Effects of solar radiation and woodsmoke on risk of childhood leukaemia: system analysis
Radiation is recognized risk factor for childhood leukemia. The impact of tobacco smoke and traffic-related pollutants on risk of leukemia development in children is discussed. To study relationship between solar activity, wood smoke and risk of leukemia in children is very important for understanding the situation in a specific area, as well as for acquiring new knowledge of causes of this type of hemoblastoses. The paper presents system analysis of effects of exposure to solar radiation and wood smoke on risk for leukemia development in young children at 0-4 years, resided in the Khabarovsk region. Authors studied more accurate information on leukemia incidence among children at 0-4 years, born from 1972 to 1988. To study effects of solar activity and amount of wildfires in 1-2-3 years before and after the birth of the children on leukemia rate in the cohort under study multivariate analysis was used. Linear relationship between leukemia rate and amount of wildfires 2 years before the birth of the children (r=0.465; p=0.060) and solar activity in 3 years after the birth (r=0.567; p=0.018) was found. Using multivariate analysis, we found positive multiple correlation (R=0.614; F(2.14)=4.236; p<0.036) between the amount of wildfires, solar activity and leukemia rate 2 years before and 3 years after the birth of the subjects under study. Results of the analysis confirmed published information on leukemogenic potency of the woodsmoke in the prenatal ontogenesis, the results allowed the authors to specify timeframe of the dangerous period. The authors suggested that detected linear relationship between solar activity and leukemia rate among young children at 0-4 years was associated with effects of solar activity on the intensity of magnetic fields, risk factors for leukemia. Wild fires affected the intensity of magnetic fields, as well as caused emission of natural radionuclides from the soil to the atmosphere; radioactive pollutants are risk factors cancer. To reduce the risk for childhood leukemia future parents should begin taking vitamins 1-2 years before the planned conception, mothers should take vitamins during pregnancy and lactation. Prolong breast feeding and taking transfer factor for immune recovery.