Municipal solid waste generated in our cities, with an unprecedented population growth, has resulted in degrading environmental quality, thus a major problem for policy makers. The extent of Pb, Cu, Zn, Cd, Hg and Zn contamination in soils of the studied area, where vegetables were grown, using metal contamination factor (CF) and pollution load index were assessed. The concentrations of heavy metals studied were in the order Cu > Zn > Cd > Hg > Pb > Ni, with the highest value (in mg/kg) for Zn (14.15±0.73), Cu (14.15±1.59), Cd (6.57±1.71) and Hg (6.29±0.97) recorded in site SS1. The geoaccumulation index (Igeo) indicated that sites SS3, SS4 and SS5 were uncontaminated, moderately contaminated (1< Igeo<3) for Zn, landfill was moderately to heavily contaminated (1< Igeo<3) for Cu, Cd and for swamp only Hg. Contamination factor (CF) for soils indicated that site SS1 had a very high degree of contamination (CF > 6) for Cu and Cd while the swamp, old dumpsite and downstream had a low contamination (CF<1). The landfill area is moderately contaminated and considering the age and other anthropogenic factors, this environment may become highly polluted in future. This present work could serve as a landmark for contemporary research in ecotoxicology .

In Cameroon waste disposal by open dumping and landfilling are the most practised options. The siting, operation and after-care of landfills remain a challenging task. In this study we assessed water quality of stream, spring and leachate samples around/from the Mussaka landfill through physicochemical, heavy metal, microbial, phytoplankton, and benthic algae analyses. HCO3-, NH4-, NO3- concentrations are all above permissible limits EPA and WHO standards for freshwater systems. Concentrations of Ca2+ and Mg2+ in stream samples were far below standards but far greater (>480 mg/L) in spring and leachate samples. Nickel, lead and cadmium concentrations were above required standards. Contamination factors of all stream samples (CF<3) imply low to moderate contamination but pollution load index for spring sample (PLI>1) imply the spring is polluted. Generally, the obtained concentrations of most of these parameters were far higher for leachate than water samples. Total coliform counts ranged from 3.5 MPN/100mL to 1.1x103 MPN/100 mL. Five E. coli species were detected in all samples in counts ranging from 3.0x102 to 1.0x103CFU/mL. Thirty phytoplankton species belonging to 5 divisions were identified with Bacillariophyta (19 species) having the highest abundance and Euglenophyta (1 species) with least. Ten genera were identified as pollution indicator species. Results of this study justify the assertion that if upgrading options are not sought for the Mussaka landfill, it will become a major source of pollution of aquatic and soil ecosystems within the landfill area and downstream.