Publications on ostracod toxicity tests ~カイミジンコ毒性試験の論文が出ました!~

カイミジンコHeterocypris incongruensの毒性試験に関する論文が2本、出版されました!

Our two papers on the toxicity test using an ostracod Heterocypris incongruens were published!

Niyommaneerat W, Nakajima F, Tobino T, Yamamoto K, 2017, Development of a chronic sediment toxicity test using the benthic ostracod Heterocypris incongruens and their application to toxicity assessments of urban road dust, Ecotoxicol Environ Safety, 143, 266-274. [DOI] ←LINK

Hiki K, Tobino T, Nakajima F, Tsukahara K, 2017, Duration of life-cycle toxicity tests with the ostracod, Heterocypris incongruens, Environmen Toxicol Chem, in press. [DOI] ←LINK




カイミジンコH. incongruensとは


Heterocyris incongruens is a crustacean species having bivalve-like shells. 


  ▲A picture of Heterocypris incongruens taken from a previous blog post.



H. incongruens has been used for the evaluation of environmental pollution such as sediment contamination. The test method was standardized by ISO (ISO 14371). 



The standardized test relies on 6-day mortality and growth inhibition. For the development of the ostracod toxicity test using other endpoints such as reproduction and long term mortality, we performed the following studies.



●1本目: Niyommaneerat et al., 2017, EESf:id:YamamotoLab:20170924093854p:plain

  ▲Word Cloud of Niyommaneerat et al. (2017) generated by   



This paper investigated the variability of reproductive parameters such as first day of brooding, life-time egg production, egg hatching ratio under non-toxic conditions. Then, the applicability of these endpoitns was discussed.



The developed chronic test was applied to test the toxicity of urban road dust.


●2本目: Hiki et al., 2017, ETC


  ▲Word Cloud of Hiki et al. (2017) generated by 



H. incongruensの卵は、100日以上も孵化しない場合があります。毎回の毒性試験でそれほど長い間孵化を観察するのは、とても面倒です…。そこでこの論文では、H. incongruensの孵化率・次世代個体数を指標とするときに孵化を何日間観察すれば良いのかを、個体群増加率の観点から議論しています。

H. incongruens sometimes produces long-dormant eggs (>150 days for hatching).t is desirable to shorten the duration of life-cycletoxicity tests including the observation period of egg development. This paper suggest a practical duration of life-cycle toxicity test with H. incongruens.



The experimental data of this paper relies on Mr. T's (an alumnus of our lab) bachelor's thesis.


K. Hiki