Species-specific responses of developing anurans to coal combustion wastes.
Field surveys and field experiments have previously documented adverse effects of solid byproducts from coal incineration (coal combustion wastes (CCW)) on larval amphibians inhabiting aquatic habitats. However, a definitive link between CCW-exposure and developmental abnormalities has not been established because no studies have addressed the direct effects of prolonged exposure to CCW on larval amphibian development under controlled laboratory conditions. In the laboratory we exposed green frog (Rana clamitans) and wood frog (Rana sylvatica) larvae to either clean sand or CCW-contaminated sediment to investigate the direct effects of CCW exposure on trace element accumulation, growth, developmental rate, malformations, survival, and metamorphic success. While both species accumulated significant (P < 0.05) concentrations of at least six trace elements (As, Cd, Fe, Se, Sr, and V), effects of exposure to CCW varied between species, with R. clamitans larvae experiencing more severe effects including a 26% reduction in survival and a 45% reduction in metamorphic success. Furthermore, exposure to CCW decreased growth and developmental rates among larvae of both species that successfully completed metamorphosis. Larval period duration was increased by 10 and 11%, and size at metamorphosis was decreased by 10 and 39% in R. clamitans and R. sylvatica exposed to CCW, respectively. Rates of malformations were </= 4%, and were not dependent on species or sediment treatment. Our results confirm the direct effects of CCW on aquatic amphibian larvae suggested by previous field studies, and indicate that considerable variation may exist in sensitivity among species exposed to CCW. These findings have important implications for the management of CCW since > 50 million t are discharged annually to surface impoundments in the US, which are often used by breeding amphibians.
Snodgrass
Joel W
JW
Department of Biological Sciences, Towson University, Maryland 21252, USA. jsnodgrass@towson.edu
Hopkins
William A
WA
Broughton
Jeffroy
J
Gwinn
Daniel
D
Baionno
Jennifer A
JA
Burger
Joanna
J
D000704:Analysis of Variance; D000818:Animals; D003031:Coal / Q000633:toxicity*; D005618:Fresh Water; D007220:Industrial Waste; D007814:Larva / Q000187:drug effects / Q000254:growth & development; D008675:Metamorphosis, Biological / Q000187:drug effects*; D011898:Ranidae / Q000254:growth & development*; D013045:Species Specificity; D036401:Toxicity Tests, Chronic; D014131:Trace Elements / Q000493:pharmacokinetics
D003031:Coal; D007220:Industrial Waste; D014131:Trace Elements