65/ 100
D
OverallF47/100
Field Company Cast Iron Seasoning Oil

Soybean Oil · Cast Iron Cookware Seasoning

Field Company Cast Iron Seasoning Oil

D · Elevated

Lower PFAS concern. Pure soybean oil contains no fluorinated compounds.

Verdict: SkipPure soybean oil seasoning poses minimal chemical hazards; no known contamination or brand safety issues on record.

Soybean oil is a plant-based seasoning with no fluorinated additives or coatings. No PFAS risk from the product itself.

The safe swap

Cast Iron Ultimate Bundle

Coconut Oil

Cast Iron Ultimate Bundle

90/100 safety

A

Same rubric that flunked this product. The swap earned its A.

Still want this one anyway? Check the price on Amazon. We’d swap it.

Material

Soybean oil (plant-based)

Brand disclosure

Brand is silent on PFAS

Lab data

No public lab test

Why this grade

Safe base material

Made from a material with no inherent PFAS use (ceramic, mineral, or natural fiber).

Helps the grade

Category baseline

cookware 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

The full breakdown

What it's made of and why it matters

This product is soybean oil, a plant-derived triglyceride with no synthetic additives or coatings. Soybean oil contains naturally occurring compounds (primarily oleic and linoleic fatty acids) that polymerize when heated, forming a protective seasoning layer on cast iron. Unlike synthetic seasoning products, there are no fluorinated polymers, heavy metal binders, or resin curing agents involved in the formulation.

The brand's record and disclosure

Field Company maintains minimal public disclosure on this product's sourcing or processing beyond identifying it as soybean oil. No recalls, safety warnings, or third-party certifications (organic, non-GMO, or food-grade) are on record for this specific seasoning oil. The brand's general reputation in cast iron maintenance is established, but transparency around ingredient sourcing and refining methods is limited.

How it compares in its category

Soybean oil seasoning is a conventional choice in cookware maintenance, sitting between mineral oil (inert but non-polymerizing) and specialized high-smoke-point oils like grapeseed or avocado oil. It is cheaper and more accessible than certified food-grade alternatives and carries lower heavy metal risk than some vintage seasoning compounds or waxes. The main trade-off is smoke point: soybean oil smokes around 450F, requiring careful temperature control during seasoning application.

If you buy it

Apply thin coats only, using a cloth to wipe away excess oil before heating to avoid sticky buildup or rancid odor. Heat cast iron slowly to moderate temperatures (below 450F) when seasoning to prevent smoking and unpleasant fume release. Store the bottle in a cool, dark place away from direct sunlight to slow oxidation; discard if the oil smells musty or rancid. Reapply seasoning every few months of regular use, or after washing with soap.

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

Oxidation and rancidity over time

Soybean oil is prone to oxidative breakdown, especially if stored in warm, humid conditions or exposed to light. Rancid oil produces off-odors and potentially irritating volatile compounds when heated; discard if smell becomes musty or sour.

Reported

Smoke and fume inhalation during heating

Soybean oil has a relatively low smoke point (around 450F). Heating above this threshold releases acrolein and other volatile aldehydes, which can irritate airways. Use low to moderate heat and ensure ventilation during seasoning.

Possible

Bacterial or mold growth if contaminated

Once opened, soybean oil can accumulate moisture or microbial growth if exposed to air repeatedly or stored improperly. Risk is low with normal storage but increases if the bottle is left uncapped or stored in humid environments.

None known

Pesticide residues in non-organic soybean oil

No specific testing or recalls for this product exist on record. Conventional soybean oil may contain trace pesticide residues common to soy crops, but typical seasoning amounts applied to cookware pose negligible dietary risk.

What we don’t know

This grade is a model-based estimate from public materials, coatings, and brand disclosure at 92% 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 Cast Iron Cookware Seasoning

Cast Iron Ultimate Bundle

Coconut Oil

Cast Iron Ultimate Bundle

cast iron, bare or seasoned with coconut oil

A
B
PFASAll
A · Very low PFAS2 flags

Lower PFAS concern. Bare cast iron is inherently PFAS-free.

Risky category by default

Crisbee Puck Cast Iron Seasoning

Soybean Oil

Crisbee Puck Cast Iron Seasoning

Soybean oil, beeswax blend

B
C
PFASAll
B · Low PFAS2 flags

Lower concern. Traditional seasoning oil without non-stick coatings.

Risky category by default

Carrington Farms Hemp Oil

Hemp Oil

Carrington Farms Hemp Oil

Hemp seed oil, liquid cooking oil

B
C
PFASAll
B · Low PFAS1 flag

Lower concern. Unrefined plant oil has no known PFAS risk.

Risky category by default

More cast iron cookware seasoning 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.