Assessment of polycyclic aromatic hydrocarbons in three environmental components from a tropical estuary in Northeast Brazil

The evaluation of occurrence, risk quotient (RQ), bioaccumulation factor (BAF), and sources of PAH was conducted in Sergipe-Poxim estuarine system. PAH distribution that ranged from 7.1 to 30.9 ng L-1 (surface water, SW), 5.4 to 19.5 ng g(-1) (sediment, S), and 4.3 to 18.1 ng g(-1) (oyster, O), characterized the environment with low contamination; 2-3 (SW), 5-6 (S), and 4 (O) PAH rings accounted for 54.5%, 68.7%, and 87.7%, respectively, along with naphthalene (SW), dibenzo(a,h)anthracene (S), and pyrene (O) as the prevailing compounds. PCA suggested the predominance of particular groups related to SW (LMW-PAH), S (HMW-PAH), and O (pyrene and fluoranthene). Furthermore, one sample of O presented a high PAH bioavailability as shown through the BAF, with emphasis on pyrene (BAF = 26.8). The RQ showed a low to moderate range in SW and S; hence, in-depth information about the possible toxic effect in organisms of this region is required.

Automated summary

The evaluation of PAH in the Sergipe-Poxim estuarine system showed low contamination levels, with naphthalene, dibenzo(a,h)anthracene, and pyrene as the prevailing compounds. Different media in the estuarine system showed varying levels of PAH content and risk quotient, with some bioaccumulation observed in the ecosystem.