[Case control study of the relationship between local environmental factors and hematopoietic malignancies in young subjects in Aalsmeer].

In Aalsmeer, a horticultural community near the main international airport in the Netherlands, an incidence of haematopoietic malignancies in young people over four times the national mean was observed in the period 1980-1985. A population based case-control study investigated the association with local environmental factors. For each case younger than 40 years of age (n = 14), diagnosed between 1975 and 1989, four controls, matched for age and gender, were selected via local general practitioners. All parents of patients and controls completed a questionnaire on their life style, living conditions and health for several years preceding each individual diagnosis. Odds ratios (ORs) were calculated, matched and--if necessary--stratified for neighbourhood. Increased ORs were recorded for intensive use of petroleum products and pesticides, by the patients themselves and their fathers (OR petroleum products: 8.0, resp. 9.0; OR pesticides: 6.0, resp. 3.2). Most of these increases were statistically significant. Swimming in a local pond was also significantly associated with the disease (OR = 5.3); in the seventies this pond had been polluted by accidents with petroleum products and pesticides. contributed to the increase of the disease: ORs for several indirect exposure parameters were all above 2. It can be concluded that the increased incidence of childhood haematopoietic malignancies in Aalsmeer may have been associated with several specific local environmental factors. However, interpretation of the results should take into account that confidence intervals were wide, due to the necessarily limited number of cases.