One of the principal contaminants present in groundwater is arsenic. Arsenic is poisonous and can cause a variety of health issues.
Let us understand the concept of arsenic poisoning in water. We shall also look at the sources of exposure, the harmful effects, and ways to eliminate arsenic from water.
Table of Contents
- Here are some key facts of arsenic poisoning in a nutshell.
- What is arsenic?
- Sources of arsenic
- How does arsenic get into the body?
- What happens to the arsenic that enters the human body?
- Effects of Arsenic
- Complications linked to long-term consumption of arsenic
- How do you diagnose arsenic poisoning?
- Treatment methods
- Prevention and control of arsenic exposure
- Acceptable levels of arsenic in groundwater
- Frequently Asked Questions about Arsenic Poisoning
Here are some key facts of arsenic poisoning in a nutshell.
Arsenic is a naturally occurring metalloid present in groundwater in many countries.
There are two forms of arsenic of which the inorganic form is highly toxic. You find this inorganic form of arsenic in groundwater.
Arsenic in its inorganic form can contaminate water. Using such contaminated water for drinking, preparation of food and irrigation can pose considerable threats to our health.
Arsenic is carcinogenic. Hence, long-term exposure to arsenic through water and food can cause cancer. People exposed to arsenic poisoning have also suffered from cardiovascular diseases and diabetes.
Unborn children have also been affected by arsenic poisoning. It has a detrimental effect on cognitive development and is a cause of premature deaths in young adults.
What is arsenic?
Arsenic, a metalloid, is naturally available in the earth’s crust. You can find traces of arsenic in rocks, air, soil, and most importantly water. It is a metalloid because it has many properties that metals have.
Arsenic is present in two forms, inorganic, and organic. The inorganic arsenic is the more common of the two. Countries like India, China, Bangladesh, the USA, Mexico, Argentina, and Chile contain significant amounts of inorganic arsenic in groundwater. You find organic food in seafood. It is a comparatively milder toxic form of arsenic.
Sources of arsenic
We have already seen that arsenic is present in the earth’s crust in its natural form. However, the greatest threat to humans comes from consuming water and food contaminated with arsenic. Let us look at the different sources of arsenic.
Arsenic is an important alloying agent used in the glass, pigments, textiles, paper, metal adhesives, wood preservatives, and ammunition manufacturing industries. You can also find arsenic in the tanning industry, and to some extent in the pesticides and pharmaceutical industry.
Inorganic arsenic are present in high quantities in groundwater. Crops irrigated with water conta
Plants like tobacco absorb arsenic directly from the soil. Therefore, people habituated to smoking tobacco products are at a higher risk of exposure to arsenic.
How does arsenic get into the body?
Arsenic can enter our human body in a variety of ways. The most common entry is through contaminated food and water. There have been instances of people inhaling arsenic or absorbing it through the skin.
What happens to the arsenic that enters the human body?
The intestine absorbs the arsenic that you consume through drinking water or food. It then passes through the bloodstream to various organs in the body.
The immunity system of the body is capable of eliminating small amounts of arsenic through urine. However, if the contamination is high, the arsenic accumulates inside the body and causes a condition known as Arsenicosis (Arsenic Poisoning).
Effects of Arsenic
Inorganic arsenic is a cancer-causing agent. Exposure to arsenic can cause acute as well as long-term effects. We shall look at the immediate symptoms of arsenic poisoning.
A person swallowing arsenic will show the following symptoms within 30 minutes.
- A persistent headache
- Severe diarrhoea
- Feeling of drowsiness
Inhaling arsenic or consuming it in a less concentrated form is also harmful. The symptoms can take some time to develop. The patient starts experiencing convulsions as the poisoning progresses. You can even notice the decolourisation of the fingernails.
Here are the symptoms generally associated with severe cases of arsenic poisoning.
- A lingering metallic taste in the mouth accompanied by garlicky breath
- Secretion of excessive saliva
- Difficulties in swallowing
- Passage of blood in the urine
- Experience cramping muscles
- Suffer from hair loss
- Stomach cramps and convulsions
- Excessive sweating
- Vomiting coupled with diarrhoea
Heavy poisoning can induce seizures and shock leading to coma and eventually, death.
Extensive consumption of arsenic over a long period can have disastrous effects on the overall health of the individual. We have seen that arsenic is a dangerous carcinogenic agent. The complications associated with long-term consumption of arsenic are as follows.
- Difficulties in digesting food
- Complications in the nervous symptoms such as hearing problems or loss of sensations in the limbs
- Liver disease
How do you diagnose arsenic poisoning?
Pathological testing is the right way to diagnose arsenic poisoning. Urine tests carried out within a day or two of suspected arsenic poisoning can give you an accurate measure of when the poisoning occurred. These are the preliminary tests carried out to determine arsenic poisoning.
In case of acute poisoning, pathological tests of the patients’ hair, blood, and fingernails can confirm the presence of arsenic in the body. However, these tests offer accurate results if the exposure to arsenic is for over a period of 12 months.
The diagnostic tests do not show the effects arsenic can have on the patient’s health.
The treatment depends on the type and the stage of the arsenic poisoning.
There are ways to remove arsenic from the body before it causes damage. Some methods aim to minimize or repair the damage after it occurs.
Here are some of the treatment methods.
- People working in industries where arsenic contamination is common should remove the clothes that could be contaminated with arsenic
- They should wash their clothes thoroughly before using them again
- Similarly, they should clean and rinse the affected areas of the skin
- In case of arsenic contamination in blood, the best treatment is to have blood transfusions
- If your heart shows signs of failing, it is advisable to take heart medications
- Use mineral supplements that can lower the risk of heart rhythm problems
- Observe kidney functions and take immediate remedial action in case of detection of arsenic in the urine.
Another conventional treatment method is Bowel Irrigation. This method involves the passing of a particular medicinal solution through the gastrointestinal tract whereby it helps flush out the contents. This method is beneficial in removing traces of arsenic as it prevents the absorption of arsenic into the gut.
Chelation therapy is also a popular treatment method. Here, you use special chemicals like dimercaptosuccinic acid and dimercaprol that helps in isolating arsenic from the blood proteins.
Prevention and control of arsenic exposure
Acceptable levels of arsenic in groundwater
It will be excellent if there are no traces of arsenic in groundwater. However, it is not practically possible. Therefore, the World Health Organization has stipulated the maximum acceptable levels of arsenic in groundwater as 10µg/litre.
Different countries have specified their national standards depending on the levels of arsenic contamination. For example, Bangladesh, one of the worst affected countries, has specified the national standard of 50µg/litre.
However, the US National Research Council has estimated that 1 in 100 additional cancer-related deaths are because of lifetime exposure to drinking water containing arsenic up to 50µg/litre.