Table 2. Analysis of a Set of 30 Environmental Water Sample DNA Extracts with and without a History of Fecal Pollutiona.
| DNA extract sample | HDA | qPCRb | mean copy number ± standard deviation determined by qPCRb |
|---|---|---|---|
| Spring/Groundwater Samples (unpolluted) | |||
| GW1 | 0/3 | 0/3 | undetermined |
| GW2 | 0/3 | 0/3 | undetermined |
| GW3 | 0/3 | 0/3 | undetermined |
| GW4 | 0/3 | 0/3 | undetermined |
| GW5 | 0/3 | 0/3 | undetermined |
| SW1 | 0/3 | 0/3 | undetermined |
| SW2 | 0/3 | 0/3 | undetermined |
| SW3 | 0/3 | 0/3 | undetermined |
| SW4 | 0/3 | 0/3 | undetermined |
| SW5 | 0/3 | 0/3 | undetermined |
| Surface Water/Polluted Spring Water Samples (moderately polluted) | |||
| JDS1 | 0/3 | 0/3 | undetermined |
| JDS2 | 1/3 | 3/3 | 6 ± 2 |
| JDS3 | 3/3 | 3/3 | 29 ± 4 |
| JDS4 | 3/3 | 3/3 | 37 ± 9 |
| JDS5 | 2/3 | 3/3 | 19 ± 5 |
| SFW1 | 0/3 | 0/3 | undetermined |
| SFW2 | 3/3 | 3/3 | 156 ± 16 |
| SFW3 | 3/3 | 3/3 | 71 ± 10 |
| SFW4 | 0/3 | 0/3 | undetermined |
| SFW5 | 3/3 | 3/3 | 12 ± 6 |
| Wastewater Samples (highly polluted) | |||
| WWTP1 effluent | 3/3 | 3/3 | 10666 ± 730 |
| WWTP2 effluent | 3/3 | 3/3 | 3369 ± 510 |
| WWTP3 effluent | 3/3 | 3/3 | 1541 ± 172 |
| WWTP4 effluent | 3/3 | 3/3 | 2531 ± 207 |
| WWTP5 effluent | 3/3 | 3/3 | 5803 ± 580 |
| WWTP1 influent | 3/3 | 3/3 | 53085 ± 581 |
| WWTP2 influent | 3/3 | 3/3 | 45690 ± 4073 |
| WWTP3 influent | 3/3 | 3/3 | 41370 ± 1147 |
| WWTP4 influent | 3/3 | 3/3 | 138544 ± 9201 |
| WWTP5 influent | 3/3 | 3/3 | 37803 ± 3354 |
a
All DNA extracts were measured with HDA and qPCR in parallel. The results of both methods are indicated as the number of positives in triplicate analysis. Results of qPCR were scored negative when the ct value was undetermined or <1 copy was detected. Abbreviations: GW, groundwater; SW, spring water; JDS, Joint Danube Survey; SFW, surface water; WWTP, wastewater treatment plant.
b
qPCR data have also been used as a cross-comparison by Martzy et al.57