80/ 100
B
OverallC72/100
Glasslock Oven Safe Rectangle 6pc set

Glasslock · Food Storage Containers

Glasslock Oven Safe Rectangle 6pc set

B · Low PFAS

Lower-concern buy; glass food containers don't require PFAS-based coatings.

Verdict: BuyBorosilicate glass eliminates leaching risks; stainless steel lids are chemically inert. No established safety issues reported for this product line.

Glasslock's oven-safe glass containers are made from borosilicate glass, which is an inherently inert material with no known PFAS application. Glass does not require non-stick, waterproofing, or grease-resistant treatments to function, so PFAS exposure from this product is unlikely.

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Material

borosilicate glass with stainless steel lids

Brand disclosure

Brand is silent on PFAS

Lab data

No public lab test

Why this grade

Category baseline

food packaging is a category where PFAS exposure is more common.

Hurts the grade

No PFAS disclosure

No public statement about PFAS in this product.

Hurts the grade

Uncoated safe material

Bare, uncoated material (cast iron, stainless, carbon steel, or glass) with no surface treatment to contain PFAS.

Helps the grade

The full breakdown

What it's made of and why it matters

Glasslock containers use borosilicate glass, a type specifically engineered to resist thermal stress and chemical leaching. The lids are stainless steel, which does not leach metals or chemicals into food under normal use. Unlike ceramic or plastic food storage, borosilicate glass has no polymeric coating that can degrade, no glaze that may contain lead, and no risk of microplastic shedding when heated or microwaved. This material combination is chemically stable across a wide temperature range.

The brand's record and disclosure

Glasslock does not publicly disclose PFAS testing results or a dedicated PFAS-free stance, placing them in the silent majority on this issue. However, no product recalls or safety violations are on record for this borosilicate line. The brand markets the containers as oven-safe and BPA-free, acknowledging basic consumer safety expectations. Independent laboratory testing of similar borosilicate glass products has found no PFAS or heavy metal contamination, though Glasslock has not independently verified this.

How it compares in its category

Glass food storage containers avoid the primary hazards of plastic alternatives (BPA, phthalates, leaching). Compared to ceramic or metal containers, borosilicate glass is chemically more transparent and carries no glaze contamination risk. The stainless steel lid is preferable to plastic or silicone lids, which can degrade over time and shed particles. In its category, this product design is among the safest options available.

If you buy it

Borosilicate glass is microwave, oven, and dishwasher safe up to the manufacturer's stated temperature (typically 400F for this line). Replace lids if silicone seals crack or become discolored, as degraded seals reduce airtightness. Do not subject glass to sudden extreme temperature changes (e.g., moving from freezer to hot oven), as thermal shock can cause breakage. Hand wash lids occasionally to extend seal life and prevent mineral buildup around threads.

Beyond PFAS: other things we checked

Established hazard classes for this product type, assessed from public information. These never change the PFAS grade; a Likely flag caps the Verdict at “Buy with care.”

Possible

Thermal breakage risk

While borosilicate glass is more resistant to thermal shock than soda-lime glass, sudden temperature extremes (freezer to direct heat) can still cause cracking or shattering. Follow manufacturer guidance on temperature transitions.

Possible

Stainless steel lid degradation

Silicone gasket seals may degrade over years of repeated dishwasher cycles or exposure to acidic foods. Degraded seals compromise airtightness but do not leach toxic substances; lids can be replaced individually.

None known

BPA or phthalates in lid gasket

Glasslock markets these containers as BPA-free; no reports of BPA, BPS, or phthalate contamination in the silicone or stainless steel lids. Material composition of gaskets is not disclosed in detail.

None known

Lead or cadmium in glass

Borosilicate glass used in food storage containers does not require lead-based flux or cadmium colorants. No recalls or contamination reports exist for this product line.

None known

Microplastic or coating shedding

Borosilicate glass has no polymeric coating to degrade. Stainless steel lids do not shed microplastics. This design eliminates a major hazard of plastic storage alternatives.

What we don’t know

This grade is a model-based estimate from public materials, coatings, and brand disclosure at 85% confidence. It is not a lab result.

No independent PFAS lab test is on record for this exact product. A lab test could move the score in either direction.

The brand has not made a specific, verifiable PFAS-free statement, so part of this score reflects that missing disclosure rather than a confirmed material.

Formulations and coatings change between production runs. Always check the current label before buying.

Safer alternatives in Food Storage Containers

Caraway Food Storage Set

Caraway

Food Storage Set

Glass containers with plastic lids

A
B
PFASAll
A · Very low PFAS3 flags

Lower concern; glass + plastic lids with stated PFAS-free position, but no third-party verification of lid material.

Risky category by default

Caraway Home 9-Piece Mini Food Storage Set

Caraway

Home 9-Piece Mini Food Storage Set

Borosilicate glass containers with plastic lids

A
B
PFASAll
A · Very low PFAS3 flags

Lower-concern option; glass containers avoid PFAS coatings, but verify lid material before purchase.

Risky category by default

Caraway Cream 6.6-Cup Non-Stick Glass Food Storage Container with Lid

Caraway

Cream 6.6-Cup Non-Stick Glass Food Storage Container with Lid

borosilicate glass with non-PFAS lid

A
B
PFASAll
A · Very low PFAS4 flags

Lower PFAS concern, glass container with stated non-PFAS lid, though third-party verification absent.

Risky category by default

More food storage containers grades

How we score: every product runs through the same public 0–100 rubric based on materials, coatings, brand disclosure, lab findings, and recalls. See the full methodology → Spotted a mistake? Report an error.