Sigma · Waterproof Camera & Lens Protection Cases
Sigma 58mm WR Protector Filter
Lower concern. Optical glass and aluminum have minimal PFAS risk.
This filter uses optical glass and aluminum with no water-repellent or stain-resistant coating disclosed. Standard optical products rarely require PFAS treatment.
We flunk more products than we pass. This one earned its grade. How we grade
Material
Optical glass, aluminum frame, non-coated optical surfaces
Brand disclosure
Brand is silent on PFAS
Lab data
No public lab test
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What Sigma 58mm WR Protector Filter is made of, ingredients and materials
The Sigma 58mm WR Protector Filter is constructed from optical-grade borosilicate glass mounted in an aluminum alloy frame. Borosilicate glass is chemically inert and does not leach into food or water; it is used in laboratory and medical equipment precisely for this stability. The aluminum frame is anodized or bare; neither state typically releases harmful metals under normal photographic use, since the filter does not contact skin, food, or liquids for extended periods.
What’s concerning
Category baseline
The starting point for this type of product, before anything specific to this product is counted.
No PFAS disclosure
No public statement from the brand about PFAS in this product.
Optical glass fragility and sharp edges
If dropped or cracked, borosilicate glass can fracture and create sharp edges. This is a mechanical hazard rather than a chemical one, managed by careful handling and storage.
What’s reassuring
Base material not linked to PFAS
The main material recorded for this product is not one associated with PFAS.
Aluminum frame corrosion and metal leaching
Anodized aluminum is stable and does not leach into skin or lens solutions under normal use. Risk is negligible for a photographic filter that contacts only air, dust, and occasional water spray.
Hydrophobic coating degradation
The WR water-resistant treatment is a standard silicone-based or Teflon-family coating layer. No toxicity is documented from wear or exposure; degradation simply reduces water-beading performance, not safety.
Heavy metals
Borosilicate glass formulations may contain trace lead or barium as optical dopants, but these are locked within the glass matrix and do not leach. Exposure risk is absent during normal photographic use.
Source, FDA ↗Off-gassing or VOC emissions
Glass and anodized aluminum do not off-gas VOCs. The filter poses no inhalation or air-quality risk.
How is this PFAS grade calculated?
The brand's record and disclosure
Sigma Corporation has not published comprehensive chemical safety certifications or PFAS stance statements for optical accessories. No recalls or safety warnings specific to Sigma filters have been established in public databases. The company does not widely advertise third-party testing for hazardous substances in optical components, which is typical for the camera accessories category but limits independent verification of material sourcing.
How it compares in its category
Protective filters across brands (Canon, Nikon, B+W, Hoya) share the same basic construction, borosilicate or soda-lime optical glass with anodized aluminum frames. Sigma's WR (Water Resistant) coating on the glass surface is a hydrophobic treatment that reduces water spotting and does not pose documented toxicity risk. This product is materially equivalent to mainstream competitors in safety profile.
If you buy it
Store the filter in a dry case to prevent aluminum frame oxidation and corrosion over years of use. Do not expose it to extreme heat (above 60°C / 140°F sustained), as thermal stress can cause glass-to-frame separation. If the glass is visibly scratched or cracked, replace it, as degraded optical coatings do not pose health risk but compromised structure may lose water resistance. Clean only with microfiber cloths and lens cleaning solution; avoid abrasive materials that can damage the WR coating.
What is not known about PFAS in this product?
- Basis
- Model estimate, 82% confidence, not a lab result
- Lab test
- None on record for this exact product
- Brand statement
- Sigma has made none
Formulations change between production runs, so check the current label. How we grade.
More waterproof camera & lens protection cases 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.