| Popis: |
The toxicity of three brands of hair shampoos (Vinoz, Gentelle and Petals) containing linear alkylbenzene sulphonates and used mostly for hair conditioning in beauty shops by woman in Nigeria were evaluated on fingerlings of the African catfish, Clarias gariepinus (mean weight=6.42 ± 0.2g; length=4.03 ± 0.1 cm). Specimens were exposed to 0.50%, 0.25%, 0.125%, 0.0625%, 0.03125% and 0.00% (control) toxicant concentrations during a 96-hours static bioassay. Mortality increased with concentrations and varied with brand of shampoo used; with the 0.50% toxicant concentration and Vinoz shampoo showing highest toxicity. LC50 for Vinoz, Gentelle and Petals were 0.0195%, 0.0281% and 0.0281% (arithmetic method), 0.9058%, 0.8873% and 0.8710% (logarithmic method) and 0.0172%, 0.0281% and 0.0177% (probit method) respectively. Survivorship of C. gariepinus was significantly homogeneous with Vinoz [F(1.56) Fcrit(4.13)] and heterogeneous with Petals shampoos [F(5.57)>Fcrit(4.13)] at P |
