Make Your Own Water Pollution Tester At Home

Water pollution is a pressing issue, with freshwater habitats across the globe in a state of crisis. Testing water quality is essential to monitor progress towards Sustainable Development Goal 6 (SDG6), which calls for universal and equitable access to safe and affordable drinking water by 2030. While commercial water testing products are available, they can be costly and inaccessible to some. Low-tech water quality testing methods are an area of active research, with new options being developed regularly. This introduction will discuss various approaches to making a water pollution tester, from simple, low-cost methods to more advanced testing kits.

Testing for nitrates and phosphates

Nitrates and phosphates are essential nutrients for plant growth. However, excessive amounts can lead to water pollution, affecting aquatic life and human health. Therefore, regular testing is crucial for maintaining water quality and protecting aquatic ecosystems from the detrimental effects of pollution. Here are some methods and considerations for testing nitrate and phosphate levels:

Testing Methods:

• Colorimetric Techniques: This method uses colour comparison to determine nitrate and phosphate concentrations. Test kits, such as the Kyoritsu tubes, contain reagents that react with the samples, changing colour based on the nitrate or phosphate levels. The higher the concentration, the darker the colour.
• Ion Chromatography: This technique separates and identifies ions in the water sample, allowing for the measurement of nitrate and phosphate levels.
• Field Test Kit: These kits are inexpensive and convenient for detecting inorganic forms of nitrogen, including nitrate, nitrite, and ammonium. They are typically in the form of test strips that provide relatively accurate results compared to commercial laboratory analysis.
• Spectrophotometer: A more expensive option, a spectrophotometer reads the absorbance of the sample to determine nitrate levels.
• Nitrate Electrode and Meter: This method measures nitrate activity in the water by detecting changes in the electric potential of the solution, which is then converted to nitrate concentration.

Sampling Considerations:

• Sample Collection: Collect water samples from streams or rivers, being careful not to scrape the bottom if the water is shallow. Clearly label each sample, especially if you are testing the same water source at different locations.
• Timing: Plan your sampling based on external factors such as fertilisation schedules, rainfall, and water flow. These factors can impact nitrate and phosphate levels in the water.
• Storage and Testing: Samples can be refrigerated and tested within 24 hours, but for the most accurate results, test the samples on-site or as soon as possible. If not testing immediately, swirl the contents to ensure even mixing.
• Comparison and Interpretation: Compare your test results against local water quality standards and regulations to assess the extent of pollution and determine any necessary corrective actions.

Health and Safety:

Nitrates and phosphates can have significant health impacts, especially on infants and young children. High nitrate levels in drinking water can lead to Blue Baby Syndrome in infants, affecting their ability to carry oxygen in the blood. Elevated nitrate levels have also been linked to potential long-term health effects, including a possible increased risk of non-Hodgkin's lymphoma in older children and adults. Therefore, regular testing of drinking water sources, especially in vulnerable areas, is crucial to ensure the safety of your community.

Using a turbidity tube

A turbidity tube is a simple, low-tech device used to measure the turbidity of a water sample. Turbidity refers to the cloudiness or haziness of a fluid, which is caused by particles of varying sizes scattering or absorbing light. These particles can include dirt, sand, clay, silt, algae, or other debris. High levels of turbidity can affect the aesthetic appearance of water and may also have health implications, so it is important to monitor turbidity levels, especially in drinking water.

To use a turbidity tube, follow these steps:

• Holding the tube upright and keeping it out of direct sunlight, look vertically down into the tube.
• Gradually pour in the water sample that you want to test, filling the tube up to the top without introducing any air bubbles. Make sure to collect the water sample directly from the source to ensure accuracy.
• Stop pouring just before the black and white pattern at the bottom of the tube becomes invisible. This pattern is typically a black cross or a black marker on the side of the tube, indicating the water's turbidity level in Nephelometric Turbidity Units (NTU).
• Observe the turbidity level by looking at the black marker or scale on the side of the tube. The higher the turbidity level, the more suspended particles are present in the water, making it appear cloudier or murkier.
• Record the results, including the turbidity level observed for the water sample.
• To ensure accuracy, allow the water to settle for a few minutes before repeating steps 3 to 5. This step helps any suspended particles settle at the bottom of the tube, providing a clearer reading.

By using a turbidity tube, you can visually assess the clarity of water and determine the presence of suspended particles. However, it is important to note that turbidity tubes may not provide precise measurements for very low turbidity levels and rely on the user's consistent judgment. For more accurate measurements, optoelectronic meters can be used, which emit a known intensity of light through the sample to determine turbidity.

Testing for colour, taste, and odour

To test for colour, you can compare your water sample to a distilled water sample. If your water appears cloudy, this could be due to turbidity, which is a term used to describe a lack of transparency in water caused by tiny particles that reflect light, reducing clarity. To test for the water's true colour, these particles must first be removed. This can be done by allowing the water to settle, and then testing the colour of the clearer water. The colour of water can indicate the presence of undesirable and potentially harmful materials, such as organic matter, or harmless constituents such as tannins, iron, and manganese. To determine the exact cause of the colour change, a chemical test kit or handheld colourimeter can be used.

