There were more current smokers in the high and medium exposure areas, but there were also more people with a university education.
Within the exposed population the proportion was 13.3% in the low-exposure area, 24.7% in the medium-exposure area and 26.7% in the high-exposure area.
We observed that the high ratio for children ≤ 5 years of age is more apparent in the high- and medium-exposure areas.
Allowing for this heterogeneity using a random-effects model to obtain overall summary estimates of the TTHM effects, small excess risks were found in the high- compared with low-exposure areas for stillbirths and low and very low birth weight of 11%9595% CI, 0 23%), 9% (95% CI, –7 27%), and 5%9595% CI, –18 34%), respectively, with intermediate risks in the medium-exposure areas (Table 2).
Average TTHM concentrations (±1 SD) for low, medium, and high exposure areas were 54 ± 16.6 μg/L, 109.3 ± 28.9 μg/L, and 137 ± 24 μg/L, respectively.
We calculated odds ratios (ORs) and 95% confidence intervals (CIs) for any BD and for categories of BDs using binomial logistic regression models, and calculated estimated risks for the medium and high exposure areas using the low exposure area as the comparison group.
For instance, we observed that the LICO only predicted access significantly within the medium and high exposure zones and not the low exposure area.
We observed that the low income only predicted access significantly within the medium and high exposure zones and not the low exposure area.
Children residing in areas with a soil contamination level of 165 265 kBq/m (medium exposure group in 1993 1998 cohort and the highest in 2008 2010) and consuming cow milk with higher Cs levels (>85 Bq/L) had higher levels of serum IgA as compared to the lowest exposure levels even 25 years after the incident.
Only one child came from the area with the second highest soil contamination level (266 349 kBq/m); this child was included in the medium exposure group.
