By Brian Berkenstock

To bleach some ugly stains out of her son's sippy cup, Kim Harrison poured a drop of bleach into the cup and a splash of dishwashing liquid, then she filled the cup with water, swished it around and placed it in her sink, well out of little Conner's reach — or so she thought.

Later that day Harrison got a frantic call at work from her mom, who was watching Conner. He had managed to stretch his arm up over the sink to grab the cup.

Fortunately for the Harrisons, the taste of the brew kept Conner from swallowing much of the solution. (Their local poison control center said the dishwashing liquid would likely give him a stomachache, which it did, but other than that, he'd be OK, which he was.) Unfortunately for other families, not all unsafe substances announce their danger with a bitter taste — and even when they do, kids still manage to swallow some really awful stuff.

Susan Baker, a professor in Health Policy and Management and Environmental Health Sciences at Johns Hopkins School of Public Health, is a pioneer in the field of injury prevention. Her work showing the dangers of adults holding children in their laps while riding in cars led to the passage of child-restraint laws in many states.

She sees the greatest threat in the sheer number of potentially lethal materials that children can contact throughout the home.

"There is less emphasis today on childproof containers, partly because adults have had a hard time getting them open," Baker says. "I hope the emphasis in the future is on finding ways to make products open more easily for adults, rather than suggesting that adults buy products in non-childproof containers." This is especially important for medicines and drugs, which cause the majority of deaths in children less than 5 years old.