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Heavy Metals Signature in Stream Sediments at Eséka Gold District, Central Africa: A Pre-mining Environmental Assessment

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Abstract

This paper presents the abundances of heavy metals in the sediments of terraces and riverbeds of the Mambahé catchment area, an area with high potential for gold mineralisation in the Central Region of Cameroon. These sediments have been studied to establish the geochemical baseline conditions prior to any mining activities. The data can be used as an analogy for similar metallogenic provinces in regions with a humid tropical climate. The sediments of the river beds and terraces of the Mambahé basin, which drains the gold deposits that have begun to be exploited in other basins, are influenced by the rapid chemical alteration of the surrounding rocks and present high contents of Al (23,241–254,516 mg/kg), Fe (20,003–125,021 mg/kg) and Cr (15–1390 mg/kg), compared to the geochemical background (upper continental crust), generally used for environmental studies. However, other elements have lower values than these geochemical backgrounds. The range of average concentrations measured for these metals is as follows: Mn (258.24–2324.16 mg/kg), V (30.9–159.3 mg/kg), Ni (3.6–38.71 mg/kg), Zn (13–71.1 mg/kg), Cu (4.1–40.6 mg/kg), Co (2.39–21.69 mg/kg), Pb (2.22–12.09 mg/kg), Cd (0.018–0.153 mg/kg) and Mo (0.2–1.64 mg/kg). Considering the factors governing sediment accumulation such as geology, climate and anthropogenic activities as well as the correlation with commonly used environmental geochemical backgrounds, it is proposed that the data from this study can be considered as a baseline of environmental contamination in this area of planned major mining developments in the region. The results may assist mine planners in setting realistic targets for monitoring and remediation programs.

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References

  1. Al-Mishwat AT (2016) OXDPPM: a software to convert chemical elements between oxides and native elements. J Soft Eng Appl 9(11):561–576

    Google Scholar 

  2. Alloway B, Ayres DC (1997) Chemical principles of environmental pollution. CRC Press, Boca Raton

    Google Scholar 

  3. Ankley GT, Phipps GL, Leonard EN, Benoit DA, Mattson VR, Kosian PA, Mahony JD (1991) Acid-volatile sulfide as a factor mediating cadmium and nickel bioavailability in contaminated sediments. Environ Toxicol Chem Int J 10(10):1299–1307

    CAS  Google Scholar 

  4. Armstrong-Altrin JS (2020) Detrital zircon U–Pb geochronology and geochemistry of the Riachuelos and Palma Sola beach sediments, Veracruz State, Gulf of Mexico: a new insight on palaeoenvironment. J Palaeogeogr 9:1–27

    Google Scholar 

  5. Barceloux DG, Barceloux D (1999) Cobalt J Toxicol Clin Toxicol 37(2):201–216

    CAS  PubMed  Google Scholar 

  6. Batkhishig B, Manzshir B, Munkhtsengel B, Noriyoshi T (2020) PCA analysis of soil geochemical data and environmental assessment of the pre-mining Shuteen area, South Mongolia. Mongolian Geoscientist 51:21–39

  7. Bayiga EC, Bitom D, Ndjigui P-D, Bilong P (2011) Mineralogical and geochemical characterization of weathering products of amphibolites at SW Eska (Northern border of the Nyong unit, SW Cameroon). J Geol Min Res 3(10):281–293

    Google Scholar 

  8. Benito R, Lopez-Ruiz J, Cebria JM, Hertogen J, Doblas M, Oyarzun R, Demaiffe D (1999) Sr and O isotope constraints on source and crustal contamination in the high-K calc-alkaline and shoshonitic Neogene volcanic rocks of SE Spain. Lithos 46(4):773–802

    CAS  Google Scholar 

  9. Blazy P, El-Aïd JDID (2012) Métallurgie du molybdène

  10. Borgmann U, Norwood WP, Reynoldson TB, Rosa F (2001) Identifying cause in sediment assessments: bioavailability and the Sediment Quality Triad. Can J Fish Aquat Sci 58(5):950–960

