Produced water which is the largest waste discharge from the production phase of oil gas wells has several components of toxic concern, ranging from heavy metals to soluble hydrocarbons. Management is normally aimed at minimizing or reducing the toxicity of discharged volumes. This study evaluated the physico-chemical properties and some trace metals constituents of ten produced water samples from five selected oil fields in Niger Delta to determine the extent of compliance with standards of discharge. The pH values ranged from 7.47 to 8.30; temperature ranged from 21.90 to 24.70°C; Alkalinity ranged from 49.00 to 340.00 mgL-1; salinity ranged from 2700.00 to 4400.00 mgL-1; turbidity ranged from 10.00 to 79.00; conductivity ranged from 126.50 to 198.00 μScm-1; TDS ranged from 3200.00 to 7000.00mgL-1; Mg2+ hardness ranged 47.00 to 100.00 mgL-1; Ca2+ ranged from 94.00 to 200.00 mgL-1; total hardness ranged from 141.00 to 300.00 mgL-1 and CO2 ranged from 10.00 to 87.00 mgL-1. The concentrations of some trace metals like Zn, Cd, Cu, Pb, and Mn were within acceptable limits while others such as Fe, Cr and Ni are higher than the regulatory limit for nearshore. Most on the metals and physicochemical properties correlated positively showing strong association.
