Aquatic Pollution in Lake Alau: Investigating the Role of Heavy Metals in Water Quality Degradation

1Fabian Zira Lawrence, 2Abasiryu Apagu and 3Luka Lawrence

1Department of Zoology Modibbo Adama University Yola, Adamawa State, Nigeria
2Department of Biological Sciences, Federal University Dutsin-Ma, Kastina State, Nigeria
3Department of Chemistry, Adamawa State College of Education, Hong

*Corresponding author’s Email: ziralawrencefabian@gmail.com, doi.org/10.55639/607.02010012


ABSTRACT

This study assesses the concentrations of heavy metals, including zinc (Zn), copper (Cu), manganese (Mn), cadmium (Cd), lead (Pb), and their impacts on the aquatic ecosystem of Lake Alau. The metal concentrations in the lake’s surface water were found to follow the order: Zn > Cu > Cd > Mn > Pb. Zinc, an essential element for growth and development in living organisms, was detected in higher concentrations (0.58±0.15mg/L) due to anthropogenic activities, including agricultural runoff, industrial discharges, and urban waste. However, its levels did not exceed the permissible limits set by the World Health Organization (WHO) and the United States Environmental Protection Agency (USEPA). The study highlights that while zinc is vital for aquatic organisms, excessive concentrations can be toxic, posing risks to both fish and aquatic biodiversity. Other metals, including copper (0.33±0.08mg/L) and cadmium (0.35±0.17mg/L), also exceeded safety thresholds, presenting significant risks to water quality and aquatic life. Elevated levels of manganese and lead (0.09±0.02mg/L) were similarly linked to industrial pollution, vehicular emissions, and military activities around the lake. Water samples were collected over an eighteen-month period (January 2019 to June 2020) at a depth of 10 cm below the surface using cleaned 1-liter plastic bottles. Heavy metal concentrations were analyzed using an Atomic Absorption
Spectrophotometer (FAAS) after digesting samples with concentrated nitric acid. The findings emphasize the need for improved monitoring and management to mitigate the environmental and health risks posed by heavy metal contamination in Lake Alau. Specifically, targeted environmental monitoring and regulation, impactful policy development, risk mitigation for aquatic life, public health initiatives, and support for future research are essential actions for safeguarding the lake’s ecosystem and the health of surrounding communities.

Keywords:

Heavy Metals,
Water Quality,
Lake Alau
Degradation
Contamination