HNSC 1200 Lecture Notes - Lecture 18: Health Canada, Chlorine, Iodine
Document Summary
Environmental contaminants /pollutants include industrial pollutants, toxic metals and contaminants from packaging. Routine monitoring of chemical contaminants is carried out and a ban is imposed if levels are too high. How harmful a contaminant is depends on how long it persists in the environment or in the human body. Some contaminants do not breakdown and are difficult for our body to metabolize or excrete. These contaminants are concerning because they can build up and accumulate at higher and higher concentrations along the food chain. See figure 12. 7: bioaccumulation of toxins in the food chain and table. Heavy metals: lead: displaces minerals, causing function failure of kidneys, liver, nervous system, bone marrow, mercury. Cadmium: causes slow developing, irreversible damage to the liver and kidneys: selenium. Can also be found in lower quantities in fish, eggs, milk rice and drinking water. A naturally occurring element in rocks, lakes, streams and oceans.