Detection
It is important to know the minimum amount of a contaminant that a laboratory can detect.
Here are examples of Minimum Acceptable Method Detection Limits for heavy metals used by the USFWS Patuxent Lab:
| ANALYTE | TISSUES (parts per million, dry weight) | SOIL, SEDIMENT (parts per million, dry weight) | WATER (parts per million, wet weight) |
| mercury | .2 | .2 | .004 |
| cadmium | .1 | .2 | .0005 |
| selenium | .5 | 1.0 | .005 |
Examples of Minimum Acceptable Method Detection Limits for persistent organic pollutants
| ANALYTE | TISSUES (parts per million, wet weight) | SOIL, SEDIMENT (parts per million, dry weight) | WATER (parts per million, wet weight) |
| DDT | .01 | .01 | .001 |
| Toxaphene | .05 | .05 | .005 |
| PCB Congeners | .00001 | .00001 | as low as possible |
Please continue with "Precision".
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