Comparison of the Qwiklite algal bioluminescence test with marine algal growth rate inhibition bioassays.
Although marine algal bioassays based on growth rate inhibition over 72-96 h have been widely used to assess the toxicity of contaminants in waters and sediments, changes in pH over the test duration can lead to changes in contaminant speciation and consequently an under- or over-estimation of toxicity. In addition, high cell densities are used in order to obtain a detectable response, further reducing the tests' environmental relevance in marine waters. There is a need for rapid acute tests with ecologically relevant test endpoints that may be used as surrogates for longer-term chronic tests. This study compares the sensitivity and reproducibility of a rapid marine dinoflagellate (Pyrocystis lunula) bioluminescence test (QwikLite) with standard algal growth rate bioassays (Nitzschia closterium and Entomoneis c.f. punctulata) using ammonia and several antifouling agents (tributyltin [TBT], copper, and diuron) as reference toxicants. QwikLite was of similar sensitivity to ammonia as standard algal growth rate tests, but was less sensitive to copper, diuron and TBT, with 24-h EC50 values of 10 +/- 1.1 mg N/L, 0.128 +/- 0.021 mg Cu/L, 19 +/- 13 mg diuron/L, and 0.226 +/- 0.028 mg TBT/L. Inter-test precision using different batches of P. lunula was generally acceptable. On the basis of NOEC values, QwikLite was more sensitive to copper and ammonia at 25 degrees C than at 21 degrees C. QwikLite shows promise as a rapid, inexpensive screening test for acute toxicity of contaminants in marine environments.
Centre for Environmental Contaminants Research, CSIRO Land and Water, Private Mail Bag 7, Bangor, NSW 2234, Australia. jenny.stauber@csiro.au
Jenny L
JL
Stauber
Monique T
MT
Binet
Vivien W W
VW
Bao
Jenny
J
Boge
Amy Q
AQ
Zhang
Kenneth M Y
KM
Leung
Merrin S
MS
Adams
D000641:Ammonia / Q000633:toxicity; D000818:Animals; D001681:Biological Assay / Q000379:methods*; D003300:Copper / Q000633:toxicity; D017377:Diatoms / Q000187:drug effects* / Q000254:growth & development; D004141:Dinoflagellida / Q000187:drug effects* / Q000254:growth & development; D004237:Diuron / Q000633:toxicity; D004784:Environmental Monitoring / Q000379:methods*; D008163:Luminescent Measurements; D015203:Reproducibility of Results; D014220:Trialkyltin Compounds / Q000633:toxicity; D014874:Water Pollutants, Chemical / Q000633:toxicity*
D014220:Trialkyltin Compounds; D014874:Water Pollutants, Chemical; C011559:tributyltin; D000641:Ammonia; D003300:Copper; D004237:Diuron