Assessment of cyanide and some heavy metals concentration in consumable cassava flour “lafun” across Osogbo metropolis, Nigeria

Abstract

Introduction: Cassava, a naturally flourishing tuberous plant in Nigeria which has been source to varieties of food in its raw, semi-processed, and processed forms has helped reduced poverty and hunger. Cassava in its various food forms contains varying amount of elements like cyanide, copper, selenium, iron, lead, nickel, cadmium and zinc which are essential elements for man, animal and plants but become toxic if the homeostatic mechanisms maintaining their physiological limit are disrupted or their concentration is very high at certain levels. The significant concentration of heavy metals in cassava flour and prolong consumption can damage the health of man. This research work determined the concentration of cyanide and some metal toxicant in cassava flour from Osogbo metropolis. Methodology: Samples were collected across five markets in Osogbo metropolis and analyzed for cyanide, copper, selenium, iron, lead, nickel, cadmium and zinc. Cyanide concentration was determined using UV/visible spectrophotometer, cadmium and selenium using titrimetric methods, while lead, nickel and cadmium were determined using the atomic absorption spectrophotometer. Results: Across all the samples analyzed, the result showed that the ranges of concentration for cyanide was 0.03-0.09mg/kg, copper 0.35-0.62mg/kg, selenium 3.46-5.43mg/kg, iron 0.1-0.6mg/kg, lead 0.01-0.34mg/kg, nickel 0.20-0.49mg/kg, cadmium 0.01-0.05mg/kg, zinc 0.182-0.31mg/kg. The concentration of cyanide, copper, selenium, iron, nickel, cadmium, and zinc are within the NIS permissible limit. Conclusion: The concentration of lead (0.34mg/kg) was found higher in Akindeko market than the NIS permissible limit of 0.1mg/kg for edible cassava flour. Hence, this study clearly advises that there is need for citizen advocacy, continuous monitoring and supervision to improve the hygienic preparation and storage of cassava flour in order to protect man.

Oil Spills in the Niger Delta Region, Nigeria: Environmental Fate of Toxic Volatile Organics.

“…The eld of environmental toxicology is an element of environmental science and environmental studies, which covers several aspects including; protection of water, soil, sheries and wildlife management, protection of endangered species, habitat and ecosystem conservation etc. (Albers, 2002;Sawyerr et al, 2018;Raimi, 2019;Okoyen et al, 2020).…”

Potential Toxic levels of Cyanide and Heavy Metals in Cassava Flour Sold in Selected Markets in Oke Ogun Community, Oyo State, Nigeria

“…The cassava plant is the highest producer of carbohydrates among crop plants with perhaps the exception of sugarcane. The plant is characterized by palmate lobed leaves, inconspicuous owers and a large, starchy, tuberous root with a tough papery brown bark and white to yellow esh (New World Encyclopedia, 2008;Sawyerr et al, 2018). It is one of the most perishable tuber crops with a high postharvest loss (Diasolua et al, 2003;Sawyerr et al, 2018).…”

“…The plant is characterized by palmate lobed leaves, inconspicuous owers and a large, starchy, tuberous root with a tough papery brown bark and white to yellow esh (New World Encyclopedia, 2008;Sawyerr et al, 2018). It is one of the most perishable tuber crops with a high postharvest loss (Diasolua et al, 2003;Sawyerr et al, 2018). Anatomically cassava root is not a tuberous root, but a true root, which cannot be used for vegetative propagation.…”

“…The parenchyma, which is the edible portion of the fresh root, comprises approximately 85% of the total weight, consisting of the xylem vessels radially distributed in a matrix of starch containing cells (Wheatley and Chuzel, 1993). The cyanide concentration in cassava varies in different parts of the plant, according to variety, location, age, and environmental conditions (Sawyerr et al, 2018). Cassava our, a processed product from cassava, popularly known as "lafu" in Yoruba language is a staple food in Nigeria which contains essential and bene cial minerals needed for the body morphological processes.…”

“…Cassava our, a processed product from cassava, popularly known as "lafu" in Yoruba language is a staple food in Nigeria which contains essential and bene cial minerals needed for the body morphological processes. It is a rich source of carbohydrate, often referred to as the major fuel of the body tissues (Robert, 2000;Sawyerr et al, 2018) that releases energy needed by the body to function properly in its daily activities. Human activities (anthropogenic sources) could favour the presence of toxic contaminants like cyanide and heavy metals in cassava our which may render it un t for human consumption especially when they are in high concentration Suleiman et al, 2019;Morufu, 2021;Morufu et al, 2021;.…”