Before anyone reads too far into this, it should be clear that a study has shown evidence of this, but there is no undeniable proof!
Developmental pediatrician Dr. Tanya Froehlich and a team of colleagues analyzed data from 700 children aged 8-15, examining 3-PBA-levels and symptoms of ADHD. 3-PBA-levels are chemical indicators of exposure to pyrethroid pesticides. Pyrethroid pesticides are often thought to be the safest alternative, but this recent link begs further consideration.
Boys with detectable levels of 3-PBA were three times more likely to exhibit symptoms of ADHD. Similarly, for every 10-fold increase in 3-PBA levels, boys showed a 50% increased risk of exhibiting ADHD symptoms. The aforementioned link was not seen in girls.
Previous studies showed a link between pyrethroid pesticides and the dopamine system in mice. Dopamine levels, amongst other things, are linked with occurrence of ADHD.
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