Assessment of Radiological Hazards and Trace Elements Contents in Seaweeds and their Effects on DNA Damage at the Gulf of Aqaba – Jordan

Abstract

This work investigates the radiological content of gamma emitters and trace elements in two different seaweeds samples grown in the Gulf of Aqaba, Jordan. The measurements were done using gamma spectroscopy, atomic absorption spectrometer (AAS), and comet assay for DNA damage detection. The average values of the detected activity concentrations in (±SD) for ⁴⁰K, ²²⁶Ra, ²²⁸Ra, ²³⁸U, and ²¹⁰Pb were 294.9±56.2 Bq/kg, 47.9±28.2 Bq/kg, 20.3±4.2 Bq/kg, 45.8±5.1 Bq/kg, and 93.4±17.3 Bq/kg, respectively. Most of the maximum concentrations were found at the sites SG1, SG3, and SG5. Analysis of heavy metal levels (Fe, Mn, Zn, Cu, Cr, Co, Cd, Ni, and Pb) in seaweed samples revealed that Cu, Cr, Co, Cd, Ni, and Pb concentrations were below the detection limit of the AAS spectrometer. Additionally, Zn and Mn levels in all samples, as well as Fe levels at sites SG1, SG2, and SG5 were within permissible limits. However, Fe levels exceeded permissible limits at the sites SG1, SG3, and SG4, indicating contamination. Results of the DNA damage assessment showed that samples collected from SG4 and SG5 resulted in the longest tail length (highest DNA damage) than samples collected from other sites which indicates that these sites are more contaminated than other sites. 

In conclusion, the findings indicate that contamination from radionuclides and heavy metals at affected sites is associated with measurable alternations in DNA integrity, suggesting potential genetic damage in exposed seaweeds. These results highlight the need for responsible authorities to implement continuous monitoring and risk assessment of contaminated environments. Immediate remediation actions and stricter regulatory controls are recommended to reduce further DNA damage and protect marine systems.