Investigators from the state health department could find no chemical, physical or infectious agent that might explain the outbreak.

Electric and magnetic fields are complex physical agents whose potential health effects are the subject of much research.

Octacosanol has been studied as an exercise- and physical performance-enhancing agent.

Many different substances in the environment may cause urticaria, including medications, food and physical agents.

"Some diseases attack the psyche and cannot be traced to any physical agent."

Units of measure for physical agents such as noise are specific to the agent.

Hazards can be either physical, microbiological, biological or chemical agents of disease.

Amendment No 1 is a reminder that we still do not have the directives concerning the remaining physical agents.

This proposal concerning physical agents is a very real proposal to me.

When people hear that the first proposal concerning physical agents goes right back to 1992, the reactions are very critical.