Non-Toxic Food Storage Containers: What to Look For

The food storage container market is full of products that claim to be safe, natural, and free from harmful chemicals. The reality is more complicated. Most plastics used in food containers are technically safe under normal use conditions, but not all plastics are equal, and the differences matter particularly for people who use their containers daily, heat food in them, or store acidic or fatty foods that interact more aggressively with plastic surfaces.

Here is what the science actually says, and what to look for when choosing non-toxic food storage containers.

The chemicals worth understanding

BPA (Bisphenol A)
BPA is a chemical used in the production of polycarbonate plastic and epoxy resins. It has been linked to hormonal disruption because it mimics estrogen in the body. Most reputable food container manufacturers have removed BPA from their products, and most modern containers labeled as food-safe are BPA-free. However, BPA-free does not automatically mean the product is free of all potentially concerning compounds.

BPS and BPF
When manufacturers removed BPA, many replaced it with structurally similar compounds including BPS (bisphenol S) and BPF (bisphenol F). Early research suggests these alternatives may have similar hormonal activity to BPA. The science is still developing, but consumers who are concerned about BPA exposure should be aware that BPA-free does not guarantee freedom from related compounds.

Phthalates
Phthalates are plasticizers added to PVC and some other plastics to make them flexible. They are also endocrine disruptors and have been linked to reproductive health concerns in animal studies. Phthalates are more commonly found in flexible plastic products than in rigid food storage containers, but they are worth being aware of when evaluating any plastic product.

Chemical migration and leaching
Plastics can leach small amounts of chemical compounds into food, particularly under certain conditions: high temperatures (microwave use, hot dishwasher cycles), acidic foods (tomatoes, citrus, vinegar-based dressings), and fatty foods (oils, cheese, meat). The rate of leaching increases with heat, acidity, and fat content.

The safest materials for food storage

Tritan copolyester
Tritan is a copolyester plastic developed by Eastman Chemical. It is manufactured without BPA, BPS, or phthalates and has been independently tested for estrogenic and androgenic activity — the hormonal disruption mechanisms associated with BPA and its alternatives. Multiple independent studies have found no detectable hormonal activity from Tritan under standard and stress-test conditions.

The Silo container set uses Baby Bottle Grade Tritan, the highest food safety standard applied to Tritan products. Baby bottle-grade certification requires the material to meet the strictest chemical migration standards, making it one of the most thoroughly tested food contact plastics available.

Glass
Glass is chemically inert. It does not leach any compounds into food under any conditions, including high heat, acidic foods, and fatty foods. From a chemical safety perspective, glass is the gold standard for food storage. The trade-offs are weight and breakability.

Stainless steel
Food-grade stainless steel (typically 18/8 or 304 stainless) is also chemically inert and does not leach compounds into food under normal storage conditions. The limitation is that it is not microwave-safe and not transparent.

Standard polypropylene (PP)
Polypropylene is the most common plastic used in food containers. It is BPA-free in its modern form and considered food-safe by the FDA. It does not contain phthalates. However, it is not as thoroughly tested for all potential chemical migration as Tritan, and it absorbs odors and stains over time more readily than Tritan or glass, which indicates greater surface interaction with food.

Plastics to avoid

Polycarbonate (PC)
The original source of BPA concern in food containers. While many manufacturers have transitioned away from polycarbonate, older containers and some imported products may still use it. Check for the recycling code 7 on the bottom of containers — this includes polycarbonate and a range of other plastics.

PVC (Polyvinyl chloride)
PVC may contain phthalate plasticizers and should be avoided for food storage. It is rarely used in rigid food containers but appears in some food wraps and flexible packaging.

What to look for on labels and certifications

FDA compliance
In the United States, food contact materials must comply with FDA regulations on chemical migration. FDA-compliant materials have been tested and approved for food contact use at specified conditions.

Independent testing
The most reassuring products are those that have been independently tested by third-party laboratories for chemical migration and hormonal activity, not just by the manufacturer. Tritan's safety profile has been established through independent testing by multiple external laboratories.

Temperature ratings
Check the stated temperature range for any container. A material that is food-safe at room temperature may behave differently under repeated microwave or dishwasher exposure. Tritan containers are rated for microwave use (lid removed) and dishwasher use, and have been tested under these stress conditions.

Practical guidance for everyday use

Regardless of the material you choose, a few practices reduce chemical exposure from any food container:

• Do not microwave food in containers not rated for microwave use
• Replace containers that are scratched, cloudy, or show signs of degradation — surface damage increases the potential for chemical migration
• Avoid storing hot food directly in plastic containers — allow food to cool before transferring
• For acidic or fatty foods that will be stored long-term, glass or Tritan are preferable to standard polypropylene

FAQ

Is BPA-free the same as non-toxic?
No. BPA-free means the product does not contain bisphenol A, but it may contain structurally similar compounds like BPS or BPF. The most thoroughly tested option for chemical safety is Tritan copolyester, which has been independently tested for all major hormonal activity pathways, not just BPA.

Are glass containers always the safest choice?
From a chemical safety perspective, yes. Glass is chemically inert and does not leach anything into food under any conditions. The practical trade-offs are weight and breakability. For households where these trade-offs are acceptable, glass is the safest choice.

How do I know if my current containers are safe?
Check the recycling code on the bottom. Code 7 includes polycarbonate and other mixed plastics — avoid these for food storage if possible. Codes 2, 4, and 5 are generally considered safer choices. Tritan is coded as 7 but is significantly different in composition from polycarbonate — look for explicit Tritan labeling rather than relying on the recycling code alone.

Non-toxic food storage is not complicated once you understand what to look for. Tritan and glass are the two strongest choices for everyday use. The Silo container set uses Baby Bottle Grade Tritan throughout, independently tested for chemical safety and built for daily use across all temperature conditions. Shop the Silo Container Set.