Chironomus tentans life-cycle test: Design and evaluation for use in assessing toxicity of contaminated sediments

Journal Article · Sun Jun 01 04:00:00 EDT 1997 · Environmental Toxicology and Chemistry

DOI:https://doi.org/10.1897/1551-5028(1997)016<1165:CTLCTD>2.3.CO;2· OSTI ID:514599

Benoit, D A; Sibley, P K; Ankley, G T ^[1]; Juenemann, J L ^[2]

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1. Environmental Protection Agency, Duluth, MN (United States)
2. Integrated Laboratory Services, Duluth, MN (United States)

The development and standardization of toxicity test methods for assessing toxicity of contaminated freshwater sediments has focused predominantly on short-term exposures and lethality. In many situations, however, toxicity is more likely to become manifest over long periods of time so there is need for standardized testing procedures by which sublethal sediment toxicity can be adequately assessed. In this study, the authors present and evaluate a new life cycle test, using the midge Chironomus tentans, which enables the assessment of sublethal toxicity of contaminated sediments. The test is initiated with newly hatched larvae and uses four effects-based endpoints to assess toxicity: survival, growth, emergence, and reproduction. Survival is determined at 20 d and at the end of the test by back-calculating through emergence data. Growth can be determined at 20 d, which corresponds to the 10-d endpoint in the 10-d C. tentans growth test initiated with 10-d-old larvae. From day 23 to the end of the test, emergence and reproduction are monitored daily. The number of eggs per female is determined for each egg mass, which is then incubated for 6 d to determine hatching success. Each treatment in the life cycle test is terminated separately after 7 consecutive days without emergence. The authors evaluated the life cycle test by following one generation of C. tentans in sediments collected from the upper Mississippi River. Survival of larvae exceeded 90% at 20 d. Of these larvae, between 60 and 70% successfully emerged; survivorship among pupae and adults exceeded 85%. Mean egg production ranged from 906 to 1,107 eggs per female. The test required 65 d to complete, including pretest preparation. These data show that the C. tentans life cycle test can be used to assess sublethal toxicity accurately in contaminated sediments and provides a suitable compliment to the standard C. tentans 10-d test.

• Sponsoring Organization: USDOE
• OSTI ID: 514599
• Journal Information: Environmental Toxicology and Chemistry, Journal Name: Environmental Toxicology and Chemistry Journal Issue: 6 Vol. 16; ISSN 0730-7268; ISSN ETOCDK
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
56 BIOLOGY AND MEDICINE
APPLIED STUDIES
AQUATIC ORGANISMS
BIOLOGICAL INDICATORS
FLIES
FRESH WATER
LIFE CYCLE
SEDIMENTS
TOXICITY
WATER POLLUTION