Assessment of the Proximate Compositions and Heavy Metals’ Profiles of Talinum triangulare L., Corchorus olitorius L. and Solanum macrocarpon L. Harvested from Some Farmlands, Roadsides and Markets in Badagry Division of Lagos State, Nigeria

Abstract

The growing concern over the safety of vegetables consumed in some areas of Lagos due to increased discharge of pollutants that cannot be overlooked was the basis for this research. Thus, this study aimed at assessing the proximate compositions and heavy metals’ profiles of Talinum triangulare, Corchorus olitorius and Solanum macrocarpon harvested from some farmlands, roadsides and markets in Badagry division of Lagos State. Leaves of Talinum triangulare, Corchorus olitorius and Solanum macrocarpon were obtained from farmlands, roadsides and markets in different local government areas in Badagry division of Lagos State. Proximate and heavy metals’ analyses were done using standard analytical procedures. Proximate analyses of the three vegetables showed that the vegetables contained moisture, carbohydrate, lipid, crude fibre, fat, and ash at very appreciable quantities. Also, the results of the heavy metals’ analyses revealed the range of Pb(0.01-0.03 mg/kg), Cd(0.01-0.07mg/kg), Fe(1.83-3.78 mg/kg), Cu(0.05-0.23 mg/kg), Mn(0.01-1.06 mg/kg), Zn(0.08-1.01 mg/kg) for farmlands; Pb(0.01-1.06 mg/kg), Cd(0.01-0.07 mg/kg), Fe(1.00-3.30 mg/kg), Cu(0.01-1.03 mg/kg), Mn(0.01-1.06 mg/kg), Zn(0.86-1.08  mg/kg) for roadsides and P(0.01-0.02mg/kg); Cd(0.01-0.04 mg/kg), Fe(1.78-3.02 mg/kg), Cu(0.01-0.08 mg/kg), Mn(0.02-0.12 mg/kg), Zn (0.01-2.01 mg/kg) for markets among the three vegetables in three the local government areas of Badagry division. However, chromium was not detected in the vegetables for all the locations. These metals were below or within WHO permissible limits except for lead and cadmium which were higher in some vegetables from Ojo roadsides and farmlands; lead in Amuwo-Odofin roadsides and Badagry farmlands respectively. It could be inferred from this study that vegetables across the three locations are rich sources of nutrients irrespective of specific points of collections. However, vegetables from roadsides had the highest overall heavy metal concentrations compared to those from farmland and markets and this could be linked to pollution by vehicular emission among others in the study areas. Thus, regular monitoring of the vegetables should be encouraged to checkmate possible health hazards from consumption of these vegetables.