PAH determination in effluent and sludge samples of paper industry

Polycyclic aromatic hydrocarbons (PAHs) are persistent organic pollutant, present ubiquitously in the environment. Due to their carcinogenic and mutagenic nature, these can cause severe harm to living beings. PAHs are produced by incomplete combustion of wood, coal, fuel oils etc. Besides aluminium processing plants and refineries, paper industry is also a source of PAHs. PAHs are produced during processing of paper due to combustion of coal, wood, use of chemicals, excessive heat and pressure. The determination of PAHs in paper industry effluents and sludge was carried out. Samples were extracted with different solvents, based on quantitative recoveries of PAHs. Samples were analysed for six PAHs, namely, naphthalene, fluorene, phenanthrene, anthracene, fluoranthene and pyrene. PAHs were quantified using an HPLC procedure involving acetonitrile:water (60:40) as mobile phase in an isocratic mode. Both effluent and sludge samples were collected in two different seasons. Total concentration of above mentioned PAHs in effluents ranged between 39.25 to 51.03 μg L−1 and in sludge between 2.11 to 2.33 mg kg−1. Source diagnosis of PAHs, as petrogenic or pyrogenic, on the basis of isomer pair ratios is also discussed.