You should never store olive oil in a plastic bottle. Plastic packaging and olive oil are a genuinely bad combination. Research consistently shows that plastic leaches phthalates and BPA into the oil. And the longer the oil sits in plastic, the worse the contamination gets.
This is not fringe science. It is peer-reviewed, published in major food science journals, and the findings are consistent. Here is what the science actually says.
What Happens When Olive Oil Sits in Plastic
Plastic containers — particularly PET (polyethylene terephthalate) and PVC — contain chemical compounds called phthalates. Phthalates are plasticizers added to plastic since the 1930s to make it flexible, durable, and extensible. The critical problem is that phthalates do not form stable chemical bonds with the polymers they are added to. Phthalates sit loosely within the plastic matrix. And this makes them susceptible to migrating into whatever the plastic is in contact with.
Olive oil is particularly vulnerable because phthalates are lipophilic. Which means they dissolve readily in fats and oils but have very low solubility in water. So when a fatty food like olive oil comes into contact with plastic, phthalates move from the plastic container walls into the oil at a much higher rate than they would into a water-based product. The migration accelerates significantly under heat, UV light exposure, and prolonged storage — exactly the conditions a bottle of olive oil on a grocery store shelf or kitchen counter experiences every day.
What the Research Found
Based on articles from PubMed and independent food science research, multiple independent studies have now documented phthalate contamination in commercially sold olive oil.
A study analyzing olive oil samples from the European market found that DEHP and DINP — two of the most common and concerning phthalates — were detected in all samples tested. With average concentrations of 1.31 and 1.52 mg/kg, respectively. Four out of sixteen samples showed DEHP concentrations exceeding the migration limits established under EU food contact materials regulation. Three of those four samples were extra virgin or virgin olive oils — the highest grade products, which consumers reasonably expect to be the cleanest.
A separate study tracking plasticizer contamination across the entire olive oil production process found that concentrations progressively increased at each stage. From the olive fruit itself through processing and into packaging. Crucially, while glass and plastic bottles showed similar contamination levels at six months, plastic-packaged samples showed significantly higher plasticizer concentrations after 18 months of storage. The researchers concluded that prolonged storage in plastic bottles should be avoided.
A third study on phthalate occurrence in foods confirmed that olive oil's contribution to overall dietary phthalate exposure is relevant given how frequently and generously it is used, and that contamination can occur at multiple points in the production and storage chain — not just from the final packaging.
Bisphenol A (BPA) Is Also a Concern
Phthalates are not the only chemical compound that migrates from plastic into olive oil. A study examining BPA migration from plastic packaging into extra virgin olive oil found BPA levels above the daily intake limits set by the European Food Safety Authority in olive oil stored in both polycarbonate (PC) and polyethylene (PE) plastic bottles — reaching 0.238 ppm in PC bottles and 0.144 ppm in PE bottles.
BPA is a known endocrine disruptor. Even at low levels, it interferes with hormonal signaling. The EFSA has set its tolerable daily intake at 0.2 nanograms per kilogram of body weight per day — an extremely low threshold that reflects how seriously regulators take even trace exposure.
Why Olive Oil Is Especially Vulnerable
Not all foods are equally affected by plastic packaging. What makes olive oil particularly susceptible is its fat content. Phthalates and BPA are both lipophilic. Which means they preferentially dissolve into fatty substances. The higher the fat content of a food, the more readily these compounds migrate from plastic into it.
Olive oil is essentially pure fat. There is no water content to dilute or slow the migration process. Combined with the fact that olive oil is often stored for months before being used, and that bottles are frequently left near heat sources in the kitchen, the conditions for chemical migration are essentially ideal. Migration is further accelerated by acidic environments, high temperatures, sunlight exposure, and long-term storage. All of which a plastic bottle of olive oil regularly encounters between the producer, the distributor, grocery store shelf, and your kitchen counter.
Beyond phthalates and BPA, microplastic particles themselves have also been detected in olive oil stored in plastic. Which adds a further layer of concern to plastic packaging.
What About the Squeeze Bottle Trend?
If you have been on food social media recently, you have seen the olive oil squeeze bottle — a soft plastic bottle designed for easy pouring. The convenience is real. But from a chemical safety and quality standpoint, squeeze bottles compound every problem with standard plastic.
First, most squeeze bottles are made from soft, flexible plastic. These are exactly the type that requires the highest concentration of plasticizers to achieve that flexibility. More plasticizer content means higher migration potential into the oil. Second, squeeze bottles work by compressing and releasing. Every time air re-enters the bottle, it introduces oxygen — one of the primary drivers of olive oil oxidation. This progressively degrades both flavor and polyphenol content. The antioxidants and anti-inflammatory compounds that make extra virgin olive oil nutritionally valuable are among the first things to degrade when oil is repeatedly exposed to oxygen. Third, most squeeze bottles are clear or lightly tinted. This means the oil inside is exposed to light, another major driver of oxidation and polyphenol loss.
