Citat:A. It depends on the type of plastic you want to use. Some plastics are more resilient than others.

B. Along the same lines, we don't really know which bottles are safer or whether the variable acidity of nicotine-based eliquids will leech components from the plastic bottle.

C. Speaking of leeching; we don’t know where those plastic bottles have come from and what’s in them. Some of the biggest concerns with consumables going into reused plastics are Bisphenol A (BPA), Styrene and Phthalates.

• Bisphenol A (BPA) has a hormone-like effect and at high levels can affect brain and reproductive development in animal studies. Human studies are lacking, but there is suspicion in the scientific community that high levels of bisphenol A can affect humans. (source material here)
  
• Styrene is a compound that causes oxidative damage to tissues and DNA. Styrene has been associated with hearing loss and nervous system diseases in humans. There may also be an association between styrene exposure and the development of pancreatic cancer. (source material here)
  
• Phthalates are another group of chemicals that mimic hormones. Phthalates are associated with lower sperm counts, DNA damage to sperm, male infertility, and developmental and reproductive abnormalities. (source material here)
  

D. Other big concerns; it depends on how long that bottle has been used, what's been used in it, what it has been cleaned with (detergents can lead to the breakdown of plastics) and what it's made of. A lot of plastic bottles are made with polyethylene terephthalate (PET) which is difficult to completely clean and is rather porous. Bacteria can easily grow on the surface of PET containers, especially after it is covered with liquid film. While PET is rather durable, it can begin to degrade, particularly after being exposed to heat, sunlight, or prolonged use. If the company actually manufactured it as a biodegradable plastic container then that could lead to other issues – as these are designed to break down easier and again we don’t know how these types of container plastics react to nicotine-based eliquids. (some source material on plastics and biodegradation)

Depending on where you got the bottle and if the manufacturer used good practices in the production process, there should be a PIC code on the bottle. Sometimes found within the Recycling triangle on the bottom of bottles or it may just be shown as a number.


Here’s a run down of PIC codes to help you identify what is generally regarded as safe (GRAS) for reuse (depending on application of course – some don’t apply to how we typically store eliquid)

#1 Polyethylene terephthalate (PET, PETE), typically found in soft drink and water bottles. It is important to recycle these containers after their initial use, mostly due to the risk for bacterial growth from reuse after improper cleaning. This type of plastic is generally more porous which affords bacteria a good place to hide. These containers can begin to degrade with prolonged use, exposure to excessive heat, ultraviolet light from the sun, and high pressure.

#2 High Density Polyethylene (HDPE), typically found in milk, juice, and reusable water bottles. This plastic is considered safe and can be reused with cool liquids. Heat, bleach, and strong detergents can damage the plastic which can lead to break-down of the containers.

#3 Polyvinyl chloride (V or PVC), typically found in juice bottles. Phthalates are used to soften this type of plastic, and certain containers can leach phthalates with prolonged or inappropriate usage.

#4 Low Density Polyethylene (LDPE), typically found in squeeze bottle, flexible container lids, and squeeze-bottles. This plastic is considered safe if used properly.

#5 Polypropylene (PP), typically found in reusable, microwaveable containers, kitchenware, and margarine tubs. This plastic is considered safe if used properly.

#6 Polystyrene (PS), typically found in egg cartons, Styrofoam cups, and take-home containers. This plastic can release styrene... but you’re probably not going to put your eliquid into a Chinese takeout box or foam carton so I wouldn’t worry too much about this one.

#7 Other, including Lexan and polycarbonate (PC) containers. Polycarbonate plastic is used in baby bottles and some water bottles. It is a hard plastic that resists stains and flavors. Polycarbonate plastic (Lexan) releases bisphenol A. Polycarbonate plastic will release more bisphenol A when exposed to hot liquids, chemicals, or strong detergents.

The most appropriate containers for eliquid would likely fall into PIC 2 or 4, but again keep in mind that we (our industry) don’t have enough research or data to state whether or not specific plastics – even low density polyethylene squeeze bottles – are safe to use with eliquid.

With all that said, be cautious even if you’re just storing some eliquid in a plastic container for day to day use. Be conscious of the age of the container, where it comes from, and what it’s made of. If you do use them, recycle them frequently and start fresh instead of washing them with detergents for continued reuse.