The myth that sharks can smell a drop of blood from a mile away is popular, but it is not entirely accurate. While it is true that sharks have a highly developed sense of smell, their abilities have been greatly exaggerated in popular culture.
Sharks have an incredible sense of smell, which is used to detect prey, mates, and potential environmental threats. The sense of smell is located in their olfactory organs, which are located in their heads, and the organs are incredibly sensitive to odors.
However, the range of a shark's sense of smell depends on several factors, including the concentration of the odor, the current in the water, and the shark species. While some species of sharks have been shown to detect a drop of blood from several hundred meters, a mile is too far for even the most sensitive shark's sense of smell to detect a drop of blood.