Table 2 Rates of congenital anomalies per 100 000 birth-years by categories of the landfill exposure index, unadjusted odds ratios (OR) (95% confidence intervals) and adjusted OR* (95% credible intervals)
Landfill exposure index
1234
Median (range)0 (0)0.10 (0.01–0.29)0.57 (0.30–0.95)1.75 (0.96–12.24)
Squares, n1751122912511206
Births, n966 5131 775 2542 766 9784 620 542
All anomalies
    Rate1260.41322.21335.31389.9
    Unadjusted OR1.001.05 (1.03 to 1.07)1.06 (1.04 to 1.08)1.10 (1.08 to 1.12)
    Adjusted OR1.001.00 (0.95 to 1.05)0.99 (0.94 to 1.03)1.02 (0.98 to 1.07)
Hypospadias and epispadias
    Rate118.3113.8113.7129.1
    Unadjusted OR1.000.96 (0.90 to 1.03)0.96 (0.90 to 1.03)1.09 (1.03 to 1.16)
    Adjusted OR1.000.91 (0.83 to 1.01)0.91 (0.82 to 1.00)0.97 (0.89 to 1.06)
Neural tube defects
    Rate48.552.553.858.8
    Unadjusted OR1.001.08 (0.97 to 1.21)1.11 (1.00 to 1.23)1.21 (1.10 to 1.34)
    Adjusted OR1.001.07 (0.94 to 1.22)1.06 (0.93 to 1.19)1.04 (0.93 to 1.18)
Cardiovascular defects
    Rate77.784.783.987.3
    Unadjusted OR1.001.09 (1.00 to 1.19)1.08 (0.99 to 1.17)1.12 (1.04 to 1.22)
    Adjusted OR1.000.93 (0.81 to 1.07)0.95 (0.83 to 1.09)0.94 (0.82 to 1.07)
Abdominal wall defects
    Rate20.421.523.725.0
    Unadjusted OR1.001.05 (0.89 to 1.25)1.16 (1.00 to 1.37)1.23 (1.06 to 1.43)
    Adjusted OR1.001.08 (0.90 to 1.3)1.15 (0.97 to 1.37)1.11 (0.94 to 1.32)
  • *Adjusted in the Bayesian hierarchical logistic regression model for deprivation, the presence or absence of a local registry and maternal age.

  • Values for non-special or unknown waste sites operational at some time between 1982 and 1997.