What is the most sanitary type of water bottle long-term?

Long-term sanitation determines what is the most sanitary type of water bottle:

• Material Degradation:
  • Plastic: Scratches harbor bacteria increasingly
  • Glass: Micro-cracks accumulate contamination
  • Medical Steel: Maintains original properties
• Sanitation Over Time:
  • Year 1: All materials relatively clean
  • Year 2: Plastic 10x more bacteria
  • Year 5: Only steel maintains sanitation
• Cost Analysis:
  • Replacing contaminated bottles yearly
  • Vs. one lifetime sanitary bottle
  • Health costs from contamination
• Testing Results:
  • 10-year-old medical steel: Like new
  • Antimicrobial properties unchanged
  • Surface integrity maintained

For lifetime sanitation, medical steel is what is the most sanitary type of water bottle.