Chapter 12
Sampling, sample preparation and dosing
How can you find out how well the bioassay response is recovered in your water sample after solid-phase extraction? Do you need to do recovery experiments each time you perform an SPE?
You collected the following samples and performed solid phase extraction (SPE) with them. Calculate the enrichment factor.
| Water sampled | SPE extract (methanol) | |
|---|---|---|
| WWTP influent | 0.5L | 500 µL |
| WWTP effluent | 1L | 500 µL |
| Surface water | 2L | 500 µL |
| Drinking water | 4L | 500 µL |
| SPE Blank | ?? | 500 µL |
How would you need to prepare the SPE Blank for the samples in 12B2? Is one SPE blank sufficient? What volume should the blank(s) have?
You are charged with assessing the treatment efficacy of a drinking water treatment plant. Source water is riverbank filtrate, which is first coagulated, then settled and treated with chloramine before it is sent to the consumers in a pipeline. At which stages of the plant would you take samples? Would you take grab samples or 24h-composite samples? Or would you sample over a longer time period? What volume of sample would you take for each sample type? How would you pretreat the sample and how would you extract it? If you have already had a look at chapter 10 and 13, which bioassays would you chose?