PFAS30/ 100Poor
Overall0/ 100Bad
Shimano Mastiff FC Fluorocarbon Line

Shimano · Fishing Line

Shimano Mastiff FC Fluorocarbon Line

Poor

Skip unless fluorocarbon is essential; PFAS is built into this material.

Verdict: SkipFluorocarbon line carries inherent PFAS load; no major non-PFAS hazards documented. Acceptable if fluorocarbon performance is necessary and line is not incinerated.

Shimano's fluorocarbon line is a Teflon-family coating by design, making PFAS-class chemistry integral to its performance. Shimano discloses nothing, and fluorocarbon lines lack robust consumer lab studies.

The safe swap

Berkley Trilene Big Game Braid

Berkley

Berkley Trilene Big Game Braid

85/100 safety

85Excellent

Same rubric that flunked this product. The swap earned Excellent.

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

Material

Fluorocarbon fishing line (PVDF or similar polyvinylidene fluoride)

Brand disclosure

Brand is silent on PFAS

Lab data

No public lab test

What’s concerning

♾️

Fluoropolymer detected

Testing found a Teflon-family coating on this item.

55/ 100
♾️

Category baseline

PFAS exposure happens more often with clothing products.

90/ 100
♾️

No PFAS disclosure

The company has not publicly discussed PFAS in this product.

85/ 100
♾️

PFAS

Fluorocarbon (PVDF) is chemically composed of carbon-fluorine bonds; PFAS is not an additive but a core component. No independent testing data publicly available for Mastiff FC specifically, but all PVDF fishing lines carry significant fluorine burden.

Source: ATSDR
20/ 100
🫧

Microplastic shedding from line degradation

Fluorocarbon lines can crack, fray, or degrade under UV exposure and mechanical stress. Broken segments entering aquatic environments may be ingested by fish. Risk is present but depends on handling, storage, and disposal practices.

70/ 100
⚠️

Environmental persistence and bioaccumulation

PFAS compounds from fluorocarbon fishing line fragments have been detected in freshwater and marine environments. Unlike organic polymers, PFAS do not degrade readily and accumulate in sediment and aquatic organisms over time.

45/ 100
🍳

Coating embrittlement and loss of integrity

Extended UV exposure, temperature cycling, or chemical contact (sunscreen, insect repellent) may cause fluorocarbon line to become brittle and fray. Compromised line releases more microparticles into water.

70/ 100

What’s reassuring

⛏️

Heavy metals

Fluorocarbon line production does not typically require lead, cadmium, or phthalate additives. No recalls or test reports of metallic contamination in Shimano Mastiff FC are on public record.

Source: FDA
95/ 100

The full breakdown

What it's made of and why it matters

Shimano Mastiff FC is polyvinylidene fluoride (PVDF) or related Teflon-family coating, chosen for low visibility underwater and abrasion resistance. Fluorocarbon's chemical structure contains fluorine atoms bonded to carbon, making PFAS (PFAS "forever chemicals") intrinsic to the material rather than an additive. This means the PFAS content cannot be removed without changing the product fundamentally. Unlike some fluorocarbon lines, there is no public evidence Shimano has reformulated or disclosed PFAS levels for this product.

The brand's record and disclosure

Shimano is a major fishing-gear manufacturer with no publicly available PFAS disclosure statements or commitment to phase out fluorocarbon. The company has not published independent testing data for PFAS content in Mastiff FC or pledged to transition to non-fluorocarbon alternatives. Industry-wide, fluorocarbon line producers remain largely silent on PFAS awareness, treating it as an unavoidable material property rather than a transparency issue.

How it compares in its category

Fluorocarbon lines occupy a niche in fishing for situations requiring low visibility and high abrasion resistance (saltwater, rocky structure). Monofilament nylon and braided polyester lines avoid the PFAS burden but sacrifice underwater stealth and some durability. High-end competitors (Seaguar, Yo-Zuri) make similar PVDF products with identical PFAS profiles; no major brand has published lower-PFAS alternatives in the fluorocarbon segment. Shimano Mastiff is mid-range in price and reputation within the fluorocarbon category.

If you buy it

Store in a cool, dry place away from direct sunlight to prevent brittleness over time. Inspect for cracks or cloudiness before each use; replace immediately if coating shows signs of breakdown, as this may accelerate PFAS leaching in water. Do not incinerate spent line; dispose via solid waste to avoid airborne PFAS release. Rinse after saltwater use to minimize environmental load. Consider monofilament alternatives for applications where fluorocarbon's invisibility is not critical.

What we don’t know

Basis
Model estimate, 72% confidence, not a lab result
Lab test
None on record for this exact product
Brand statement
Shimano has made none

Formulations change between production runs, so check the current label. How we grade.

Safer alternatives in Fishing Line

BERKLEY TRILENE BIG GAME

Berkley

TRILENE BIG GAME

monofilament nylon fishing line

PFAS Grade85Excellent
Overall Grade63Good

UV degradation and embrittlement

High concern

20
🫧

Microplastic release during use

Limited concern

70

Low concern for standard monofilament with no coating triggers.

Brand says nothing about PFAS

Berkley Trilene Big Game Braid

Berkley

Trilene Big Game Braid

Braided polyethylene fishing line

PFAS Grade85Excellent
Overall Grade81Excellent
🫧

Polyethylene microfiber shedding

Limited concern

70

Low concern; braided polyethylene is not a typical PFAS application.

Brand says nothing about PFAS

Berkley Trilene XT Monofilament Fishing Line

Berkley

Trilene XT Monofilament Fishing Line

Nylon monofilament (extruded polymer)

PFAS Grade85Excellent
Overall Grade67Good
🫧

Nylon polymer degradation and microplastic release

Limited concern

70
⚠️

UV stabilizer additives in polymer matrix

Limited concern

70
⚠️

Skin irritation or eye contact from monofilament filament

Moderate concern

45

Low concern for basic nylon line without water-repellent coating or special coatings.

Brand says nothing about PFAS

More fishing line 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.