True. Indeed, the popular belief that we should avoid drinking hot water directly from the tap seems to be founded on the truth. Here are a few reasons:
Although tap water does not generally contain lead, this metal can contaminate your water supply if the plumbing in your home is corroded. Furthermore, hot water dissolves contaminants, including lead, faster than cold water does. This heavy metal can affect the brain and nervous system, particularly in young children. However, environmental scientists maintain that the risk remains very low. To be on the safe side, you should use cold water when preparing baby formula and cooking food, as well as for drinking.
To prevent burns that can be attributed to very hot tap water, we should lower the temperature of our water heater. In doing this however, we risk encouraging the development of harmful bacteria, because even at 60°C – the setting on most electric water heaters – it is estimated that a quarter of all water heaters are contaminated by legionella bacteria. Proliferating at the bottom of water heaters where temperatures are lower, these bacteria are responsible for a type of pneumonia that is usually contracted by inhaling contaminated droplets of water emerging from, for example, whirlpools and hot tubs, showers and central air conditioning systems found in large buildings. It is estimated that close to 100 individuals are hospitalized each year in Quebec for this type of pneumonia.
To lower your risk of having to contend with these problems, Hydro-Quebec recommends that you control the maximum hot water temperature by installing appropriate mixing control valves, either at the outlet of your water heater, or at the faucets. This will allow you to keep your hot water at a higher temperature in the water heater, but at a temperature that is more secure at the faucets. Hydro-Quebec also recommends you purchase a high-temperature, stainless steel electric water heater which will prevent the proliferation of potentially harmful bacteria.