title: Acute toxicity assessment of camphor in biopesticides by using Daphnia magna and Danio rerio.
abstract: OBJECTIVE
  An ecofriendly alternative to chemical pesticides is bio-pesticides, which are derived from natural sources. The interest in bio-pesticides is based on the disadvantages associated with chemical pesticides.
  
  
  METHODS
  We conducted acute toxicity assessments of camphor, a major component of bio-pesticides, by using Daphnia magna (D. magna) as well as assessed the morphological abnormalities that occurred in Danio rerio (D. rerio) embryos.
  
  
  RESULTS
  The median effective concentration of camphor on D. magna after 48 hours was 395.0 μM, and the median lethal concentration on D. rerio embryos after 96 hours was 838.6 μM. The no observed effect concentration and predicted no effect concentration of camphor on D. magna, which was more sensitive than D. rerio, were calculated as 55.2 μM and 3.95 μM, respectively. Morphological abnormalities in D. rerio embryos exposed to camphor increased over time. Coagulation, delayed hatching, yolk sac edema, pericardial edema, and pigmentation of embryos mainly appeared between 24 and 48 hours. Further, symptoms of scoliosis and head edema occurred after 72 hours. In addition, bent tails, ocular defects and collapsed symptoms of fertilized embryonic tissue were observed after 96 hours.
  
  
  CONCLUSIONS
  The camphor toxicity results suggest that continuous observations on the ecosystem are necessary to monitor toxicity in areas where biological pesticides containing camphor are sprayed.
authors.affiliation: Bioenergy and Biomaterials, Interdisciplinary Program of Graduate School for Chonnam National University, Gwangju, Korea.
authors.forename: Eun-Chae
authors.initials: EC
authors.lastname: Yim
authors.affiliation: Department of Environmental and Energy Engineering, Chonnam National University, Gwangju, Korea.
authors.forename: Hyeon-Joe
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Department of Environmental and Energy Engineering, Chonnam National University, Gwangju, Korea.
authors.forename: Seong-Jun
authors.initials: SJ
authors.lastname: Kim
keywords: Acute toxicity; Bio-pesticides; Camphor; Danio rerio embryo; Daphnia magna; Morphological abnormalities