Introduction and objective:
The most common cancers in children are leukemias, which account for approximately 25% of all cancers diagnosed in children in Poland. During 1999–2016, a total of 4,905 children and adolescents fell ill with leukemia, of whom 1,479 died. The study assumes that the exposure of parents in the pre-contraceptive period and the exposure of their children in the prenatal period to environmental carcinogens may influence the development of leukemia. Objective. The aim of this study was to analyze the occurrence of health risk factors in the families of children suffering from leukemia, caused by environmental pollution or the lifestyle of their parents.

Material and methods:
To achieve the assumed goal, a questionnaire study was conducted among 100 parents/legal guardians of children treated for leukemia.

Statistical analyses of the data obtained showed a statistically significant correlation between the occurrence of leukemia in a child and: the child's age at diagnosis of the disease (p<.047), consumption of vegetables from their own cultivation by the respondents and their children (p<.048), and the use of plant protection products and artificial fertilizers in arable fields, allotment and home gardens owned by the respondents (p<.003).

In order to reduce the health risk associated with the occurrence of neoplastic diseases of the blood in the population of children, actions should be taken to increase the awareness of the general population about the presence of carcinogenic and haematotoxic factors in the human living environment.

Funding. The study was funded by the Medical University of Silesia in Katowice, Poland (Grant No. KNW-1–094/ N/7/Z and KNW-1–99/N/9/Z).
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