Abstract

Anthropogenic activities have contributed to contamination of rivers and creeks within Port Harcourt metropolis, increasing environmental and public health risks. This study assessed the public health risks associated with surface water in communities surrounding Port Harcourt. Surface water samples were collected from five waterfront communities located at Choba, Iwofe, Creek Road, Eagle Island, and Marine Base. Standard analytical methods were employed to determine the physicochemical and microbiological characteristics, and data were analyzed using ANOVA at p<0.05. Physicochemical results showed pH (6.8–7.8) and temperature (28.2–30.8°C) were generally within acceptable limits, while dissolved oxygen ranged from 3.8–5.6 mg/L. Elevated pollution indicators were recorded for Biological oxygen demand (3.8–9.5 mg/L), chemical oxygen demand (28–130 mg/L), Total suspended solid (28–120 mg/L), Electric conductivity (650–22,000 µS/cm), total dissolved solid (320–11,000 mg/L), salinity (0.3–70 ppt) and turbidity (18–110 NTU), with Marine Base and Creek Road showing highest contamination. Heavy metal concentrations were elevated, ranging as follows: Iron (0.45–2.40 mg/L), lead (0.015–0.120 mg/L), Cadmium (0.004–0.030 mg/L), Chromium (0.032–0.190 mg/L), Ni (0.058–0.310 mg/L), Cu (0.38–2.60 mg/L) and Zn (0.92–6.20 mg/L), while Iron (≤ 0.3) Lead (≤ 0.01) Cadmium (≤ 0.003) Chromium (≤ 0.05) Nickel (≤ 0.07) were above WHO/SON limits. Although individual Target Hazard Quotients were below 1, the cumulative Hazard Index (2.228) indicated potential health risk. Microbial loads in water were high: total heterotrophic bacterial counts (1.38×10⁸–1.64×10⁸ CFU/ml), total coliform counts (1.15×10⁶–1.23×10⁶ CFU/ml), fecal coliform counts (1.2×10⁴–2.0×10⁴ CFU/ml), and bacteria counts exceeded WHO standards of 1 x 10²  CFU/ml for THB and 0 CFU/ml for total and fecal coliforms. Predominant bacterial isolated included; Escherichia coli, Pseudomonas, Proteus, Shigella and Salmonella. The study concludes that surface waters from the studied communities are significantly impacted by physicochemical, microbial and heavy metal pollution, posing serious ecological and public health risks. The study highlights the urgent need for effective pollution control.