Overview
Arsenic ([Ar] 3d¹⁰4s²4p³) is a naturally occurring chemical component within the earth's crust, widely dispersed in the air, water, and soil. Its inorganic form is highly toxic and hazardous to human health.
People usually get exposed to high levels of inorganic arsenic through various sources such as drinking contaminated water, consuming contaminated food, smoking or through its use in food preparation, agricultural irrigation,and industrial procedures, .
Even small quantities of arsenic can quickly dissolve into groundwater, which may subsequently be consumed as a drinking water source. Consumption of arsenic-contaminated drinking water increases cancer risk and other severe health implications.
Prolonged exposure to inorganic arsenic, primarily through water and food consumption, can result in chronic arsenic poisoning. The most distinctive effects include skin lesions and skin cancer. Here is a detailed guide on the impact of arsenic in drinking water and ways to remove it.
Arsenic in Drinking Water
“An estimated 140 million people in at least 70 countries have been drinking water containing arsenic at levels above the WHO provisional guideline value of 10 μg/L (4, 5). This is consistent with recent statistical modelling which suggests between 94 and 220 million people are at risk of exposure to elevated arsenic concentrations in groundwater;” stated the World Health Organization (WHO).
The gravest peril to public health stemming from arsenic is the contamination of groundwater and well water. Inorganic arsenic naturally occurs at higher concentrations in the groundwater and well water of various nations, such as Argentina, Bangladesh, Chile, China, Cambodia, Mexico, Pakistan, the United States of America, India, Vietnam, and more. In the World Health Organization (WHO) study, it has been found that close to 70 countries are forced to drink high levels of arsenic-contaminated water.
Source: Statista
The primary sources of exposure are drinking water, agriculture crops irrigated with arsenic-contaminated water, and food prepared using contaminated water. Additionally, arsenic can be ingested through dietary intake from fish, shellfish, meat, poultry, dairy products, and cereals; however, the levels of exposure through these foods are generally lower compared to groundwater and well water exposure. Seafood contains primarily arsenic in its less harmful organic form, further contributing to dietary arsenic exposure. The world is in dire need of a solution for arsenic removal from well water and groundwater.
Arsenic can form various chemical species depending on its oxidation state and the molecules it bonds with. Here are some common species:
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Arsenic (III) oxide (AS3): Arsenic (III) oxide, also known as arsenous oxide or arsenic trioxide (As2O3), is a white, odorless crystalline solid. It is commonly found in nature as the minerals arsenolite and claudetite.
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Arsenic (V) oxide (AS5): Arsenic (V) oxide, also known as arsenic pentoxide (As2O5), is a white, odorless solid. It is less common than arsenic (III) oxide but still exists in nature. It can be prepared by oxidizing arsenic (III) oxide with concentrated nitric acid.
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Organic Arsenic: Organic arsenic compounds are those where arsenic is covalently bonded to carbon atoms. These compounds can vary widely in their chemical structures and properties. Some common organic arsenic compounds include arsenobetaine, arsenocholine, and arsenosugars. They are often found in marine organisms like fish and shellfish.
It's important to note that arsenic compounds can be highly toxic, particularly inorganic forms. Organic arsenic compounds, while generally less toxic, can still pose health risks if consumed in large amounts.
Health Risks Associated with Arsenic
Arsenic, a systemic poison, poses severe health risks upon prolonged ingestion, potentially causing many diseases and early mortality. Exposure to arsenic can manifest in various ways, including skin lesions, skin, lung, and bladder cancers, as well as gastrointestinal, cardiovascular, and pulmonary ailments. Furthermore, chronic arsenic poisoning hampers the cognitive development of children and teenagers, which has a devastating impact on both short- and long-term health concerns.
Short Term Health Concerns
Arsenic exposure or drinking arsenic-contaminated water has short-term acute health issues such as abdominal pain, diarrhea, vomiting, et cetera which occur immediately and only last for a short span. In some cases, one may experience numbness and tingling of the extremities, muscle cramping, and even death too.
Long Term Health Concerns
“Long-term exposure to arsenic from drinking water and food can cause cancer and skin lesions. It has also been associated with cardiovascular disease and diabetes. In utero and early childhood exposure has been linked to negative impacts on cognitive development and increased deaths in young adults.” according to the World Health Organization (WHO).
Arsenic in the groundwater and well water has potential human health concerns and hazards. Prolonged exposure and consumption of arsenic-contaminated well water and groundwater reflect various health issues such as skin, lung, kidney, and bladder cancer, coronary heart disease, bronchiectasis, hyperkeratosis, and arsenicosis, which is life-threatening. The illness that occurs due to chronic arsenic exposure is known as "arsenicosis."
