Heavy metal pollution from industrial and sewage waste in Egypt's Bahr Al-Baqar drain threatens ecosystems and human health. This study analyzed metal accumulation (Mn, Cr, Ni, Co, Fe, Cu, Zn) in water, soil, and vegetation, assessing associated risks. Mn in drain water ranged 0.12–0.63 mg L􀀀 1, peaking at the endpoint. Hazard quotients (HQ) for Mn and Fe were < 1, indicating low immediate risk. Soil metal concentrations exceeded background levels: Co (1.18×), Cr (2.63×), Ni (1.15×), and Mn (1.03×), with contamination factors (CF >1) confirming moderate pollution. The soil hazard index (HI) for ingestion was 0.944, below risk thresholds. Medicinal plants exhibited high bioaccumulation: Arctostaphylos uva-ursi roots accumulated Cu (BF: 30.44) and Zn (20.59), while Rumex acetosa roots showed extreme Ni uptake (BF: 248.43). Transfer factors revealed Sonchus oleraceus translocated Cu efficiently, Triticum aestivum (wheat) transferred Fe, Ni, and Zn, and Urtica dioica (nettle) mobilized Mn. Consumption of crops/plants irrigated with drain water posed critical risks, with hazard indices (HI) reaching 7.5 (children) and 8.8 (adults), far exceeding safety limits. These results confirm the drain's water is unsafe for irrigation without treatment. Plants like Rumex acetosa and Triticum aestivum act as hazardous bioindicators due to excessive metal uptake, requiring strict monitoring. Immediate actions—including wastewater treatment, pollution control, and soil remediation—are vital to reduce health and environmental threats. The study highlights the need to regulate agricultural and medicinal use of plants from contaminated areas, as their metal accumulation poses direct exposure risks.