San Jose Mercury News reporter Chris O'Brien was skeptical of the link between mobile phones and brain tumors. Then he talked to a Harvard professor, and started reading — not just research, but his frighteningly cautious BlackBerry manual.

O'Brien, like most consumers, had ignored the safety disclosure that came with his BlackBerry Curve. It turns out it read, "Keep the device at least 0.98 inches (25 mm) away from your body when the BlackBerry device is turned on and connected to a wireless network." Visiting Harvard epidemiologist Devra Davis told him, "you don't want to hold a small microwave radio next to your head." So check your manual. A ten-year study on cell phones and tumors by the World Health Organization was inconclusive but reported "some indications of an increased [tumor] risk... for those who reported the highest 10 percent of cumulative hours of cell phone use." You don't want to end up sick and be told, "you were holding it wrong."

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