The squeeze bottle solves one problem (convenience) while creating three others (chemical migration, oxidation, and light exposure). It is not a trade-off worth making. If you want easy pouring, transfer a small amount from your dark glass bottle into a ceramic or stainless steel pourer for daily use.
What Plastic Does to Olive Oil Quality Beyond Chemistry
The chemical contamination issue is serious on its own. But plastic packaging also degrades olive oil quality in ways that are measurable at the product level.
Research analyzing commercial olive oils across multiple packaging types found that a sample of extra virgin olive oil packaged in PET plastic exceeded the K270 oxidation limit for extra virgin classification. Which means the oil had oxidized to the point where it legally should have been classified as lampante, the lowest grade, unfit for direct consumption. It was labeled and sold as extra virgin.
This is not an isolated finding. The mislabeling problem in the olive oil industry is well documented, and plastic packaging that accelerates oxidation is one of the factors that contributes to oils degrading below their labeled grade before they ever reach a consumer.
Why Dark Glass Is the Right Choice
Glass is chemically inert. It does not leach compounds into the oil it contains. It does not interact with the acidity of olive oil. And it does not accelerate under heat. A glass bottle of olive oil sitting in the same conditions as a plastic bottle will not contaminate its contents with plasticizers, BPA, or any other migrating compound. There is simply no migration pathway.
Dark glass adds another layer of protection. UV light degrades polyphenols and accelerates oxidation — the same process that turns a fresh, peppery oil flat and stale. Dark glass blocks UV light significantly, extending the window during which the oil remains at peak quality. Read our full packaging comparison: glass vs. plastic vs. tin.
This is why every bottle of EXAU olive oil is packaged in dark, heavy glass. Each bottle weighs approximately two pounds. It is the right container for a product we have spent a year farming and producing carefully. Putting it in plastic would undermine everything that happens before it reaches you.
We also ship directly from our temperature-controlled warehouse in the US. No distributor split, no months under fluorescent lights in a grocery store. The oil travels from our family's groves in Calabria to our US storage facility, where it is held in controlled conditions until it ships to your door. The supply chain is where most olive oil loses its quality. Dark glass and direct-to-consumer shipping are how we protect what we make.
What to Do With the Plastic Bottle You Already Have
If you currently have olive oil in a plastic bottle at home, use it up quickly. Do not store it for months. Keep it away from heat and direct light. And when you replace it, choose dark glass. For guidance on keeping any olive oil fresh once you have it home, read our complete guide to storing extra virgin olive oil.
Frequently Asked Questions
Is it safe to store olive oil in plastic?
Short-term storage in food-grade plastic is unlikely to cause immediate harm, but research consistently shows that phthalates and BPA migrate from plastic into olive oil over time, particularly under heat and light. Prolonged storage in plastic should be avoided.
What type of bottle is best for olive oil?
Dark glass is the gold standard. It is chemically inert, does not leach compounds into the oil, and blocks UV light that degrades polyphenols and accelerates oxidation. Read our full container comparison here.
Are squeeze bottles bad for olive oil?
Yes, for three reasons. Most squeeze bottles are made from soft plastic with high plasticizer content. They allow air back into the bottle each time you use them, progressively oxidizing the oil. And they are typically clear, offering no UV protection. All three problems compound each other.
What are phthalates and why are they in olive oil?
Phthalates are chemical plasticizers added to plastic to make it flexible. They are not chemically bonded to the plastic, so they migrate into fatty foods like olive oil that contact plastic containers. They are known endocrine disruptors and are regulated in the EU due to health concerns.
Does BPA get into olive oil from plastic bottles?
Yes. Research has found BPA levels above EFSA daily intake limits in olive oil stored in both polycarbonate and polyethylene plastic bottles. BPA is a known endocrine disruptor. Dark glass eliminates this risk entirely.
How does plastic affect olive oil shelf life?
Plastic accelerates both chemical contamination and oxidation, meaning the oil degrades faster and may drop below its labeled grade before you ever open it. Read our full guide on olive oil shelf life and how to tell when it has gone bad.
Shop our 100% Italian extra virgin olive oil, bottled in heavy dark glass, shipped direct from Calabria.
We wrote a book called The Olive Oil Enthusiast. Order your copy today.
You May Also Like:
Microplastics in Olive Oil: What the Research Actually Says
Olive Oil Packaging: Glass vs. Plastic vs. Tin
How to Store Extra Virgin Olive Oil: 5 Rules to Keep It Fresh
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