Table 4 Descriptive statistics of dietary nitrate, nitrite, and nitrosamine intake and oral cleft defects in offspring
| Â | Â | Â | Â | N (%) | |||
|---|---|---|---|---|---|---|---|
|  |     Outcome | N | Mean (SD) | Quartile 1 | Quartile 2 | Quartile 3 | Quartile 4 |
Nitrate (mg/day) | Â | Â | Â | Â | Â | Â | |
| Â | Cleft lip only | 613 | 50.31 (52.16) | 165 (26.9) | 162 (26.4) | 139 (22.7) | 147 (24.0) |
| Â | Cleft lip with cleft palate | 1133 | 48.65 (37.08) | 293 (25.9) | 309 (27.3) | 273 (24.1) | 258 (22.8) |
| Â | Cleft palate only | 910 | 49.86 (36.66) | 230 (25.3) | 233 (25.6) | 224 (24.6) | 223 (24.5) |
| Â | Cleft lip with or without cleft palate | 1746 | 49.23 (42.97) | 458 (26.2) | 471 (27.0) | 412 (23.6) | 405 (23.2) |
Nitrite (mg/day) | Â | Â | Â | Â | Â | Â | |
| Â | Cleft lip only | 614 | 1.75 (0.97) | 166 (27.0) | 136 (22.1) | 158 (25.7) | 154 (25.1) |
| Â | Cleft lip with cleft palate | 1133 | 1.88 (1.06) | 263 (23.2) | 262 (23.1) | 275 (24.3) | 333 (29.4) |
| Â | Cleft palate only | 910 | 1.72 (0.96) | 257 (28.2) | 211 (23.2) | 228 (25.1) | 214 (23.5) |
| Â | Cleft lip with or without cleft palate | 1747 | 1.83 (1.03) | 429 (24.6) | 398 (22.8) | 433 (24.8) | 487 (27.9) |
Animal Nitrite (mg/day) | Â | Â | Â | Â | Â | Â | |
| Â | Cleft lip only | 615 | 1.11 (0.75) | 151 (24.6) | 149 (24.2) | 144 (23.4) | 171 (27.8) |
| Â | Cleft lip with cleft palate | 1140 | 1.17 (0.78) | 262 (23.0) | 275 (24.1) | 269 (23.6) | 334 (29.3) |
| Â | Cleft palate only | 918 | 1.07 (0.71) | 249 (27.1) | 219 (23.9) | 230 (25.1) | 220 (24.0) |
| Â | Cleft lip with or without cleft palate | 1755 | 1.15 (0.77) | 413 (23.5) | 424 (24.2) | 413 (23.5) | 505 (28.8) |
Plant Nitrite (mg/day) | Â | Â | Â | Â | Â | Â | |
| Â | Cleft lip only | 614 | 0.64 (0.38) | 153 (24.9) | 160 (26.1) | 162 (26.4) | 139 (22.6) |
| Â | Cleft lip with cleft palate | 1140 | 0.71 (0.49) | 280 (24.6) | 274 (24.0) | 261 (22.9) | 325 (28.5) |
| Â | Cleft palate only | 914 | 0.65 (0.41) | 242 (26.5) | 221 (24.2) | 251 (27.5) | 200 (21.9) |
| Â | Cleft lip with or without cleft palate | 1754 | 0.69 (0.45) | 433 (24.7) | 434 (24.7) | 423 (24.1) | 464 (26.5) |
Nitrosamine (μg/day) |  |  |  |  |  |  | |
| Â | Cleft lip only | 614 | 0.72 (4.60) | 169 (27.5) | 126 (20.5) | 171 (27.9) | 148 (24.1) |
| Â | Cleft lip with cleft palate | 1133 | 0.53 (0.31) | 302 (26.7) | 269 (23.7) | 283 (25.0) | 279 (24.6) |
| Â | Cleft palate only | 908 | 0.52 (0.30) | 264 (29.1) | 226 (24.9) | 209 (23.0) | 209 (23.0) |
| Â | Cleft lip with or without cleft palate | 1747 | 0.60 (2.74) | 471 (27.0) | 395 (22.6) | 454 (26.0) | 427 (24.4) |