ABSTRACT
The potential toxicity of decabromodiphenyl ethane (DBDP-Ethane) was explored in 5 types of organisms residing in the water column and/or sediment, e.g. Oncorhynchus mykiss, Pseudokirchneriella subcapitata, Daphnia magna, Chironmus riparius, and Lumbriculus variegates. Fish, algae or Daphnia were unaffected by acute exposures to water accommodated fractions of 110mg DBDP-Ethane/L. Chronic exposure to DBDP-Ethane at the highest dose tested, 5000mg/kg dry sediment, did not affect midge mean development times, emergence or development rates or oligochaete survival, reproduction or dry weight. The chronic EC50, LOEC and NOEC were ≥5000mg/kg in the two sediment species. Applying an assessment factor of 50, the unbounded predicted no effect concentration (PNEC(sediment)) was 100mg/kg dry sediment. The calculated PNEC indicates DBDPE-Ethane presents little risk to sediment organisms. These results add to DBDP-Ethane's existing database in the terrestrial compartment and mammals.
Subject(s)
Bromobenzenes/toxicity , Water Pollutants, Chemical/toxicity , Animals , Chironomidae/drug effects , Chlorophyta/drug effects , Daphnia/drug effects , Daphnia/growth & development , Geologic Sediments/chemistry , Oligochaeta/drug effects , Oncorhynchus mykiss , Reproduction/drug effects , Risk AssessmentABSTRACT
Decabromodiphenyl ethane (DBDP-Ethane) was evaluated for its potential to effect sewage sludge respiration, soil nitrification, survival and reproduction in Eisenia fetida, and seedling emergence and growth in Zea mays, Lolium perenne, Glycine max, Allium cepa, Lycopersicon esculentum, and Cucumis sativa. The no observed effect concentrations (NOECs) were identified at the limit concentration level for sewage sludge respiration (>10 mg DBDP-Ethane/kg dry soil), >2500 mg/kg dry soil for soil nitrification, >3720 mg/kg dry soil for earthworm survival, and >6250 mg/kg dry soil for seedling emergence and growth in Z. mays, L. perenne, and G. max . Treatment-related effects were identified for E. fetida reproduction, C. sativa survival, and L. esculentum and A. cepa height and dry weight. The most sensitive endpoints were decreased height and dry weight for A. cepa and decreased reproduction for E. fetida with NOECs of 1563(nominal) (1540(measured)) and 2210(nominal) (1907(mean measured)) mg/kg dry soil. The NOEC for soil nitrification and the lowest NOEC identified for soil (i.e., A. cepa) were used to derive predicted no effect concentrations (PNEC) values of 2500 mg/kg for sewage sludge and 156 mg/kg for soil. The calculated PNECs indicate DBDP-Ethane presents little risk to organisms in the sewage sludge and soil compartments.