Long-term exposure to high levels of inorganic arsenic after a minimum exposure of approximately five years has the very first symptoms due to drinking water or food, skin lesions, and pigmentation changes. Some may find it as hard patches on the palms and the soles of the feet, known as hyperkeratosis. It could be a precursor to skin cancer also.
“The International Agency for Research on Cancer has classified arsenic as a class I human carcinogen;” as published by National Center for Biotechnology Information.
Skin cancer due to long-term exposure to arsenic can cause bladder and lung cancer, too. The International Agency for Research on Cancer (IARC) identified arsenic and arsenic compounds as carcinogenic for humans. IARC also mentioned that arsenic in drinking water is carcinogenic to humans and is one of the reasons for cancer.
Source: UNICEF
Inorganic arsenic is more toxic, and its long-term ingestion can be harmful as it affects child development, pulmonary disease, diabetes, and cardiovascular disease. Arsenic-induced myocardial infarction can be a significant cause of excess mortality in some cases. It is also responsible for adverse pregnancy outcomes and infant mortality in young adults in some cases. It can be responsible for multiple cancers, heart attacks, bronchiectasis, hyperkeratosis, arsenicosis, lung disease, and sometimes kidney failure.
Arsenic Treatment Methods
A few possible ways to counter chronic arsenic toxicity are having access to safe, contaminant-free drinking water, a nutritious diet, and routine physical exercise. Effective watershed treatment and adopting cost-efficient conjunctive water usage, coupled with fostering mass awareness, form viable approaches to address the increasing arsenic crisis.
Finding a safe source of drinking water is difficult in these areas where water sources are already limited. An arsenic removal system is needed in the areas where unsafe levels of arsenic have been found or recorded in the drinking water. There are various technologies developed for the removal of arsenic contamination drinking water, as given here.
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Chemical Oxidation
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Biological Oxidation
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Electrocoagulation
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Bucket Treatment Unit (BTU) for home use
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Coagulation, precipitation and filtration
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Adsorption (sorptive filtration)
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Ion exchange
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Membrane filtration (nano-filter)
All the above methods have their usages that can be considered based on the severity of the problem and affordability by the end consumers.
Water Filters for Arsenic Removal
Water filtration through Reverse osmosis (RO) for arsenic removal from well water and groundwater is one current technology used effectivly to treat arsenic-associated toxicities worldwide.
Please note that RO systems provide effective filtration for Arsenic 5 (AS5), not Arsenic 3 (AS3).
Chlorination converts AS3 into AS5. If your water supply contains AS3, and its not chlorinated, typically one must chlorinate in conjunction with Reverse Osmosis filtration.
Depending on the distribution of the arsenic species in the water sourcel, water chlorination might be required to bring the overall Arsenic load below the 10 ppb recommended level. For example if there are 12ppb of arsenic, and if 5ppb are AS5 and 7ppb are AS3, then the RO system should bring down the AS5 level sufficient to bring the overall level below the 10ppb EPA safe level. Please use an arsenic speciation test to be sure of the exact amounts, and if the water is not chlorinated.
Source: Sciencedirect
Reverse osmosis (RO) is a filtration and purification technique that uses the pressure on contaminated water solvents to forcibly pass through a porous membrane in the reverse direction, unlike natural osmosis. Many leading water filtration companies like ‘Perfect Water Technologies, Inc. ’ offerthe Home Master® Reverse Osmosis Systems as effective means of arsenic V (As5) removal for home and officeuses. Home Master® Reverse Osmosis Systems includefilters that remove arsenic from municipal or chlorinated well, ground, or source water. These RO water filters help 99% of 1000s of contaminants and microorganisms to make it drinkable water.
Selecting the Right Water Filter
When selecting a water filter, specific points to be included as the type of contaminants present, filter efficiency, maintenance requirements, cost, and certifications to ensure the filter effectively purifies the water and meets specific needs.
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Water quality
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Contamination
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Storage Capacity
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Budget
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Maintenance cost
One can use the “Reverse Osmosis System Buying Guide” by Home Master® Reverse Osmosis Systems and install the right water filter.
Conclusion
The world needs effective arsenic treatment and arsenic-removing water filters for safer and healthier drinking water. There is a vital nexus between science, public health, and technology. Empowering communities worldwide with this arsenic removal system and its knowledge equips them to fight the invisible threat lurking in well water and groundwater sources. With effective arsenic water filter solutions and testing, the world can pave the way toward a safer, arsenic-free future for all. With each drop of purified water, the world grows into a healthier, arsenic-free world, where every sip is a step towards progress and prosperity.