Sterols as bio-markers for waste impact and source characterization in stream sediment.

Sterols are involved in life processes in organisms and are therefore potential biomarkers for assessment of environmental ecosystems. Current data indicate that sterols are persistent in stream sediments, since sterols are not sufficiently soluble in water to be readily detected in water samples. Stream sediment therefore can act as an integrating exposure index of pollution for animal or human waste in streams.

Quality of Packaged Ice Purchased at Retail Establishments in Iowa.

The quality of packaged ice sold in retail establishments is not uniformly regulated, and its cleanliness and safety have not been recently evaluated. This investigation examined the physical, chemical, and microbiological characteristics of 18 brands of packaged ice purchased at Iowa stores. Twenty-two ice samples were melted under controlled conditions and portions were analyzed for selected analytes established as primary and secondary drinking water standards by the U.