Microbial treatment of refinery wastewater enables fluted pumpkin growth and food safety

Authors

• Eziafakaego M. Ibo, Pan African University Life and Earth Sciences Institute (Including Health and Agriculture)
• Odera R. Umeh, Montclair State UniversityFollow
• Oju R. Ibor, University of Calabar
• Chukwunonso P. Okoli, Federal University Ndufu Alike Ikwo
• Azubuike V. Chukwuka, National Environmental Standards and Regulations Enforcement Agency
• Emmanuel D. Omogbemi, University of Ibadan
• Michael U. Orji, Nnamdi Azikiwe University
• Aina O. Adeogun, University of Ibadan

Document Type

Article

Publication Date

12-2026

Journal / Book Title

The Microbe

Abstract

Global water scarcity necessitates the reuse of agricultural wastewater, but safety concerns persist about contaminant transfer to plants. This study examined how treated and untreated petroleum refinery wastewater affected the growth and development of fluted pumpkins over a six-week cultivation period. The novelty lies in our comprehensive assessment of both growth performance and contaminant bioaccumulation in fluted pumpkins. The experimental design planted fluted pumpkin seeds in soils irrigated with 100% treated wastewater, untreated wastewater, or tap water (control). Weekly growth indicators (leaf count and height) and post-harvest parameters (root length, chlorophyll concentration, fresh and dry weight) were measured, and heavy metal and polycyclic aromatic hydrocarbon accumulation in plant tissues was quantified to assess contamination risks. Findings revealed that treated wastewater and the control group promoted robust plant development, with average plant heights of 31.00 cm and 31.33 cm, respectively, compared with 41.00 cm in the control group, whereas untreated effluents severely suppressed growth performance (10.67 cm). The control group achieved 14.00 cm leaves by week 6, while treated groups reached 13.00 cm and 14.00 cm leaves, but untreated wastewater resulted in only 5.00 cm leaves. Plants receiving untreated wastewater irrigation demonstrated alarming concentrations of lead (0.13 ppm), mercury (0.25 ppm), and cadmium (0.12 ppm), alongside PAHs such as pyrene (76.40 ppm) and benzo(a)anthracene (55.43 ppm) in their foliage, creating significant human health concerns upon consumption. Properly treated petroleum refinery wastewater effectively supported fluted pumpkin cultivation compared with untreated wastewater, emphasizing adequate wastewater treatment before agricultural application to safeguard plant quality and public health and to prevent environmental degradation.

DOI

10.1016/j.microb.2026.100793

Rights

This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)

MSU Digital Commons Citation

Ibo, Eziafakaego M.; Umeh, Odera R.; Ibor, Oju R.; Okoli, Chukwunonso P.; Chukwuka, Azubuike V.; Omogbemi, Emmanuel D.; Orji, Michael U.; and Adeogun, Aina O., "Microbial treatment of refinery wastewater enables fluted pumpkin growth and food safety" (2026). Montclair State University Scholarship & Creative Works. 14.
https://digitalcommons.montclair.edu/allpubs/14

Published Citation

Ibo, Eziafakaego M., et al. “Microbial Treatment of Refinery Wastewater Enables Fluted Pumpkin Growth and Food Safety.” The Microbe, vol. 13, Dec. 2026, p. 100793. https://doi.org/10.1016/j.microb.2026.100793.