<p>Polycyclic Aromatic Hydrocarbons (PAHs) can bioaccumulate in seafood, such as shellfish, posing a significant threat to consumers. This study assessed pollution index and cancer risk of PAHs in shellfish species from Lagos Lagoon and its implication on blue economy. Five shellfish species—bigfisted swimming crab (<i>Callinectes amnicola</i>), lobster (<i>Panulirus regius</i>), oyster (<i>Crassostrea gasar</i>), pink shrimp (<i>Penaeus notialis</i>), and tiger shrimp (<i>Penaeus monodon</i>)—were collected from the landing sites of Makoko, Okobaba, and Agboyi creeks within the lagoon. The samples were extracted for PAHs using standard methods, and quantification was performed using Gas Chromatography-Flame Ionization Detector (GC-FID). Data were analyzed using both descriptive and inferential statistical tools. The ∑PAH variations in bigfisted swimming crab, lobster, oyster, pink shrimp, and tiger shrimp ranged from 2.3 to 4.76, 0.69 to 4.44, 6.6 to 14.99, 4.13 to 17.27, and 3.1 to 5.61 (mg/kg wet weight), respectively, across the sampling locations. The ∑PAHs were higher in pink shrimps and oysters compared to other shellfish species. The ∑PAH concentrations in oysters and pink shrimps were significantly (<i>p</i> &lt; 0.05) higher than those in the other three species (bigfisted swimming crab s, lobsters, and tiger shrimps). The bigfisted swimming crab and tiger shrimp exhibited diagnostic ratios &gt; 1.0, suggesting petrogenic sources of PAHs, while the diagnostic ratios &lt; 1.0 in lobster, oyster, and pink shrimp indicated pyrogenic or combustion sources. The study revealed that the estimated total toxicity equivalent concentrations in the shellfish exceeded screening values, indicating potential carcinogenic health risks to consumers of these shellfish species.</p>