Polycyclic aromatic hydrocarbons (PAH) in superficial water from a tropical estuarine system: Distribution, seasonal variations, sources and ecological risk assessment

• Published in: Marine pollution bulletin 2018-02, Vol.127, p.352-358
• Main Authors: Santos, Ewerton, Souza, Michel R.R., Vilela Junior, Antônio R., Soares, Laiane S., Frena, Morgana, Alexandre, Marcelo R.
• Format: Article
• Language: English
• Subjects: Aquatic animals; Aquatic biota; Aquatic environment; Aromatic compounds; Aromatic hydrocarbons; Biota; Brackishwater environment; Brazil; Carcinogens; Distribution; Dry season; Ecological risk assessment; Environmental Monitoring; Environmental risk; Estuaries; Estuarine environments; Hydrocarbons; Molecular chains; Molecular weight; PAH; Polycyclic aromatic hydrocarbons; Polycyclic Aromatic Hydrocarbons - analysis; Profiles; Rain; Rainy season; Risk Assessment; Rivers; Seasonal distribution; Seasonal variation; Seasonal variations; Seasons; Source; Studies; Summer; Tropical climate; Water; Water Pollutants, Chemical - analysis; Wet season; Winter
• ISSN: 0025-326X; 1879-3363
• DOI: 10.1016/j.marpolbul.2017.12.014

This study aimed to evaluate the PAH distribution, sources, seasonal variations and ecological risk assessment in superficial water from the Japaratuba River, Brazil. PAH concentrations ranged from 4 to 119ngL−1. It was observed that the PAH total concentrations and profiles showed significant differences when comparing the dry season (summer) with the rainy season (winter). Furthermore, most of the PAH originated from pyrogenic sources in the winter, whereas a mixture of sources was observed in the summer. PAH concentration levels found in this study were considered lower than those obtained in other estuarine systems. Ecological risk assessment was determined for individual PAH, based on the risk quotient (RQ) to evaluate the risk of aquatic biota's exposure to PAH. Results suggested that the Japaratuba River has achieved a moderate degree of ecological risk for high molecular weight, showing the importance of identifying these carcinogenic and mutagenic compounds in aquatic systems. [Display omitted] •The composition profiles of PAH indicated seasonal variations.•4-ring PAH were the most abundant components in the winter season, while 2-rings were the most abundant in the summer season.•The source PAH were mainly from pyrogenic sources.•A method was proposed to assess the ecological risk of ΣPAH and individual PAH.•4-ring PAH accounted for much more ecological risk than 2-ring, 5-ring and 6-ring PAH, mainly in the winter season.