Table 3.
Number (percentages) of samples by decimal E. coli concentrations in household drinking water during the cross-sectional survey of continued concrete BSF use in Bonao, Dominican Republic, from June to July of 2007
| Study households | E. coli concentration* | ||||||
|---|---|---|---|---|---|---|---|
| < 1 N (%) | 1–10 N (%) | 11–100 N (%) | 101–1,000 N (%) | 1,001+ N (%) | Total (N) | Geometric mean† | |
| All untreated | 19 (11%) | 36 (22%) | 63 (38%) | 37 (22%) | 12 (7%) | 167 | 28.3 |
| All BSF‡ | 68 (40%) | 65 (35%) | 28 (16%) | 7 (4%) | 2 (1%) | 170 | 3.3 |
*
MPN E. coli per 100 mL.
†
Geometric mean concentrations were significantly different (P < 0.001) by two-sample t test.
‡
Water was direct from concrete BSF outlet pipe.