Presence of nonylphenol ethoxylate surfactants in a watershed in central Mexico and removal from domestic sewage in a treatment wetland
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
The Texcoco River in central Mexico is polluted with domestic wastewater as a result of discharges of untreated or inadequately treated sewage. Since nonylphenol ethoxylate (NPEO) surfactants and their intermediate degradation products such as nonylphenol (NP) and NP mono- and diethoxylate (NP1EO, NP2EO) have been found in domestic wastewater and in surface waters near wastewater discharges in industrialized countries, the Texcoco River was sampled to determine whether these compounds were present. The results indicated that NPEOs were present at very high concentrations (> 100 microg/L) in the lower reaches of the Texcoco River, but unlike rivers in industrialized countries, relatively low concentrations of intermediate degradation products, including NP1EO, NP2EO, and NP, were present. The presence and fate of NPEOs compounds in wastewater treatment plants have been studied only in conventional treatment systems in industrialized countries. In this study, the fate of these compounds was studied in a pilot-scale treatment wetland constructed in the small community of Santa Maria Nativitas in the Texcoco River watershed. The treatment wetland removed > 75% of NPEOs from the domestic wastewater, but the greatest proportion of removal occurred in parts of the treatment wetland where sedimentation existed. This is the first report of NPEO compounds in the water resources of a developing country. These data indicate that construction of low-cost and technologically simple treatment wetlands may be one solution to reducing the impacts of contaminants from domestic sewage in developing countries, such as Mexico.
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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 | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 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 it