TY - JOUR
T1 - Effects of atrazine on metamorphosis, growth, and gonadal development in the green frog (Rana clamitans)
AU - Coady, Katherine K.
AU - Murphy, Margaret B.
AU - Villeneuve, Daniel L.
AU - Hecker, Markus
AU - Jones, Paul D.
AU - Carr, James A.
AU - Solomon, Keith R.
AU - Smith, Ernest E.
AU - Van Der Kraale, Glen
AU - Kendall, Ronald J.
AU - Giesy, John P.
N1 - Funding Information:
This research was conducted under the oversight of the Atrazine Endocrine Ecological Risk Assessment Panel, Ecorisk, Inc., Ferndale, WA, with a grant from Syngenta Crop Protection, Inc. Also, an NIEHS training grant was available to support this research project. The authors thank the Histology Laboratory at Michigan State University for sectioning and staining frog gonad specimens. We also thank C. Bens, A. Gentles, W. Goleman, A. Hosmer, R. Sielken, L. Holden, and S. Williamson.
PY - 2004/6/25
Y1 - 2004/6/25
N2 - Embryos of the green frog (Rana clamitans) were collected from the field and exposed to 1 of 6 water-borne treatments for 273 d (mid July 2001 to mid April 2002). The treatments were 0, 10, or 25 μg/L atrazine, 0.005% ethanol (EtOH), or 0.1 mg/L estradiol or dihydrotestosterone carried in 0.005% EtOH. Treatments were applied in a static renewal system with a 50% test solution replacement approximately every 3 d. Following the exposure period, tadpoles were reared in freshwater until metamorphosis or until study termination (at d 506). Time to initiate and complete metamorphosis, stage-specific mortality, length and weight at metamorphosis, and gross morphology and histology of the gonads were examined. At environmentally relevant concentrations, atrazine did not consistently affect growth or metamorphosis. Compared to controls, the length of the larval period was greater in tadpoles exposed to 10 μg/L atrazine. However, the length of the larval period was not markedly different between tadpoles in the control and 25 μg/L atrazine treatments. Neither gross gonadal morphology nor histopathology of the gonads in postmetamorphic frogs was significantly altered in response to atrazine exposure. This study provides evidence that environmentally relevant concentrations of atrazine do not adversely affect the growth or reproductive development of R. clamitans.
AB - Embryos of the green frog (Rana clamitans) were collected from the field and exposed to 1 of 6 water-borne treatments for 273 d (mid July 2001 to mid April 2002). The treatments were 0, 10, or 25 μg/L atrazine, 0.005% ethanol (EtOH), or 0.1 mg/L estradiol or dihydrotestosterone carried in 0.005% EtOH. Treatments were applied in a static renewal system with a 50% test solution replacement approximately every 3 d. Following the exposure period, tadpoles were reared in freshwater until metamorphosis or until study termination (at d 506). Time to initiate and complete metamorphosis, stage-specific mortality, length and weight at metamorphosis, and gross morphology and histology of the gonads were examined. At environmentally relevant concentrations, atrazine did not consistently affect growth or metamorphosis. Compared to controls, the length of the larval period was greater in tadpoles exposed to 10 μg/L atrazine. However, the length of the larval period was not markedly different between tadpoles in the control and 25 μg/L atrazine treatments. Neither gross gonadal morphology nor histopathology of the gonads in postmetamorphic frogs was significantly altered in response to atrazine exposure. This study provides evidence that environmentally relevant concentrations of atrazine do not adversely affect the growth or reproductive development of R. clamitans.
UR - http://www.scopus.com/inward/record.url?scp=2942534874&partnerID=8YFLogxK
U2 - 10.1080/15287390490443722
DO - 10.1080/15287390490443722
M3 - Article
C2 - 15205037
AN - SCOPUS:2942534874
SN - 1528-7394
VL - 67
SP - 941
EP - 957
JO - Journal of Toxicology and Environmental Health - Part A
JF - Journal of Toxicology and Environmental Health - Part A
IS - 12
ER -