Algal Tests

Increasing the simplicity and cost efficiency of algal tests has been an important research activity in recent years. [134,135] New tests procedures involve the apphcation of flow cytometry, microplate techniques, and immobilized algae [135-140]. 

The use of bioassays in environmental monitoring has not been developed in Chile [191]. In 1998 the Ministry of Agriculture started to set up a bioassay laboratory for evaluation of the presence of toxic substances in water for irrigation and animal consumption. This ministry is now in the process of implementation of EPA standardized crustacean and algal tests with Daphnia and Selenastrum capricomutum, respectively. There is no governmental wastewater bioassay monitoring. 

Cleuvers, M. and Ratte, H.T. (2002b) The importance of light intensity in algal tests with coloured... 

Lucivjanskd, V., Lucivjanska, M. and Cizek, V. (2000) Sensitivity comparison of the ISO Daphnia and algal test procedures with Toxkit microbiotests, in G. Persoone, C. Janssen and W.M. De Coen (eds.), New Microbiotests for Routine Toxicity Screening and Biomonitoring, Kluwer Academic/Plenum Publishers, New York, pp. 243-246. 

No. Location 22 Algal Test Luminescent Bacteria Test Daphnia Test Toxi- city class ... 

Four bioassays a) 5 min acute bacterial test (Vibrio fischeri) b) 11 to 21 d algal test (Pseudokirchneriella subcapitata) c) 48h acute crustacean test (Daphnia magna) d) 96h acute fish test (Pimephales promelas) Municipal and industrial solid waste leachates originating from a sanitary landfill Filtered (glass fiber and 0.45 pm membrane filters for algal test) and unfiltered... 

Microplate algal test Selenastrum capricornutum Environment Canada SPE l/RM/25 (1992) Inhibition of growth Chronic... 

Table 5 summarizes pH, conductivity and ecotoxicological results obtained for each waste and each L/S ratio. For the Microtox test, a preliminary study (results not shown) had demonstrated that a 30-min exposure time was sufficient for testing 2SL leachates while 60 min was a more optimal time for testing the BA leachates. pH and conductivity values, obtained after water extraction (L/S of 2 and 10) of both wastes, were relatively high. Toxicity responses obtained from BA leachates varied from 4.2 TU (ceriodaphnid test, L/S 2) to 65.3 TU (algal test, L/S 2), whereas they... 

In contrast, the decreasing sensitivity sequence for the 2SL leachates was the following Microtox test > ceriodaphnid test > algal test daphnid test > Mutatox test. This indicates that the Microtox test should be the bioassay of choice to assess 2SL toxicity fluxes in the WASTOXHAS procedure. 

Results of the ecotoxic potential of leachate fluxes from BA waste are presented in Figure 7. Similarly results for the 2SL waste are presented in Figure 8. For each waste tested, bioassay responses showed adequate repeatability for the three replicate extraction columns (n = 3) employed. Indeed, averaged coefficients of variation determined with the Microtox test and the algal test were respectively 14.1% and 15.6% for columns filled with BA waste, and 19.4% and 27.3%, respectively, for columns filled with 2SL waste. 

Figure 7. Downward-flow column study - Toxicity responses of the Microtox test and the algal test on BA leachates in relation to the liquid-to-solid ratio (L/S).

Raw data for all bioassays, except algal test, were analyzed using the Toxcalc Toxicity Data Analysis and Database Software, vers. 5.0 (Tidepool Scientific Software). Point estimations were calculated by concentration/response regression using Probit Analysis as first choice and Trimmed Spearman-Karber as second, if Probit was not possible. If the raw data did not allow the respective L(E)C50 to be calculated at the highest tested concentrations, then these values... 

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