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. 2023 Jan 6;867:161423. doi: 10.1016/j.scitotenv.2023.161423

Table 5.

Comparison of microbiological targets for grab versus composite samples produced in the laboratory from samples collected from wastewater source each hour (Experiments 1-3B). p values of the one-sample t-test <0.05 indicate that the mean of the grab sample was statistically different than the value of the corresponding composite sample.

Molecular and Microbial Targets SARS-CoV-2 (gc/L) SIV (gc/L) PMMoV (gc/L) B2M (gc/L) FC (CFU/L)
Sample Type Experiment 1B - Building Scale
Grab Average (n = 24) 5.28 × 104 3.08 × 106 2.43 × 108 8.81 × 105 2.30 × 107
Grab Median (n = 24) 4.55 × 103 2.32 × 106 1.32 × 108 8.58 × 105 9.00 × 106
Grab [Min-Max](Std. Dev) [BDL⁎-9.7 × 105] (2.0 × 105) [1.3 × 105–1.2 × 107] (2.7 × 106) [6.0 × 107–1.9 × 109] (3.8 × 108) [5.0 × 103–1.6 × 106] (4.1 × 105) [BDL⁎-1.9 × 108] (4.0 × 107)
Composite 1B 4.13 × 104 1.6 × 105 3.70 × 108 9.31 × 105 1.74 × 108
One-Sample t-test (p-value: two-tailed) 0.775⁎⁎ <0.001 0.112⁎⁎ 0.567⁎⁎ <0.001



Sample Type Experiment 2B - Cluster Scale
Grab Average (n = 24) 2.82 × 105 7.26 × 106 1.38 × 108 1.08 × 106 2.42 × 107
Grab Median (n = 24) 1.75 × 105 6.95 × 106 1.40 × 108 1.05 × 106 1.00 × 107
Grab [Min-Max](Std. Dev) [6.2 × 104–2.0 × 106] (3.9 × 105) [3.8 × 106–1.2 × 107] (2.4 × 106) [5.8 × 107–2.6 × 108] (5.2 × 107) [4.8 × 105–2.0 × 106] (4.5 × 105) [1.0 × 103–1.5 × 108] (3.2 × 107)
Composite 2B 3.16 × 105 4.38 × 105 1.27 × 108 9.59 × 105 6.80 × 107
One-Sample t-test (p-value: two-tailed) 0.669⁎⁎ <0.001 0.319⁎⁎ 0.217⁎⁎ <0.001



Sample Type Experiment 3B - Community Scale
Grab Average (n = 24) 8.62 × 103 4.30 × 106 1.43 × 108 2.43 × 105 1.02 × 108
Grab Median (n = 24) 7.63 × 103 4.59 × 106 1.50 × 108 2.61 × 105 9.50 × 107
Grab [Min-Max](Std. Dev) [8.4 × 102–3.0 × 104] (6.1 × 103) [2.2 × 106–6.5 × 106] (1.1 × 106) [9.1 × 107–2.1 × 108] (3.2 × 107) [1.2 × 105–3.6 × 105] (7.0 × 104) [3.7 × 107–1.7 × 108] (4.0 × 107)
Composite 3B 1.16 × 104 6.07 × 105 1.66 × 108 2.25 × 105 4.21 × 108
WWTP Composite 9.12 × 103 6.22 × 106 1.78 × 108 2.90 × 105 2.38 × 108
One-Sample t-test (p-value: two-tailed) 0.022 (UM)
0.689⁎⁎ (WWTP)		 <0.001 (UM)
<0.001 (WWTP)		 0.002 (UM)
<0.001 (WWTP)		 0.227⁎⁎ (UM)
0.003 (WWTP)		 <0.001 (UM)
<0.001 (WWTP)
⁎

BDL = Below Detection Limits. Detection limit for SARS-CoV-2 was 1.0 × 102 gc/L. Detection limit for FC was 1.0 × 106 CFU/L.

⁎⁎

denotes statistical equivalency between grab and composite sample types by Wilcoxon Signed Rank Tests/t-tests.