Water bottle

Single-use plastic water bottles

Water bottle sales have increased almost every decade in the United States for more than a decade. In 2011, greater than $11 billion was spent on U.S. bottled water products.^[1] The International Bottled Water Association (IBWA) states that Americans are increasingly relying on water bottles for convenience and portability.

Multi-use water bottles can be made from high-density polyethylene (HDPE), low-density polyethylene (LDPE), copolyester or polypropylene. All offer the advantage of being durable, lightweight, dishwasher-safe and BPA-free. The main difference between each type of water bottle is the flexibility of the material. Copolyester and polypropylene bottles offer the greatest rigidity. HDPE bottles retain some flexibility, while LDPE bottles (most commonly associated with 'squeeze' type bottles) are highly flexible and collapsible.

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  Disposable water bottles
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  Multi-use HDPE water bottles
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  One gallon PETE water bottle with attached package handle

Metal water bottles

Metal water bottles

Metal water bottles are growing in popularity. Made primarily from stainless steel or aluminum, they are durable and retain minimal odor or taste from previous contents. Aluminum bottles often contain a plastic resin or epoxy liner to protect contents from taste and odor transfer.^[2] Although most liners are now BPA-free, older and less expensive models can contain BPA.

It is not recommended to fill aluminum bottles with acidic liquids (e.g. orange juice), as this could cause aluminum to leach into the contents of the bottle.^[3] Stainless steel bottles do not contain a liner but have been known to transfer a metallic taste and odor to contents. Bottles made with food grade stainless steel (Grade 304, also known as 18/8) do not transfer taste or odor. Depending on the type of source material and manufacturing process behind your stainless steel bottle, trace amounts of minerals can leach into contents.^[4]

Metal water bottles can be heavier than their plastic counterparts and readily transfer temperature of contents to external surfaces, which makes them unsuitable for use with unusually hot or cold liquids. Double-walled stainless steel bottles are insulated to keep cold liquids cold and hot liquids hot, without the external surface being too hot or too cold. Because double-walled bottles have more stainless steel in them, they are more expensive.

Glass water bottles

Glass water bottle with protective silicone sleeve

Because they are completely recyclable, BPA free and transfer minimal taste or odor, glass water bottles are becoming a popular choice for many consumers worried about their health.

Heavier than plastic, stainless steel or aluminum bottles, they are easier to damage and break. Glass bottles have a high level of temperature transfer, so they are not ideal for very hot or cold liquids.^[5]

Filtering water bottles

Carbon filtering water bottle.

This type of bottle is often BPA-Free and more commonly uses carbon (activated charcoal) filtration. UV light can also be used to purify water. UV filtration bottles are popular and convenient for those who are traveling to areas where water quality may be harmful, or where bottled water is not readily available. UV is effective against all water-borne pathogens.^[6]

Carbon filtration bottles will eliminate some organic chemicals and improve the taste and odor of water. Carbon filtration will not eliminate pathogens, metals or nitrates from water.^[7] Carbon filters must be changed regularly to maintain effectiveness.

Connected water bottles

Connected devices collect data related to a person's water intake. The data is transmitted to a smartphone, which enables tracking of an individual's water intake and alerts the user when they are not properly hydrated. These devices are a result of recent technology advancements which fall and the broader category of the Internet of Things. Devices that monitor and collect data related to one's personal health are also part of the Quantified Self movement. While several concepts have been introduced, none are currently available commercially.

Hydration reservoirs

Hydration reservoir

Hydration reservoirs, also known as ‘hydration bladders,’ are large volume, flexible bags typically carried in a backpack system. Users access water via a 'sipping tube.' This system allows the user to remain engaged in activity without having to stop and unscrew a water bottle.^[8]

Health

Chemicals used for making some types of bottles have been shown to be detrimental to the health of humans. Inhalation of chemicals used in the manufacture of plastics is a hazard for the factory workers who handle the material. In many developing countries, plastic waste is burned rather than recycled or deposited in landfills. Rural residents of developing countries who burn plastic as a disposal method are not protected from the chemical inhalation hazards associated with this practice. Inhalation of the pollutants produced from burning plastics have been shown to result in poor health outcomes.^[11] It is important to dispose of water that has been stored in PET bottles beyond the expiration date because harmful chemicals may leach from the plastic.^[12]

Bottle manufacturing relies on fossil fuels and natural resources. Some manufacturing processes release toxic chemicals into the air and water supply that can adversely affect nervous systems, blood, kidneys, immune systems, and can cause cancer and birth defects.^[12] Most disposable water bottles are made from petroleum derived polyethylene terephthalate (PET). While PET is considered less toxic than many other types of plastic, the Berkeley Ecology Center found that manufacturing PET generates toxic emissions in the form of nickel, ethylbenzene, ethylene oxide and benzene at levels 100 times higher than those created to make the same amount of glass.^[13]

Research is ongoing as to whether plastic water bottles can leach hazardous chemicals into the water, especially when heated.^[11]

Environment

Label on disposable water bottle highlighting positive environmental attributes.

Water bottles made of glass, aluminium and steel are the most readily recyclable. HDPE and LDPE bottles can be recycled as well.

Because the manufacturing and transportation of disposable water bottles requires petroleum, a non-renewable resource, the single-serve bottled water industry has come under pressure from concerned consumers. The Pacific Institute calculates that it required about 17 million barrels of oil to make the disposable plastic bottles for single-serve water that Americans consumed in 2006. To sustain the consumptive use of products relying on plastic components and level of manufactured demand for plastic water bottles,^[14] the end result is shortages of fossil fuels. Furthermore, it means not only a shortage of the raw materials to make plastics, but also a shortage of the energy required to fuel their production.^[15]

In recent years, the single-serve bottled water industry has responded to consumer concern about the environmental impact of disposable water bottles by significantly reducing the amount of plastic used in bottles.^[16] The reduced plastic content also results in a lower weight product that uses less energy to transport. Other bottle manufacturing companies are experimenting with alternative materials such as corn starch to make new bottles that are more readily biodegradable.

The lowest impact water bottles are those made of glass or metal. They are not made from petroleum and are easily recyclable. By choosing to continuously fill any multi-use water bottle, the consumer keeps disposable bottles out of the waste stream and minimizes environmental impact.