Ecotoxicological evaluation of construction products: inter-laboratory test with DSLT and percolation test eluates in an aquatic biotest battery

Background A European inter-laboratory test with 29 participating laboratories investigated whether a battery of four ecotoxicological tests is suitable for assessing the environmental compatibility of construction products. For this purpose, a construction product was investigated with the dynamic surface leaching test (DIN CEN/TS 16637-2) and the percolation test (DIN CEN/TS 16637-3). The eluates were produced centrally by one laboratory and were tested by the participants using the following biotests: algae test (ISO 8692), acute daphnia test (ISO 6341), luminescent bacteria test (DIN EN ISO 11348), and fish egg test (DIN EN ISO 15088). As toxicity measures, EC50 and LID values were calculated. Results Toxic effects of the eluates were detected by all four biotests. The bacteria test was by far the most sensitive, followed by the algae test and the daphnia test; the fish egg test was the least sensitive for eluates of both leaching tests. The toxicity level of the eluates was very high in the bacteria, daphnia, and algae test, with lowest ineffective dilution values of LID = 70 to LID = 13,000 and corresponding EC50 values around or even below 1 volume percent. The reproducibility (approximated by interlaboratory variability) of the biotests was good (< 53%) to very good (< 20%), regardless of the toxicity level of the eluates. The reproducibility of the algae test was up to 80%, and thus still acceptable. Conclusion It can be confirmed that the combination of leaching and ecotoxicity tests is suitable to characterize with sufficient reproducibility the environmental impact posed by the release of hazardous substances from construction products.

Assessment of predatory ability of native and non-native freshwater gammaridean species: A rapid test with water fleas as prey

Predation rate with relation to species, sex and water temperature was tested among four different gammaridean species: Dikerogammarus villosus, Gammarus roeselii, Gammarus pulex and Gammarus fossarum. Tests were performed in microcosms in climate-controlled rooms at five different temperatures. Daphnia magna, a common water flea, served as prey. On average D. villosus showed the highest consumption rate of Daphnia magna over the entire temperature range, followed in decreasing order by G. p u le x , G. roeselii and G. fossarum. The predation rate of all species showed a distinct peak at 20°C. Correction of predation rates for body size gave somewhat different results. D. villosus is then still the most predatory of all gammaridean species tested followed by G. pulex, G. fossarum and G. roeselii. The outcome of the Daphnia tests is consistent with results of other studies with different prey. This supports that the Daphnia test is a good and quick indicator of the predatory abilities in gammaridean species at varying temperatures, and allows the prediction of how changing temperature regimes influence invasion impacts.

Toxicity and Genotoxicity Testing of Roundup

Toxicity and Genotoxicity Testing of Roundup Glyphosate, in the commercial formulation named Roundup, is a broad spectrum herbicide that is one of the most frequently applied pesticides in the world. However, there has been little evidence of Roundup toxicity or genotoxicity. Genotoxicity of glyphosate was carried out using the Escherichia coli SOS chromotest. The glyphosate-induced dose response in the SOS chromotest suggests that glyphosate possesses genotoxic properties. Glyphosate at a 0.2 g/l concentration in toxicity bioassay caused 50% mortality of Daphnia magna (LD50 after 24 h — 0.22 g/l; after 48 h — 0.19 g/l), but 0.25 — 0.5 g/l — 100% death of organisms (LD100 after 24 h — 0.5 g/l; after 48 h — 0.25 g/l). Our results (E. coli SOS chromotest and daphnia test system) together with recent animal studies and epidemiological reports suggest that glyphosate, especially, Roundup possesses both toxic and genotoxic properties.