Arsenic is a naturally occurring element found in water, air, and soil. Inorganic arsenic, the predominant form in water, is highly toxic. This element is odorless, tasteless, and colorless, making it impossible to detect without specific testing. Proactive testing is essential to ensure the safety of drinking water.
Why Test Your Water for Arsenic
Testing your water for arsenic is important due to significant health implications from long-term exposure. Chronic ingestion of inorganic arsenic, even at low concentrations, can lead to serious health issues, including skin lesions and an increased risk of various cancers (skin, bladder, lungs). Prolonged exposure has also been linked to cardiovascular disease, diabetes, and neurological effects. Children and pregnant women are particularly vulnerable.
Arsenic enters groundwater through natural processes, like weathering of arsenic-rich rocks and soils. Human activities such as mining, industrial processes, and historical pesticide use also contribute. Private wells are particularly susceptible to arsenic contamination because they lack federal oversight, requiring homeowners to manage their own water quality. Testing is especially relevant if you rely on a private well, live near agricultural or industrial sites, or reside in areas with known natural arsenic deposits.
Home Arsenic Testing Kits
Home arsenic testing kits offer a convenient initial step for screening water quality. These kits typically use a colorimetric method: a water sample is mixed with reagents. The chemicals react with arsenic, causing a color change in a test strip or liquid, which is compared to a color chart to estimate concentration. Some kits may involve generating a gas that interacts with a test strip.
While home kits provide immediate indications of arsenic presence, they have limitations in accuracy and precision. They are screening tools and may not reliably detect or differentiate between all forms of arsenic (arsenite and arsenate). Results can be less precise than laboratory analyses, potentially leading to false positives or negatives. For definitive and accurate results, especially regarding specific arsenic forms and concentrations, professional laboratory testing is recommended.
Professional Laboratory Testing
For the most accurate and comprehensive assessment of arsenic in water, professional laboratory testing is the gold standard. This process typically begins by ordering a test kit from a certified laboratory, which includes specific instructions for collecting a water sample. Adhering to these instructions carefully is essential to ensure the sample’s integrity and the reliability of the results. Once collected, the sample is sent back to the lab for analysis.
Certified laboratories utilize advanced analytical techniques, such as Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and Atomic Absorption Spectrometry (AAS). These methods are highly sensitive and precise, detecting arsenic concentrations down to parts per billion (ppb) levels. Professional testing also distinguishes between arsenite (As3+) and arsenate (As5+), important because their removal methods differ. The comprehensive analysis provided by certified labs offers reliable data for informed decisions about water safety.
Understanding Results and Next Steps
Once professional laboratory test results are received, interpret them in relation to established safety standards. The U.S. Environmental Protection Agency (EPA) has set the maximum contaminant level (MCL) for arsenic in public drinking water at 0.010 mg/L (10 ppb). If your water test results indicate arsenic levels above this 10 ppb threshold, take action to mitigate exposure.
Should arsenic be detected above safe levels, consult with water treatment specialists. Various treatment systems can effectively reduce arsenic concentrations. Common methods include reverse osmosis, adsorption media, and activated alumina filtration, each with its own advantages and maintenance requirements. The specific form of arsenic (As3+ or As5+) can influence treatment effectiveness, highlighting the importance of comprehensive lab results. After installing any treatment system, re-testing the water is important to confirm its effectiveness.