A professor of Environmental Chemistry and Environmental Management at Obafemi Awolowo University (OAU), Ile-Ife, Prof. (Mrs.) Aderonke Adetutu Okoya, has advocated the adoption of innovative waste-to-wealth solutions that convert agricultural and industrial solid wastes into low-cost materials for purifying contaminated water.

Okoya made the call while delivering the university’s 415th Inaugural Lecture titled “Managing the Secret Life of Waters for One Health: A Waste to Wealth Approach” held at OAU.

She said the increasing misuse and pollution of water resources had altered water quality in ways not easily detected by ordinary observation.

“Over the years, our use and misuse of water, a vital resource to quality living and survival, has surprisingly altered the important information it carries. Water may appear clean or colourless, but it could have pollutants that are invisible to ordinary eyes,” she said.

Presenting findings from her extensive research on water and wastewater treatment, Okoya highlighted the growing threat posed by industrial discharges containing hazardous pollutants to Nigeria’s water resources and public health.

She noted that rapid industrialisation and poor waste management practices have led to the release of harmful substances such as heavy metals, dyes, pesticides and hydrocarbons into rivers, groundwater and soil.

According to her, many of these pollutants are resistant to natural degradation and tend to accumulate within ecosystems, posing significant health risks including organ damage, cancer and neurological disorders.

Okoya, however, emphasised that practical and affordable solutions exist through the innovative reuse of agricultural and industrial wastes, particularly in the development of adsorbents—materials capable of trapping and removing pollutants from contaminated water.

She explained that agro-wastes commonly available in Nigeria, including maize cobs, cocoa husks, rice husks, sawdust and plastic wastes, can be processed into low-cost adsorbents for removing toxic metals and other contaminants from wastewater.
The professor disclosed that maize cobs processed into biochar and modified with chitosan derived from snail shells demonstrated strong capacity to remove toxic metals such as lead and chromium from polluted water.

According to her, experimental results showed that the modified maize cob adsorbent achieved removal efficiencies of up to 90 per cent for lead, underscoring its potential as an affordable and locally sourced alternative to expensive imported water treatment materials.

“This shows that agricultural wastes such as maize cobs can be converted into valuable materials for environmental remediation rather than constituting nuisance in the environment,” she said.

Okoya urged government agencies, industries and households to adopt research-based innovations to strengthen conventional water treatment systems, noting that such approaches align with Sustainable Development Goals (SDGs) 3, 6 and 12 relating to health, clean water and sanitation, and responsible consumption and production.
She added that the outcomes of the research hold relevance for local, national and international development efforts aimed at improving environmental sustainability and public health.

“Agricultural wastes such as maize cobs can be converted into valuable materials for environmental remediation rather than constituting nuisance in the environment. 

“Government and households can make use of our findings to improve the conventional water supply treatment facilities in line with SDG 3, 6 and 12. The products of these researches have relevance in both local, national and international development.”