The annual reports testing the quality of Israel's coastal waters, published in recent years by the Israel Institute for the Research of Seas and Lakes, show similar findings: "Significant quantities of anthropogenic material are introduced into Israel's Mediterranean coastal waters, both from localized sources (sewage outlets and the coastal rivers) and from decentralized sources (run-off water and atmospheric conduction). As a result, there is significant pollution by heavy metals, nutrients and various organic materials at a number of focal points along the coast."
According to the rules of the Barcelona Charter, ratified by the State of Israel and manifested in laws prohibiting discharge into the sea, it is forbidden to discharge or dispose of waste into the sea, other than under temporary permits given by the exceptional permits committee established by law. Nonetheless, along the Israeli coast there are a not insignificant number of places where industrial and/or domestic sewage waste is allowed to be discharged.
Marine mammals are super-predators at the top of the food chain, and as such they accumulate these pollutants in their bodies through the food they eat: at each stage of the food chain pollutants are collected, becoming more concentrated in the process of biological empowerment (by which the rate at which they accumulate is greater than the rate at which they are excreted). The pollutants collect in the different organs of the marine mammal's body, weakening it and eventually leading to disease and even death.
Also see the next two articles:
- Risso’s dolphin (Grampus griseus) stranding on the coast of Israel (eastern Mediterranean).Autopsy results and trace metal concentrations Risso’s dolphin (Grampus griseus) stranding on the coast of Israel(eastern Mediterranean).Autopsy results and trace metalconcentrations - Efrat Shoham-Frider, Shlomi Amiel, Mia Roditi-Elasar, Nurit Kress.
- Heavy metal levels in bottlenose and striped dolphins oﬀ the Mediterranean coast of Israel - Mia Roditi-Elasar, Dan Kerem, Hava Hornung, Nurit Kress, Efrat Shoham-Frider, Oz Goﬀman, Ehud Spanier