    CAS  Google Scholar 

  11. Bouchereau JM (1992) Estimation des émissions atmosphériques de métaux lourds en France pour le Cr, le Cu, le Ni, le Pb et le Zn. Centre Interprofessionnel Technique d'Etudes de la Pollution Atmosphérique (CITEPA). Paris

  12. Bucher P, Yetter RA, Dryer FL, Vicenzi EP, Parr TP, Hanson-Parr DM (1999) Condensed-phase species distributions about Al particles reacting in various oxidizers. Comb Flame 117(1–2):351–361

    CAS  Google Scholar 

  13. Caeiro S, Costa MH, Ramos TB, Fernandes F, Silveira N, Coimbra A, Painho M (2005) Assessing heavy metal contamination in Sado Estuary sediment: an index analysis approach. Ecol Ind 5(2):151–169

    CAS  Google Scholar 

  14. Cailteux JLH, Kampunzu AB, Lerouge C, Kaputo AK, Milesi JP (2005) Genesis of sediment-hosted stratiform copper–cobalt deposits, central African Copperbelt. J Afr Earth Sci 42(1–5):134–158

    CAS  Google Scholar 

  15. Callender C (2004) A collision between dynamics and thermodynamics. Entropy 6(1):11–20

    Google Scholar 

  16. Carr MH, Turekian KK (1961) The geochemistry of cobalt. Geochim Cosmochim Acta 23(1–2):9–60

    CAS  Google Scholar 

  17. Cawse PA (1976) A survey of atmospheric trace elements in the UK (No. AERE-R-8398). UKAEA Research Group

  18. Chougong Tchatchouang D, Ngueutchoua G, Dicka Henock E, Ekoa Bessa AZ, Ghepdeu Youbouni GF, BiloungaFUJ, Yongue Fouateu R, Ntyam SC, Arstrong-Altrin JS (2021) Distribution of trace metals and radionuclides contamination in alluvial sediments from the Lobé river in Cameroon. Earth Syst Environ. https://doi.org/10.1007/s41748-021-00251-4

  19. Cortizo AM, Caporossi M, Lettieri G, Etcheverry SB (2000) Vanadate-induced nitric oxide production: role in osteoblast growth and differentiation. Eur J Pharmacol 400(2–3):279–285

    CAS  PubMed  Google Scholar 

  20. Coughtrey PJ, Jackson D, Thorne MC (1983) Radionuclide distribution and transport in terrestrial and aquatic ecosystems. A critical review of data, vol 3. AA Balkema, Rotterdam

    Google Scholar 

  21. Custer CM, Custer TW, Dummer PM, Goldberg D, Franson JC (2016) Concentrations and spatial patterns of organic contaminants in tree swallow (Tachycineta bicolor) eggs at United States and binational Great Lakes Areas of Concern, 2010–2015. Environ Toxicol Chem 35(12):3071–3092

    CAS  PubMed  Google Scholar 

  22. Deng H, Ye ZH, Wong MH (2004) Accumulation of lead, zinc, copper and cadmium by 12 wetland plant species thriving in metal-contaminated sites in China. Environ Pollut 132(1):29–40

    CAS  PubMed  Google Scholar 

  23. Deschamps F, Godard M, Guillot S, Hattori K (2013) Geochemistry of subduction zone serpentinites: a review. Lithos 178:96–127

    CAS  Google Scholar 

  24. Di Toro DM, Mahony JD, Hansen DJ, Scott KJ, Carlson AR, Ankley GT (1992) Acid volatile sulfide predicts the acute toxicity of cadmium and nickel in sediments. Environ Sci Technol 26(1):96–101

    Google Scholar 

  25. Domingo JL (1989) Cobalt in the environment and its toxicological implications. Rev Environ Contam Toxicol 108:105–132

