ABSTRACT
The presence of phenolic compounds in aquatic systems is due to natural phenomena or effluents from domestic, industrial as well as agricultural activities which may have deleterious impacts on human health and aquatic environments. Phenolic compounds are likely to enter the aquifer mainly through decomposed dead plants and animals and discharge from various industries especially coal-based industries. It is crucial to point out that groundwater is significantly less polluted compared with other water sources, such as rivers, which may be representative of the aquifers’ natural attenuation capacity. Nevertheless, such compounds were often found in aquifers at concentrations higher than in rivers, suggesting that more work was required to understand their activity in aquifers. A wide range of phenolic compounds as well as their metabolites and by-products present in groundwater even at minute levels, under certain conditions may endanger freshwater bodies due to its accumulation in a relatively long period. Among the 1,678 National Priorities List (NPL) by Environmental Protection Agency (EPA), phenol was found in at least 595 lists. They can be exposed to the human body through ingestion, inhalation, and dermal routes and may pose severe health threats such as cardiovascular disease, damage to skin, kidneys, and lungs. This chapter outlined the key sources of emissions, their possible pathways, exposure to humans, and their toxicological assessment. The human health risk oral route of exposure is higher than that of dermal and inhalation routes when exposed to due to the phenolic compounds. Although the risks due to total phenol are not very high, it may result in highly toxic or even carcinogenic by-products when it reacts with other compounds.
