Biological test method for determining acute lethality of sediment to amphipods: chapter 3

Section 3: Facilities, Equipment, and Supplies

Facilities used to hold and acclimate amphipods, and to undertake toxicity tests, must be well ventilated, free of fumes, and isolated from physical disturbances or airborne contaminants that might affect the test organisms. The testing facility should be isolated from the area where amphipods are being held and acclimated to test conditions. The holding/acclimation and testing facilities should also be isolated from areas where test sediments or stock solutions of chemicals are prepared, and removed from areas where equipment is cleaned.

The separate facilities where organisms are acclimated and tests are performed must enable the temperature of the water overlying sediment to be held within the desired range (i.e., 15 ± 2°C for R. abronius, E. washingtonianus, or E. estuarius; and 10 ± 2°C for A. virginiana). This may be achieved using environmental chambers, temperature-controlled recirculating water baths, or equivalent facilities with rigorous temperature control. Overhead lighting by fluorescent or equivalent broad-spectrum illumination should provide a light intensity of 500 to 1000 lux adjacent to the surface of the overlying water, in both the holding/acclimation and testing facilities.

Equipment and supplies which contact sediments, water, or stock solutions must not contain substances that can be leached or dissolved in amounts that adversely affect the test organisms, and should be chosen carefully to minimize sorption of materials from water. Guidance provided in Section 2.5.2 of Environment Canada (1992) should be followed when choosing equipment and supplies.

High-density plastic containers are recommended for holding and acclimating amphipods. Glass containers (beakers or wide-mouthed jars) with a capacity of approximately 1 L and an internal diameter of approximately 10 cm, together with suitable covers (e.g., watch glasses or plastic lids) must be used as test chambers. All test chambers and other equipment that come in contact with sediment, water, or test organisms must be cleaned, and rinsed just before use (see guidance in Section 3.3 of Environment Canada, 1992).