Disinfection By-Products (DBPs) in Drinking Water from Eight Systems Using Chlorine Dioxide
Notice bibliographique
Résumé
Abstract A study was initiated to determine the presence of organic disinfection by-products (DBPs) in drinking water treated with chlorine dioxide (ClO2). One potential advantage for the use of ClO2 as a disinfectant is the reduced formation of organic DBPs. Generally, water treated with ClO2 produces chlorite and chlorate ions, but there is limited information regarding the presence of halogenated organic DBPs. Eight systems that use chlorine dioxide as part of the water disinfection process were investigated. All systems in this study applied chlorine as a primary or secondary disinfectant in addition to ClO2. To evaluate seasonal and spatial variations, water samples were collected during cold water (February to March 2003) and warm water (July to August 2003) months at five sites for each system: raw water (R, before treatment), treated water (T, after treatment but before distribution), and three points along the same distribution line (D1, D2, D3). Sampling and analysis were conducted according to established protocols. A suite of 27 organic DBPs including haloacetic acids (HAA), trihalomethanes (THM), haloacetonitriles (HAN), haloketones, haloacetaldehydes (HA), chloropicrin, and cyanogen chloride were examined. In addition, the concentration of oxyhalides (chlorite and chlorate ions) and auxiliary parameters were also determined. Chlorite was found in treated (T) and distributed (Dx) waters. The chlorite ion levels decreased along the distribution system (T > D1 > D2 > D3). At T sites, the levels ranged from 10 to 870 µg/L (winter), and from 300 to 1,600 µg/L (summer). Chlorite was not found in treated or distributed water in the one system that used ozone. Chlorate ion levels ranged from 20 to 310 µg/L (winter), and 80 to 318 µg/L (summer). Chlorate levels remained relatively constant throughout the distribution system. THM and eight HAA (HAA8) accounted for approximately 85% of the total DBPs (wt/wt) analyzed, followed by total HA (up to 7%) and HAN (3%). THM in distributed water were found at concentrations between 1.8 and 30.6 µg/L (winter), and 3.3 and 93.6 µg/L (summer). For HAA8, the levels ranged from 13 to 52 µg/L (winter), and 16 to 111 µg/L (summer). Chloral hydrate ranged from 0.2 to 5.2 µg/L (winter), and 0.4 to 12.2 µg/L (summer). The temporal and spatial variations observed in previous studies were confirmed in the current study as well.
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 distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,003 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,001 | 0,000 |
| Communication savante | 0,000 | 0,001 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,001 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,001 | 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 tête enseignante, 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 ».