د.حكيمة احمد الطالب2026-10-272026-10-27https://dspace.academy.edu.ly/handle/123456789/2685Pollution with petroleum and its products is considered a major problem worldwide. This is due to its impact on human health and the environment. A significant risk to the environment may be created in the presence of petroleum hydrocarbons. Petroleum hydrocarbons are consider the most common groups of persistent organic contaminants and are known to be toxic to many organisms (Huang et al, 2005). Petroleum hydrocarbons along with heavy metals are the most serious pollutants owing to their toxicity (Reddy et al, 2005). Moreover it has been proved that petroleum hydrocarbons cause significant losses in soil quality due to their toxicity to the biological processes catalyzed by soil microorganisms (Peltola, 2008). Some organisms accumulate high concentrations of hydrocarbon compounds due to lack of the enzyme systems which break down hydrocarbon compounds.For many years microorganisms have been used to remove organic matter and toxic chemicals from domestic and manufacturing waste discharge. Undeniably, microorganisms are frequently the only means to convert synthetic chemicals into inorganic compounds. A new aspect in contaminated sites with petroleum hydrocarbon is the emergence of bioremediation as an industry by determining its convenience in such sites. Bioremediation refers to the productive use of microorganisms to remove or detoxify pollutants, usually as contaminants of soils, water or sediments that affect public health (Gallego et al., 2001).The APPLICATION of BIOLOGICAL and CHEMICAL TREATMENT