Survey of bisphenol A in bottled water products in Canada
Bibliographic record
Abstract
A method based on isotope dilution headspace solid-phase microextraction and gas chromatography/mass spectrometry was used to assess levels of bisphenol A (BPA) in 56 samples of bottled water products sold in Canada. Levels of BPA in samples of all 51 non-polycarbonate (PC) bottled water products were lower than the method detection limit (0.50 µg l(-1)). Levels of BPA in most bottled water products in PC carboys were low, ranging from <0.50 to 1.4 µg l(-1) with an average of 0.75 µg l(-1). However, BPA was detected at levels of 8.8 and 6.5 µg l(-1) in two bottles of the bottled water products in PC carboys from the same product analysed over a 5-week period, likely due to accidental or careless exposure of the products to heat (e.g. under the sun) during storage and/or transportation for extended periods of time.
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 | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.003 | 0.003 |
| Science and technology studies | 0.002 | 0.001 |
| Scholarly communication | 0.001 | 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 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".