When you drink water directly from a garden hose, the liquid consumed is municipal water that has been treated and contains chlorine. The water entering the hose from your spigot is the same disinfected water flowing to your kitchen sink. However, the hose itself is the source of greater concern, as it introduces a range of chemicals not regulated for human consumption. This addition of contaminants makes drinking directly from a standard garden hose inadvisable.
The Source of the Chlorine
The presence of chlorine in the water is a direct result of the public health practice of water disinfection. Water treatment facilities add chlorine to kill various pathogens, including bacteria, viruses, and parasites that cause waterborne diseases. This chemical treatment has been a standard practice for over a century and has drastically reduced waterborne illnesses.
The chlorine is maintained in the water distribution system as a “residual disinfectant.” This residual amount is a small, monitored concentration that ensures the water remains protected against contamination as it travels through piping. This continuous protection is a primary advantage of chlorine.
Typical residual chlorine levels in drinking water are often below 4 parts per million (ppm), the maximum level set by regulatory agencies like the Environmental Protection Agency (EPA). While this level is safe for drinking, it is the reason you can sometimes smell or taste chlorine, especially if your home is close to a water treatment facility.
Chemical Impact of the Hose Itself
The primary risk in drinking from a hose is not the municipal chlorine, but the chemicals that leach directly from the hose material into the water. Most conventional garden hoses are made from polyvinyl chloride (PVC), which often contains non-food-grade chemical additives. This leaching process is accelerated when the hose is exposed to sunlight or when water is left stagnant inside.
One major concern is the presence of lead, which can leach from the brass fittings or connectors found on many hoses. Studies have detected lead levels in standing hose water that exceed the EPA’s action level of 15 parts per billion (ppb). Other plasticizers, such as phthalates, are common in PVC hoses to make them flexible and durable.
Phthalates are endocrine-disrupting chemicals that can leach into the water. Bisphenol A (BPA), another chemical used in plastics, has also been shown to leach into standing water, with tested levels as high as 87 ppb. These contaminants accumulate in the water trapped inside the hose, particularly on hot days.
The water sitting inside a hot hose can contain high concentrations of these compounds. Furthermore, the hose material is not regulated by the same drinking water standards that govern the pipes inside your house, making it a source of unregulated chemical exposure.
Practical Steps for Safe Hose Water Use
To minimize the risk of chemical exposure, the first step is to flush the hose thoroughly before use. Running the water for 30 seconds to a few minutes will clear the stagnant water that has absorbed leached chemicals and is often warmer than the fresh supply. This action removes the water that has been sitting in contact with the hose material.
When purchasing a new hose, look for products specifically labeled as “drinking water safe” or “food-grade.” These hoses are constructed from materials like polyurethane or high-quality rubber, manufactured without lead, BPA, or phthalates. While they may cost more, they significantly reduce the potential for chemical leaching compared to standard PVC hoses.
Storing your hose in a shaded area or coiling it out of direct sunlight will reduce the temperature inside the hose, slowing down the chemical leaching process. For applications where chlorine may be undesirable, such as watering sensitive plants, you can mitigate the residual chlorine by filling a bucket and letting it sit uncovered for a few hours. This exposure to air allows the chlorine to naturally off-gas from the water.