Distribution, composition and risk assessment of hydrocarbon residue in surficial sediments of El-Dakhla, El-Kharga and El-Farafra oases, Egypt

Abstract

This work examined the polycyclic aromatic hydrocarbons (PAHs) and n-alkanes quantities, sources, and hazards in sediments collected from the Egyptian Western Desert Oases namely: Dakhla, Kharga and Farafra oases. The n-alkane (C9–C20) residue concentrations have ranged from 0.66 to 2417.91 µg/g recorded for the three Oases. On the other hand, the total n-alkane ranged from 448.54 µg/g to 8442.60 µg/g. Higher carbon preference index (CPI) values (> 1.0) proposed that the natural sources could be the main contributor to n-alkanes in the Oases sediment. GC-MS/MS (selected reaction monitoring (SRM) method) was used for the determination of the ΣPAHs concentrations in the studied sediments. The ΣPAHs concentrations (ng/g, dry weight) in the studied three Oases varied from 10.18 to 790.14, 10.55 to 667.72, and from 38.27 to 362.77 for the Kharga, Dakhla and Farafra Oases, respectively. The higher molecular weight PAHs were the most abundant compounds in the collected samples. Assessing potential ecological and human health issues highlighted serious dangers for living things and people. All the investigated PAHs had cancer risk values between 1.43 × 10–4 and 1.64 × 10–1, this finding suggests that PAHs in the samples under study pose a moderate risk of cancer. The main sources of PAHs in this study are biomass, natural gas, and gasoline/diesel burning emissions.

Polycyclic aromatic hydrocarbons content of food, water and vegetables and associated cancer risk assessment in Southern Nigeria

“…The relative error range of the method precision ranged from 0.1 to 5.0%, which ensures accuracy across the analytical procedures. N-alkanes and PAH residue’s recovery rates of water and sediment samples ranged from 92.4% to 107.8% [ 30 ].…”

Trace metals concentration and risk assessment in the southeastern Mediterranean sediments

“…When non-essential metals like Pb and Cd bioaccumulate in tissues, they can cause intoxication, cellular and tissue damage, diminished fertility, malfunction of several organs, and even cell death. These metals are often strong poisons even at very low concentrations [11][12][13][14]. The European Union has included lead and cadmium in its hazardous metal standards, and the US Food and Drug Administration has designated nickel and chromium as dangerous metals [15,16].…”