Soil quality guidelines for dioxins and furans in Canada: A review and international comparison
Bibliographic record
Abstract
Polychlorinated dibenzo-para-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) (collectively PCDD/Fs) are toxic and persistent contaminants produced as unintentional by-products of anthropogenic activities. Human exposure to PCDD/Fs occurs primarily through consumption of contaminated food, though point-source soil contamination can also meaningfully contribute to exposure. Environmental soil quality guidelines (ESQGs) for PCDD/Fs have been developed worldwide. In Canada, the 2002 federal ESQG of 4 ng/kg has been adopted by most provinces and is based on limited background soil data. In the remaining provinces, ESQGs derived to be protective of human health range from 15 ng/kg to 95 ng/kg. Internationally, 70% of human health protective ESQGs adopted since 2010 range from 20 ng/kg to 120 ng/kg. Considering the consistency in human health protective ESQGs observed worldwide, the ongoing inputs of PCDD/Fs to the environment and the evolving scientific understanding of PCDD/F toxicity over the last two decades, the federal ESQG appears outdated. As ESQGs are of specific importance in the management of contaminated sites, they must remain protective of human health without being unreasonably cautious. Federal agency review and update of the ESQG for PCDD/Fs appears warranted and should consider the establishment of a risk-based guideline protective of human health.
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 machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.008 | 0.011 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.002 | 0.001 |
| Bibliometrics | 0.015 | 0.025 |
| Science and technology studies | 0.001 | 0.002 |
| Scholarly communication | 0.002 | 0.001 |
| Open science | 0.003 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.002 | 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 source (direct Gemma or distilled Codex), 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".