By Ayo Onikoyi

As the environmental challenges of water pollution and contamination become more pressing, a new study has unveiled concerning data about the state of Warri River, a vital water source in Nigeria. Conducted by Isreal Oluwatimileyin Akinwole, Ayodele Christianah Adeboye, and others, the study aimed to assess the physiochemical and heavy metal content in the Warri River.

The findings offer a sobering look at how industrial activities and seasonal changes impact water quality, with potential implications for public health and aquatic life.

In a research paper obtained by our correspondent, Akinwole explained that the study assessed several water quality indicators, comparing them with the Nigeria Standard for Drinking Water Quality (NSDWQ/NIS 554:2015) and World Health Organization (WHO) guidelines.

According to him, samples were collected across five points in the river, representing various industrial and residential zones.

By assessing these factors across both wet and dry seasons, the researchers aimed to understand how these variations affect water quality.

According to Akinwole, the research was carried out following strict protocols outlined by the American Public Health Association (APHA).

Over the course of two seasons, thirteen physicochemical parameters and seven heavy metals were analyzed to gain a comprehensive view of the river’s condition.

Parameters like pH, electrical conductivity (EC), total dissolved solids (TDS), turbidity (Turb), and total phosphorus (TP) were carefully monitored across the seasons.

The results revealed significant spatial and seasonal variations in several parameters.

For example, the pH, EC, TDS, Turbidity, and other indicators showed notable differences depending on the location within the river.

Sampling points closer to areas of high industrial activity, specifically points 3 (WRPC) to 5 (Batan flow station), exhibited elevated levels of contaminants, suggesting that industrial effluent is a major contributor to the pollution of the Warri River.

One of the most alarming findings was the high level of heavy metals like lead (Pb), iron (Fe), and nickel (Ni), which exceeded the permissible limits set by NSDWQ/NIS and WHO guidelines.

While cadmium (Cd) was not detected, other metals showed worrying concentrations, especially iron and nickel.

According to the study, the mean concentration of metals ranked from high to low in the following order: iron, zinc, nickel, copper, lead, and chromium.

Seasonal differences were also observed, particularly with indicators such as oil and grease (O&G) and chemical oxygen demand (COD).

These seasonal shifts reflect how rainfall and dry conditions influence the distribution and concentration of pollutants in the water. The dry season saw higher levels of COD and total phosphorus, underscoring the impact of reduced water flow on pollutant concentration.

In addition to testing for surface water quality, the researchers conducted a sediment analysis to evaluate potential risks to the riverbed ecosystem.

Heavy metals, anions, and other physicochemical properties, including Total Hydrocarbon Content (THC), were assessed in sediment samples from ten high-activity locations along the river. Contaminants in sediments can be long-lasting, threatening both aquatic ecosystems and public health due to bioaccumulation in the food chain.

Using indices like the contamination factor index (CF), geo-accumulation index (Igeo), and the ecological risk index (ERI), the researchers evaluated contamination levels in the sediments.

Results showed low contamination and ecological risk for most heavy metals. However, cadmium was found in concentrations that posed a potential ecological risk, as levels in 80% of sampled locations exceeded safe thresholds.

The study employed advanced statistical methods such as principal component analysis (PCA) and hierarchical clustering analysis (HCA) to trace the sources of heavy metal contamination.

The findings suggest two main contamination sources: PC1 indicated anthropogenic (human-caused) activities, including iron, zinc, nickel, cadmium, and chromium, while PC2 suggested both natural (geogenic) and industrial origins for manganese and lead.

Akinwole noted that these findings point to a clear need for intervention by governmental and environmental bodies to curb pollution in Warri River. He emphasized the importance of monitoring industrial effluent to prevent further degradation, stressing that current pollution levels could have significant ecological and health implications if left unaddressed.

According to him, the high contamination levels in the Warri River sediments, especially for cadmium, underscore the pressing need for government and industry regulation of waste discharge.

Without intervention, the contaminants could continue to pose a long-term threat to both the environment and communities relying on the river for water and fishing.

In summary, the study presents a critical analysis of the Warri River’s current state, highlighting the urgent need for responsible industrial practices. It calls for stringent monitoring and regulation of industrial waste to preserve the health of aquatic ecosystems and protect public health.

Through this study, Akinwole and his team have brought valuable insights to the table, shedding light on how unchecked industrial pollution impacts vital water sources.