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Wastewater irrigation alleviates freshwater scarcity. However, conventional (near)surface irrigation techniques directly expose crops to contaminants. Irrigating wastewater into shallow phreatic zones to raise the water table enhances groundwater evapotranspiration, while using the vadose zone as a bioreactor that attenuates contaminants through dilution, adsorption, and biodegradation. Nevertheless, contaminants may spread across the groundwater, soil, and vegetation. In this study, we focus on the crop contamination risks, and derive a simple analytical model to estimate crop solute uptake. Although crops are not directly exposed to the irrigated wastewater, contaminants (and nutrients) may spread to the root zone. Results show that crop contamination is primarily determined by the root zone water balance, and by solute dispersion and biogeochemical reaction parameters. The model contributes towards identifying hydrogeologically and climatically suitable locations for phreatic zone wastewater irrigation, determining acceptable levels of irrigation water quality, and evaluating crop contamination hazards against the fertigative value of wastewater. • Phreatic zone irrigation raises water table and enhances capillary fluxes to crops. • Vadose zone stored moisture: key water source and contaminant buffer for crops. • Soil in-situ bioremediation and adsorption prevents contaminants from reaching roots. • Analytical model of contaminant transport, attenuation, and crop contamination risks. • Crop risks strongly depend on precipitation shortage and vadose zone stored moisture. [ABSTRACT FROM AUTHOR]