contaminate

Many shooters use their baseball caps to collect spent brass; this contaminates the cap with lead particles.

Published studies have found that pollen from genetically engineered canola can contaminate fields more than 1.5 miles away.

How do the salmonella contaminate the rendered byproducts?

Thus, care givers have numerous opportunities to contaminate their hands during routine care, and unless they wash their hands, virus will be transmitted by indirect contact to other infants.

The bacterium is transmitted to humans in part by bovine feces, which can taint water used to irrigate crops and can also contaminate meat through improper food handling during processing.