  26. Domingo JL (1996) Vanadium: a review of the reproductive and developmental toxicity. Reprod Toxicol 10(3):175–182

    CAS  PubMed  Google Scholar 

  27. Eba F, Ondo JA, Mba SE, Ollui-M Boulou M, Omva-Zué J (2007) Taux de manganèse accumulé dans quelques plantes vivrières cultivées dans la région manganésifère de Moanda (Gabon). J Soc Ouest Afr Chim 23:69

    Google Scholar 

  28. Ekengele NL, Jung MC, Auguste O, Ngatcha N, Georges E, Lape M (2008) Metals pollution in freshly deposited sediments from river Mingoa, main tributary to the Municipal Lake of Yaounde, Cameroon. Geosci J 12(4):337–347

    Google Scholar 

  29. Ekoa Bessa AZ, El-Amier YA, Doumo EPE, Ngueutchoua N (2018) Assessment of sediments pollution by trace metals in the Moloundou Swamp, Southeast Cameroon. Ann Res Rev Biol 30:1–13

    Google Scholar 

  30. Ekoa Bessa AZ, Ngueutchoua G, Janpou AK, El-Amier YA, Nguetnga OA, Kayou UR, Bisse SB, Mapuna EC, Armstrong-Altrin JS (2020) Heavy metal contamination and its ecological risks in the beach sediments along the Atlantic Ocean (Limbe coastal fringes, Cameroon). Earth Syst Environ 5(2):433–444

    Google Scholar 

  31. Ekoa Bessa AZ, Armstrong-Altrin JS, Fuh GC, Betsi TB, Kelepile T, Ndjigui PD (2021) Mineralogy and geochemistry of the Ngaoundaba Crater Lake sediments, northern Cameroon: implications for provenance and trace metals status. Acta Geochim 40:718–738

  32. Emsley J (ed) (1991) The Elements. Oxford Chemistry Guides. Clarendon Press, Oxford, p 250

    Google Scholar 

  33. Ferrandon M, Chamel A (1986) Etude de quelques aspects du comportement des oligoéléments (Zn, Mn, Fe) fournis par voie foliaire. In Le rôle des oligoéléments en agriculture. Symp Int 2:299–308

    Google Scholar 

  34. Feybesse JL, Johan V, Triboulet C, Guerrot C, Mayaga-Mokolo F, Bouchot V, Eko N’Dong J (1998) The West Central African belt: a model of 25–20 Ga accretion and two-phase orogenic evolution. Precambrian Res 87:161–216

    CAS  Google Scholar 

  35. Filgueiras AV, Lavilla I, Bendicho C (2002) Chemical sequential extraction for metal partitioning in environmental solid samples. J Environ Monit 4(6):823–857

    CAS  PubMed  Google Scholar 

  36. Gilg HA, Frei R (1994) Chronology of magmatism and mineralization in the Kassandra mining area, Greece: the potentials and limitations of dating hydrothermal illites. Geochim Cosmochim Acta 58(9):2107–2122

    CAS  Google Scholar 

  37. Gonçalves CA, Ewert L (1998) Evaluation of the geochemical logging data in hole 959d: Côte d’Ivoire-Ghana transform margin. In: Mascle J, Lohmann GP, and Moullade M (eds) Proceedings of the ocean drilling program, scientific results, vol. 159

  38. Goyer N (1990) Chemical contaminants in office buildings. Am Ind Hyg Assoc J 51(12):615–619

    Google Scholar 

  39. Goyer R, Clarkson T (2001) Toxic effects of metals; ch. 23, Casarett and Doull’s, toxicology—the basic science of poisons

  40. Hakanson L (1980) An ecological risk index for aquatic pollution control A sedimentological approach. Water Res 14:975–1001

    Google Scholar 

  41. Hanif N, Eqani S, Ali SM, Cincinelli A, Ali N, Katsoyiannis IA (2016) Geo-accumulation and enrichment of trace metals in sediments and their associated risks in the Chenab River. Pak J Geochem Explor 165:62–70

    CAS  Google Scholar 

  42. Harikumar PS, Nasir UP, Rahman MM (2009) Distribution of heavy metals in the core sediments of a tropical wetland system. Int J Environ Sci Technol 6(2):225–232

