An evaluation of aquatic toxicity data with a population growth model for application to environmental hazard assessment

Thesis/Dissertation · Wed May 01 04:00:00 EDT 1991

OSTI ID:10104658

Burton, W D

Acute and chronic bioassays with the cladocerans Ceriodaphnia dubia and Daphnia magna were conducted using four chemicals, each having a different mode of action. The chemicals were: cadmium (chloride), pentachlorophenol (PCP), 1-octanol, and 1-naphthyl-N-methylcarbamate (carbaryl). The data obtained from the tests were used to compare species sensitivities, endpoint sensitivities, and the relative toxicities of the chemicals. In the acute bioassays, estimates of the median lethal concentrations (48-h LC{sub 50}S) were used to compare the species sensitivities. Ceriodaphnia dubia was more sensitive than D. magna to all four chemicals, and carbaryl was the most toxic chemical to both species. The sensitivity of three endpoints (survival, reproduction and the intrinsic rate of natural increase, r) were used to evaluate the chronic toxicity of the four chemicals to C. dubia and D. magna. Survival, reproduction and r all declined with greater concentrations of the chemicals. These effects were evident in both the 7- or 14-d exposures. The lowest observed effect concentration (LOEC) determined from studies with the four chemicals showed that neither survival nor reproduction was consistently the more sensitive endpoint for either C. dubia or D. magna. The LOECs for r were the same for both exposure durations for each species. The data from this study demonstrate that the calculations of r from chronic toxicity data can provide equally sensitive bioassay results for protecting the environment, while eliminating conflicting interpretations of toxicant effects on separate endpoints. Furthermore, statistical decisions drawn from comparisons of the toxicity of exposure concentrations with the controls may not provide the most ecologically meaningful criteria for environmental protection. 103 refs., 16 figs., 15 tabs.

• Research Organization: Tennessee Univ., Knoxville, TN (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC05-76OR00033
• OSTI ID: 10104658
• Report Number(s): DOE/OR/00033--T461; ON: DE92004769
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540320
560300
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
AQUATIC ECOSYSTEMS
BIOASSAY
BIOLOGICAL MARKERS
BRANCHIOPODS
CADMIUM CHLORIDES
CARBAMATES
CHEMICALS METABOLISM AND TOXICOLOGY
CHEMICALS MONITORING AND TRANSPORT
CHLORINATED AROMATIC HYDROCARBONS
DATA ANALYSIS
LETHAL DOSES
MORTALITY
OCTANOLS
POLLUTANTS
POPULATION DYNAMICS
REPRODUCTION
RISK ASSESSMENT
STATISTICS
TOXICITY
WATER POLLUTION