Genotoxicity Effects of Heavy Metal Pollution on Mangifera indica L. (Mango) Exposed to Roadside Traffic in Makurdi, Nigeria

Jose V. Addy; Ella A. Boniface; Buukume T. Benjamin; Licia M. Addy

doi:10.31557/apjec.1852.20250910

Authors

Jose V. Addy Department of Environmental Sustainability, Federal University of Agriculture, Makurdi, North Central, Nigeria.
Ella A. Boniface Department of Environmental Sustainability, Federal University of Agriculture, Makurdi, North Central, Nigeria. https://orcid.org/0009-0009-0809-1609
Buukume T. Benjamin Department of Environmental Sustainability, Federal University of Agriculture, Makurdi, North Central, Nigeria.
Licia M. Addy Department of Microbiology, Benue State University, Makurdi, Nigeria.

DOI:

https://doi.org/10.31557/apjec.1852.20250910

Keywords:

Genotoxicity, heavy metal, pollutionroadside traffic, DNA fragmentation index, Mangifera indica

Abstract

Objective: The study aimed to assess the genotoxicity effects of heavy metals pollution on Mangifera indica L. (Mango) exposed to roadside traffic from NNPC Petroleum Depot, Makurdi-Nigeria.

Methods: Thirty (30) samples of Mangifera indica (Mango) parts comprising of fruits, bark and roots were washed with distilled water, dried at 40 °C and digested with trioxonitrate (v) acid HNO₃ at 120 °C. Six heavy metals nickel, lead, zinc, copper, cadmium, and chromium were analyzed using Shimadzu AAS 6300 Atomic Absorption Spectrophotometer (AAS).

Results: The mean concentration of Nickel, Zinc, Lead, Copper, Cadmium and chromium in fruits, barks, and roots of Mangifera indica L (Mango) were above the permissible limit of 0.03, 3.00, 0.1, 0.08, 0.03 and 0.05 mg/kg (WHO, 2022) for Nickel, Zinc, Lead (Pb2+), Copper, Cadmium and Chromium respectively except the mean concentration of Zinc in fruit, bark, and root that was within the permissible limit of 3mg/kg (WHO, 2022). The DNA amounts in fruits and roots at the NNPC Petrol Depot were 555 and 422 respectively, while from the control site were 208 and 180, respectively. The DNA content (ng/μl) in fruits and roots at the NNPC Depot were 940 and 840, respectively, while the DNA amounts in fruits and roots from the control site were 202 and
210, respectively. The DNA content in fruits and roots after the NNPC Depot, Apir-Makurdi were 748 and 540, respectively, while the DNA amounts in fruits and roots from the control site were 211 and 201 respectively.

Discussion: One-way ANOVA showed that the concentration of heavy metals in parts of Mangifera indica L (Mango) is statistically significant at (P<0.05). Genotoxic effects of heavy metals pollution from roadside traffic on mango plants cause oxidative stress, which plays a major role in DNA-damage induction with more DNA content, fragmentation as well as more smearing of DNA. The DNA fragmentation index from all the polluted sites was above forty percent (40 %), indicating the level of severity. From these findings, people that consume these Mango fruits are prone to metal pollution capable of causing cancer.

Conclusion: Policies on reducing air pollution should be enforced while creating awareness that food crops cultivated near roadside should not be consumed.