1998/99 national survey of pesticides in grdundwater using GCMS and ELISA
Notice bibliographique
Résumé
Abstract A total of 95 wells throughout New Zealand were sampled during summer 1998/99 and analysed for a range of pesticides using gas chroma‐tography‐mass spectroscopy (GCMS). Thirty‐three wells (35%) had pesticides including triazine metabolites detected, with 18 wells (19%) having two or more pesticides detected. Only one well (K38/ 0172) had pesticides detected at levels greater than the maximum acceptable value (MAV) for drinking water. There were 20 different pesticides detected, usually at very low concentrations, as well as two triazine metabolites. Fifty‐seven out of the 75 pesticide detections (76%) belonged to the triazine group, with only five of these (9%) being >1 mg m −3 and 74% of these being <0.1 mg m‐ 3 . Three of the 18 non‐triazine pesticide detections (17%) were > 1 mg m −3 with all three detections being in Well K38/ 0172. About half (44%) of the non‐triazine pesticides were <0.1 mg M −3 . Apart from Well K38/0172, the highest levels of pesticides with respect to the MAV were seen for simazine and terbuthylazine, which were 16 and 44% of the MAV, respectively, with the remaining pesticides all below 4% of their MAV. This indicates that, although there were very low levels of pesticides present in 35% of the wells, there would be no significant health risk based on the pesticides analysed from drinking the groundwater investigated with the exception of Well K38/0172. There was a significant decrease in the detection limits for many pesticides for the 1998/99 survey compared to the two earlier surveys. When the detection limits for the earlier surveys were applied to the present survey there would have been a total of 10 wells out of the 95 sampled (11%) with pesticides detected. This compared with 7% of the 82 wells in 1990 and 13.6% of the 116 wells in 1994 with detectable pesticides, indicating that a similar percentage of wells have had detectable pesticides in each survey once correction for variable detection limits has been made. There was a significant difference between wells with and without pesticide detections for the following factors: wells with pesticide detections had shallower well screens, were screened nearer the water table, had lower pH values and higher nitrate levels. Samples for analysis using two enzyme‐linked immunosorbent assay (ELISA) atrazine test kits were collected at the same time as the other pesticide samples. The “normal” atrazine ELISA test kit only showed four positive detections, mainly because of a relatively high detection limit. The high sensitivity (HS) atrazine test kits detected pesticides in 20 of the 28 samples that were tested. Nineteen of the 20 detections had pesticide detections using GCMS, with the other eight samples having no pesticides detected using GCMS. The HS atrazine ELISA test kit appears to be a useful indicator of pesticide contamination for New Zealand groundwater systems at a relatively low level of detection. All the positive GCMS results that were tested gave positive test kit results and there was only one potential false positive result. This is probably because the majority of pesticides detected in groundwater in New Zealand are triazines, and the HS atrazine kit has cross reactivity with most triazines and related pesticides.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,001 | 0,001 |
| Méta-épidémiologie (sens strict) | 0,001 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,002 | 0,002 |
| Études des sciences et des technologies | 0,001 | 0,001 |
| Communication savante | 0,001 | 0,000 |
| Science ouverte | 0,001 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,002 | 0,001 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».