303 Protectant vs Waterproofing Wax for Leather: which is safer?

Where these two actually differ

• We flag Volatile organic compounds (VOCs) from spray propellant and carriers, Skin and eye irritation from direct contact, Respiratory sensitization or irritation from repeated aerosol exposure and Incomplete biodegradability of polymer film residue on the 303 Protectant and not on the Nikwax.
• We flag Respiratory irritation or fume inhalation during application and PFAS in water repellency treatment on the Nikwax and not on the 303 Protectant.
• The 303 Protectant is UV protectant/water-repellent coating (unspecified polymers) where the Nikwax is wax-based waterproofing, 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 Nikwax is the one to buy.
• We are less certain about the 303 Protectant grade, at 45% confidence against 78%, because it discloses less.