Potamothrix hammoniensis
[ref. ID; 7044]
Test system
Bioassay
Strains
Worms were collected from Gorvaln Bay of Lake Malaren, central Sweden. Small worms (less than one week old and weighing about 0.2 mg).
Toxicants
Sediment (Lake Hjalmaren, Lake Malaren, Lake Rogsjon, Lake Runn).
Test design
Experiments were conducted in darkness at 21+/-1 degrees C in vessels 5.5 cm wide, 7 cm high, with a sediment depth of 1.5 cm and with 50% aerated tap water and 50% deionized water above the sediment surface. 5 worms. Different food conditions (0, 25, 75 mg/week). Experimental period 500 days.
Measurements/observations
Number and weight.
Evaluations
Growth rate.