This study presents a comparative assessment of polycyclic aromatic hydrocarbons (PAHs) in surface and groundwater from industrial and rural zones of Sri Ganganagar District, India. Water samples were collected from representative sites — effluent discharge points, canals and wells in industrial areas and streams, ponds and hand-pumped wells in rural/agricultural zones — during two seasonal campaigns to capture post-monsoon and dry-season variability. Samples were extracted using solid-phase extraction and analyzed by gas chromatography–mass spectrometry (GC–MS) for 16 priority PAHs. Spatial and seasonal patterns were evaluated, and source apportionment was inferred using diagnostic ratios and principal component analysis. Human-health risk potential was screened using estimated daily intakes and carcinogenic potency equivalence factors. Results indicate that PAH concentrations in industrial-area water bodies were consistently elevated relative to rural sites, with heavier-ring (4–6 ring) PAHs more prevalent near industrial discharges and combustion-related hotspots, while low-molecular-weight PAHs were relatively more abundant in some agricultural run-off locations. Seasonal variation showed higher dissolved PAH loads during the dry season, likely due to reduced dilution. Diagnostic ratios and multivariate analysis point to mixed sources: pyrogenic inputs (vehicular and combustion emissions) dominated industrial sites, whereas petrogenic contributions (fuel/oil residues and agrochemical inputs) were more important in selected rural locations. Preliminary risk screening identified potential sites where lifetime cancer risk via drinking-water exposure may exceed commonly used screening thresholds, suggesting the need for targeted mitigation.