title: Acute toxicity of heavy metals towards freshwater ciliated protists.
abstract: The acute toxicity of five heavy metals to four species of freshwater ciliates (Colpidium colpoda, Dexiotricha granulosa, Euplotes aediculatus, and Halteria grandinella) was examined in laboratory tests. After exposing the ciliates to soluble compound of cadmium, copper, chromium, lead, and nickel at several selected concentrations, the mortality rate was registered and the LC50 values (with 95% confidence intervals) were calculated. Large differences appeared in sensitivities of the four species to the metals. H. grandinella showed the highest sensitivity for cadmium (0.07 mg l(-1), LC50) and lead (0.12 mg l(-1), LC50), whilst E. aediculatus showed the highest sensitivity for nickel (0.03 mg l(-1), LC50). The comparison with data obtained with other species indicate that Halteria grandinella and Euplotes aediculatus are excellent and convenient bioindicator for evaluating the toxicity of waters and wastewaters polluted by heavy metals. The short time (24 h) and simplicity of the test procedure enable this test to be used in laboratory studies.
authors.affiliation: Dipartimento di Scienze Ambientali, Università degli Studi di Parma, Parco Area delle Scienze 11/A, 43100 Parma, Italy. paolo.madoni@unipr.it
authors.forename: Paolo
authors.initials: P
authors.lastname: Madoni
authors.forename: Maria Giuseppa
authors.initials: MG
authors.lastname: Romeo
mesh_terms: D000818:Animals; D002104:Cadmium / Q000633:toxicity; D002857:Chromium / Q000633:toxicity; D016798:Ciliophora / Q000187:drug effects*; D003300:Copper / Q000633:toxicity; D004781:Environmental Exposure; D004784:Environmental Monitoring / Q000379:methods; D005618:Fresh Water; D007854:Lead / Q000633:toxicity; D007928:Lethal Dose 50; D019216:Metals, Heavy / Q000633:toxicity*; D009532:Nickel / Q000633:toxicity; D023382:Toxicity Tests, Acute; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D019216:Metals, Heavy; D014874:Water Pollutants, Chemical; D002104:Cadmium; D002857:Chromium; D007854:Lead; D003300:Copper; D009532:Nickel