RESUMO
The present study comparatively investigated the phytotoxic effects of waste engine oil (WEO)-polluted soil exposed to monitored natural attenuation up to 5 and 14 months respectively. Soil was previously polluted with WEO at 0, 1, 2.5, 5 and 10% w/w oil in soil. Although, there was significant reduction in heavy metal concentration of soil as well as total hydrocarbon contents, performance of Sphenostylis stenocarpa was greatly retarded when sown at 5 months after pollution (MAP), with death of all seedlings except in the control. However, growth and yield performances were significantly (p > 0.05) enhanced at 14 MAP. Computation of hazard quotient showed that ecological risk factor initially posed by the presence of heavy metals in the soil at 5 MAP was significantly (p > 0.05) reduced to safe levels at 14 MAP.
Assuntos
Poluição Ambiental/análise , Óleos Industriais/análise , Resíduos Industriais/análise , Poluentes do Solo/análise , Sphenostylis/crescimento & desenvolvimento , Sphenostylis/metabolismo , Monitoramento Ambiental/métodos , Hidrocarbonetos/análise , Hidrocarbonetos/farmacocinética , Metais Pesados/análise , Metais Pesados/farmacocinética , Fatores de Risco , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Solo/química , Poluentes do Solo/farmacocinéticaRESUMO
Susceptibility of the hot pepper (Capsicum annum L.) and the tomato (Lycopersicon esculentum Miller) to spent lubricating oil was investigated in soils supplemented with concentrations of oil ranging from 1-5% w/w. Treatment of soil with 4 and 5% spent oil consistently inhibited germination of both crops. Eighty-four days after sowing, the mean height and leaf area of C. annum in soil treated with 3% spent oil gave the lowest values. These were 3.14 +/- 0.6 cm and 0.24 +/- 0.01 cm(2) compared with respective values of 19.2 +/- 0.2 cm and 2.9 +/- 0.3 cm(2) for control plants. Premature death was observed in the case of L. esculentum plants treated with all tested strengths of spent lubricating oil.