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There may be  a link between childhood leukemia and how much vehicle exhaust a young child is exposed to. The Centers for Disease Control and Prevention reviewed seven previous studies to reach that finding, but cautions more research on direct-cause-and-effect is needed.

The CDC's review found children diagnosed with leukemia were 50% more likely to live near busy roads than children without the blood-borne cancer. It's the most common form of childhood cancer anbd makes up one-third of all cancers in children age 14 and younger.

The review appears in the April issue of the "American Journal of Preventive Medicine." Click here.

[Metro Networks]