Determination of maximum allowable concentration and LC50 96h of Sefidroud River sediments for Persian sturgeon (Acipenser persicus) fingerlings

The impact of Sefidroud River sediments on the fingerlings of Persian Sturgeon (Acipenser persicus) was studied in 2005. The tests were done in 20 liter aquariums each containing 10 Persian Sturgeons fingerlings weighing 3-5 grams each. We devised 6 treatments and a control with 3 repetitions in the four day investigation through which the lethal concentration (LC50 96h) of Sefidroud sediments were studied. During the test, physicochemical parameters of water such as pH, oxygen and temperature were measured as 8, 8.5mg/1 and 25±1°C respectively. The results showed that LC5096h and LC50 24h of sediments on Persian sturgeon were 15367.39mg/1 and 124882.04mg/1 respectively. We determined the maximum allow-able concentration (M.A.C) of sediments to be I 536.74mg/l

Determination of LC_(50) 96h of dyazinon, hinosan and tilt for Acipenser nudiventris fingerlings

The toxic effects of agricultural pesticides Dyazinon, Hinosan and Tilt (Propiconazole) were studied on Acipenser nudiventris fingerlings (1-3g) in Spring 2005. We conducted our experiments in aquaria holding 20L water in static systems based on O.E.C.D method using five treatments, one control concentration and three replications. In each aquarium, ten individual Ship Sturgeon fingerlings were introduced, and water physical and chemical factors were controlled to be in the range pH=7-8, TH>400mg/l (CaCO _(3)) as for the water used for culture, and DO=80% and temperature was kept between 24 ±1°C. Our results for the LC _(50) value of Dyazinon, Hinosan and Tilt in 96 hours were 0.36, 0.28 and 3.9mg/l in the fish fingerlings. We also determined the maximum allowable concentration value of the toxins at 0.036, 0.028 and 0.39, respectively