Long-term trends in legacy contaminants in aquatic wildlife in the Hamilton Harbour Area of Concern
Bibliographic record
Abstract
Long-term trends in contaminant exposure were examined in eggs of two aquatic-feeding species, the Herring Gull (Larus argentatus) and the Snapping Turtle (Chelydra serpentina), collected from locations within the Hamilton Harbour Area of Concern, an industrialized area historically associated with high concentrations of legacy persistent organic pollutants, metals and other compounds. Significant declines in concentrations of sum polychlorinated biphenyls, four organochlorine pesticides and 2,3,7,8-tetrachlorodibenzo-p-dioxin were evident in Herring Gull eggs collected from nesting colonies within the harbour (range in % declines = 86%–94%) and in Snapping Turtle eggs from two area of concern wetland/creek locations (range in % declines = 36%–89%) from the 1980s to 2012. Temporal trends in polychlorinated biphenyl congener profiles in eggs were examined by grouping polychlorinated biphenyl congeners according to structure-activity relationships based on their susceptibility to be metabolized by the cytochrome P450 system. Significant temporal changes in the percentages of non-metabolizable congeners (i.e. increase) and congeners metabolized by P450 1A enzymes (i.e. decrease) were evident in eggs of both species. It is not clear if these distinct temporal patterns are related to changes in metabolism following reductions in polychlorinated biphenyl burdens or changes in bioavailability of congeners in the environment. Large decreases in contaminant burdens in eggs of these two species at two different geographic scales within the area of concern (i.e. local scale for Turtles and regional scale for Gulls) are reflective of improved environmental conditions within the harbour and support their utility as top-predator wildlife bio-indicator species.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.002 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".