Umbra Pygmaea Research Articles

Use of Umbra pygmaea and Mytilus edulis to detect mutagens in the aquatic environment

Chemicals/CAS: aroclor, 12767-79-2; benzo[a]pyrene, 50-32-8; mesylic acid ethyl ester, 62-50-0; mesylic acid methyl ester, 66-27-3; triaziquone, 68-76-8

Induction of sister-chromatid exchanges in fish exposed to Rhine water

The induction was studied of sister-chromatid exchanges in gill and testis of fish exposed to Rhine water. The eastern mudminnow, Umbra pygmaea, was chosen because the usefulness of this species with a karyotype of 22 large chromosomes had been demonstrated in cytogenetic mutagenicity testing. Fish exposed to Rhine water for 3 and 11 days showed a 2-fold and 3-fold higher SCE rate resp., compared with fish exposed to ground water of drinking water quality. There was no difference in SCE rate between gill and testicular cells before and after exposure. GLC/MS analysis indicated that different classes of chemical compounds may be involved in the cytogenetic effects found in fish. The mudminnow has proved to be a useful fish species for biological monitoring of mutagens in polluted waters. The SCE test may be a suitable test system to prescreen their mutagenic potential.

Cytogenetic changes in fish exposed to water of the river Rhine

The induction of chromosome aberrations in fishes, exposed to Rhinewater, was investigated. The mudminnow, Umbra pygmaea, was chosen for this study, because of its ideal karyotype of 22 large chromosomes. Gill cells were used for chromosome studies. Fish, kept in Rhinewater for 11 days had chromosome breaks in approximately 30% of the metaphases studied. Control fish, exposed to a very good quality of untreated groundwater had breaks in about 8% of the metaphases. Several Rhinewater extracts were tested for their mutagenic potential in the Salmonella-microsome test. The fraction of aromatic compounds was found to be positive. This may indicate that one or more of the compounds present in this fraction were also responsible for the cytogenetic changes found in the fish.