Heavy Metal Accumulation and Human Health Risk Assessment in Marine Macroalgae From the Veraval Coast, Arabian Sea, Gujarat, India

ABSTRACT Heavy metal contamination in coastal environments is a growing concern due to the persistence, toxicity, and bioaccumulative nature of these elements. Marine macroalgae are effective biomonitors due to their capacity to absorb and concentrate trace metals from seawater. The present study investigated species‐specific accumulation of seven heavy metals, lead (Pb), manganese (Mn), nickel (Ni), cadmium (Cd), copper (Cu), zinc (Zn), and chromium (Cr) in 17 macroalgal species collected from the Veraval coast along the Arabian Sea, Gujarat, India. Metal concentrations were determined following acid digestion of dried algal tissues, and multivariate statistical analyses were applied to evaluate accumulation patterns and sources. Considerable variation in metal concentrations was observed among species. Zn showed the highest mean concentration (79.55 mg kg −1 ), followed by Cr (21.75 mg kg −1 ), and Pb (12.15 mg kg −1 ). Among the studied species, Sargassum cinereum exhibited the highest Zn concentration (95.5 mg kg −1 ), whereas Codium decorticatum showed the highest Cr level (35.8 mg kg −1 ). Bioaccumulation factor values indicated strong uptake capacity, particularly for Zn, with maximum accumulation in Sargassum cinereum (BAF = 837.72). The metal pollution index (MPI) indicated variation in overall metal burden, with Scinaia carnosa (MPI = 17.81) and Grateloupia filicina (MPI = 17.56) showing the highest accumulation potential. Human health risk assessment indicated that target hazard quotient (THQ) values for Cd and Cr exceeded safe limits in several species, resulting in hazard index values ranging from 3.35 to 7.43, suggesting potential non‐carcinogenic health risks. Multivariate analyses, including Pearson correlation, principal component analysis (PCA), and hierarchical cluster analysis (HCA), revealed distinct species‐specific accumulation patterns and indicated the influence of natural geochemical and anthropogenic inputs. Overall, the findings establish marine macroalgae as bioindicators of coastal metal contamination and provide baseline data for monitoring and food safety along the Veraval coast, Gujarat, India.