Effects of chronic 2,4,6,-trinitrotoluene, 2,4-dinitrotoluene, and 2,6-dinitrotoluene exposure on developing bullfrog (Rana catesbeiana) tadpoles.
Chronic aqueous exposures were conducted using bullfrog (Rana catesbeiana) tadpoles (8 d old) exposed to TNT (0-4 mg/L), 2,4-DNT (0-4 mg/L), and 2,6-DNT (0-8 mg/L) for 90 d. Survival of tadpoles examined using Cox proportional hazard models was reduced at all concentrations tested. Percent of abnormal swimming and other morphological abnormalities after sublethal exposure to TNT, 2,4-DNT, and 2,6-DNT at 2 mg/L were also evaluated. The effects of TNT, 2,4-DNT, and 2,6-DNT on wet body mass, snout vent length (SVL), and developmental stage of surviving tadpoles were examined. Only 2,4-DNT did not have a significant effect on body mass or SVL, but all three compounds tested had significant effects on survival. Long-term continuous exposure to these compounds at concentrations of 0.25 mg/L could lead to significant changes in growth and survival of larval amphibians.
The Institute of Environmental and Human Health, Department of Environmental Toxicology, Texas Tech University, Reese Technology Center Building 555, 1207 Gilbert Drive, Lubbock, Texas 79416, USA. npaden@geiconsultants.com
Norka E
NE
Paden
Ernest E
EE
Smith
Jonathan D
JD
Maul
Ronald J
RJ
Kendall
D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D001835:Body Weight / Q000187:drug effects; D004136:Dinitrobenzenes / Q000633:toxicity*; D053834:Explosive Agents / Q000633:toxicity; D005260:Female; D007814:Larva / Q000187:drug effects / Q000254:growth & development; D008297:Male; D011892:Rana catesbeiana / Q000002:abnormalities / Q000254:growth & development*; D013550:Swimming; D014303:Trinitrotoluene / Q000633:toxicity*; D014874:Water Pollutants, Chemical / Q000633:toxicity*
D004136:Dinitrobenzenes; D053834:Explosive Agents; D014874:Water Pollutants, Chemical; D014303:Trinitrotoluene; C016403:2,4-dinitrotoluene; C023514:2,6-dinitrotoluene