Risk of Congenital Anomalies Around a Municipal Solid Waste Incinerator - Recent Advances and Issues in Environmental Science - page 111

Figure 2. Operation periods of the municipal waste incinerator of Reggio Emilia, Italy, and
corresponding exposure status of cohorts of births and of aborted foetuses undergoing a diagnosis of
congenital anomaly during the 1998-2006 period.

Overall, we identifi ed 228 cases of congenital anomalies during the study period:
183 live- and stillbirths presenting one or more defects or congenital syndrome and
45 induced abortions of foetuses with single or multiple anomalies. Maternal age of
case mothers (at birth or at time of abortion) ranged from 16 to 44 years; regarding
educational attainment level, case and referent mothers who had attended elementary
school were 19 (8.33%) and 9 (3.95%) respectively, middle school 83 (36.40%) and 78
(34.21%), high school in 90 (39.47%) and 104 (45.61%), and university 36 (15.79%)
and 37 (16.23%).
Using a logistic regression model and adjusting for education and maternal age,
OR for congenital anomalies was 1.49 (95% CI 0.70-3.19) in the medium exposure
group and 0.66 (95% CI 0.25-1.79) in the high exposure group, compared to the re-
maining municipal population (Table 1), and results were substantially similar when
we used a conditional logistic model (Table 2). As summarized in Table 1, grouping
together the two highest exposure levels OR in the overall exposed population re-
sulted to be 1.11 (95% CI 0.60-2.04), and when the analysis was carried out for single
anomaly categories we found little evidence of excess risk for any disease group and
exposure status, with the exception of an increased OR for chromosomal abnormali-
ties in the middle exposure area (OR 2.53, 95% CI 0.88-7.24).

Table 1. Prevalence odds ratio for congenital anomalies associated with maternal exposure to the
emissions of the incinerator plant of Reggio Emilia, northern Italy, 1998-2006.

Area Cases% (n) Controls% (n) Odds ratio l

All anomalies
A (low exposure) 89.0 (203) 90.4 (206) 1.00 (referent)

B (medium exposure) 7.9 (18) 5.3 (12) 1.49 (0.70-3.19)

C (high exposure) 3.1 (7) 4.3 (10) 0.66 (0.25-1.79)

P trend 0.881

Overall exposed area (B+C) 11.0 (25) 9.6 (22) 1.11(0.60-2,04)

Cardiovascular system
A (low exposure) 9.6 (87) 90.4 (206) 1.00 (referent)

B (medium exposure) 6.3 (6) 5.3 (12) 0.91 (0.36-2.31)

C (high exposure) 3.1 (3) 4.3 (10) 0.77 (0.22-2.77)

P trend 0.666