title: Contact and fumigant toxicity of Pinus densiflora needle hydrodistillate constituents and related compounds and efficacy of spray formulations containing the oil to Dermatophagoides farinae.
abstract: BACKGROUND
  The toxicity of red pine needle hydrodistillate (RPN-HD), 19 RPN-HD constituents and another 12 structurally related compounds and the control efficacy of four experimental spray formulations containing RPN-HD (0.5. 1, 2 and 3% sprays) to adult Dermatophagoides farinae were evaluated.
  
  
  RESULTS
  RPN-HD (24 h LC50 , 68.33 µg cm(-2) ) was toxic to mites. Menthol was the most toxic compound (12.69 µg cm(-2) ), and the toxicity of this compound and benzyl benzoate did not differ significantly. High toxicity was also produced by α-terpineol, bornyl acetate, geranyl acetate, thymol, linalyl acetate, terpinyl acetate, citral, linalool and camphor (18.79-36.51 µg cm(-2) ). These compounds were more toxic than either deet or dibutyl phthalate. In vapour-phase mortality tests, these compounds were consistently more toxic in closed versus open containers, indicating that their mode of delivery was largely a result of vapour action. RPN-HD 3% experimental spray provided 95% mortality against adult D. farinae, whereas permethrin (cis:trans, 25:75) 2.5 g L(-1) spray treatment resulted in 0% mortality.
  
  
  CONCLUSIONS
  In the light of global efforts to reduce the level of highly toxic synthetic acaricides in indoor environments, RPN-HD and the compounds described merit further study as potential biocides for the control of Dermatophagoides populations as fumigants with contact action.
authors.affiliation: WCU Biomodulation Major, Department of Agricultural Biotechnology, Seoul National University, Seoul, South Korea.
authors.forename: Ju-Hee
authors.initials: JH
authors.lastname: Lee
authors.forename: Jun-Ran
authors.initials: JR
authors.lastname: Kim
authors.forename: Young Ryull
authors.initials: YR
authors.lastname: Koh
authors.forename: Young-Joon
authors.initials: YJ
authors.lastname: Ahn
mesh_terms: D056810:Acaricides / Q000737:chemistry / Q000302:isolation & purification / Q000633:toxicity*; D000818:Animals; D040001:Dermatophagoides farinae / Q000187:drug effects*; D005260:Female; D005651:Fumigation; D007928:Lethal Dose 50; D008297:Male; D010572:Pest Control, Biological / Q000379:methods*; D028223:Pinus / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000633:toxicity*; D018515:Plant Leaves / Q000737:chemistry; D010938:Plant Oils / Q000737:chemistry / Q000302:isolation & purification / Q000633:toxicity*
chemical_list: D056810:Acaricides; D010936:Plant Extracts; D010938:Plant Oils