Show simple item record

dc.contributor.authorLeusch, Frederic D. L.en
dc.date.accessioned2010-05-31T23:23:16Z
dc.date.issued2004en
dc.identifier.urihttps://hdl.handle.net/10182/1983
dc.description.abstractStudies in Europe, Japan, and North America have reported that wild fish exposed to treated sewage effluents can exhibit significant physiological and reproductive abnormalities consistent with exposure to hormonally active chemicals. The main objective of this research project was to examine the estrogenic and androgenic activity in treated sewage to determine the risk associated with treated sewage discharges in Australia and New Zealand. Several bioassays, including a sheep estrogen receptor and a rainbow trout androgen receptor binding assay, were set up and validated with model compounds. The assays were then used to measure the estrogenic and androgenic activity in sewage samples from 15 municipal sewage treatment plants (STP) utilizing a variety of treatment technologies. Raw sewage samples contained high levels of both estrogenic and androgenic activity, up to 185 ng/L estradiol equivalents (EEq) and up to 9330 ng/L testosterone equivalents (TEq), respectively. Secondary treatment processes such as activated sludge had the greatest impact on removal of biological activity from the wastewater. The estrogenic and androgenic activity in final treated effluents were <1 to 4.2 ng/L EEq and <6.5 to 736 ng/L TEq, respectively. Based on lowest observable effective concentrations reported in the literature, these levels are unlikely to induce biological effects in exposed fish in the short term. To examine potential long-term effects, resident mosquitofish chronically exposed to undiluted treated sewage were sampled. Several morphological biomarkers indicative of endocrine disruption were measured and compared with mosquitofish captured at a reference site. Mosquitofish captured in a constructed wetland for tertiary treatment of secondary treated sewage exhibited morphological differences such as elongated anal fins consistent with exposure to androgenic chemicals, although this effect was not measurable in fish collected at sites further downstream or at any of the other sites. Based on these results, it is unlikely that mosquitofish populations would be significantly affected by exposure to final treated sewage. A reverse transcription real-time polymerase chain reaction (RT-PCR) method to measure the production of a female-specific protein (vitellogenin) mRNA in adult male mosquitofish was developed, and this could be used as a rapid test to detect early changes in individuals exposed to estrogenic activity.en
dc.language.isoenen
dc.publisherLincoln Universityen
dc.subjectactivated sludgeen
dc.subjectandrogen receptor (AR)en
dc.subjectbiomarkersen
dc.subjectsheepen
dc.subjecttrickling filteren
dc.subjectvitellogeninen
dc.subjectestrogen receptor (ER)en
dc.subjectin vitro bioassayen
dc.subjectmosquitofishen
dc.subjectrainbow trouten
dc.subjectreceptor binding assaysen
dc.subjectsewage treatmenten
dc.titleEstrogenic and androgenic potential of municipal sewage in Australia and New Zealanden
dc.typeThesis
thesis.degree.grantorLincoln Universityen
thesis.degree.levelDoctoralen
thesis.degree.nameDoctor of Philosophyen
lu.contributor.unitLincoln Universityen
lu.contributor.unit/LU/AFSCen
pubs.organisational-group/LU
pubs.organisational-group/LU/AFSC
pubs.publication-statusPublisheden
dc.publisher.placeCanterburyen


Files in this item

Default Thumbnail
Default Thumbnail

This item appears in the following Collection(s)

Show simple item record