Sourcing aliphatic and polycyclic aromatic hydrocarbons (PAHs) in Jinga Shrimp (Metapenaeus affinis) muscle tissues and surface sediments (Study case: Northwest Persian Gulf)

Abstract

The Persian Gulf, known for its abundant oil and gas reserves, faces significant contamination from hydrocarbon compounds originating from industrial activities. This study focused on investigating the distribution and source of aliphatic (AHs) and polycyclic aromatic hydrocarbons (PAHs) in the surface sediments of the Northwestern Persian Gulf and the muscle tissues of Jinga Shrimp (Metapenaeus affinis), one of the most commercially exploited aquatic species. The methodology involved sampling Jinga Shrimp in November 2018 from four important fishing areas in Behrgan and Khormousi Estuary: Imam Khomeini Port (S1), Mahshahr Port (S2), Sejafi (S3), and Behrgan Wharf (S4). After determining the sex of the shrimps, male samples were selected for analysis, and a total of 28 samples were collected. Additionally, sediment samples were collected from the same locations. The pollutants in the samples were quantified using laboratory procedures. The results revealed that the average concentration of aliphatic compounds in Jinga Shrimp was 4800.32 (µg g − 1 DW), while sediment samples showed an estimated value of 2496.69 (µg g − 1 DW). By analyzing the hydrocarbon components, the average concentration of EPA Priority List (PAH-16) and measured PAHs (PAH-29) in Jinga Shrimp were in the ranges of 1095.8 to 2698.3 (ng g − 1 DW) and in sediments were 653.6 to 1019.5 (ng g − 1 DW), respectively. The higher concentration of AHs and PAHs in Jinga Shrimp compared to sediments indicated the petrogenic source of these compounds. The predominant PAHs in both shrimp and sediment samples were the compounds with low molecular weight (LMW). Moreover, the aliphatic composition profiles in shrimps were similar to those in sediments, portraying a gradient of even-to-odd carbon dominance. The study found a positive and direct correlation between hydrocarbon concentrations in both shrimp and sediment samples and the corresponding aliphatics, PAH-16, and PAH-29 groups, affirming the potential of the Jinga Shrimp as an indicator of hydrocarbon pollution.