Source: Earth’s Future
The Nile Delta is densely populated, hosts extensive agriculture, and serves as a critical wetland habitat for multiple species including migrating birds. Water management in the region includes extensive water reuse and discharge of agricultural, domestic, and industrial wastewaters, which can drive accumulation of potentially toxic heavy metals in Nile Delta sediments.
Abotalib et al.  collected sediments from twenty locations along the two branches of the Nile River in the Delta region and analyzed the samples for eight heavy metals (including lead, cadmium, chromium, zinc, nickel, and copper). Their analysis found high levels of multiple metals, with concentrations increasing northward toward the mouth of the Nile. Comparisons with previous measurements indicated that heavy metal concentrations were also increasing over time.
The authors argue that continuing increases in heavy metal concentrations in Nile Delta sediments could threaten human health, the agricultural economy, and ecological function in the Nile Delta. They also suggest that water and soil quality considerations should be included in regional and international water use plans.
Citation: Abotalib, A. Z., Abdelhady, A. A., Heggy, E., Salem, S. G., Ismail, E., Ali, A., & Khalil, M. M. (2023). Irreversible and large-scale heavy metal pollution arising from increased damming and untreated water reuse in the Nile Delta. Earth’s Future, 11, e2022EF002987. https://doi.org/10.1029/2022EF002987
— Benjamin Sulman, Associate Editor, Earth’s Future