Table 1:
Demographic characteristics of animal populations
| 2008 Birth Year | 2009 Birth year | P | |
|---|---|---|---|
| Participants | |||
| N | 8 | 14 | |
| Age at sample collection (yr) | 11.2±0.2 | 10.3±0.1 | P<0.001 |
| Weight at sample collection (kg) | 8.61±1.60 | 10.11±2.78 | 0.12 |
| Genetic background | |||
| Indian | 7 | 13 | 1.0 |
| Mixed Indian-Chinese | 1 | 1 | |
| Corral diversity | 8 | 13 | 1.0 |
| Maternal Background | |||
| Age at parturition (yr) | 5.5±1.7 | 5.8±2.5 | 0.8 |
| Genetic background | |||
| Indian | 7 | 12 | 1.0 |
| Mixed Indian-Chinese | 1 | 2 | |
| Corral diversity | 8 | 14 | 1.0 |
| Ambient pollutant during pregnancy | |||
| Days with PM2.5 higher than 35ug/m3 | 3±0 (38.2±1.5) | 1±0 (39.8±0) | N/A (0 SD) |
| Mean PM2.5 concentration (μg/m3) | 8.4±6.3 | 10.0±6.6 | 0.007 |
| Median PM2.5 concentration (μg/m3) | 6.5 (4.3–10.6) | 7.8 (5.1–13.4) | 0.007 |
| Ambient pollutants months 0–3 | |||
| Days with PM2.5 higher than 35ug/m3 | 10±1.0 (58.1±11.8) | 0±0 | P<0.0001 |
| Mean PM2.5 concentration (μg/m3) | 14.6±16.3 | 9.1±3.7 | P<0.0001 |
| Median PM2.5 concentration (μg/m3) | 9.5 (6.0–15.6) | 8.8 (6.4–11.4) | P<0.0001 |
| Hours over California 1-h ozone standard | 13±2.9 | 0±0 | P<0.0001 |
| Mean ozone level (ppm) | 0.032±0.020 | 0.029±0.017 | P<0.001 |
| Median ozone level (ppm) | 0.030 (0.016–0.045) | 0.027 (0.016–0.040) | P<0.001 |
| Cumulative exposures through sampling date | |||
| Days with PM2.5 higher than 35ug/m3 | 40±0 | 29±0.4 | P<0.0001 |
| Mean PM2.5 concentration (μg/m3) | 9.3±8.0 | 9.1±7.7 | P<0.0001 |
| Median PM2.5 concentration (μg/m3) | 8.4 (5.5–13.4) | 8.6 (6.3–11.4) | P<0.0001 |
| Hours over California 1-h ozone standard | 24±0 | 7±0 | N/A (0 SD) |
| Mean ozone level (ppm) | 0.026±0.015 | 0.026±0.015 | P<0.001 |
| Median ozone level (ppm) | 0.025 (0.015–0.036) | 0.025 (0.015–0.036) | P<0.001 |
Note: Age, weight and exposures are shown as mean ± (SD) or median (interquartile range), and compared using t test. Categorical variables (genetic background and corral diversity) are reported as group-specific numerical frequency and compared using Fisher’s exact tests. 35ug/m3 is the 24-hour PM2.5 National Ambient Air Quality Standard. 0.09ppm is the California 1-h ozone standard. For the “Days with PM2.5 higher than 35ug/m3” rows, the mean ± SD of the exposure levels in μg/m3 for those days are shown in parentheses.