Heavy metals in urinary stones in the Democratic Republic of Congo

Abstract Background The Democratic Republic of Congo has been a country of intensive mining activities for centuries, but the data on the presence of heavy metals in stones are lacking. This study aimed to identify different heavy metals in urinary tract stones and to investigate their association with the main components of urinary stones. Methods Thirty-six stones from urolithiasis patients (n = 36) followed in 10 hospitals in the Democratic Republic of Congo between January 2016 and September 2019 were analyzed by Fourier transform infrared spectrophotometry. Further analysis using X-ray fluorescence was conducted at the Laboratory of Solids Physics. Results Eight heavy metals were detected in all the stones analyzed. The average (SD) number of heavy metals detected by stone was 5 (1.2). Iron and strontium were detected in all the stones analyzed. Other heavy metals detected included zinc, copper, bromine, rubidium, lead and nickel. Rubidium had the highest concentration in the stones regardless of the sampling site. There was no statistically significant association between the content of heavy metals at the center level and at the crown level of the stones. Rubidium had more affinity with phosphates and purines (p ˂ 0.001). Iron and strontium exhibited a high affinity with weddellite than with whewellite. Conclusion Iron and Strontium were present in all stones analyzed. The presence of heavy metals in stones analyzed might suggest environmental pollution rather than crystalline induction factors.

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Morpho-constitutional analysis of urinary stones from patients with urolithiasis in the Democratic Republic of Congo

African Journal of Urology ◽

10.1186/s12301-021-00207-0 ◽

2021 ◽

Vol 27 (1) ◽

Author(s):

Pablo Kuntima Diasiama Diangienda ◽

Dieudonné Molamba Moningo ◽

Jean-Robert Rissasy Makulo ◽

Ernest Kiswaya Sumaili ◽

Eric Musalu Mafuta ◽

...

Keyword(s):

Uric Acid ◽

Democratic Republic ◽

Democratic Republic Of Congo ◽

Upper Urinary Tract ◽

Sub Saharan Africa ◽

Urinary Stones ◽

Republic Of Congo ◽

Sub Saharan ◽

Main Components ◽

Constitutional Analysis

Abstract Background Urolithiasis is increasingly diagnosed worldwide. Stone analysis is an important part in the assessment of patients with urolithiasis. However, in sub-Saharan Africa, data on the composition of urinary stones are limited. This study aimed to describe the composition and sites of urinary stones and to investigate relationship between socio-demographic characteristics, clinical profile of patients, and the composition of urinary stones. Methods A retrospective analysis of 132 patients with urolithiasis who visited one of the seven hospitals in the Democratic Republic of Congo during eight years of study period (January 2010 to January 2018) was conducted. Stones were analyzed by infrared spectrophotometry. Results Most of stones analyzed (n = 82, 62.1%) originated from the upper urinary tract with a difference across gender (58.5% males vs. 41.5% females, p = 0.001). Only three stones (two from whewellite and one from anhydrous uric acid) were considered pure (2.3%), excluding the protein frame (less than 5%). Whewellite, proteins, and carbapatite were identified in 97.7%, 96.2%, and 80.3% of the stones analyzed, respectively; and in 91.7%, 89.4%, and 67.7% of the nuclei of the stones analyzed, respectively. Taking into account the proportion of each constituent in the stones analyzed, whewellite (68.9%), anhydrous uric acid (10.6%), and carbapatite (8.3%) were the main constituents in respectively 68, 9%, 10.6%, and 8.3% of the stones analyzed. Conclusion Whewellite, anhydrous uric acid, and carbapatite represented the most frequent main components of stones identified, suggesting that dietary hyperoxaluria could be an important factor in lithogenesis in the Democratic Republic of Congo.

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Concurrent Heavy Metal Exposures and Idiopathic Dilated Cardiomyopathy: A Case-Control Study From the Katanga Mining Area of the Democratic Republic of Congo

10.20944/preprints202104.0434.v1 ◽

2021 ◽

Author(s):

Didier Malamba-Lez ◽

Désiré Tshala-Katumbay ◽

Virginie Bito ◽

Jean-Michel RIGO ◽

Richie Kipenge Kyandabike ◽

...

