Toxicity assessment of typical polycyclic aromatic hydrocarbons to Daphnia magna and Hyalella azteca in water-only and sediment-water exposure systems.

While the equilibrium partitioning (EqP) method has been demonstrated to effectively predict the adverse effects of nonionic organic chemicals in sediment on benthic organisms by sediment toxicity tests, only a limited number of studies have been performed both in water-only and whole-sediment toxicity tests using the same species and verified the validity of EqP-based toxicity assessment. To further examine the validity of the EqP method for application in a wide range of hydrophobicity, we conducted sorption/desorption experiments and both water-only and sediment toxicity tests using a popular aquatic crustacean species, Daphnia magna (48 h), and benthic species Hyalella azteca (96 h) for six typical polycyclic aromatic hydrocarbons (PAHs) with three to five rings and an amine derivative: anthracene, phenanthrene, fluoranthene, pyrene, benzo[a]pyrene, dibenzo[a,h]anthracene, and 1-aminopyrene. The linear sorption coefficient was determined and ranged from 2.

The effect of using light emitting diodes and fluorescent lamps as different light sources in growth inhibition tests of green alga, diatom, and cyanobacteria.

Aquatic organisms have been used to investigate the safety of chemicals worldwide. One such assessment is an algal growth inhibition test. Algal growth inhibition tests are commonly performed using a growth chamber with fluorescent lamps as the lighting source, as test guidelines require continuous uniform fluorescent illumination.

Production of genome-edited Daphnia for heavy metal detection by fluorescence.

Aquatic heavy metal pollution is a growing concern. To facilitate heavy metal monitoring in water, we developed transgenic Daphnia that are highly sensitive to heavy metals and respond to them rapidly. Metallothionein A, which was a metal response gene, and its promoter region was obtained from Daphnia magna.