This directory contains 67 digitized diatom images representing 66 taxa from the Procter and Gamble Experimental Stream Facility near
Cincinnati, OH. See Belanger et al in Aquatic Mesocosm Studies in Ecological Risk Assessment, Ward, C.H., B.T. Walton, and T.W. La Point, Lewis Publishers
for a detailed description of the facility. Water for the artificial streams comes from the Lower East Branch of the Little Miami River in Clermont County. This 5th
order tributary of the Little Miami has been designated as an Exceptional Warmwater Habitat by the Ohio EPA. Most of the water shed (1297 km2) consists of
heavily wooded slopes and zones of riparian vegetation. There are seven populations centers and one dam along its 132 km course. The designed low flow from
the dam is 30 CFS. The ESF has the ability to supply its artificial stream channels with a mixture of stream water, waste water effluent, and product chemicals.
These manipulations serve as multispecies bioassay experiments before commercial introduction of consumer products. These digitized images are from diatoms
collected from tile and cobble substrates through the course of a bioassay testing the effects of lauryl trimethyl ammonium chloride, a proposed detergent surfactant
(see Belanger et al 1993).
We'd like to thank Scott Belanger and The Procter and Gamble Company for permission to make these images available.