Environmental Toxicology and Chemistry · 1986 · 43 citations · 8 references
Natural SciencesEnvironmental SciencesToxicologyAquatic ToxicologyEcotoxicologyEnvironmental ToxicologyAquatic EcotoxicologyFreshwater ToxicologyWater PollutionWater QualityAmmonium ToxicityAquatic Toxicity TestingChronic Aquatic ToxicityDaphnia Toxicity TestingNitrogen ToxicityWater Quality Standards
Abstract The acute and chronic toxicity of ammonia (expressed as un-ionized ammonia nitrogen, NH3-N) to Daphnia magna was determined in support of the development of site-specific water quality standards for ammonia in the Tittabawassee River at Midland, Michigan. The 48-h LC50 value (95% confidence interval) obtained was 2.94 (2.70 to 3.22) mg NH3-N/L. The 21-d chronic value, presented as the maximum acceptable toxicant concentration (MATC), was between 0.42 and 0.87 mg NH3-N/L. Expressing the chronic value as the geometric mean of 0.42 and 0.87 resulted in an MATC of 0.60 mg NH3-N/L. The toxicity values derived during this study were similar to those reported in the literature for D. magna.
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