Unregulated discharge of wastewater in the Mahanadi River Basin: Risk evaluation due to occurrence of polycyclic aromatic hydrocarbon in surface water and sediments

• Published in: Marine pollution bulletin 2022-06, Vol.179, p.113686-113686, Article 113686
• Main Authors: Kurwadkar, Sudarshan, Sethi, Shrikanta Shankar, Mishra, Phoolendra, Ambade, Balram
• Format: Article
• Language: English
• Subjects: Anthracene; Aromatic compounds; Aromatic hydrocarbons; Combustion; Ecological risk; Ecological risk assessment; Environmental risk; Equivalence; Fluvial sediments; Health risks; ILCR; Mahanadi River; PAHs; Phenanthrene; Polycyclic aromatic hydrocarbons; Quotients; Risk assessment; River basins; River water; Rivers; Sediment; Sediment samplers; Sediment samples; Sediments; Surface water; Wastewater; Wastewater discharges; Water analysis; Water pollution; Water sampling
• ISSN: 0025-326X; 1879-3363
• DOI: 10.1016/j.marpolbul.2022.113686

Exposure to polycyclic aromatic hydrocarbons (PAHs) through contaminated water may adversely affect human health and ecology. Water and sediment samples collected from the Mahanadi River Basin (MRB) were analyzed for the presence of sixteen priority PAHs. Results showed that the concentrations of Σ16 PAHs in water and sediments ranged from 13.1 to 685.4 μg/L and 302.6 to 728.2 ng/g. In river water samples, the highest mean concentrations were recorded for Acenaphthylene (18.73 ± 11.61 μg/L) and Benzo(a)Anthracene (10.11 ± 8 μg/L). On the contrary, the maximum concentration was recorded for Phenanthrene (96.18 ± 50.66 ng/g) and Pyrene (76.69 ± 22.73 ng/g) in sediment samples. Human health risk assessment suggests low risk, with incremental lifetime cancer risk (ILCR) being 37.44 × 10−5 for children and 21.82 × 10−5 for adults. In contrast, ecological risk assessment showed a high toxic equivalent quotient of 40.68 ng/g and mutagenic equivalent quotient of 39.74 ng/g suggesting elevated adverse risk to aquatic species. •Surface water and sediment samples in the MRB showed PAHs deposition.•PAHs deposition in the MRB is due to petrogenic, combustion of coal, grass, & wood.•Heavy vehicular traffic & industrial emission leads to higher PAH in surface water.•Higher toxic equivalent quotient of PAHs in sediment samples indicates adverse risk.•Continued release of PAHs and its deposition in the MRB is a serious concern.