11 research outputs found

    Treatment of biomass. A process for the treatment of biomass comprising subjecting biomass to microbial digestion to produce volatile fatty acids and/or solvents followed by wet oxidation to reduce biosolid volume while retaining or increasing the concent

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    A process for the treatment of biomass comprising subjecting biomass to microbial digestion to produce volatile fatty acids and/or solvents followed by wet oxidation to reduce biosolid volume while retaining or increasing the concentration of the volatile fatty acids and/or solvent

    Lack of Estrogenic and Endocrine Disrupting Effects in Juvenile Rainbow Trout Exposed to a New Zealand Pulp and Paper Mill Effluent

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    Previous studies have noted effects of pulp and paper effluents on the physiology of fishes including; smaller gonads, increased age to maturation, alterations in secondary sex characteristics, reduced plasma sex steroid levels, and the induction of vitellogenin (Vtg) in males and juveniles. A program to determine the potential impacts of a modem New Zealand pulp and paper mill effluent on fishes employed a combination of long- and short-term exposures of the juvenile (1+) rainbow trout, Oncorhynchus mykiss, to the effluent. Juvenile (1 + aged) rainbow trout were exposed to a mixed thermomechanical pulp/bleached kraft (TMP/BK) mill effluent at a range of concentrations from environmentally relevant (10%) to 70% (effluent by volume) in three exposure studies. During 21-,56- and 320-day exposures to 10% and 30% (v/v) effluent, no significant impacts on circulating testosterone, and pregnenolone levels were observed. No significant induction of liver MFO activity was observed at any exposure concentration. Vitellogenin induction or expression of the estrogen receptor in juvenile males was not observed in fish from either experiment. High experimental mortality was observed in fish exposed to 70% (v/v) secondary treated effluent compared to a reference treatment during the 2l-d exposure and was linked to an atypically high suspended solids load. Thus, the combined data from these experiments demonstrated a lack of estrogenicity or impacts on steroidogenesis following exposure to TMP/BK mill effluent. However, a parallel experiment using sexually mature rainbow trout did show elevated Vtg in males. Thus, the presence of estrogenic compounds cannot be ruled out, but appears to be infrequent. Results from parallel studies with mosquitofish have shown androgenic activity in the effluent under investigation

    In vivo and in vitro assessment of the androgenic potential of a pulp and paper mill effluent

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    The androgenic potential of a New Zealand pulp and paper mill effluent was measured by applying a combination of in vitro and in vivo bioassays with mosquitofish (Gambusia affinis) and goldfish (Carassius auratus). The in vivo method assessed the rate of gonopodial development (masculinization) and alterations from normal reproductive behavior in adult female mosquitofish exposed for 21 d to untreated or secondary-treated pulp mill effluent. A second in vivo mosquitofish exposure tested the effect of glass-fiber (type C) filtration of secondary-treated effluent on rates of expression of the same endpoints. Extractable organics analyses of effluents and extracts thereof were conducted. Mosquitofish demonstrated significant masculinization on exposure to either treated or untreated effluent; the frequency of gonopodial development was reduced with effluent secondary-treatment. Male mating behavior was observed in the masculinized adult females. Glass-fiber (type F) filtration of the treated effluent eliminated the masculinizing effect, suggesting that the bioactive compounds were associated with the suspended solids. The in vitro method measured the binding of compounds within a treated thermomechanical/bleached kraft effluent extract to androgen receptors contained in goldfish testis cytosol. Exposure to extracts of either the particulate (glass-fiber filtered) or the dissolved organic fraction of the effluent produced significant binding (as indicated by the displacement of radiolabeled testosterone) to the androgen receptor in goldfish gonadal tissue. Thus, the dissolved organics extract of the treated effluent contained compounds androgenic to goldfish in vitro but not to mosquitofish in vivo. The combined in vitro and in vivo data suggest that the effluent in question could exert effects on the reproductive physiology of fishes through an androgenic mechanism. The androgenic compounds androstenedione and testosterone were not detected in the extracts used for the in vitro component of this study

    In vivo and in vitro assessment of the androgenic potential of a pulp and paper mill effluent

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    The androgenic potential of a New Zealand pulp and paper mill effluent was measured by applying a combination of in vitro and in vivo bioassays with mosquitofish (Gambusia affinis) and goldfish (Carassius auratus). The in vivo method assessed the rate of gonopodial development (masculinization) and alterations from normal reproductive behavior in adult female mosquitofish exposed for 21 d to untreated or secondary-treated pulp mill effluent. A second in vivo mosquitofish exposure tested the effect of glass-fiber (type C) filtration of secondary-treated effluent on rates of expression of the same endpoints. Extractable organics analyses of effluents and extracts thereof were conducted. Mosquitofish demonstrated significant masculinization on exposure to either treated or untreated effluent; the frequency of gonopodial development was reduced with effluent secondary-treatment. Male mating behavior was observed in the masculinized adult females. Glass-fiber (type F) filtration of the treated effluent eliminated the masculinizing effect, suggesting that the bioactive compounds were associated with the suspended solids. The in vitro method measured the binding of compounds within a treated thermomechanical/bleached kraft effluent extract to androgen receptors contained in goldfish testis cytosol. Exposure to extracts of either the particulate (glass-fiber filtered) or the dissolved organic fraction of the effluent produced significant binding (as indicated by the displacement of radiolabeled testosterone) to the androgen receptor in goldfish gonadal tissue. Thus, the dissolved organics extract of the treated effluent contained compounds androgenic to goldfish in vitro but not to mosquitofish in vivo. The combined in vitro and in vivo data suggest that the effluent in question could exert effects on the reproductive physiology of fishes through an androgenic mechanism. The androgenic compounds androstenedione and testosterone were not detected in the extracts used for the in vitro component of this study.LR: 20061115; PUBM: Print; JID: 8308958; 0 (Androgens); 0 (Industrial Waste); 0 (Receptors, Androgen); 0 (Water Pollutants, Chemical); ppublishSource type: Electronic(1
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