the microcosm test can be assumed to be representative of the swimming inhibition
test of Daphnia magna, which is a single-species test regulated by the OECD.
Therefore, the utility of the microcosm test as a multiple-species culture system
that is a closer approximation of real ecosystems was made clear. After assessing the
impacts of landfill leachate from the oxygen demand that followed a 100-day oxygen
consumption principle of the landfill leachates, namely, the Ultimate BOD, the
NOEC for the 100-day oxygen consumption agreed with the m-NOEC. From this
finding, the effectiveness of the microcosm test was supported.
It is important to assess the complex influences of chemical agents, such as
surfactants and medicines, on the environment. To conduct such comprehensive
assessments, microcosm-WET tests should be used to examine drainage by
collecting total toxicity test data through single-species surveys of chemical contaminants in environmental water. It is thought that more details for high-risk
materials can be analyzed by the microcosm-WET test with a general comparison
analysis. Additionally, because the microcosm-WET test offers high precision at a
low cost, and it is expected that the correlation between the natural ecosystem and
the microcosm is high, the estimated NOEC is more realistic than that derived from
single-species tests, and the prediction of the behavior of the natural ecosystem is
more practically enabled. It can also be expected that wastewater management can
greatly contribute to the remediation of the environmental impacts of effluents by
introducing the microcosm-WET test of the Ministry of the Environment, Japan.
Literature Cited
Japan Sewage Works Association. Wastewater examination method -FY2012-. Tokyo; 2012.
Tatarazako N. The newest domestic and overseas trend of assessment and regulation of effluent
water using bioassay–overseas operation case to Japanese WET test introduction. Tokyo: NTS;
2014. 322pp.
9 Application to the Whole Effluent Toxicity Test
185
test of Daphnia magna, which is a single-species test regulated by the OECD.
Therefore, the utility of the microcosm test as a multiple-species culture system
that is a closer approximation of real ecosystems was made clear. After assessing the
impacts of landfill leachate from the oxygen demand that followed a 100-day oxygen
consumption principle of the landfill leachates, namely, the Ultimate BOD, the
NOEC for the 100-day oxygen consumption agreed with the m-NOEC. From this
finding, the effectiveness of the microcosm test was supported.
It is important to assess the complex influences of chemical agents, such as
surfactants and medicines, on the environment. To conduct such comprehensive
assessments, microcosm-WET tests should be used to examine drainage by
collecting total toxicity test data through single-species surveys of chemical contaminants in environmental water. It is thought that more details for high-risk
materials can be analyzed by the microcosm-WET test with a general comparison
analysis. Additionally, because the microcosm-WET test offers high precision at a
low cost, and it is expected that the correlation between the natural ecosystem and
the microcosm is high, the estimated NOEC is more realistic than that derived from
single-species tests, and the prediction of the behavior of the natural ecosystem is
more practically enabled. It can also be expected that wastewater management can
greatly contribute to the remediation of the environmental impacts of effluents by
introducing the microcosm-WET test of the Ministry of the Environment, Japan.
Literature Cited
Japan Sewage Works Association. Wastewater examination method -FY2012-. Tokyo; 2012.
Tatarazako N. The newest domestic and overseas trend of assessment and regulation of effluent
water using bioassay–overseas operation case to Japanese WET test introduction. Tokyo: NTS;
2014. 322pp.
9 Application to the Whole Effluent Toxicity Test
185