Establishing a baseline value for urinary arsenic:selenium ratio in unexposed populations in the United Kingdom
Notice bibliographique
Résumé
The relationship between arsenic (As) and selenium (Se) in the human body is poorly understood. We have investigated the concentrations of urinary As and Se in three ethnic groups (n=63) in the United Kingdom and show that there is a positive correlation (r=0.62, p<0.001) between total concentrations of As and Se and that the ratio of these two elements is stable, with a mean value (±SD) of 0.7±0.4. Furthermore, concentrations of individual arsenic species methylarsonate (MA), dimethylarsinate (DMA) and arsenobetaine (AB) in the urine samples show a positive correlation with total Se (As(III) and As(V) were not detected). The intra-individual variation of the As:Se ratio also remains stable over time, as determined by monitoring a volunteer over a period of one year, and deviates only after recent seafood consumption. It appears that the ratio is also stable across diverse populations across different cultures and continents, evident from our calculation of As:Se ratio from concentrations of these elements found in urine samples from different populations published in the literature. Our study involved analysis of 63 urine samples from three ethnic groups (White Caucasian n=20, Asian n=21 and Somali n=22), 58 urine samples from 29 Ramadan fasting volunteers and 12 from one volunteer whose urine samples were collected over a period of one year. All the participants completed a lifestyle questionnaire and were asked to refrain from eating seafood or fish for three days prior to collection of the sample. Total As and Se in urine were determined by inductively coupled plasma mass spectrometry (ICP-MS). As species (AB, DMA, MA, As(III), As(V)) were determined by using high performance liquid chromatography (HPLC) combined with ICP-MS. Mean ± SD As:Se ratios of 0.8±0.4, 0.7±0.4, 0.4±0.2, 0.7±0.3 and 1.2±0.3 were obtained for the Asian, White Caucasian, Somali, fasting, and one volunteer respectively, giving an overall mean of 0.7±0.4 (SD). It is noteworthy, that when comparing ethnic differences, the Somali group shows a statistically significant lower As:Se ratio (0.4±0.2, p<0.05) compared to Asian and White Caucasian groups; this is ascribed to lower urinary As concentrations in this group. The study over one year with a single volunteer revealed that recent (within 3 days) seafood consumption results in a significantly different (p<0.05) As:Se ratio (4.0). We have calculated from the literature the value of As:Se for populations, exposed to As through drinking water, can range from 2.0–9.6. Based on our own work and the values we calculated from other studies we suggest that the baseline range for mean As:Se ratio is 0.4–1.2, provided that the urine samples are collected in the absence of recent consumption of seafood. The relatively stable As:Se ratio observed in this study suggests a link between these two elements in humans adding support to earlier studies with animals and humans exposed to inorganic arsenic in drinking water which reported interaction between these elements and that Se may play a role in counteracting As toxicity.
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 | 0,004 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,001 | 0,000 |
| Bibliométrie | 0,001 | 0,001 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,001 | 0,000 |
| Science ouverte | 0,000 | 0,001 |
| Intégrité de la recherche | 0,001 | 0,000 |
| 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 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 ».