Insights about levels and source appointment of petroleum hydrocarbons in Brazilian semi-arid coastal: baseline status assessment for ocean decade targets

Abstract

The Ocean decade (2021)(2022)(2023)(2024)(2025)(2026)(2027)(2028)(2029)(2030) for sustainable development proclaimed in 2017 by the UN, seeks to promote and conserve the sustainable use of oceans, seas, and marine resources. For this, the distribution of n-alkanes, polycyclic aromatic hydrocarbons (PAHs), and biomarkers, in sediments from the Fortaleza coastal zone (Mucuripe harbor (MH) e Inner shelf (ICS)) were used to assess the impacts of anthropogenic activities in the area. The concentrations of total n-alkanes (Σ16 n-alkanes) in MH and ICS sediments varied from 35.9 to 94.9 and 17.9 to 197.3 µg g − 1 , respectively, while the isoprenoids phytane and pristane in MH and ICS sediments ranged from 0.1 to 1.69 ug g − 1 and from 0.14 and 1.20 µg g − 1 , respectively. Most of the sediment samples presented carbon preference index (CPI) values close to unity, indicating that the area is submitted to petroleum-related sources. The concentrations of Σ16 PHAs in MH and ICS sediments varied from 87.0 to 562.0 and 98 to 288.0 ng g − 1 . This work presents the rst investigation of the petroleum biomarkers hopanes and steranes in the Fortaleza coastal zone, in which ΣBiomarkers varied from 0.10 to 1.79 and 0.02 to 0.24 ug g − 1 in MH and ICS sediments, respectively. The presence at stations of biomarkers also indicates petrogenic input. The diagnosis of the distribution of pollutants in the investigated zones of the Fortaleza coast suggests contamination from urban areas and oil spills and vessel tra c. Highlights ▪ Monitoring of pollutants present in surface sediments of the Fortaleza coastal zone. ▪ High levels of n-alkanes indicate intense local urbanization processes. ▪ Predominance of 4-6 ring PAHs indicates pyrolytic origin of the contamination. ▪ Presence of petroleum biomarkers indicates petrogenic inputs at the site. zone indicate the higher levels of the C30 17α(H),21β(H)-hopane in the Mucuripe Harbor, which is typically sourced from crude oil (Garcia et al. 2019), corroborating the higher petrogenic contamination in this zone. ConclusionsThis study provides data on the pollutants concentrations in the surface sediments from Mucuripe Harbor (MH) and Inner Continental Shelf adjacent (ICS) in Fortaleza coastal zone. The high total concentration of n-alkanes and the isoprenoids pristane and phytane indicate that the area is affected by the intense urbanization processes of Fortaleza, the fth largest city in Brazil. Analysis of 16 USEPA PAHs distribution showed a 4-6 rings PAHs predominance over stations, indicating pyrolytic sources as main PAHs input into the Fortaleza coastal sediments, classi ed as low to moderate contamination. In addition, the presence of the petroleum biomarkers hopanes and steranes, widely used as molecular markers for oil pollution, in addition to some biomarker diagnostic ratios, indicated also petrogenic inputs in the coastal studied zones, mostly at the Mucuripe Harbor, consistent with the ship tra c in the area. This research was signi cant to highlight the multiple sources of contamina...

Occurrence, Distribution, and Sources of Aliphatic and Cyclic Hydrocarbons in Sediments from Two Different Lagoons along the Red Sea Coast of Saudi Arabia

“…The coastal ecosystems along the Red Sea shores are severely contaminated with oil-related products [41,42]. Moreover, oil pollution in the coastal environment of Saudi Arabia's Red Sea might occur by sewage discharge from offshore platforms, ship traffic, tour boats, ferries, private yachts, leisure activities, and littering [43][44][45]. Additionally, petroleum-related products can be introduced into the coastal environment through the deposition of transported atmospheric particulate matter, resuspension of soil by winds, and seasonal runoff of streams and floods [46,47].…”