Radiation used in CT scans may be harmful to the genetic material within mummified remains.

VOA: special.2010.06.29

The experts also noted that taking too much of some vitamins can be harmful.

VOA: special.2009.04.21

People should ask a health expert about drug combinations that could be harmful.

VOA: special.2009.07.21

People should ask a health professional about drug combinations that could be harmful.

VOA: special.2009.07.08

At least two hundred fifty of them are known to be harmful.

VOA: special.2010.03.09

But too much stress can be harmful.

VOA: special.2009.03.24

Spokesperson David Epstein says the ash,which is drifting at an altitude of almost 10 kilometers, could be harmful when it hits the ground.

VOA: standard.2010.04.16

Iron is a vital nutrient, but too much iron can be harmful.

VOA: standard.2010.08.05

"It could be taken up by crustaceans like shrimp crabs, things like that which are the base of the food chain and that could be passed up to fish and then mammals and the toxins could be concentrated and that could be harmful to animals that feed on these smaller organisms."

VOA: standard.2010.05.09

So it can be seen as having no harmful effects on the environment.

VOA: special.2009.10.05