Division 1.8.2 Selection and number of aquatic sediments
United Kingdom
The sampling sites should be selected in accordance with the purpose of the test in any given situation. In selecting sampling sites, the history of possible agricultural, industrial or domestic inputs to the catchment and the waters upstream must be considered. Sediments should not be used if they have been contaminated with the test substance or its structural analogues within the previous 4 years.
Measurement of parameters for characterisation of water-sediment samples (7)(22)(23)
| Recent research results have shown that measurements of water oxygen concentrations and of redox potentials have neither a mechanistic nor a predictive value as far as growth and development of microbial populations in surface waters are concerned (24)(25). Determination of the biochemical oxygen demand (BOD, at field sampling, start and end of test) and of concentrations of micro/macro nutrients Ca, Mg and Mn (at start and end of test) in water and the measurement of total N and total P in sediments (at field sampling and end of test) may be better tools to interpret and evaluate aerobic biotransformation rates and routes. | ||||||
| Microbial respiration rate method (26), fumigation method (27) or plate count measurements (e.g. bacteria, actinomycetes, fungi and total colonies) for aerobic studies; methanogenesis rate for anaerobic studies. | ||||||
| Parameter | Stage of test procedure | |||||
|---|---|---|---|---|---|---|
| field sampling | post-handling | start of acclimation | start of test | during test | end of test | |
| Water | ||||||
| Origin/source | X | |||||
| Temperature | X | |||||
| PH | X | X | X | X | X | |
| TOC | X | X | X | |||
| O2 concentrationf1 | X | X | X | X | X | |
| Redox Potential | X | X | X | X | ||
| Sediment | ||||||
| Origin/source | X | |||||
| Depth of layer | X | |||||
| PH | X | X | X | X | X | |
| Particle size distribution | X | |||||
| TOC | X | X | X | X | ||
| Microbial biomassf2 | X | X | X | |||
| Redox potential | Observation (colour/smell) | X | X | X | X | |
Annotations
Footnotes
- f1
-
Recent research results have shown that measurements of water oxygen concentrations and of redox potentials have neither a mechanistic nor a predictive value as far as growth and development of microbial populations in surface waters are concerned (24)(25). Determination of the biochemical oxygen demand (BOD, at field sampling, start and end of test) and of concentrations of micro/macro nutrients Ca, Mg and Mn (at start and end of test) in water and the measurement of total N and total P in sediments (at field sampling and end of test) may be better tools to interpret and evaluate aerobic biotransformation rates and routes.
- f2
-
Microbial respiration rate method (26), fumigation method (27) or plate count measurements (e.g. bacteria, actinomycetes, fungi and total colonies) for aerobic studies; methanogenesis rate for anaerobic studies.