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Abstract:In this study, the biodegradation of malathion by a culture of acclimated indigenous activated sludge was investigated under aerobic conditions. Specific substrate consumption rates ( rs) of the culture under different initial malathion concentrations of from 5 mg/L to 140 mg/L were calculated. The results showed the potential for using local activated sludge for malathion biodegradation. However, malathion exhibited inhibition of substrate degradation rate at 140 mg/L. Various substrate inhibition models were compared by fitting them to the experimental data using Statistica 7.0 software. Experimentally it was observed that the kinetic biodegradation of malathion was best described by both the Andrews and Yano and Koga models, which gave high coefficients of determination (0.97 and 0.98, respectively). On the other hand, the degradation ability of the activated sludge was found to be weak when the pesticide was used as the sole source of sulfur or phosphorus.

This article is concerned with the study of biodegradation of an organophosphorus herbicide (glyphosate) using unacclimated activated sludge. Glyphosate at different concentrations (0.1, 0.5, 1, 2 and 5 g/L) was tested for cellular growth. On the other hand, the effect of glyphosate on its own biodegradation was studied by evaluating the fittings of different kinetic models (Andrews, Aiba et al., Han and Levenspiel, Luong, Tessier, Webb, Tseng and Wayman, Yano and Koga). According to the obtained results, the activated sludge was able to use glyphosate as the sole carbon source; however, 2 and 5 g/L glyphosate seemed to inhibit cellular growth. Moreover, glyphosate at initial concentrations of 0.1, 0.5 and 1 g/L was completely degraded within 4, 13 and 18 h of incubation, respectively. Yano and Koga model was the best-fit model (R = 0.999, F = 173,106 and P = 0.000006).

Discharging of untreated municipal solid wastes (MSWs) onto land is very widespread in developing countries. e compounds contained in MSW cause a harmful effect to human and environment. Hence, an assessment of the extent of their local impact is of great interest to figure out the pollution they cause. erefore, this study aimed at evaluating the effects of discharge of solid wastes on soil quality within the landfill of Ain-El-Hammam municipality (Algeria). To achieve this, different soil physicochemical parameters were considered: granulometry, electrical conductivity, pH, organic matter content, and heavy metal concentration. e results indicated the influence of the MSW on the physicochemical characteristics of the soil by enhancing the organic matter content of soil (4.53%) and increasing heavy metal content (Cu, Zn, Cd, Pb, Ni, and Cr), which is a clear indication of the level of pollution they are generating.