Feminization in common terns (Sterna hirunda) : relationship to persistent organic contaminants
Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution January 1998 Concern about skewed sex ratios and female-female pairings among endangered roseate terns (Sterna dougall...
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Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
1998
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ftwhoas:oai:darchive.mblwhoilibrary.org:1912/5150 2023-05-15T15:44:38+02:00 Feminization in common terns (Sterna hirunda) : relationship to persistent organic contaminants Hart, Constance A. Bird Island, Buzzards Bay, MA 1998-01 application/pdf https://hdl.handle.net/1912/5150 en_US eng Massachusetts Institute of Technology and Woods Hole Oceanographic Institution WHOI Theses https://hdl.handle.net/1912/5150 doi:10.1575/1912/5150 doi:10.1575/1912/5150 Terns Environmental pollution Thesis 1998 ftwhoas https://doi.org/10.1575/1912/5150 2022-05-28T22:58:34Z Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution January 1998 Concern about skewed sex ratios and female-female pairings among endangered roseate terns (Sterna dougallii) on Bird Island in Buzzards Bay, Massachusetts prompted studies with common terns from the same site as a surrogate species. Over seventy percent (11115) of male common tern embryos sampled from this site in 1993 had testes containing areas of ovarian cortical tissue (ovotestes), suggesting that terns may be affected by endocrine-disrupting contaminants. These terns are exposed to non-ortho PCBs which bind to the aryl hydrocarbon receptor (AhR), and lower chlorinated PCBs, hydroxymetabolites of which bind to the estrogen receptor. Our objectives were to document the presence of ovotestes in common tern embryos from Bird Island and Nauset, a reference site, in 1994, and to determine the relationship between environmental contaminants and ovotestes development, as well as other health-related effects. Pipping tern embryo gonads were examined histologically, and yolk sacs were extracted and analyzed for PCBs and chlorinated pesticides. Extracts also were analyzed for dioxin equivalents (TCDD-EQs) using a chick embryo hepatocyte (CEH) bioassay. Total PCBs were significantly higher in Bird Island tern embryos (mean 114, range 17- 663 ugig lipid) than Nauset (mean 35, range 8- i 78 ugig lipid); but were variable at both sites. Total PCBs were highly correlated with TCDD-EQs. Tern hepatic EROD activity was relatively insensitive to induction; only when TCDD-EQs were above 82 ± 26 ng/g lipid were EROD activities elevated. Levels of organic pesticides were below levels thought to be of toxicological significance. The percentage of male tern embryos with ovotestes at Nauset (60%) and Bird Island (78%) was high and not significantly different; ovotestes in terns from both sites ranged in severity from absent (1) to intersex ... Thesis Bird Island Common tern Woods Hole Scientific Community: WHOAS (Woods Hole Open Access Server) Bird Island ENVELOPE(-38.060,-38.060,-54.004,-54.004) Woods Hole, MA |
institution |
Open Polar |
collection |
Woods Hole Scientific Community: WHOAS (Woods Hole Open Access Server) |
op_collection_id |
ftwhoas |
language |
English |
topic |
Terns Environmental pollution |
spellingShingle |
Terns Environmental pollution Hart, Constance A. Feminization in common terns (Sterna hirunda) : relationship to persistent organic contaminants |
topic_facet |
Terns Environmental pollution |
description |
Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution January 1998 Concern about skewed sex ratios and female-female pairings among endangered roseate terns (Sterna dougallii) on Bird Island in Buzzards Bay, Massachusetts prompted studies with common terns from the same site as a surrogate species. Over seventy percent (11115) of male common tern embryos sampled from this site in 1993 had testes containing areas of ovarian cortical tissue (ovotestes), suggesting that terns may be affected by endocrine-disrupting contaminants. These terns are exposed to non-ortho PCBs which bind to the aryl hydrocarbon receptor (AhR), and lower chlorinated PCBs, hydroxymetabolites of which bind to the estrogen receptor. Our objectives were to document the presence of ovotestes in common tern embryos from Bird Island and Nauset, a reference site, in 1994, and to determine the relationship between environmental contaminants and ovotestes development, as well as other health-related effects. Pipping tern embryo gonads were examined histologically, and yolk sacs were extracted and analyzed for PCBs and chlorinated pesticides. Extracts also were analyzed for dioxin equivalents (TCDD-EQs) using a chick embryo hepatocyte (CEH) bioassay. Total PCBs were significantly higher in Bird Island tern embryos (mean 114, range 17- 663 ugig lipid) than Nauset (mean 35, range 8- i 78 ugig lipid); but were variable at both sites. Total PCBs were highly correlated with TCDD-EQs. Tern hepatic EROD activity was relatively insensitive to induction; only when TCDD-EQs were above 82 ± 26 ng/g lipid were EROD activities elevated. Levels of organic pesticides were below levels thought to be of toxicological significance. The percentage of male tern embryos with ovotestes at Nauset (60%) and Bird Island (78%) was high and not significantly different; ovotestes in terns from both sites ranged in severity from absent (1) to intersex ... |
format |
Thesis |
author |
Hart, Constance A. |
author_facet |
Hart, Constance A. |
author_sort |
Hart, Constance A. |
title |
Feminization in common terns (Sterna hirunda) : relationship to persistent organic contaminants |
title_short |
Feminization in common terns (Sterna hirunda) : relationship to persistent organic contaminants |
title_full |
Feminization in common terns (Sterna hirunda) : relationship to persistent organic contaminants |
title_fullStr |
Feminization in common terns (Sterna hirunda) : relationship to persistent organic contaminants |
title_full_unstemmed |
Feminization in common terns (Sterna hirunda) : relationship to persistent organic contaminants |
title_sort |
feminization in common terns (sterna hirunda) : relationship to persistent organic contaminants |
publisher |
Massachusetts Institute of Technology and Woods Hole Oceanographic Institution |
publishDate |
1998 |
url |
https://hdl.handle.net/1912/5150 |
op_coverage |
Bird Island, Buzzards Bay, MA |
long_lat |
ENVELOPE(-38.060,-38.060,-54.004,-54.004) |
geographic |
Bird Island |
geographic_facet |
Bird Island |
genre |
Bird Island Common tern |
genre_facet |
Bird Island Common tern |
op_source |
doi:10.1575/1912/5150 |
op_relation |
WHOI Theses https://hdl.handle.net/1912/5150 doi:10.1575/1912/5150 |
op_doi |
https://doi.org/10.1575/1912/5150 |
op_publisher_place |
Woods Hole, MA |
_version_ |
1766379018885529600 |