Introduction
The arsenic atom, on the Periodic Table, is a chemical element represented by the symbol "As" and has the atomic number 33. Here's a simplified guide:
Element Name: Arsenic
Symbol: As
Atomic Number: 33
Atomic Mass: About 74.92 atomic mass units (amu)
Category: Metalloid (It has properties of both metals and nonmetals.)
State at Room Temperature: Arsenic can exist in various allotropes, including a metallic form and several non-metallic forms. At room temperature, it can be found as a brittle, silver-grey, metallic-looking solid.
Arsenic is known for its toxicity and has both natural and human-made sources. It's commonly found in the Earth's crust and can enter the environment through mining, industrial processes, and agricultural activities. Arsenic exposure can have harmful effects on human health, making it important to track and regulate its presence in drinking water and other sources.
Sources of Arsenic
Organic arsenic (arsenate) is found in a variety of foods.
Inorganic arsenate or arsenite: brown rice, pesticides, beer, table salt, water, paint, cosmetics, pigments, rat poison, glass and mirror manufacture, fungicides, wood preservatives; commercial chicken feed.
Treated timber (very common in New Zealand and Australia).
Geothermal water (Some Central North Island geothermal waters have among the highest levels of arsenic in the world).
Arsenic contamination is widespread in New Zealand due to its dependence on arsenic-treated soft woods and the popularity of bathing in geothermal hot pools. Some waterways, such as the Waikato River, are contaminated with arsenic from geothermal waters.
Health Effects
Arsenic toxicity can have a wide range of adverse effects on human health.
Here's a bulleted summary of some of the potential effects:
Short-term Effects:
Acute poisoning can lead to symptoms like abdominal pain, vomiting, diarrhoea, and muscle cramps.
Skin changes, including pigmentation changes and skin lesions.
Cardiovascular effects, such as increased heart rate and blood pressure.
Long-term Effects:
Increased risk of various cancers, including skin, lung, bladder, and kidney cancer.
Neurological effects, such as peripheral neuropathy, cognitive impairments, and developmental issues in children.
Gastrointestinal problems, including chronic gastritis and increased risk of gastrointestinal cancers.
Respiratory issues, including chronic cough and lung diseases.
Cardiovascular problems, such as atherosclerosis and heart disease.
Diabetes and endocrine system disruption.
Kidney damage and increased risk of kidney diseases.
Reproductive and developmental issues, including low birth weight and developmental delays in children.
Compromised immune system function, making individuals more susceptible to infections.
Nail and hair changes, including horizontal white lines on nails (Mees lines).
It's important to note that the severity of arsenic toxicity and its effects can vary depending on the level and duration of exposure, individual susceptibility, and the source of arsenic contamination (e.g., drinking water, occupational exposure). Managing and mitigating arsenic exposure is crucial to preventing these adverse health effects.
Mineral Antagonists to Arsenic
Mineral antagonists to arsenic are substances that can help counteract the toxic effects of arsenic exposure in the body. These antagonists can bind to arsenic and reduce its harmful impact. Some mineral antagonists to arsenic include:
Selenium: Selenium is a trace element that can antagonise the toxic effects of arsenic. It can help in the detoxification of arsenic by forming less toxic compounds when they interact.
Zinc: Zinc is another mineral that can mitigate arsenic toxicity. It can interfere with the absorption of arsenic in the intestines and help reduce its uptake by the body.
Iron: Iron supplementation may be effective in reducing arsenic absorption in the gastrointestinal tract, as both iron and arsenic may compete for absorption sites.
Calcium: Calcium-rich diets or supplements can reduce the absorption of arsenic, as calcium and arsenic can interact in the intestines.
Magnesium: Magnesium is another mineral that can interact with arsenic and reduce its toxicity.
Cysteine: Cysteine is an amino acid that can bind to arsenic and facilitate its excretion from the body.
It's important to note that while these minerals can act as antagonists to arsenic, they should be used under the guidance of a healthcare professional, especially in cases of arsenic exposure or toxicity. The effectiveness of these antagonists may vary depending on individual circumstances, and their use should be part of a comprehensive treatment plan.
Hair Analysis and Arsenic
Hair tissue mineral analysis (HTMA) is a forensic test that analyses the mineral content in a hair sample. While HTMA primarily focuses on the measurement of various minerals, including essential and toxic elements, it can also provide insights into the body's arsenic levels.
Here's how HTMA can relate to arsenic:
Arsenic Measurement: HTMA can detect the presence and concentration of arsenic in the hair tissue. Arsenic is one of the toxic elements routinely tested in HTMA because of its potential health risks.
Toxicity Assessment: Arsenic is a heavy metal that can be toxic to the human body, even at low levels of exposure. HTMA can help identify elevated arsenic levels in the hair, which may suggest chronic or acute exposure to this toxic element.
Health Implications: High levels of arsenic in the body can have serious health consequences, including skin problems, respiratory issues, cardiovascular problems, and an increased risk of cancer. Interpretation of HTMA results with elevated arsenic levels should prompt further investigation into potential sources of exposure and health effects.
Source Identification: HTMA may not only detect arsenic but also provide clues about potential sources of exposure. For example, if arsenic levels are elevated, it may be important to investigate the individual's environment, occupation, diet, or lifestyle for potential sources of arsenic exposure.
Monitoring and Intervention: For individuals with elevated arsenic levels detected through HTMA, healthcare practitioners can provide guidance on reducing exposure and minimising health risks. This may include lifestyle changes, dietary modifications, or specific interventions aimed at reducing arsenic absorption or promoting its excretion.
Long-Term Monitoring: HTMA can also be used for long-term monitoring of arsenic levels. Regular testing can help assess the effectiveness of interventions and track changes in arsenic exposure over time.
It's important to note that interpreting HTMA results, including arsenic levels, should be done by healthcare practitioners or experts with knowledge of mineral analysis and toxicology. Arsenic exposure can occur through various sources, including contaminated water, certain foods, occupational exposure, and environmental factors. Identifying the source of exposure and taking appropriate measures to reduce it's crucial for minimising the health risks associated with arsenic.