    CAS  Google Scholar 

  43. Hewitt CD, Day JP (1987) Separation of plasma proteins by high performance ionexchange chromatography to determine metal carrier proteins. Trace elements in human health and disease: extended abstracts

  44. Holly MA (1955) Agriculture in Haiti

  45. Hurlbut C, Klein C (1982) Manualo J Mineralogy (afteriamesi? Dana)

  46. Kaback DS, Runnells DD (1980) Geochemistry of molybdenum in some stream sediments and waters. Geochim Cosmochim Acta 44(3):447–456

    CAS  Google Scholar 

  47. Kabata-Pendias A (2011) Trace elements in soils and plants/fourth editions. CRC Taylor and Francis Group, Boca Raton, p 505

    Google Scholar 

  48. Kelepertsis A, Argyraki A, Alexakis D (2006) Multivariate statistics and spatial interpretation of geochemical data for assessing soil contamination by potentially toxic elements in the mining area of Stratoni, north Greece. Geochem Explor Environ Anal 6(4):349–355

    CAS  Google Scholar 

  49. Kelepertzis E, Argyraki A, Daftsis E (2012) Geochemical signature of surface water and stream sediments of a mineralized drainage basin at NE Chalkidiki, Greece: a pre-mining survey. J Geochem Explor 114:70–81

    CAS  Google Scholar 

  50. Khlifi R, Hamza-Chaffai A (2010) Head and neck cancer due to heavy metal exposure via tobacco smoking and professional exposure: a review. Toxicol Appl Pharmacol 248(2):71–88

    CAS  PubMed  Google Scholar 

  51. Kirkwood KL, Zhang L, Thiyagarajan R, Seldeen KL, Troen BR (2018) Myeloid-derived suppressor cells at the intersection of inflammaging and bone fragility. Immunol Investig 47(8):844–854

    CAS  Google Scholar 

  52. Li CS (2000) Modeling trace gas emissions from agricultural ecosystems. Methane emissions from major rice ecosystems in Asia. pp 259–276

  53. Mahan KI, Foderaro TA, Garza TL, Martinez RM, Maroney GA, Trivisonno MR, Willging EM (1987) Microwave digestion techniques in the sequential extraction of calcium, iron, chromium, manganese, lead, and zinc in sediments. Anal Chem 59(7):938–945

    CAS  PubMed  Google Scholar 

  54. Mandeng EPB, Bidjeck LMB, Bessa AZE, Ntomb YD, Wadjou JW, Doumo EPE, Dieudonné LB (2019) Contamination and risk assessment of heavy metals, and uranium of sediments in two watersheds in Abiete-Toko gold district. South Cameroon Heliyon 5:02591

    Google Scholar 

  55. Maurizot P, Abessolo A, Feybesse JL, Johan V, LecomteP (1986) Study and mining exploration in Southwest Cameroon synthesis of the work from 1978 to 1985 Rapp BRGM, p 85 (In French)

  56. Mimba ME, Ohba T, Fils SN, Wirmvem MJ, Tibang EB, Nforba MT, Aka FT (2017) Regional hydrogeochemical mapping for environmental studies in the mineralized Lom Basin, East Cameroon: a pre-industrial mining survey. Hydrology 5(2):15–31

    Google Scholar 

  57. Mimba ME, Ohba T, Fils SN, Nforba MT, Numanami N, Bafon TG, Festus TA, Suh CE (2018) Regional geochemical baseline concentration of potentially toxic trace metals in the mineralized Lom Basin. East Cameroon: a Tool for Contamination Assessment. Geochem Trans 19:1–17

    Google Scholar 

  58. Mookherjee A, Philip R (1979) Distribution of copper, cobalt and nickel in ores and host-rocks, Ingladhal, Karnataka, India. Miner Depos 14(1):33–55

    CAS  Google Scholar 

  59. Moore JW, Ramamoorthy S (1984) Heavy metals in natural waters: appl monitor impact assess. Springer, New York, pp 28–246

