No association was found if the exposure occurred in the second half.

It is difficult to tell from these tests when the exposure may have occurred.

"We are making no assumptions as to where this exposure occurred."

What you were doing when the exposure may have occurred (hiking, for example).

Exposure can occur through air, water, soil, and consumer products.

For most people, exposure to mercury occurs only by accident.

The hypothesis was that this exposure would occur before birth.

Pellow's first exposure to music occurred around the age of 7.

These recommendations do not address instances where a known exposure has occurred.

Human exposure occurs through food consumption or ground and surface water contamination.