Importance of acclimation to environmentally relevant zinc concentrations on the sensitivity of Daphnia Magna toward zinc
Muyssen, B.T.A.; Janssen, C.R. (2005). Importance of acclimation to environmentally relevant zinc concentrations on the sensitivity of Daphnia Magna toward zinc. Environ. Toxicol. Chem. 24(4): 895-901. https://dx.doi.org/10.1897/04-112R.1 In: Environmental Toxicology and Chemistry. Setac Press: New York. ISSN 0730-7268; e-ISSN 1552-8618, more |  |
| Keywords | Chemical elements > Metals > Heavy metals
Chemical elements > Metals > Heavy metals > Zinc
Properties > Biological properties > Tolerance
Toxicology > Ecotoxicology
Arthropoda [WoRMS]; Branchiopoda [WoRMS]; Diplostraca [WoRMS]; Crustacea [WoRMS]; Daphnia magna Straus, 1820 [WoRMS]; Invertebrata
Fresh water |
| Abstract | Daphnia magna was acclimated for six generations to an acclimation range of 0.02 to 74 μg/L of Zn2+. This range was determined by combining physicochemical water characteristics of European surface waters with total Zn concentrations in these waters in such a way that they resulted in minimal and maximal free (i.e., assumed bioavailable) Zn ion activities. No significant differences were found in acute Zn tolerance between the different acclimation concentrations: Average 48-h median effective concentration (EC50) values ranged from 608 ± 94 to 713 ± 249 μg/L of Zn2+. Also, no significant shifts in chronic tolerance were observed: Average 21-d EC50 (based on net reproductive rate) ranged from 91 ± 20 to 124 ± 22 μ/L of Zn2+. However, at test concentrations less than the 21-d EC50, acclimation significantly increased the reproductive capacity of the offspring produced. This indicates that metal acclimation is not necessarily accompanied by an increase in tolerance but also may manifest in other responses (e.g., reproduction rate). Organisms acclimated to a range from 6 to 22 μg/L of Zn2+ produced significantly more offspring than organisms acclimated to lower and higher Zn concentrations in test concentrations up to 50 μg/L of Zn2+. This range corresponds to a previously established optimal concentration range for D. magna. Bioconcentration factors indicated that Zn was actively regulated in the acclimation range tested. |
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