Toxicity of aqueous and sediment-associated fluoride to freshwater organisms

• Published in: Environmental toxicology and chemistry Vol. 22; no. 1; pp. 161 - 166
• Main Authors: Metcalfe-Smith, Janice L., Holtze, Keith E., Sirota, Gary R., Reid, James J., de Solla, Shane R.
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Periodicals, Inc 01.01.2003; SETAC
• Subjects: Amphipoda; Animal, plant and microbial ecology; Animals; Applied ecology; Biological and medical sciences; Chironomidae; Chironomus tentans; Cladocera; Cyprinidae; Daphnia; Daphnia magna; Ecotoxicology, biological effects of pollution; Effects of pollution and side effects of pesticides on protozoa and invertebrates; Fluoride; Fluorides - toxicity; Fresh water environment; Freshwater; Fundamental and applied biological sciences. Psychology; Geologic Sediments - chemistry; Hexagenia limbata; Hyalella azteca; Insecta; Lethal Dose 50; organisms; Pimephales promelas; Sediment; Toxicity; Water Pollutants - toxicity; Canada; Chironomidae; Chironomus tentans; Growth; Toxicity; Insecta; Cladocera; Amphipoda; Crustacea; Freshwater environment; Pisces; Pimephales promelas; Branchiopoda; Ephemeroptera; Interspecific comparison; Mortality; Fluoride Toxicity Freshwater organisms Sediment; Fluorides; Toxicity test; Sediments; Vertebrata; Lethal dose 50; Hyalella azteca; Sensitivity resistance; Arthropoda; Concentration effect; Water pollution; Cyprinidae; Invertebrata; Diptera; Daphnia magna
• ISSN: 0730-7268; 1552-8618
• DOI: 10.1002/etc.5620220121

Inorganic fluorides were declared toxic under the Canadian Environmental Protection Act in 1993 based on their potential to cause long‐term harmful effects in aquatic and terrestrial ecosystems, but information on the toxicity of sediment‐associated fluoride to freshwater benthic organisms was considered incomplete. The purpose of this study was to determine the toxicity of aqueous and sediment‐associated fluoride to several species of freshwater organisms and to determine if toxic effects could be expected under environmentally realistic exposures. Toxicity of fluoride (as NaF) in short‐term (48–96‐h) lethality tests was greatest for the amphipod Hyalella azteca (median lethal concentration [LC50] = 14.6 mg F−/L), followed by the mayfly Hexagenia limbata (32.3), the midge Chironomus tentans (124.1), the fathead minnow Pimephales promelas (262.4), and the cladoceran Daphnia magna (282.8). Relative toxicity in long‐term (10–28‐d) growth and survival tests in spiked sediment was similar. Hyalella azteca was the most sensitive species for growth (25% inhibitory concentration [IC25] = 290.2 μg F−/g), followed by C. tentans (661.4), H. limbata (1,221.3), and P. promelas (>5,600); H. azteca was also the most sensitive species for survival (LC50 = 1,114.6 μg F−/g), followed by H. limbata (1,652.2) and P. promelas and C. tentans (>5,600 for both). Concentrations of fluoride measured in sediments near some industrial point sources exceed some of these toxicity thresholds. Fluoride is highly mobile in aquatic systems and could potentially reach toxic levels in the water column during dredging to remove fluoride‐contaminated sediment.