    Google Scholar 

  60. Müller G (1969) Index of geoaccumulation in sediments of the Rhine river. Geol J 2:108–118

    Google Scholar 

  61. Ngama EM, Sababa E, Bayiga EC, Bessa AZE, Ndjigui PD, Bilong P (2019) Mineralogical and geochemical characterization of the unconsolidated sands from the Mefou River terrace, Yaoundé area, Southern Cameroon. J Afr Earth Sc 159:103570

    Google Scholar 

  62. Nguemhe FSC, Mimba ME, Nyeck B, Nforba MT, Kankeu B, NjandjockNouck P, Hell JV (2020) GIS-based spatial analysis of regional-scale structural controls on gold mineralization along the betare-oya shear zone, Eastern Cameroon. Nat Resour Res 29:3457–3477

  63. Nan F, Xue H, Chai F, Wang D, Yu F, Shi M, Xiu P (2013) Weakening of the Kuroshio intrusion into the South China sea over the past two decades. J Clim 26(20):8097–8110

    Google Scholar 

  64. Ndema Mbongué JL, Nzenti JP, Cheo ES (2014) Origin and evolution of the formation of the Nyong serie in the Western Border of the Congo Craton. J Geosci Geom 2(2):62–75

    Google Scholar 

  65. Nemati K, Bakar NK, Abas MR, Sobhanzadeh E (2011) Speciation of heavy metals by modified BCR sequential extraction procedure in different depths of sediments from Sungai Buloh, Selangor, Malaysia. J Hazard Mater 192(1):402–410

    CAS  PubMed  Google Scholar 

  66. Ngueyep LM, Kingni ST, Ngounouno MA, Ndi AA (2021) The impact of gold mining exploitation on the physicochemical quality of water: case of Batouri (Cameroon). Int J Energy Water Resour 5(2):159–173

    Google Scholar 

  67. Noa Tang SD, Ekoa Bessa AZ, Brice TK, Ange WKS, Etame J, Bilong P (2021) Heavy metal contamination and ecological risk assessment of overlying water and sediments of Nkozoa Lake (Southern Cameroon). Ann Res Rev Biol 36(4):92–109

  68. Noa Tang SD, Ekoa Bessa AZ, Messina TR, Onana VL, Ndjigui P-D (2021) Risk assessment of trace metals in Mefou River sediments, West-Africa. Heliyon 7:e08606

    Google Scholar 

  69. Nriagu JO, Coker RD (1978) Isotopic composition of sulfur in precipitation within the Great Lakes Basin. Tellus 30(4):365–375

    CAS  Google Scholar 

  70. Rudnick RL, Presper T (1990) Geochemistry of Intermediate/-to High-Pressure Granulites. In: Vielzeuf D, Vidal P (eds) Granulites and Crustal Evolution. NATO ASI Series (Series C: Mathematical and Physical Sciences), vol 311. Springer, Dordrecht. https://doi.org/10.1007/978-94-009-2055-2_27

  71. Nriagu JO (1991) Environmental metal pollution is a global problem. Industry, the environment and human health: in search of a harmonious relationship

  72. Nriagu JO (1996) A history of global metal pollution. Science 272(5259):223–223

    CAS  Google Scholar 

  73. Nsangou MN, Owona S, Owono FM, Ateba CB, Ondoa JM, Ekodeck GE (2020) Evolution of the Edea-Eseka geomorphic units: a “natural laboratory” of a prototype active rifting cross-cutting the Southern Cameroon (West African) passive margin. Geol J 55(6):4864–4888

    Google Scholar 

  74. Olaru DA (1920) Rôle du manganèse en agriculture: son influence sur quelques microbes du sol. JB Baillières et fils

  75. Oumar B, Ekengele NL, Balla OAD (2014) Évaluation du niveau de pollution par les métaux lourds des lacs Bini et Dang, Région de l’Adamaoua, Cameroun. Afr Sci Revue Int Sci Technol 10(2):184–198

