Choice of vehicle affects pyraclostrobin toxicity in mice.

Journal Article (Journal Article)

Pyraclostrobin is a strobilurin fungicide that inhibits mitochondrial complex III of fungal and mammalian cells. In toxicity studies that were used to estimate the safety factor, pyraclostrobin was added to animal feed or to aqueous vehicles. However, foods containing residues of pyraclostrobin and other strobilurin fungicides (azoxystrobin, trifloxystrobin, fluoxastrobin) are frequently prepared in vegetable oil prior to human consumption. The primary objective of this study was to determine if pyraclostrobin dissolved in an oil-based vehicle had adverse health outcomes in mice when compared to aqueous-based vehicles. We found that pyraclostrobin does not fully dissolve in aqueous methyl cellulose (MC) or carboxymethyl cellulose (CMC), two vehicles used in industry-sponsored toxicity studies, but does fully dissolve in corn oil. Moreover, C57BL/6 mice receiving pyraclostrobin in corn oil displayed adverse health outcomes, including loss of body weight, hypothermia and diarrhea at lower doses than when added to feed or to aqueous vehicles. Our data suggest that previous studies underestimated the true toxicity of pyraclostrobin in mammals. Additional toxicity tests using oil-based vehicles are recommended to verify current safety recommendations for strobilurin fungicides.

Full Text

Duke Authors

Cited Authors

  • Tuttle, AH; Salazar, G; Cooper, EM; Stapleton, HM; Zylka, MJ

Published Date

  • March 2019

Published In

Volume / Issue

  • 218 /

Start / End Page

  • 501 - 506

PubMed ID

  • 30497033

Pubmed Central ID

  • PMC6338344

Electronic International Standard Serial Number (EISSN)

  • 1879-1298

International Standard Serial Number (ISSN)

  • 0045-6535

Digital Object Identifier (DOI)

  • 10.1016/j.chemosphere.2018.11.126


  • eng