Acute Toxicity of the Preparation PAX-18 for Juvenile and Embryonic Stages of Zebrafish (Danio rerio)

The preparation PAX-18 is a coagulation agent, which is used in water and wastewater treatment facilities and for the treatment of natural waters. The active compound is polyaluminium chloride (9% of Al). The application to the water environment could present a potential risk to different developmental stages of fish. The aim of this study was to assess and compare the toxicity of the preparation PAX-18 for embryonic and juvenile developmental stages of zebrafish ( Danio rerio ). The acute toxicity tests with juvenile fish aged 2–3 months were conducted according to the method OECD No. 203 in 5 series. For embryo toxicity test the method OECD No. 212 was used in 5 series. The semistatic methods were selected. The results of toxicity tests (the number of dead individuals at particular test concentrations) were subjected to probit analysis using the EKO-TOX 5.2 programme to determine LC50 values of PAX. The LC50 mean value of PAX for juvenile D. rerio was 749.7 ± 30.6 mg·l -1 (67.5 ± 2.8 mg·l -1 of Al) and 731.5 ± 94.1 mg·l -1 (65.8 ± 8.5 mg·l -1 of Al) for embryonic stages of D. rerio. The sensitivity of juvenile and embryonic stages to PAX were comparable ( p > 0.01). The acute toxicity values of PAX-18 found in tests on D. rerio were 6–13 × higher than the concentration which is usually applied to waters (5–10 mg·l -1 of Al). Therefore, the acute toxicity effect on fish can be considered minimal.