Determination of the androgenic potency of whole effluents using mosquitofish and trout bioassays

Altered reproduction in fish exposed to pulp and paper mill effluents: Roles of individual compounds and mill operating conditions

“…Further studies have highlighted the possibility that phytosterols can be converted to progesterone, and then to androstenedione and androstadienedione, by microbial populations in the water and sediment downstream from mills [41]. Recent work from New Zealand, however, has shown that relatively high waterborne concentrations (10‐100 μg/L) of androstenedione and androstadienedione are required to elicit masculinization in mosquito fish [59]. This is consistent with other evidence from New Zealand that sterols present in effluents, as well as theirb oxidation products resulting from chlorine dioxide bleaching, are not involved in the masculinization of mosquito fish and did not show activity in rainbow trout brain androgen receptor– binding assays.…”

Altered development and reproduction in western mosquitofish (Gambusia affinis) found in the Hanxi River, southern China

“…The development and reproductive health of PPME-exposed Fenholloway River mosquitofish were found to be altered by comparison with mosquitofish living in the Econfina River in Florida, USA [18]. With the exception of PPME, few reports have been published thus far on masculinization phenomena in fish exposed to municipal effluents or living downstream from sewage treatment plants [28].…”

Naturally occurring progesterone in loblolly pine (Pinus taeda L.): A major steroid precursor of environmental androgens

“…The relative locations of the effluent and control collection sites are shown in Figure 5. The presence of androstenedione in the Fenholloway River was later confirmed [15], and its role as an active environmental androgen precursor is consistent with the absence of androstenedione in water from another river where the resident female mosquitofish population is phenotypically normal [16].…”

“…27, 2008 J.D. Carson et al later confirmed [15], and its role as an active environmental androgen precursor is consistent with the absence of androstenedione in water from another river where the resident female mosquitofish population is phenotypically normal [16]. The ability of phytosteroids, such as ␤-sitosterol from pine tree bark, to alter the reproductive endocrine status of goldfish [17] and data correlating the presence of androstenedione with abnormal masculinization of mosquitofish [7,9] were consistent with the hypothesis that phytosteroids serve as the primary precursors for microbes to produce progesterone and the biologically active androgens [9].…”