Lethal concentration of methyl methanesulfonate in a new potential invertebrate model for ecotoxicology

Abstract Sensitivity to different concentrations (0-200 mgL-1) of the alkylating agent methyl methanesulfonate (MMS) was evaluated in the new potential invertebrate model, the amphipod Quadrivisio lutzi (Shoemaker, 1933) after 48 h of exposure in two separate bioassays. In the first bioassay (0, 50, 100 and 200 mgL-1 MMS), all amphipods at concentrations ≥ 50 mgL-1 MMS were dead before completing the 48 h of exposure, which was also observed in the second bioassay for concentrations ≥ 30 mgL-1 MMS. There was no significant effect of gender on average mortality. The median 48 h lethal concentration (LC50) was 23.6 mgL-1 MMS for Q. lutzi. Therefore, 1/3 or less of this concentration may be used for positive control in sublethal conditions. The high sensitivity of Q. lutzi to MMS is discussed in comparison to other invertebrates.