Zinc is naturally present in water. The average zinc concentration in seawater is 0.6-5 ppb. Rivers generally contain between 5 and 10 ppb zinc. Algae contain 20-700 ppm, sea fish and shells contain 3-25 ppm, oysters contain 100-900 ppm and lobsters contain 7-50 ppm.
Cyanides (more exactly as cyanogenic glycozides) exist in cassavaroots, and fruit seeds as apricots, prunes, peaches, almonds etc. Cyanide is historically found in the seeds â¦of some fruits. Applesseeds contain cyanide, but a person would have to eat a lot ofapple seeds for the cyanide to have any negative effects. Cyanide is natural found in certain foods. This includes cassava,almonds, pits of some types of fruit, and Lima beans.
1 Photography, chemical research, synthetic plastics, metal processing, and electroplating industries use cyanide. 2  Plants containing cyanide include apricot pits and a type of potato called cassava.3  Fortunately, only chronic or massive ingestion of any of these plants or pits can lead to serious cyanide poisoning.atient Comments Share Your Story. Common sources of cyanide poisoning include: 1  Fires: Smoke inhalation during the burning of common substances such as rubber, plastic, and silk can create cyanide fumes. 2  Photography, chemical research, synthetic plastics, metal processing, and electroplating industries use cyanide.