Soils from Nigerian Farming Region Contaminated with Heavy Metals
The researchers sampled and analyzed soils from the Ohaji and Umuagwo and Owerri regions of the South Eastern part of Nigeria. They found that levels of lead, cadmium and nickel were enough to be toxic when the fruits, grains and vegetables grown from that region were eaten.
Lead and other heavy metals can be toxic to most of the body’s organs. Particularly susceptible organs include the liver, heart, kidneys, bones and nerves. As these tissues become overwhelmed by heavy metal content, their processes can slow and even shut down, as the cells cannot function properly. This can cause memory loss, delirium, headaches, convulsions, gastrointestinal pain, kidney failure, dementia, hallucination and many other symptoms.
The researchers found that the corn, soybean and rice crops contained the highest levels of lead, cadmium and nickel among grains. Mandarins and pineapples grown in the region contained some of the highest levels of lead, cadmium and nickel among the fruits.
Rice grown in the region was found to contain 3.53 grams per kilogram of lead and .034 grams per kilo of cadmium.
To use a comparison, the International Standards for heavy metals for foods, drawn from the European Union’s Codex Alimentarius, the US FDA, the European Commission and Australia render a maximum allowable heavy metal content for solid foods at 6 parts per million for lead and 0.1 parts per million for cadmium.
The content of lead and cadmium found in the Nigerian rice by the Nigerian researchers was equivalent to 3,530 parts per million, and the cadmium content in the rice was 34 parts per million.
The researchers also found that levels of lead and cadmium in cassava root meal were as high as 19,420 parts per million and 49 parts per million respectively (19.4 grams per kilo and .049 grams per kilo). Cassava root meal, in addition to corn, soy and rice, are meal stables eaten by local Nigerians and many other people around the world.
A Rich Land Gone Toxic
This region, part of the Imo state of Nigeria, has been one of the most natural resource-rich regions in all of Africa. The area is rich in minerals, natural gas and oil. Prior to a few decades ago, it was also lush in forested vegetation that provided rich soils for growing food. Bounded by the River Niger, the rain forests were dense with rubber trees, bamboo, palm and mahogany.
Over the past few decades, a flurry of exploitation of these resources has produced levels of toxicity that are poisoning residents. The combination of mining, gas and oil drilling, clear-cutting, and pesticide-intensive farming practices has turned this rich region into a toxic state.
This is not the first farming region in the world found to have toxic soils. In 2009, soil studies from the Chinese Academy of Sciences found high levels of cadmium and lead in soils from South China. The toxic sources were attributed to nearby mining operations. Food importers from around the world were quick to reduce food purchases from that region.
Coming Home to Roost
While those among first world countries may think that Nigeria or China are far away, the very same industries that have operated in Nigeria and China are also operating across the U.S., South America and throughout the Asian continent – in regions with cropland that produce our foods. Mining operations and air pollutants can pelt the air and waters that feed crops with these toxic heavy metals and others – including cadmium, mercury and arsenic. Pesticides are also a primary source of heavy metals found in soils. Corn and soybean crops have been especially susceptible to greater pesticide use because genetically modified seeds are increasingly being planted for these crops. Genetically modified corn and soybeans have been designed to tolerate greater pesticide spraying.
Food imported from these regions may be concerning, but what is more concerning is that these toxic problems provide a sped-up version of what is coming for the rest of the world’s food supply. And the looming health crisis within populations eating these high levels of heavy metals may not show a clear link to their food consumption until its too late.
Orisakwe OE, Nduka JK, Amadi CN, Dike DO, Bede O. Heavy metals health risk assessment for population via consumption of food crops and fruits in Owerri, South Eastern, Nigeria. Chem Cent J. 2012 Aug 1;6(1):77.
Zhuang P, McBride MB, Xia H, Li N, Li Z. Health risk from heavy metals via consumption of food crops in the vicinity of Dabaoshan mine, South China. Sci Total Environ. 2009 Feb 15;407(5):1551-61.
Choi YY. International/National Standards for Heavy Metals in Food. Gov Lab. 2011 Oct.
Adams C. The Living Cleanse: Detoxification and Cleansing Using Living Foods and Safe Natural Strategies. Logical Books, 2011.
Case Adams is a California Naturopath with a PhD in Natural Health Sciences, and Board Certified Alternative Medicine Practitioner. He has authored 26 books on natural healing strategies. “My journey into writing about alternative medicine began about 9:30 one evening after I finished with a patient at the clinic I practiced at over a decade ago. I had just spent the last two hours explaining how diet, sleep and other lifestyle choices create health problems and how changes in these, along with certain herbal medicines and other natural strategies can radically yet safely turn our health around. As I drove home that night, I realized this knowledge should be available to more people. So I began writing about health with a mission to reach those who desperately need this information. The strategies in my books and articles are backed by scientific evidence along with wisdom handed down through traditional medicines for thousands of years.” Case connects with nature by surfing, hiking, running, biking and according to Dad, being a total beach bum.