Glass Meal Prep Set vs Flex Seal 28-pc. Food Storage Set: which is safer?
Pyrex Glass Meal Prep Set is our pick: better on PFAS and on the overall hazard picture.
Our pick
Pyrex
Glass Meal Prep Set
PFAS grade
Excellent 95/100
Overall grade
Good 71/100
Verdict
Buy
Hazard flags
⚑ 3
Material
borosilicate glass with metal lids (likely stainless steel or aluminum)
Confidence
92%
PossibleMetal lid corrosion and leaching
ReportedSilicone or rubber gasket degradation
ReportedThermal shock fracture from glass
Rubbermaid
Flex Seal 28-pc. Food Storage Set
PFAS grade
Good 70/100
Overall grade
Good 52/100
Verdict
Buy
Hazard flags
⚑ 3
Material
Polypropylene (PP) plastic lids and containers
Confidence
72%
PossibleMicroplastic generation from wear
PossibleOligomer leaching under heat or lipid contact
ReportedLid seal degradation
Where these two actually differ
- We flag Metal lid corrosion and leaching, Silicone or rubber gasket degradation and Thermal shock fracture from glass on the Pyrex and not on the Rubbermaid.
- We flag Microplastic generation from wear, Oligomer leaching under heat or lipid contact and Lid seal degradation on the Rubbermaid and not on the Pyrex.
- The Pyrex is borosilicate glass with metal lids (likely stainless steel or aluminum) where the Rubbermaid is Polypropylene (PP) plastic lids and containers, which is most of the difference in these two grades.
- The gap is 25 points, wide enough that this is not a close call, and the Pyrex is the one to buy.
Both products run through the same public rubric: materials, coatings, brand disclosure, lab findings, and recalls, plus a beyond-PFAS hazard analysis. Grades are model-based estimates, not lab tests. How grades work →
More food storage containers: see the full ranking