ISBN:
9789264090910
Language:
English
Pages:
Online-Ressource (29 p)
Series Statement:
OECD Guidelines for the Testing of Chemicals, Section 2
Parallel Title:
Parallelausg. Essai n 233 ; Essai de toxicité sur le cycle de vie des chironomes dans un système eau-sédiment chargé ou eau chargée-sédiment
Parallel Title:
Parallelausg. Essai n 233 : Essai de toxicité sur le cycle de vie des chironomes dans un système eau-sédiment chargé ou eau chargée-sédiment
Keywords:
Environment
Abstract:
This Guideline is designed to assess the effects of prolonged exposure of chemicals to the life-cycle of the sediment-dwelling freshwater dipteran Chironomus sp. First instar chironomid larvae are exposed to five concentrations of the test chemical in sediment-water systems. The test substance is spiked into the water or alternatively the sediment, and first instar larvae are subsequently introduced into test beakers in which the sediment and water concentrations have been stabilised. Chironomid emergence, time to emergence, and sex ratio of the fully emerged and alive midges are assessed. Emerged adults are transferred to breeding cages, to facilitate swarming, mating and oviposition. The number of egg ropes produced and their fertility are assessed. From these egg ropes, first instar larvae of the 2nd generation are obtained. These larvae are placed into freshly prepared test beakers (spiking procedure as for the 1st generation) to determine the viability of the 2nd generation through an assessment of their emergence, time to emergence and the sex ratio of the fully emerged and alive midges. All data are analysed either by a regression model to estimate the concentration that would cause X% reduction in the relevant endpoint, or by using hypothesis testing to determine a No Observed Effect Concentration (NOEC).
DOI:
10.1787/9789264090910-en
