Background To explore possible causes of a 1988 incidence peak of infa
nt neuroblastoma in west German regions which were contaminated with m
ore than 6000 Bq/m(2) Cs137 from the Chernobyl accident. The primary w
orking hypothesis was that parents of the diseased children had been c
ontaminated by an excessive intake of locally produced food, especiall
y mushrooms or deer. Design Case control study with 1:2 (cases:control
s) matching. Data were collected from the children's parents by questi
onnaires and telephone interviews. Setting Nation-wide study (former F
RG) based on the German Childhood Cancer Registry. Subjects Cases born
in 1988 and reported with a neuroblastoma to the registry until March
1992. Population-based healthy controls, matched for age, sex and res
idence at time of diagnosis. Results The working hypothesis could not
be confirmed by the study, because the parents of cases tended to eat
less locally grown food than the parents of controls (RR = 0.63, 95% C
I: 0.20-1.97). Possible influence factors which previously have been d
escribed to be associated with neuroblastoma incidence could not be co
nfirmed by the study. Parental exposure to herbicides and pesticides w
as associated with the occurance of neuroblastoma (RR = 4.2. 95% CI: 1
.4-12.9). Neuroblastoma stage distribution in the contaminated regions
was shifted towards lower stages as compared to the less contaminated
regions and previous age cohorts. Conclusions The study does not show
additional evidence that the observed increase in neuroblastoma incid
ence might have been caused by exposure to fallout from the Chernobyl
accident, The observed shift towards lower clinical stages may rather
indicate increased diagnostic awareness. The association between neuro
blastoma and parental exposure with herbicides and pesticides resulted
from an extensive exploratory data analysis and needs to be confirmed
in further studies.