Seasonal Monitoring of Heavy Metals Contamination of Selected Fruits and Vegetables from Kaura Namoda, Central Market, Zamfara, Nigeria
DOI:
https://doi.org/10.70112/ajsat-2025.14.2.4300Keywords:
Heavy Metals, Fruit, Vegetables, Atomic Absorption Spectrophotometer, Kaura NamodaAbstract
Fruits and vegetables are a primary source of human exposure to heavy metals, as most are consumed raw without undergoing any processing. This research aims to determine the seasonal concentrations of heavy metals-lead (Pb), chromium (Cr), cadmium (Cd), nickel (Ni), copper (Cu), and cobalt (Co)-in onions, spinach, lettuce, and cucumbers obtained from Kaura Namoda, Zamfara State. Samples were collected every four months (quarterly) from the same vendor. Acid digestion techniques and atomic absorption spectroscopy (A.A.S.) were used for sample preparation and analysis. The results show a significant difference in the seasonal concentrations of heavy metals in the selected fruits and vegetables, as determined using ANOVA (P < 0.05). Spinach, lettuce, and cucumber had Pb concentrations of 0.08 mg/kg in Q1; lettuce had 0.017 mg/kg in Q3; and cucumber had Pb concentrations of 0.18 mg/kg in Q4, 0.17 mg/kg in Q3, and 0.13 mg/kg in Q4. Spinach, lettuce, and cucumber appear to be more vulnerable in both dry and wet seasons. In conclusion, there should be continued monitoring and awareness campaigns regarding the potential sources of these heavy metals, such as illegal mining activities, improper use of agrochemicals, and inadequate waste disposal, to support effective management and policy development.
References
[1] M. I. O. Raji et al., “Assessment and seasonal variations of heavy metals and mineral elements in River Sokoto, north-western Nigeria,” Nigerian J. Basic Appl. Sci., vol. 24, no. 2, pp. 9–14, 2016, doi: 10.4314/njbas.v24i2.2.
[2] E. T. Aisien, “Seasonal investigation of heavy metal concentrations in vegetables from Oluku dumpsite and a farmland in Edo State, Nigeria,” Afr. J. Health, Safety Environ., vol. 3, no. 1, pp. 19–25, 2022, doi: 10.52417/ajhse.v3i1.196.
[3] E. A. Oluyemi et al., “Seasonal variations in heavy metal concentrations in soil and some selected crops at a landfill in Nigeria,” Afr. J. Environ. Sci. Technol., vol. 2, no. 5, pp. 89–96, 2008.
[4] Y. Ugya and T. S. Imam, “Temporal heavy metals variation in vegetables sampled at Kasuwan Mata, Kaduna metropolis, Nigeria,” Malaysian J. Sci., vol. 36, no. 2, pp. 63–74, 2017.
[5] AbdulHameed et al., “Assessment of heavy metal content in vegetables and their potential human health risk in Bauchi, Nigeria,” Biol. Environ. Sci. J. Trop., vol. 21, no. 2, 2024, doi: 10.4314/bestj.v21i2.10.
[6] Ahmad et al., “Determination of some heavy metal concentrations in selected fruits and vegetables,” Int. J. Biosci. Agrol. Res. (IJBAR), vol. 5, no. 1, 2024.
[7] J. T. Rasheed et al., “Assessment of heavy metal contents in raw cow milk samples from selected local government areas in Kano State, Nigeria,” Asia J. Sci. Appl. Technol., vol. 12, no. 2, pp. 1–5, 2023, doi: 10.5198/ajsat-2023.12.2.3971.
[8] K. I. Adegbite et al., “Assessment of heavy metal contamination across five selected roadside marketed fruits in Erin-Osun, Osun State,” Fountain J. Basic Med. Health Sci., vol. 1, no. 2, pp. 1–13, 2024.
[9] K. S. Balkhair and M. Ashraf, “Field accumulation risks of heavy metals in soil and vegetable crops irrigated with sewage water in the western region of Saudi Arabia,” Saudi J. Biol. Sci., vol. 23, no. 1, pp. 32–44, 2016.
[10] L. Babafemi et al., “Assessment of heavy metal contamination in fish, fruits, and vegetables in Southwest Nigeria: A systematic review,” 2025, doi: 10.12688/f1000research.157781.2.
[11] M. G. Bala et al., “Assessment of concentration and potential health risks of heavy metals in vegetable samples cultivated in Toro mining site, Bauchi State, Nigeria,” UJMR, Conf. Special Issue, vol. 9, no. 3, 2024, doi: 10.47430/ujmr.2493.057.
[12] F. Jabeen et al., “Heavy metal contamination in vegetables and soil irrigated with sewage water and associated health risks assessment,” J. Environ. Agric. Sci., vol. 22, no. 1, pp. 23–31, 2020.
[13] S. Hembrom et al., “A comprehensive evaluation of heavy metal contamination in foodstuff and associated human health risk: A global perspective,” in Contemporary Environmental Issues and Challenges in the Era of Climate Change. Singapore: Springer, 2020, pp. 33–63.
[14] M. A. Majeed et al., “Occurrence, distribution, and health effects of heavy metals in commercially available vegetables in Karachi,” Int. J. Biol. Biotechnol., vol. 17, pp. 319–328, 2020.
[15] E. Oguh and E. N. Obiwulu, “Human risk from heavy metal pollution and bioaccumulation factor in soil and some edible vegetables around an active auto-mechanic workshop in Chinchaga, Minna, Niger State, Nigeria,” Ann. Ecol. Environ. Sci., vol. 4, no. 1, pp. 12–20, 2020.
[16] N. T. Otukam et al., “Trace metal contents of vegetables in Ogbedigbo Afor, Delta State, Nigeria,” Sci. World J., vol. 20, no. 1, 2025, doi: 10.4314/swj.v20i1.50.
[17] O. Oluwole and C. A. Omolola, “Level of heavy metals in sliced watermelon fruits in selected markets in Akure, Nigeria,” Bull. Natl. Res. Centre, vol. 44, Art. no. 102, 2020, doi: 10.1186/s42269-020-00356-2.
[18] S. Pierrick et al., “Assessment of heavy metal accumulation in vegetables irrigated with water from different sources in Lead City University farms, Ibadan, Nigeria,” J. Capital Dev. Behav. Sci., vol. 12, no. 1, 2024.
[19] K. Yakubu and M. M. Ibrahim, “Evaluation of heavy metals in some selected fruits marketed in Maiduguri, Borno State, Nigeria,” Int. Acad. J. Adv. Pure Appl. Sci. Res., vol. 9, no. 10, 2024.
[20] H. Zhou et al., “Accumulation of heavy metals in vegetable species planted in contaminated soils and the health risk assessment,” Int. J. Environ. Res. Public Health, vol. 13, no. 3, pp. 289–297, 2016.
[21] A. I. Zainab and E. Makwe, “Evaluating the concentration of heavy metals in effluent irrigated vegetables around the industrial area of Abuja, Nigeria,” J. Niger. Acad. Sci., vol. 18, no. 1, 2025, doi: 10.57046/LWQW1466.
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