title: Bifenthrin inhibits neurite outgrowth in differentiating PC12 cells.
abstract: BACKGROUND
  Bifenthrin is a third generation member of the synthetic pyrethroid family of insecticides. As a new pesticide within a relatively new class of pesticides, bifenthrin is considered relatively safe. Here, we used the PC12 neuronal cell line to examine the effect of bifenthrin on the formation of neurites and the potential developmental neurotoxicity of this pesticide.
  
  
  METHODS
  PC12 cells were exposed to varying concentrations of technical grade bifenthrin or Ortho Home Defense. Cell viability was determined using the AlmarBlue Toxicity Assay. Nontoxic concentrations of these chemicals were concomitantly with nerve growth factor and neurite outgrowth was assessed.
  
  
  RESULTS
  Ortho Home Defense preparation reduced PC12 cell viability by approximately 50% and 70% at dilutions that correlate to bifenthrin concentrations of 10(-5) M and 10(-4) M, respectively. In contrast, technical grade bifenthrin, was not toxic to PC12 cells at 10(-3) M, which was the highest concentration tested that was soluble. At "nontoxic" concentrations of 10(-7) M and 10(-6) M, the Ortho Home Defense inhibited nerve growth factor-mediated neurite outgrowth by 30% and 55% respectively. Furthermore the nontoxic concentrations of technical grade bifenthrin of 10(-6) M and 10(-3) M inhibited neurite outgrowth by approximately 35% and 75% respectively.
  
  
  CONCLUSIONS
  These data suggest that the toxicity of the Ortho Home Defense preparation was due to the "inert" additives in the preparation and not the bifenthrin itself. Further, these data suggest that, even in the absence of overt toxicity, bifenthrin may have deleterious effects to developing nervous system.
authors.affiliation: Department of Biology, Adelphi University, One South Avenue, Garden City, NY 11530, USA.
authors.forename: Van
authors.initials: V
authors.lastname: Tran
authors.forename: Natalie
authors.initials: N
authors.lastname: Hoffman
authors.forename: Adaobi
authors.initials: A
authors.lastname: Mofunanaya
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Pryor
authors.forename: Olutosin
authors.initials: O
authors.lastname: Ojugbele
authors.forename: Ashlea
authors.initials: A
authors.lastname: McLaughlin
authors.forename: Lydia
authors.initials: L
authors.lastname: Gibson
authors.forename: Josephine A
authors.initials: JA
authors.lastname: Bonventre
authors.forename: Katherine
authors.initials: K
authors.lastname: Flynn
authors.forename: Benjamin S
authors.initials: BS
authors.lastname: Weeks
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D002470:Cell Survival / Q000187:drug effects; D007306:Insecticides / Q000633:toxicity*; D016501:Neurites / Q000187:drug effects* / Q000473:pathology*; D009498:Neurotoxins / Q000633:toxicity; D016716:PC12 Cells; D011722:Pyrethrins / Q000633:toxicity*; D051381:Rats
chemical_list: D007306:Insecticides; D009498:Neurotoxins; D011722:Pyrethrins; C099952:bifenthrin