Congenital abnormalities and indicators of germinal mutations in the vicinity of an acrylonitrile producing factory.

The results of an environmental mutation and teratologic epidemiological study are presented which was performed in inhabitants living in the surrounding region of an acrylonitrile factory in Nyergesújfalu. The endpoint of the study was congenital abnormalities in 46,326 infants born to mothers living in the 30 settlements of the study region within a 25 km radius of the acrylonitrile factory between 1980 and 1996. The ascertainment of cases with congenital abnormalities was based on the dataset of the Hungarian Congenital Abnormality Registry complemented with the review of pediatric, pathology and cytogenetic records. A particular attention was paid to the indicators of germinal mutations as sentinel anomalies, Down syndrome and unidentified multiple congenital abnormalities and the indicators of teratogens as the specific pattern of multiple congenital abnormalities. Three congenital abnormalities: pectus excavatum in Tata, 1990-1992 (OR with 95%CI: 78.5, 8.4-729.6), undescended testis in Nyergesújfalu between 1980 and 1983 (8.6, 1.4-54.3) and in Esztergom, 1981-1982 (4. 2, 1.3-13.5) and clubfoot in Tata, 1980-1981 (5.5, 1.5-20.3) showed significant time-space clusters in the study region. There was a decrease in risk of undescended testis with increasing distance from the acrylonitrile factory. An unusual increase was found in the combination of oral cleft and cardiac septal defects in multimalformed babies in Tatabánya, 1990. The detailed analysis of congenital abnormalities in all settlements of a given territory may help to detect clusters of congenital abnormalities and their possible relation to the environmental hazards.