Chrono 42 Quartz Watch vs Runner Cardio GPS Watch: which is safer?
Swatch Chrono 42 Quartz Watch is the clear pick. TomTom Runner Cardio GPS Watch carries a failing PFAS grade, and we never recommend buying a failing product.
Our pick
Swatch
Chrono 42 Quartz Watch
PFAS grade
Overall grade
Verdict
Hazard flags
Material
Confidence
PossibleMineral crystal breakage and laceration
PossibleBattery chemical leakage (internal only)
TomTom
Runner Cardio GPS Watch
PFAS grade
Overall grade
Verdict
Hazard flags
Material
Confidence
PossibleUndisclosed waterproofing chemistry (likely fluorinated compounds)
PossibleElastomer band degradation and skin contact
PossibleMicroplastic release from band wear
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 waterproof smartwatches & fitness trackers: see the full ranking