Metal Contamination in Soils

Contaminated soil is spread through careless dumping.

It's taken years to achieve the successes that have given us a better quality of life, but it's only in the last decade that we've begun to count the cost for our efforts. Our soil is contaminated with metal and it's going to take more than a unified commitment to undo the damage that's been done.

How Our Soil Has Become Contaminated With Metal

Household paints have added to the metal contamination of soil

Although some metals are distributed naturally throughout the earth's soil, none are toxic and none are threatening human and animal life. Industries, however, are contaminating urban and agricultural soils through mining, manufacturing, landfills and waste sites where chemicals have been dumped and buried. Farmers have added to the contamination with insecticides, and residents are destroying the soil through pesticides, paints and other household chemicals.

Dangers Of Metal Contamination To People

Children are suffering from the effects of metal contamination in soil

The four most common metals contaminating soil are lead, cadmium, arsenic and mercury, and the danger comes with long-term contact, such as eating fruits and vegetables that have been grown in the soil. Some of the issues from exposure are slow development and behavioral problems in children, attacks on the central nervous system, skin poisoning, kidney and liver diseases, severe headaches and memory loss.

Spreading Naturally

Metal contamination in the soil is being spread by rain and streams.

The contamination from landfill and waste sites is being spread throughout all the soil every time it rains. It seeps into underground streams, joins up with open streams and spreads it for miles around. It invades drinking wells and farmer's fields and then we eat the cattle and drink the milk from cows that have feasted in these contaminated fields. Surveys are being built near and around these landfill sites on contaminated soil where residents will grow vegetables in their gardens. Pooled waters that have rested in the contamination are evaporated into the air only to be rained down in other areas.

Issues In India

Irrigation systems are using untreated water and spreading the contamination

Soil in places like India is being contaminated through waste water irrigation and poor drainage. The sewers are draining this wastewater back into the ground along with metal contamination. A recent study was conducted and recorded by members of the Banaras Hindu University in India who studied the effects of untreated water in relation to metal contamination. Their study concluded that the use of wastewater for irrigation has increased the metal contamination in the edible portions of vegetables, and that there is a potential health risk threatening because of these contaminates.

Solutions

Unknowingly, every cigarette butt adds to the pollution problem

Lead has been removed from gasoline and from many industrial and residential products. Industries in North America are changing their methods of disposing of waste materials and manufacturers are looking to change the main battery component from cadmium to something less hazardous. But the dangers will continue because too many people aren't recycling things like batteries, but are still tossing them into regular garbage which ends up in landfill sites, further contaminating the soil. Cigarette smoking is a major source of cadmium exposure and not only with the smoke issue but because the butts are being carelessly tossed onto the ground and into the soil.

References

• US Library of Medicine: Heavy Metal Contamination of Soil
• US Dept of Agriculture: Heavy Metal Soil Contamination

Resources

• Imperial College, London, UK: Hazards of Metal Contamination