city, pesticides affect children.

<http://e360.yale.edu/feature/from_the_fields_to_inner_city_pesticides_affect_ch\

ildrens_iq/2404/>

New York City's low-income neighborhoods and California's Salinas

Valley could hardly be more different. But scientists have

discovered that children growing up in these communities share a

pre-natal exposure to pesticides that appears to be affecting

their ability to learn and succeed in school....

Organophosphates are well known neurotoxins --- some were

developed as nerve agents for use in chemical weapons --- and work

on insects by targeting the nervous system. They have been on the

market since after World War II, but their use increased in the

1960s and 1970s, when they were promoted as an environmentally

preferable, rapidly degrading alternative to more persistent

organochloride pesticides, such as DDT. By the 1990s,

organosphosphate pesticides were one of the world's most widely

used type of insecticides. Such pesticides include chlorpyrifos

--- used in household bug sprays, termite control, lawn care

products, domestic pet flea and tick collars, and commercial

agriculture --- and malathion, used to control mosquitoes, fruit

flies, and lice.

Roughly 33 million pounds of organophosphate pesticides were used

in the U.S. in 2007....

<http://epa.gov/oppfead1/cb/csb_page/updates/2011/sales-usage06-07.html>

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Yale Environment 360

links to studies in article:

http://pediatrics.aappublications.org/content/118/6/e1845.full

http://ehp03.niehs.nih.gov/article/info:doi/10.1289/ehp.1003185

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Paraoxonase gene variants are associated with autism in North America,

but not in Italy: possible regional specificity in gene-environment

interactions. <http://www.ncbi.nlm.nih.gov/pubmed/16027737>

D'Amelio M et al.

Mol Psychiatry. 2005 Nov;10(11):1006-16

Organophosphates (OPs) are routinely used as pesticides in agriculture

and as insecticides within the household.... Since household use of OPs

is far greater in the USA than in Italy... These results are consistent

with our model and provide further support for the hypothesis that

concurrent genetic vulnerability and environmental OP exposure may

possibly contribute to autism pathogenesis in a sizable subgroup of

North American individuals.

Decreased serum arylesterase activity in autism spectrum disorders.

<http://www.ncbi.nlm.nih.gov/pubmed/20488557>

Gaita L, Manzi B, Sacco R, Lintas C, Altieri L, Lombardi F, Pawlowski

TL, Redman M, Craig DW, Huentelman MJ, Ober-Reynolds S, Brautigam S,

Melmed R, CJ, Marsillach J, Camps J, Curatolo P, Persico AM.

Psychiatry Res. 2010 Dec 30;180(2-3):105-13.

The PON1 gene, previously found associated with autism spectrum

disorders (ASDs), encodes a serum protein responsible for the

detoxification of organophosphates (OPs) and able to exert several

enzymatic activities. PON1 arylesterase, but not diazoxonase activity,

was significantly decreased in 174 ASD patients compared to 175

first-degree relatives and 144 controls (P=2.65×10?¹^(6)). First degree

relatives displayed intermediate activities, closer to patient than to

control levels. Differences between patients, first-degree relatives and

controls were especially evident among 164 Italians compared to 329

Caucasian-Americans, because arylesterase activity was significantly

higher in Italian controls, compared to Caucasian-American controls

(P=2.84×10?¹^(6)). Arylesterase activity and PON protein concentrations

were not significantly correlated, supporting a functional inhibition of

arylesterase activity in ASD patients over quantitative changes in

protein amounts. Serum arylesterase activity, in combination with PON1

genotypes at two single nucleotide polymorphisms (SNPs) known to

influence protein amounts (rs705379: C-108T) and substrate specificity

(rs662: Q192R), was able to discriminate ASD patients from controls with

elevated sensitivity and specificity, depending on genotype and ethnic

group. Serum arylesterase activity and genotyping at these two SNPs

could thus represent an informative biochemical/genetic test, able to

aid clinicians in estimating autism risk in ethnic groups with higher

baseline arylesterase activity levels.

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Nonetheless, see

Produce groups protest 'Dirty Dozen' pesticide list

<http://www.washingtonpost.com/politics/produce-industry-presses-usda-on-pestici\

de-report/2011/05/05/AFxzgQ4G_story.html>