Is there a difference between tap, bottle, and filtered water?

Dear Reader and Thirsty, 

Tap, bottled, filtered—are they all aqua-lly good for you? The answer ultimately boils down to personal choice and your individual hydration needs. Some people may prefer to drink bottled water because of taste preferences, convenience, or a lack of access to clean and safe tap water. Tap water in New York City, however, is considered safe to drink and may even have an edge on bottled water (more on this in a bit). If you have access to clean and safe tap water, filters aren’t essential but can help improve the taste and smell of your water. On the other hand, if your water contains harmful contaminants or if you have certain health conditions, filters might be beneficial or even necessary. 

Many American tap water supplies contain fluoride, a mineral which is typically added at processing plants before it flows through your faucet. Fluoride helps to prevent cavities by strengthening the surface, otherwise known as the enamel, of the tooth. Consistent exposure to low levels of fluoride in drinking water helps to keep tooth decay at bay and promotes oral health in general, especially among children with developing teeth. However, ingesting highly elevated levels of fluoride may lead to conditions like dental fluorosis or skeletal fluorosis. If you live in the United States (US), you can check out My Water’s Fluoride to learn more about the amount of fluoride in your tap water. Of note, bottled water may also contain fluoride depending on the source of the water. However, manufacturers of bottled water aren’t required to disclose the amount of fluoride on the bottle. 

Worldwide, studies have found that microplastics are more abundant in bottled water compared to tap water, especially in PET (polyethylene terephthalate) bottles. Microplastics are small plastic fragments less than five millimeters (about 0.2 inches) in length. They are formed when plastic waste breaks down due to microbes, exposure to ultraviolet (UV) light, or weather elements. While more research is needed to fully understand the toxicity of microplastics, studies on human cells in the lab have found that they can trigger inflammation and damage lipids, proteins, and DNA in cells. Opening and closing, carrying, and squeezing bottles are all forms of mechanical stress that can contribute to microplastic contamination. Even in glass bottles, plastic packaging such as plastic layers under the cap can release microplastics. In contrast, microplastics may be less prevalent in tap water because water treatment plants remove a significant amount of them. 

As for tap water in the Big Apple, most of the city’s water supply comes from reservoirs and lakes found in the Catskill Mountains. Water that comes from the Catskills isn’t filtered due to its high quality, but it is disinfected with chlorine and UV light to kill germs and potentially harmful microorganisms. The city also takes additional measures to reduce exposure to metals like lead. They also provide additional tips for reducing lead exposure. Among these tips is the recommendations to not use hot water for drinking or preparing formula because lead dissolves more easily in hot water. 

Tap water in New York City must adhere to standards of quality set by the Environmental Protection Agency (EPA) under requirement of the Safe Drinking Water Act (SWDA), SWDA limits the level of contaminants acceptable in drinking water. In other words, tap water in the city that never sleeps is safe to sip straight from the spigot (now say that three times fast!). 

Even if tap water is safe to drink, some people may still choose to use water filters for various reasons. For instance, activated carbon filters—commonly found in refrigerators and pitcher filters—are primarily used to improve the taste of water by reducing unpleasant tastes and odors. They may also reduce metals like lead and copper, cleaning solvents, and pesticides. However, activated carbon filters may not remove bacteria and other harmful contaminants that can’t be smelled or tasted such as volatile organic compounds (VOCs). If you decide to use a water filtration system, it’s recommended that you read the label on your filter to check if it’s certified by the National Sanitation Foundation (NSF). If it is, you can search the NSF database to find out what it’s certified to protect you against. 

In some cases, water filters or other water treatment systems may be recommended for certain groups of people. These include people who: 

• Are immunocompromised 
• Use tap water for nasal rinsing 
• Have lead in their drinking water 
• Have arsenic in their drinking water 
• Have nitrates in their well water 
• Have hard water (water that has high levels of mineral content) 

Whether tap, bottled, or filtered water is best for you ultimately depends on what’s in your water and what you want out of it! Still looking to quench your thirst for more information on water? Consider doing a simple internet search for “water quality” in your specific geographic region to learn more. 

Cheers,