Heavy metals and the food chain;long term effects on the human population.

Heavy Metal Pollution

Introduction

All living things are part of the food chain . no exceptions . Although we experience this principle of dependency daily , it usually gets ignored unless something disrupts the chain and results to detrimental consequences such as food poisoning that may lead to human fatalities or illnesses . Heavy metals are a part of nature and some are even beneficial to the human body but as with most things , too much concentration can have its adverse effects

What Are Heavy Metals

Heavy metals are found in rocks and soils

but these may also accumulate in water forms

when these solid objects get broken down in time . The term heavy metal means any metallic chemical element that has a relatively high density and is toxic or poisonous at low concentrations (ILPI , 2007 , par . 1 Some of the heavy metals that are being considered as threatening are arsenic , cadmium , chromium , copper , lead and mercury

These heavy metals which can also be called minerals have been present in the environment in safe amounts until industrialization has initiated mining activities and technological advances that altered their presence in the food chain . Some of the products that elevated these heavy metals to possible intolerable levels are leaded gasoline and silver-mercury tooth amalgam (Haas , n .d , par . 5 ) Unfortunately , heavy metals cannot be destroyed except through radiation . It is therefore necessary to control its content and the way it is distributed in man 's environment especially when the food chain is concerned

How Do Heavy Metals Seep Into The Food Chain

There are many natural ways by which heavy metals enter the food chain Nature can release heavy metals from boulders and other rock formations by weathering and eventual breakage or erosion . Volcanic eruptions can also release these heavy metals into the air which will eventually accumulate around the surrounding habitat of many living organisms Acidic rains can also break down soils and release heavy metals into streams , lakes , rivers and ground water (Lenntech , 2006 , par . 4

Man also has had a hand in the spillage of heavy metals in his environment . Lead paint and water pipes have been a source of many health problems and intoxications . Copper , for example , can contaminate drinking water because of the copper-based pipes it passes and also from purifying agents that are intended to control the presence of microorganisms . Sewage sludge disposal unto farms is also a means that was originally a good way of garbage disposal but it can also be a path for certain nutrients to seep through the soil in larger quantities that may not be so beneficial after all . In Ohio , for example , sludges are considered rich in nitrogen and phosphorus which are significant sources of nutrients to farms in the vicinity of the sewage treatment plants (The Ohio State University , n .d , par . 1 ) However , it has been found that it also contains unnecessary amounts of cadmium , copper , nickel zinc and lead that can deter the healthy growth of botanical organisms and contaminate the...