To test for odour, you can again compare your water sample to a distilled water sample. If your water has an unpleasant odour, this could be harmless or it could be harmful. To determine the exact cause of the odour, a package test is required.

To test for taste, you can compare your water to a distilled water sample. A salty taste could indicate a high level of total dissolved solids, while a metallic taste could be caused by zinc.

If you are concerned about the quality of your water, it is recommended to proceed to Level 2 Testing, which involves using a DIY testing kit to confirm your observations. If your results indicate the presence of a contaminant, you can then proceed to Level 3 Testing, which involves working with a water professional to certify your results.

Using a commercial water testing kit

Commercial water testing kits are a great way to test the quality of water in your local rivers, lakes, and streams. These kits are designed to be user-friendly and provide accurate information about the water's safety and potential health risks. Here is a step-by-step guide on how to use a commercial water testing kit:

Choosing a Kit:

Firstly, select a reputable water testing kit that suits your needs. Popular options include the Tap Score, WaterCheck CityCheck Deluxe, and Safe Home Ultimate Drinking Water Test Kit. These kits vary in price and features, so it is essential to research which kit aligns with your specific requirements.

Collecting the Sample:

Follow the instructions provided with your chosen kit to collect a water sample. This typically involves filling a sterile container with the water you want to test. Ensure that you collect the sample from an appropriate location, such as a local river, stream, or lake, and follow any specific guidelines provided by the kit manufacturer.

Testing the Sample:

Depending on the kit you choose, you might need to send your sample to a certified lab for testing. Other kits, like the Kyoritsu tubes, allow you to test the water sample yourself. For example, to measure nitrates and phosphates, you add fresh water samples to the tubes, and after a few minutes, the water changes colour, indicating the concentration of nitrogen or phosphorus present. The higher the concentration of these nutrients, the darker the colour.

Interpreting the Results:

Once the test is complete, carefully interpret the results. Look for colour changes or other indicators specified in the kit's instructions. Different kits will provide varying levels of detail in their results. For example, the Tap Score kit offers plain language explanations of the compounds found in the water, their potential health risks, and suggestions to address any concerns. Other kits may use colour-coding or icons to indicate contaminant levels.

Taking Action:

Finally, based on the test results, you can take appropriate action to improve water quality or address any potential health risks. This could include installing filters, advocating for better water treatment practices, or participating in initiatives like the Great UK WaterBlitz, which aims to build a national picture of water quality.

By following these steps and using a commercial water testing kit, you can play a vital role in monitoring water quality and ensuring safe and healthy freshwater ecosystems.

Testing for bacteria

Testing for Coliform Bacteria:

Coliform bacteria are commonly found in the intestines of warm-blooded animals, including humans, farm animals, pets, and wildlife. Faecal coliform bacteria, including E. coli, are a specific type of coliform that can indicate the presence of harmful contaminants in the water. To test for coliform bacteria, you can use a water testing kit, such as the Test Assured Home Inspection Water Test Kit or the Tap Score Advanced City Water Test. These kits can detect the presence of coliform bacteria and provide a comprehensive report on the potential health risks associated with your water source.

Understanding E. coli:

Escherichia coli (E. coli) bacteria are a large group, and most types are harmless and naturally present in the gut. However, certain strains of E. coli can cause serious illnesses. Testing for E. coli can be challenging, as it is present in all warm-blooded animals, making it difficult to pinpoint the source of contamination. Nevertheless, a positive test for E. coli indicates the presence of faecal matter and potential harmful germs in the water.

Testing Methods:

Water testing kits are widely available and offer a convenient way to test for bacteria. These kits typically include sampling bottles and instructions for collecting water samples, which are then sent to accredited laboratories for analysis. Some kits, like the Tap Score, provide detailed reports and online support to help interpret the results. Alternatively, you can contact your local health department or a state-certified laboratory for guidance on testing and interpreting results, especially if you suspect the presence of harmful bacteria or contaminants.

Indicators of Bacteria:

While testing for specific bacteria is essential, there are also indirect ways to assess the presence of bacteria. For example, testing for nutrient pollution, such as high levels of nitrates and phosphates, can indicate potential bacterial growth. Nutrient pollution can lead to a process called eutrophication, where excessive plant and algal growth creates favourable conditions for bacterial proliferation, reducing oxygen levels and harming aquatic life.

Preventing Bacteria:

To prevent bacterial contamination, it is crucial to understand the potential sources of pollution. This includes identifying the water source, whether it is a public or private system, and the surrounding environmental factors. Regular testing, at least once a year as recommended by the CDC, is essential to detect any issues early on and ensure the safety of your water supply.

By following these instructions and staying vigilant, you can effectively test for bacteria in your water supply and take the necessary steps to ensure safe and healthy water for yourself and your community.

Frequently asked questions