Phthalates and Heavy Metals in Sewer and Outlet Stream in a part of Lagos Southwest Nigeria

Abstract

Abstract Contaminants and pollutants impact on the availability of clean water for the human population is huge as clean water is increasingly scarce for human consumption on earth most especially in major cities of the world; As water is used they are heavily contaminated and hence there is the need to examine the persistent pollutants most especially phthalates and heavy metals in wastewater and outlet stream. This research examined the level of dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), and heavy metals viz; Pb, Cr, Cd, As and Hg in the sewer and outlet stream in a part of Lagos, Nigeria. DMP ranged from 0.0070 ± 0.036 to 0.0278 ± 0.324, DEP ranged from 0.0367 ± 0.204 to 0.0526 ± 0.496, and DBP ranged from 0.0406 ± 0.241 to 0.1472 ± 1.667 µg/mL, lead ranged from 0.117 ± 0.024 to 0.157 ± 0.048, chromium ranged from nd (not detected) to 0.319 ± 0.245, cadmium ranged from 0.004 ± 0.002 to 0.063 ± 0.021, arsenic ranged from 0.002 ± 0.001 to 0.021 ± 0.006, and mercury ranged from nd to 0.007 ± 0.001 µg/mL. The concentration of lead in this study was higher than the WHO recommended value of 0.1 mg/L in surface water. This research established that phthalates and heavy metals were released into the wastewater from the immediate environment. We suggest that the sewer treatment of the wastewater be reviewed and improved to eliminate the contaminants in the wastewater.