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This study compared the use of sentinel species- and community-based field approaches for assessing the biological status of fish living in a river receiving pulp and paper mill effluents. Three approaches were compared. Two approaches used sentinel species. One of these involved an internal/external examination of the fish that leads to the calculation of a fish health assessment index (HAI) and the other involved biochemical measurements of hepatic mixed function oxidase (MFO) activity and plasma steroid levels. The third approach characterized the fish community structure according to an index of biotic integrity (IBI). The comparison focused on how the methods respond to the hypothesis that recent process modifications/effluent treatment changes, resulting in demonstrable improvements in effluent quality, have beneficial effects on fish. Neither of the approaches using sentinel fish indicated clear mill-related influences either before or after the process modifications/effluent treatment changes. There was no evidence of depressed plasma steroids and increased MFO activity in fish frequently associated with mill effluent exposure in previous studies. While the HAI was higher at stations downstream from two mills, this could not be linked to effluent exposure alone. In contrast, the study of community structure showed a substantial improvement in fish assemblages at all the mill sites.

Three new peptides with high steroidogenic activity in vivo have been isolated from porcine pituitary extracts. Similar in molecular weight to porcine ACTH, they differ from the usual amino acid composition in molar ratios of aspartic acid, threonine, serine, glycine, valine, methionine and phenylalanine.

A wide range of Δ 4 - and Δ 1 , 4 -3-ketosteroids, from weakly polar to strongly polar, may be chromatographed and detected on cellulose triaacetate paper, with benzene—methanol—water mixtures as developing solvents. Three systems have been worked out. In the first a one-phase mixture of benzene, methanol and water is used as the mobile phase and the paper is not accommodated. A “reversed phase” type of chromatogram is obtained, i.e. the more polar compounds have higher R F values than the less polar ones, as is usual for chromatography on acetylated paper. If, howerver, two-phase mixtures of benzene, methanol and water are used, as was the case in the other two methods, “reversed phases”, as well as “convetional” type chomatograms may be obtained. This depeds upon whether the lower or the upper layer is used as the mobile phase, the other layer being used for accommodation of the paper. Perhaps the first-mentioned method should, in contrast to the other two, be regarded as adsorption chromatography, rather than as partition chromatography. Well-reproducible R F values are obtained and, especially with the two-phase mixtures, compact spots are found. Detection methods and R F dta are given for various Δ 4 - and Δ 1 , 4 -3- ketosteroids, ranging from C 18 to C 27 compounds and including sex hormones and adrenoccortical hormones.