    Google Scholar 

  76. Pan J, Plant JA, Voulvoulis N, Oates CJ, Ihlenfeld C (2010) Cadmium levels in Europe: implications for human health. Environ Geochem Health 32(1):1–12

    CAS  PubMed  Google Scholar 

  77. Plumlee GS, Ziegler TL (2003) Treatise on geochemistry. Elsevier, New York

    Google Scholar 

  78. Reimann C, Garrett RG (2005) Geochemical background—concept and reality. Sci Total Environ 350(1–3):12–27

    CAS  PubMed  Google Scholar 

  79. Sababa E, Mbesse CO, Wandji Mouko CN, Ekoa Bessa AZ, Ndjigui P-D (2021) Geochemistry of stream sediments from Eséka area (SW Cameroon): implications for surface process assessment and precious metals (Au, Pd, and Pt) exploration. J Sediment Environ. https://doi.org/10.1007/s43217-021-00082-3

    Article  Google Scholar 

  80. Sabbioni E, Pozzi G, Devos S, Pintar A, Casella L, Fischbach M (1993) The intensity of vanadium (V)-induced cytotoxicity and morphological transformation in BALB/3T3 cells is dependent on glutathione-mediated bioreduction to vanadium (IV). Carcinogenesis 14(12):2565–2568

    CAS  PubMed  Google Scholar 

  81. Salati S, Moore F (2010) Assessment of heavy metal concentration in the Khoshk River water and sediment, Shiraz, Southwest Iran. Environ Monit Assess 164:677–689

    CAS  PubMed  Google Scholar 

  82. Salvarredy Aranguren MM (2008) Contamination en métaux lourds des eaux de surface et des sédiments du Val de Milluni (Andes Boliviennes) par des déchets miniers. Approches géochimique, minéralogique et hydrochimique (Doctoral dissertation, Université de Toulouse, Université Toulouse III-Paul Sabatier)

  83. Scholz F, McManus J, Sommer S (2013) The manganese and iron shuttle in a modern euxinic basin and implications for molybdenum cycling at euxinic ocean margins. Chem Geol 355:56–68

    CAS  Google Scholar 

  84. Simpson SD, Munday PL, Wittenrich ML, Manassa R, Dixson DL, Gagliano M, Yan HY (2011) Ocean acidification erodes crucial auditory behaviour in a marine fish. Biol Lett 7(6):917–920

    CAS  PubMed  PubMed Central  Google Scholar 

  85. Smales AA, Mapper D, Wood AJ (1957) The determination, by radioactivation, of small quantities of nickel, cobalt and copper in rocks, marine sediments and meteorites. Analyst 82(971):75–88

    CAS  Google Scholar 

  86. Sprague WW, Cooper EA, Tošić I, Banks MS (2015) Stereopsis is adaptive for the natural environment. Sci Adv 1(4):e1400254

    PubMed  PubMed Central  Google Scholar 

  87. Stow DAV, Atkin BP (1987) Sediment facies and geochemistry of Upper Jurassic mudrocks in the central North Sea area. In: Conference on petroleum geology of North West Europe, vol 3. pp 797–808

    Google Scholar 

  88. Tehna N, Sababa E, Ekoa Bessa AZ, Etame J (2019) Mine waste and heavy metal pollution in Betare-Oya Mining Area (Eastern Cameroon). Environ Earth Sci Res J 6(4):167–176

    Google Scholar 

  89. Tomlinson DL, Wilson JG, Harris CR, Jeffrey DW (1980) Problems in the assessment of heavy-metal levels in estuaries and the formation of a pollution index. Helgoländermeeresuntersuchungen 33(1–4):566–575

  90. Tsoungui PNE, Ganno S, Njiosseu ELT, Mbongue JLN, Woguia BK, Tamehe LS, Nzenti JP (2020) Geochemical constraints on the origin and tectonic setting of the serpentinized peridotites from the Paleoproterozoic Nyong series, Eseka area, SW Cameroon. Acta Geochim 39(3):404–422

