Rice is a cereal grain that is the most widely consumed staple food for a large part of the world’s human population, especially in Asia. It is the agricultural commodity with the third highest worldwide production after sugar cane and maize.
With the recession in our part of the world, rice has now become one of the cheapest and most readily affordable and available staple food, despite being mostly imported.
Even our own locally grown crops like yam, cassava and beans are a lot more expensive to buy. Gone were the days in Nigeria when rice was a festivity meal, it is now eaten in many homes and by many people on a daily basis.
Apart from its relative affordability, it is quite loved by many, a comfort food par excellence. What is chicken stew without rice?
Unfortunately, our ‘dear rice’ has its hitches and those who love it and want to eat should know how to eat it safely. Arsenic, a toxic and highly dangerous chemical element with symbol As, has stealthily invaded our food supply, especially rice. Arsenic in rice has tested at levels capable of triggering symptoms of arsenic poisoning!
How does arsenic get to food?
It shows up in our food through three main sources.
First, it naturally occurs in the earth’s crust, coming in at the 33rd most abundant substance that makes up the outer layer of the earth. It often occurs in higher concentrations with other precious or industrial metals, like gold and tungsten.
Thus, a certain amount of exposure is unavoidable and normal. Some areas, though, have naturally elevated and thus problematic base arsenic levels, especially areas known for mining.
Second, some industries release arsenic into the environment. While those industries connected to mining and refining appear to be the largest emitters, they are not alone. Depending on their proximity to these industries, arsenic can end up in its water and soils, and then in the food grown there.
Third, some pesticides and other agricultural chemicals contain arsenic, which builds up over time in soils where they are used.
For many decades, farmers cultivated cotton using arsenic containing agricultural chemicals. Unfortunately, some of the best places to grow rice today are the same places farmers once grew cotton using arsenic-laced chemicals. In addition, commercial chicken farms used arsenic for a long time as a poultry feed additive.
More problematic is the fact that, the type of arsenic often, though not exclusively, used in agricultural processes is inorganic (meaning it is not bound to carbon but other elements and chemicals) and is far more dangerous to human health than the kind that naturally occurs in the earth’s crust.
Certain parts of the United States have startlingly high levels of arsenic contamination in the soil and water. California and Texas, two of the primary places rice is grown, rank as some of the worst in their nation. Mississippi and Arkansas, also major rice producing regions, show problematic arsenic levels in their soils too.
However, it is not limited to these regions as arsenic contamination is incredibly widespread and problematic across any modern major agricultural region. This is especially the case with areas that have high concentrations of concentrated animal feeding operations, otherwise known as CAFO poultry production.
Poultry litter (chicken manure mixed with bedding) is a major source of arsenic contamination. For many years, industrial factory farms used arsenic as a growth stimulant for chickens. The arsenic causes the chickens to eat more, which means they grow faster, which means the big industrial farms make more money. The problem is that the chicken’s faeces is laced with lots of arsenic. All that manure is then used to fertilise grain and vegetable fields.
The arsenic also ends up in groundwater, which people drink and use to irrigate their crops in many regions.
This results in foods, especially those that tend to uptake more arsenic than others, becoming dangerously high in this contaminant. Rice is one such food.
Rice loves arsenic
Unfortunately, arsenic easily contaminates rice crops for two reasons. First, rice appears to have an innate penchant for picking up this chemical element from the soil. By some estimates, rice is 10 times more efficient than other plants at arsenic uptake.
Second, farmers almost always grow rice in flooded paddies. This method exposes rice to far more arsenic than other grain crops since arsenic is highly water soluble. It is also found in irrigation and other water sources, such as well water.
In 2013, the FDA finally banned arsenic as an additive to chicken feed but the environmental and human damage from decades of use is already done.
What does arsenic do to us?
According to a review of arsenic poisoning and its effect on human health by the United States Environmental Protection Agency, soluble inorganic arsenic can have immediate toxic effects. This means that ingestion of a one-time heavy load can lead to acute gastrointestinal symptoms such as severe vomiting, disturbances of the blood and circulation, damage to the nervous system, hallucinations, psychosis and eventually death. When not deadly, it may reduce blood cells production, break up red blood cells in the circulation, enlarge the liver (causing chronic hepatitis or hepatic cirrhosis), colour the skin (melanosis, hyperkeratosis, desquamation and eventually carcinoma), produce tingling and loss of sensation in the limbs, and cause brain damage.
Long-term exposure to inorganic arsenic in drinking water in Taiwan has caused Blackfoot disease, in which the blood vessels in the lower limbs are severely damaged, resulting eventually in progressive gangrene. However, arsenic exposure has caused other forms of blood vessel disease in the limbs in several other countries.
It can present with non-specific symptoms, which can be present in many other diseases such as palpitations, fatigue, headache, dizziness, insomnia, weakness, nightmares, numbness in the extremities and anaemia
There is strong evidence supporting arsenic playing a part in elevated blood pressure, heart attacks and another circulatory disease. It may also be implicated in diabetes, infertility, stroke and cancers, especially that of the skin, lungs, bladder, kidneys and long-term neurological effects.
In the lungs, asthmatic bronchitis (a cough, expectoration, breathlessness, and restrictive asthma) are common symptoms in long-term insidious exposure. Symptoms of the clinical phase are associated with different complications as the other organs like lungs, liver, muscles, eyes, vessels are affected. Clinical symptoms are associated with biochemical evidence of organ dysfunction as well as high concentrations of arsenic in different organs involved. Liver enlargement (hepatomegaly), spleen enlargement (splenomegaly) and fluid in the abdomen (ascites) are seen in several cases.