RRC ID 4124
Author Lema SC, Schultz IR, Scholz NL, Incardona JP, Swanson P.
Title Neural defects and cardiac arrhythmia in fish larvae following embryonic exposure to 2,2',4,4'-tetrabromodiphenyl ether (PBDE 47).
Journal Aquat Toxicol
Abstract Polybrominated diphenyl ethers (PBDEs) are added to plastics, polyurethane foam, and textiles as a flame retardant. While PBDEs play a key role in reducing loss of human life and property from fires, these flame retardants have become pervasive organic contaminants in the environment and in the tissues of fish, birds, marine mammals, and humans. Levels of PBDEs in wildlife and humans continue to rise, raising concerns about potential ecological and health risks associated with exposure to these chemicals. Nevertheless, there is little currently known about the toxicological effects of PBDE exposure. Here, we examined the developmental toxicity of the PBDE congener 2,2',4,4'-tetrabromodiphenyl ether (PBDE 47) using the zebrafish (Danio rerio) as an ontogenetic model. Zebrafish embryos were exposed continuously to dissolved phase PBDE 47 (100-5000 microg/l) beginning 3-5 h post-fertilization (hpf). Fish treated with the highest concentrations of PBDE 47 delayed hatching, had reduced growth post-hatching, and displayed an abnormal dorsal curvature of the body with flexion at the hindbrain. By 96h post-fertilization larvae exposed to PBDE 47 had significant tachycardia, which progressed into atrioventricular block arrhythmias. Microinjection of fluorescent dye into the hindbrain ventricle revealed that cerebrospinal fluid in the neural tube and brain ventricles flowed more slowly in fish larvae exposed to PBDE 47, a likely etiology for the dorsal curvature. Similar, though much less pronounced, developmental toxicity also occurred in larvae exposed to PBDE 47 only for a 20h period during early embryogenesis (3-23 hpf), suggesting that PBDEs incorporated in lipid of the egg are bioavailable and cause toxicity later in life. Taken together, this work indicates that exposure to PBDE 47 can cause morphological abnormalities, impair cardiovascular function and cerebrospinal fluid flow, and provides a tractable starting point for using the zebrafish model to explore molecular mechanisms of PBDE toxicity.
Volume 82(4)
Pages 296-307
Published 2007-5-31
DOI 10.1016/j.aquatox.2007.03.002
PII S0166-445X(07)00095-1
PMID 17412433
MeSH Animals Central Nervous System / drug effects* Central Nervous System / growth & development Central Nervous System / physiopathology Cerebrospinal Fluid / drug effects Cerebrospinal Fluid / physiology Embryo, Nonmammalian / drug effects* Female Halogenated Diphenyl Ethers Heart / drug effects* Heart / growth & development Heart / physiopathology Hydrocarbons, Brominated / analysis Hydrocarbons, Brominated / toxicity* Larva / chemistry Larva / drug effects Male Phenyl Ethers / analysis Phenyl Ethers / toxicity* Survival Analysis Water Pollutants, Chemical / analysis Water Pollutants, Chemical / toxicity* Zebrafish / embryology Zebrafish / growth & development*
IF 4.346
Times Cited 151
Zebrafish NA