Pediatric neurobehavioral diseases in Nevada counties with respect to perchlorate in drinking water: An ecological inquiry

Abstract

This ecological study of children in the exposure area did not find evidence of an increased risk of either ADHD or of autism caused by perchlorate contamination in the drinking water. Furthermore, no difference in overall fourth-grade school performance was observed. No evidence was found that children from the area with perchlorate in the drinking water (up to 24 microg/liter) had either an increase in pediatric neurobehavioral disease (ADHD and autism) or a decrease in fourth-grade academic performance. The limitations of this ecological study relate to diagnostic criteria and ascertainment of geographic and demographic differences and to data on individual residence and water consumption during pregnancy.

Autism: Transient in utero hypothyroxinemia related to maternal flavonoid ingestion during pregnancy and to other environmental antithyroid agents

“…Perchlorate interferes with iodide uptake at the sodium/iodide symporter reducing the amount of iodide available for production of thyroid hormones. Nonetheless, a study in Nevada failed to correlate perchlorate levels in drinking water with pediatric neurobehavioral disorders, including autism [71]. As mentioned below (Table 2), a long list of environmental agents could explain also the progressive decline in urinary iodine excretion in the USA.…”

Review on Fate, Toxicity, and Remediation of Perchlorate

“…Environmental exposure to perchlorate has no effect on the neonatal blood TSH levels (Li et al, 2000)-environmental exposure to perchlorate up to 15 mg/L showed no effect on neonatal TSH levels for the first month of life. Children from areas with perchlorate in drinking water (up to 24 mg/L) showed no evidence of increase in pediatric neurobehavioral disease or a decrease in fourth-grade academic performance (Chang et al, 2003).…”

Response to Brucker-Davis et al.

“…Similarly, a study from Chile (11) compared the thyroid status of newborns and of schoolchildren in three Chilean towns with perchlorate concentrations of 100-120 mg/L, 5-7 mg/L, and no detectable (,4 mg/L) perchlorate, respectively, and found no adverse effect associated with perchlorate exposure. Finally, recent findings on the possible association of perchlorate in the drinking water and the presence of attention-deficit hyperactivity disorder (ADHD) in Nevada revealed no increased prevalence of ADHD in populations exposed to perchlorate in the drinking water (12).…”