Storing water in plastic containers is a common practice for many households, whether preparing for emergencies or managing daily water needs. Understanding the characteristics of plastic containers and factors affecting water quality over time can help ensure a safe water supply.
Understanding Plastic Containers for Water Storage
Different types of plastic are commonly used for water storage, each identified by a recycling code. Polyethylene Terephthalate (PET or PETE), marked with #1, is frequently used for disposable water bottles. High-Density Polyethylene (HDPE), identified by #2, is often found in milk jugs and detergent bottles, and is considered one of the safer plastics for water storage due to its durability and resistance to degradation. Polypropylene (PP), with #5, is another suitable option for reusable containers.
HDPE is robust and less prone to leaching. Conversely, Polyvinyl Chloride (PVC, #3) and Polystyrene (PS, #6) are generally not recommended for water storage due to concerns about potential chemical leaching. Selecting food-grade containers ensures they are made from materials deemed safe for contact with consumables.
Factors Influencing Water Storage Duration
Several environmental and container-related factors influence how long water can be safely stored in plastic. Warmer conditions accelerate plastic degradation and increase chemical leaching. Storing water in a consistently cool environment helps preserve both the container’s integrity and the water’s quality.
Direct sunlight can degrade plastic and promote algae growth. Opaque or UV-resistant containers block light and maintain water purity. Minimizing air exposure by filling containers completely helps prevent microbial growth and odor absorption. The initial cleanliness of the container and water source is paramount, as existing contaminants can multiply during storage.
Potential Considerations with Stored Water in Plastic
Concerns regarding water stored in plastic containers primarily revolve around chemical migration and microplastics. Chemical leaching, where substances from the plastic transfer into the water, is a recognized consideration. Compounds such as Bisphenol A (BPA) and phthalates have been associated with certain plastics, though many modern containers are “BPA-free.” Other chemicals can still migrate, particularly when plastic is exposed to heat or undergoes repeated use.
Microplastics also present a consideration. Tiny plastic particles can shed from containers into the water, and their long-term health effects are being researched. Adhering to best storage practices can significantly mitigate potential risks.
Best Practices for Safe Water Storage
Implementing best practices for water storage in plastic containers can maximize safety and extend shelf life. Select appropriate food-grade containers, often opaque and durable, to minimize light exposure and prevent physical damage. New containers are preferable, as previously used containers may retain residues that could contaminate water.
Before filling, thoroughly clean containers with soap and water, then sanitize them using a solution of one teaspoon of unscented household chlorine bleach mixed with one quart of water. Pour out the solution. When filling, leave minimal air space at the top to reduce microbial growth and chemical absorption. Store filled containers in a cool, dark, and dry location, away from direct sunlight, chemicals, or strong odors. Rotate stored water every six months to one year, labeling containers with the storage date.
Signs That Stored Water May Not Be Safe
Identifying signs that stored water may no longer be safe to consume is important. Visual cues include cloudiness, discoloration such as brown, yellow, or rust-colored tints, or visible particles and algae.
Unusual odors are another strong indicator. Water that smells musty, chemical, metallic, or like rotten eggs (sulfur) should be viewed with caution. Bitter or metallic flavors suggest the water may be compromised. If any of these signs are present, discard the water.