Risks for developing childhood leukemia are increased by <"http://www.yourlawyer.com/topics/overview/CT-Scan-Radiation-Overdose">diagnostic X-rays, said Science Daily, citing a study by researchers at the University of California, Berkeley’s School of Public Health. An issue, given that, as weâ€™ve previously noted, the average child will undergo seven radiation scans by they time he/she reaches age 18.
The team found that children with acute lymphoid leukemia (ALL) experienced a nearly two-fold risk from exposure to no less than three X-rays, versus children not diagnosed with leukemia, said Science Daily. And, for those children with B-cell ALL, the risk was seen with even one X-ray, with â€œmodestâ€ risks linked with chest X-rays, added Science Daily. The findings appeared in the October 2010 issue of the International Journal of Epidemiology and originated from the Northern California Childhood Leukemia Study, which is a population-based case-control study that included 35 counties in Californiaâ€™s northern and central regions.
Acute lymphoid leukemia is the most common type of cancer among kids aged 1 to 7 years. While it is often treated successfully, it can be fatal. Leukemia is a cancer of the white blood cells and is, said the American Cancer Society, the most common childhood cancer, comprising about one-third of all cancers in children under 15 years.
Long known is the connection between high radiation doses and cancer, said Science Daily; however, there is some controversy concerning how low radiation dosesâ€”seen in conventional X-rays or radiographsâ€”can affect human health.
“The general clinical impression has been that the level of radiation a child would be exposed to today from a conventional X-ray would not confer an additional risk for cancer,” said Patricia Buffler, UC Berkeley professor of epidemiology and principal investigator of the Northern California Childhood Leukemia Study. “The results of our study were not what we expected,” quoted Science Daily.
The study looked at 827 children diagnosed with either ALL or AML; these children were compared to other children who were selected at random from the California birth registry and who were matched to age, gender, ethnicity, and maternal race, said Science Daily.
The research revealed an increased risk for ALL from X-rays; the risk was not present for AML or T-cell leukemia, with age at initial exposure, or with prenatal exposure to X-rays or maternal X-rays prior to pregnancy, but these exposures were also not the norm in this particular population, noted Science Daily.
“X-rays are a valuable tool, and our findings indicate that their use should continue to be judicious,” said Karen Bartley, doctoral student in epidemiology and first author of the study, quoted Science Daily. “Of greater concern, perhaps, is the use of newer imaging technologies, which are becoming more common and which produce far higher doses of radiation,” Bartley added.
“The findings about increased leukemia risk certainly warrant further investigation,” said UC San Francisco radiologist Dr. Rebecca Smith-Bindman, who was not part of the X-ray study, reported Science Daily. “If even plain film X-rays are associated with an increased risk of leukemia, then one has to wonder about CT scans, some of which can generate 500 times the dose of radiation of an X-ray.”
We previously wrote that initial study authors called their findings a â€œvery serious alert,â€ and urged that doctors avoid unnecessary X-rays for children, and take precautions with CT scans, which create more radiation than traditional X-rays.