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Original Research Articles Volume : 15, Issue : 10, October, 2026

PRINT ISSN : 2319-7692
Online ISSN : 2319-7706
Issues : 12 per year
Publisher : Excellent Publishers
Email : editorijcmas@gmail.com
submit@ijcmas.com
Editor-in-chief: Dr.M.Prakash
Index Copernicus ICV 2018: 95.39
NAAS RATING 2020: 5.38

Int.J.Curr.Microbiol.App.Sci.2026.15(10) : 349-391
DOI : https://doi.org/10.20546/ijcmas.2026.1510.038


Acidity, Microbial Hazards and Cadmium Exposure in Market Garri from Rivers State, Nigeria: A Probabilistic Chemical and Microbial Risk Assessment

Lasbry Chidi Nnodim1*, Felicia Oluwatoyin Osakuade2, Stella Awaji-Iroyem Aaron3 and Anayo Frank Orji4
1Department of Microbiology, Rivers State University, Port Harcourt, Nigeria
2Federal Institute of Industrial Research Oshodi, Lagos State, Nigeria
3Department of Microbiology, University of Port Harcourt, Port Harcourt, Nigeria
4Emadavistic Medical and Research Laboratory, Nigeria
*Corresponding author
Abstract:

Garri, a fermented and roasted cassava granular, often eaten soaked (flake) or reconstituted (eba) that services as the major source of energy to millions of Southern Nigerians. Analysed were 45 samples from 15 markets in three local government areas (LGAs) of Rivers State, Nigeria, for pH, five microbial groups, proximate composition and four metals. Non-detects were censored except in ranking, and chemical risks were simulated probabilistically. Market mean pH (3.65 to 7.30) differed among LGAs (p = 0.031) and was highest in Ogoni (6.10; about 4.0 elsewhere). Staphylococci occurred in 9 markets (up to 3.40 log CFU/g), fungi in 10 (none in Ogoni) and faecal coliforms only at Etche (pH 3.65; 141 CFU/g). Fungal detection was less likely at higher pH (odds ratio 0.17 per unit, p = 0.002), whereas staphylococcal detection was not (p = 0.25). Cadmium (1.00 to 1.40 mg/kg) drove hazard indices of 5.47 to 7.28 and exceeded regional crop values (0.0008 to 0.01 mg/kg), so it needs confirmation with certified reference materials. The lead margin of exposure for nephrotoxicity was below 1 in Ikwerre and Ogoni. An annual infection risk of about 10−4 would result if one in a million faecal coliforms were enteroinvasive Escherichia coli. Modelled staphylococcal growth was absent at pH 4.0 or below for every assumed minimum pH but substantial in four Ogoni markets. In conclusion, Chokocho in Etche LGA ranked highest for inspection in the main analysis, and acidity did not exclude faecal coliforms.


Keywords: Garri; pH; Staphylococci; faecal coliforms; cadmium; microbial risk assessment; left-censored data


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Lasbry Chidi Nnodim, Felicia Oluwatoyin Osakuade, Stella Awaji-Iroyem Aaron and Anayo Frank Orji. 2026. Acidity, Microbial Hazards and Cadmium Exposure in Market Garri from Rivers State, Nigeria: A Probabilistic Chemical and Microbial Risk Assessment Int.J.Curr.Microbiol.App.Sci. 15(10): 349-391 doi: https://doi.org/10.20546/ijcmas.2026.1510.038
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