The Story of Environmental Androgens, the Impact of Paper Mills, And Risks

Ronald Jenkins, Mike Howell, John Carson, Paul Blanchard and Virginia Brown

Vulcan Materials Center for Environmental Stewardship and Education and Department of Biology Samford University  

Environmental androgens in biologically effective concentrations were demonstrated more than 20 years ago when a population of the eastern mosquitofish was discovered in which the females were all masculinized. Since then, other populations of masculinized mosquitofish have been discovered living in small coastal streams in Florida that receive paper mill effluent. In recent years we have studied the Fenholloway River which has been described as one of the nation's most polluted rivers and carries discharge from a large paper mill in Perry, Florida. Using androgen receptor transcription (ART) assays to detect and liquid chromatography mass spectrometry (LCMS) to quantify, androstenedione (AED) was measured at 0.14 nM in the water column of the Fenholloway River. Higher concentrations of AED (2.4 nM) and its biosynthetic precursor progesterone (155 nM) were identified in sediment from the Fenholloway. We hypothesized that androgens in paper mill effluent were generated by microbial degradation of the high levels of progesterone from the mill pulp. To test this hypothesis, we conducted three experiments: 1) Wood from a loblolly pine was dried and extracted by HPLC.  Progesterone was detected in the wood by ART and quantified by LCMS to be 46.4 + 4.1 nmoles/gm dry wt.  2) A common soil bacterium, Mycobacterium smegmatis, was incubated with progesterone. Using ART assays and high-pressure liquid chromatography (HPLC) AED and andrastadienedione (ADD) were biotransformed from progesterone over a 20 day period.  3) The sediment of the Fenholloway River was reanalysized using an ART assay, HPLC, and MS which verified appreciable amounts of AED and ADD.  Progesterone is produced and stored in pine wood to high levels which when released to aquatic environments is microbially converted to AED and ADD.  ADD, being an inhibitor of P450 aromatase, may be the more important environmental androgen.