Keyword(s):

Heavy Metals ◽

Dilated Cardiomyopathy ◽

Democratic Republic ◽

Democratic Republic Of Congo ◽

Mining Area ◽

Idiopathic Dilated Cardiomyopathy ◽

Republic Of Congo ◽

Blood Concentrations ◽

Multiple Exposures ◽

Permissible Levels

Blood and/or urine levels of 27 heavy metals were determined by ICPMS in 41 patients with dilated cardiomyopathy (DCM) and 29 presumably healthy subjects from the Katanga Copperbelt (KC), in the Democratic Republic of Congo (DRC). After adjusting for age, gender, education level, and renal function, DCM probability was almost maximal for blood concentrations above 0.75 and 150 µg/dl for arsenic and copper, respectively. Urinary concentrations above 1 for chromium, 20 for copper, 600 for zinc, 30 for selenium, 2 for cadmium, 0.2 for antimony, 0.5 for thallium and 0.05 for uranium, all in μg/g of creatinine, were also associated with increased DCM probability. Concurrent and multiple exposures to heavy metals, well beyond permissible levels, are associated with increased probability for DCM. Study findings warrant screening for metal toxicity in case of DCM and prompt public health measures to reduce exposures in the KC, DRC.

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Verbeekite, monoclinic PdSe2, a new mineral from the Musonoi Cu-Co-Mn-U mine, near Kolwezi, Shaba Province, Democratic Republic of Congo

Mineralogical Magazine ◽

10.1180/0026461026610020 ◽

2002 ◽

Vol 66 (1) ◽

pp. 173-179 ◽

Cited By ~ 8

Author(s):

A. C. Roberts ◽

W. H. Paar ◽

M. A. Cooper ◽

D. Topa ◽

A. J. Criddle ◽

...

Keyword(s):

Democratic Republic ◽

Democratic Republic Of Congo ◽

New Mineral ◽

Mineral Phase ◽

Republic Of Congo ◽

X Ray ◽

Reflected Light ◽

Primary Mineral ◽

Mohs Hardness ◽

The Ideal

AbstractVerbeekite, ideally PdSe2, monoclinic with space-group choicesC2/m,C2 orCm;a= 6.659(7),b= 4.124(5),c= 4.438(6) Å, ß = 92.76(3)°,V= 121.7(4) Å3;a:b:c= 1.6147:1:1.0761, Z = 2, is a new, very rare, primary mineral, intimately associated with secondary oosterboschite {(Pd,Cu)7Se5}, from the Musonoi Cu-Co-Mn-U mine, near Kolwezi, Shaba Province, Democratic Republic of Congo. Additional associated minerals are Cu- and Pd-bearing trogtalite {(Co,Cu,Pd)Se2}, Se-bearing digenite and Se-bearing covellite. The strongest five lines of the X-ray powder-diffraction pattern {din Å (I) (hkl)} are: 4.423(30)(001), 3.496 (30)(110), 2.718(100)(111), 1.955(50)(310 and 1.896(50)(l̄12). The mineral has also been identified, as a single anhedral 25 µm-sized grain, from Hope's Nose, Torquay, Devon, England where it is associated with native gold, chrisstanleyite Ag2Pd3Se4, oosterboschite(?), unnamed Pd2HgSe3and cerussite. At Musonoi, altered verbeekite grains do not exceed 200 µm in size and are anhedral, black, with a black streak and a metallic lustre. The mineral is opaque, brittle, has an uneven fracture, and lacks discernible cleavage. The VHN5ranges 490–610, mean 550 kp/mm2(2 indentations), roughly approximating a Mohs' hardness of 5Ý.Dcalc.= 7.211 g/cm3for the ideal formula. Electron-microprobe analyses (mean of 4 spot analyses) yielded Pd 39.6, Cu 0.5, Se 58.8, total 98.9 wt.%. The empirical formula is (Pd0.99Cu0.02)σ1.01Se1.99, based on Pd+Cu+Se = 3. In plane-polarized reflected light, the mineral is a nondescript grey and is neither pleochroic nor perceptibly bireflectant. Anisotropy is moderate with rotation tints in varying shades of brown. Reflectance spectra and colour values are tabulated. The name honours Dr Théodore Verbeek (1927–1991) who was the first geoscientist to study the Musonoi palladium mineralization in the Democratic Republic of Congo (1955–1967) and who co-discovered this new mineral phase.

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