Heavy metals in soil on spoil heap of an abandoned lead ore treatment plant, SE Congo-Brazzaville

Total concentrations of 4 heavy metals (Pb, Zn, Cu, and Mn), non-metal As and three reference elements (Ti, Fe and Al) of a soil profile on spoil heap were examined. 54 soil samples were collected in the soil profile at different depths: 15 to 45, 45 to 75, 75 to 105, 105 to 135 and 135 to 150 cm. The first 15 cm of top layer contained an accumulation of ores and was not sampled. Lead, zinc, copper, manganese and arsenic levels in the soil profile decreased from 11800 to 2000, 2400 to 1200, 270 to 90, 6700 to 750 and 1300 to 600 mg/kg, respectively. The levels of these trace elements were higher than the permissible limit level in soil according to European norms. The concentration levels of heavy metals and arsenic in the soil profile are listed in the following order: Pb > Mn > Zn > As > Cu. High positive correlations were observed between As, Cu, Zn and Al, Fe, Mn, Ti. Among the heavy metals, lead was not significantly correlated with Al, Fe and Ti. Evaluation of enrichment factor, geo-accumulation index and pollution load index values from the measured concentrations of heavy metals and continental crust values shows a very high contamination of the soil profile by the heavy metals studied and arsenic.Key words: Heavy metals, spoil heap, contamination, enrichment factor, geo-accumulation index, pollution load index

Evaluation hydro-chimique des eaux souterraines en milieu urbain au Sud-Ouest de Brazzaville, Congo

La qualité physico-chimique des eaux souterraines au sud-ouest de Brazzaville a été évaluée pour l’usage eau de boisson. Les eaux de 27 puits et 1 source ont été prélevées entre mars et avril 2007 (saison des pluies) puis analysées. 16 paramètres ont été déterminés dans les échantillons d’eau: pH, conductivité électrique (C.E), solides totaux dissous (TDS), Ca2+, Mg2+, K+, Cl-, SO4 2-, NO3 -, THt (dureté totale), TAC (titre alcalimétrique complet), fluorure (F -), ortho phosphate (PO4 3-), fer total (Fetot), manganèse total (Mntot), chrome (Cr(VI)). L’application des méthodes exploratoires multivariées (analyse factorielle et classification ascendante hiérarchique) a permis, respectivement : (i) d’identifier les paramètres les plus pertinents qui décrivent la qualité de ces eaux souterraines ; (ii) de montrer leur variabilité spatiale; (iii) de réduire le nombre de points de prélèvements d’eaux (puits et source) en groupes homogènes dans le cadre d’une étude possible du suivi temporel et spatiale de la qualité de ces eaux souterraines. Le pH variait entre 3,85 et 6,08, ce qui montre un caractère acide. 28,57% des eaux analysées avaient une conductivité électrique comprise entre 300 μS/cm et 431μS/cm. Les autres soit 71,43%, faiblement minéralisées avaient une conductivité inférieure à 300 μS/cm. Une corrélation significative a été observée entre la conductivité électrique (C.E) et d’autres paramètres (TDS, Ca2+, Cl-, SO4 2-, PO4 3-, Cr(VI), Mntot) exceptés Mg2+ et K+. Lesconcentrations en ions majeurs (Ca2+, Mg2+, K+, Cl-, SO4 2-) étaient toutes inférieures à la valeur guide O.M.S respective. Ces eaux sont douces et d’une faible alcalinité essentiellement due aux ions bicarbonates (HCO3 -). Le paramètre le plus déclassant pour l’usage eau de boisson a été le chrome VI pour lequel 78,57% des points d’eaux analysées (y compris la source) avaient une teneur supérieure à 0,05 mg/L.Mots-clés : Eaux souterraines, chrome VI, analyses exploratoires multivariées, Brazzaville Congo

Assessment of Groundwater Quality in Central India

Abstract The groundwater is widely used for irrigation of rice crops. The overuse of groundwater causes depletion of the water quality (i.e. enormous increase in conductivity, hardness and ion and metal contents, etc.) in several regions of the country and world. In this work, the quality of the groundwater in the densestrice cropping area, Saraipali, Chhattisgarh, Central India is discussed. The water is sodic in nature with extremely high electrical conductivity. The mean concentration (n = 15, 56 ± 9, 19 ± 4, 206 ± 25, 9.2 ± 2.3, 39 ± 6, 114 ± 19 and 1.7 ± 0.6 mg/L, respectively. The sources of the contaminants are apportioned by using the factor analysis model. The suitability of the groundwater for the drinking and irrigation purposes is assessed

A qualitative study of patients' experience of living with inflammatory bowel disease: A preliminary focus on the notion of adaptation.

This study investigates the lived experience of inflammatory bowel disease with the aim of examining the process of adapting to life with inflammatory bowel disease. Adaptation is often referred to as the desirable outcome in chronic illnesses such as inflammatory bowel disease; yet little is known as to how this is achieved. A total of 10 Crohn's and 12 ulcerative colitis patients recruited from online support networks participated in individual, semi-structured interviews. The study has identified the notion of a 'new normal' as central to adaptation, whereby patients seek to recover a sense of normality by finding an equilibrium between their lives before and after diagnosis

A qualitative study of patients' experience of living with inflammatory bowel disease: A preliminary focus on the notion of adaptation.

This study investigates the lived experience of inflammatory bowel disease with the aim of examining the process of adapting to life with inflammatory bowel disease. Adaptation is often referred to as the desirable outcome in chronic illnesses such as inflammatory bowel disease; yet little is known as to how this is achieved. A total of 10 Crohn's and 12 ulcerative colitis patients recruited from online support networks participated in individual, semi-structured interviews. The study has identified the notion of a 'new normal' as central to adaptation, whereby patients seek to recover a sense of normality by finding an equilibrium between their lives before and after diagnosis

Using item response theory (IRT) to improve the efficiency of the Simple Clinical Colitis Activity Index (SCCAI) for patients with ulcerative colitis

Background The SCCAI was designed to facilitate assessment of disease activity in ulcerative colitis (UC). We aimed to interrogate the metric properties of individual items of the SCCAI using item response theory (IRT) analysis, to simplify and improve its performance. Methods The original 9-item SCCAI was collected through TrueColours, a real-time software platform which allows remote entry and monitoring of patients with UC. Data were securely uploaded onto Dementias Platform UK Data Portal, where they were analysed in Stata 16.1 SE. A 2-parameter (2-PL) logistic IRT model was estimated to evaluate each item of the SCCAI for its informativeness (discrimination). A revised scale was generated and re-assessed following systematic removal of items. Results SCCAI data for 516 UC patients (41 years, SD = 15) treated in Oxford were examined. After initial item deletion (Erythema nodosum, Pyoderma gangrenosum), a 7-item scale was estimated. Discrimination values (information) ranged from 0.41 to 2.52 indicating selected item inefficiency with three items < 1.70 which is a suggested discriminatory value for optimal efficiency. Systematic item deletions found that a 4-item scale (bowel frequency day; bowel frequency nocturnal; urgency to defaecation; rectal bleeding) was more informative and discriminatory of trait severity (discrimination values of 1.50 to 2.78). The 4-item scale possesses higher scalability and unidimensionality, suggesting that the responses to items are either direct endorsement (patient selection by symptom) or non-endorsement of the trait (disease activity). Conclusion Reduction of the SCCAI from the original 9-item scale to a 4-item scale provides optimum trait information that will minimise response burden. This new 4-item scale needs validation against other measures of disease activity such as faecal calprotectin, endoscopy and histopathology