    Google Scholar 

  91. Turekian KK, Wedepohl KH (1961) Distribution of the elements in some major units of the earth’s crust. Geol Soc Am Bull 72(2):175–192

    CAS  Google Scholar 

  92. Türkez H, Yousef MI, Geyikoglu F (2010) Propolis prevents aluminium-induced genetic and hepatic damages in rat liver. Food Chem Toxicol 48(10):2741–2746

    PubMed  Google Scholar 

  93. Usero J, Gamero M, Morillo J, Gracia I (1998) Comparative study of three sequential extraction procedures for metals in marine sediments. Environ Int 24(4):487–496

    CAS  Google Scholar 

  94. Wedepohl KH (1995) The composition of the continental crust. Geochim Cosmochim Acta 59(7):1217–1232

    CAS  Google Scholar 

  95. World Health Organization (2005) Pocket book of hospital care for children: guidelines for the management of common illnesses with limited resources. World Health Organization, Geneva

    Google Scholar 

  96. Yong RN, Phadungchewit Y (1993) pH influence on selectivity and retention of heavy metals in some clay soils. Can Geotech J 30(5):821–833

    CAS  Google Scholar 

  97. Zehra A, Ghalib SA, Khan MZ, Hussain B, Begum A, Khan AR, Lateef TA (2014) Current distribution and status of the wildlife of Deh Akro-2 Wildlife Sanctuary, District Shaheed Benazirabad, Sindh, Pakistan. Int J Biol Biotechnol 11(2–3):351–356

    Google Scholar 

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Authors and Affiliations

  1. Department of Earth Sciences, Faculty of Science, University of Yaoundé I, Yaoundé, Cameroon

    Elisé Sababa & Armel Zacharie Ekoa Bessa

Authors
  1. Elisé Sababa
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Correspondence to Elisé Sababa or Armel Zacharie Ekoa Bessa.

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Appendices

Appendix 1: Conversion factors elements to oxides and oxides to elements with their molar weight

Factor (to element)

Element

 

Oxides

Factor (to oxides)

Molar weight

0.5293

Al

–

Al2O3

1.8895

101.961

0.6994

Fe

–

Fe2O3

1.4297

159.692

0.7745

Mn

–

MnO

1.2912

70.937

Appendix 2: Classes of EF, Igeo, CF, PLI, Er and RI for determination of level of contamination, pollution and risk assessment

EF classes

Enrichment level

I-geo value; classes

Pollution level

EF < 1

No enrichment

I-geo ≤ 0; 0

Unpolluted

EF = 1–3

Minor enrichment

I-geo = 0–1; 1

Unpolluted to moderately polluted

EF = 3–5

Moderate enrichment

I-geo = 1–2; 2

Moderately polluted

EF = 5–10

Moderately severe enrichment

I-geo = 2–3; 3

Moderately to strongly polluted

EF = 25–50

Very severe enrichment

I-geo = 3–4; 4

Strongly polluted

EF > 50

Extremely severe enrichment

I-geo = 4–5; 5

Strongly to very strongly polluted

RI classes

Risk level

CF classes

Contamination level

RI < 150

Low ecological risk

CF < 1

Low contamination

RI = 150–300

Moderate ecological risk

CF = 1–3

Moderate contamination

RI = 300–600

Significant ecological risk

CF = 3–6

Considerable contamination

RI > 600

High ecological risk

CF > 6

High contamination

Er classes

Er level

  

Er < 40

Low potential ecological risk

  

Er = 40–80

Moderate potential ecological risk

  

Er = 80–160

Significant potential ecological risk

  

Er = 160–320

High potential ecological risk

  

Er > 320

Very high potential ecological risk

  

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Sababa, E., Ekoa Bessa, A.Z. Heavy Metals Signature in Stream Sediments at Eséka Gold District, Central Africa: A Pre-mining Environmental Assessment. Chemistry Africa 5, 413–430 (2022). https://doi.org/10.1007/s42250-022-00314-7

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