Bisphenol A (BPA) is a chemical compound used to manufacture durable, clear, and rigid plastic products, including the large 5-gallon water jugs historically found on water coolers. The primary concern is that BPA can migrate, or leach, from the plastic container into the drinking water it holds. This chemical migration raises questions about consumer health and safety.
The Direct Answer: Polycarbonate and BPA
The answer to whether all 5-gallon jugs are BPA-free is no, although the industry has largely shifted away from the material. Historically, the most common material for clear, rigid, reusable 5-gallon bottles was Polycarbonate (PC) plastic. Polycarbonate contains Bisphenol A as a foundational component.
When a jug is made of polycarbonate, BPA can leach into the water, a process accelerated by environmental factors. Exposure to heat, such as storage in a hot garage or delivery truck, significantly increases the rate of chemical migration. Repeated use and washing also cause the plastic to break down and release more BPA.
Scientific studies have demonstrated this leaching effect, showing a significant increase in BPA concentration in water stored in polycarbonate bottles exposed to elevated temperatures. BPA is classified as an endocrine-disrupting chemical, meaning it can interfere with the body’s hormonal system by mimicking estrogen.
Identifying BPA Status Using Recycling Codes
Consumers can determine the likelihood of BPA content in their 5-gallon jug by checking the Plastic Identification Code (PIC), often located on the bottom. This code appears as a number inside a small triangle, commonly referred to as the recycling symbol, and reveals the type of plastic resin used.
The most critical code to look for is the number 7, labeled as “Other” or “Miscellaneous.” Polycarbonate plastic, which contains BPA, falls under this broad category. Therefore, a jug marked with a 7 is the strongest indicator that the container likely contains BPA.
For bottles considered BPA-free, consumers should look for codes 1, 2, 4, or 5. These codes indicate the use of materials such as:
- Code 1 (PET or PETE): Polyethylene Terephthalate is a clear plastic used for many single-use bottled water containers and some newer 5-gallon jugs. While BPA-free, it is not designed for the same long-term reuse and durability as the older polycarbonate.
- Code 2 (HDPE): High-Density Polyethylene is a robust, opaque plastic often used for heavy-duty containers like milk jugs. Though less common for clear water jugs, HDPE is a reliable, BPA-free option.
- Code 4 (LDPE) and Code 5 (Polypropylene): These plastics are also BPA-free but are generally not used for the large, clear 5-gallon water bottles.
Alternative Materials for 5-Gallon Water Storage
The market for 5-gallon jugs offers several inherently BPA-free alternatives that maintain durability and clarity. The most common replacement for polycarbonate is Tritan, a type of copolyester. Tritan plastic offers glass-like clarity and high shatter resistance without using BPA.
Tritan is resistant to odor and taste transfer, ensuring the stored water remains pure. Its chemical stability and heat resistance allow it to withstand repeated washing and high-temperature environments better than polycarbonate without leaching chemicals.
Beyond plastic, non-plastic options offer complete assurance of zero chemical leaching. Large glass carboys provide an inert storage option, though they are extremely heavy and fragile. Stainless steel containers are another robust alternative, prized for their durability and total chemical neutrality, though they are opaque and can be more costly.