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Bottled vs. Tap Water. Warm-Up. How many disposable Plastic water bottles (PWBs) do you use in a week (average) What % of the PWBs you use do you recycle? For what reasons do you use PWBs over tap water? (convenience, fear of tap, mom makes me…). Why bottled?. Convenience
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Warm-Up • How many disposable Plastic water bottles (PWBs) do you use in a week (average) • What % of the PWBs you use do you recycle? • For what reasons do you use PWBs over tap water? (convenience, fear of tap, mom makes me…)
Why bottled? • Convenience • Health- “it’s better than soda!” • Tap is less desirable • “It tastes funny” • I’m scared • Wells can have high mineral content • Iron- “blood” taste • Sulfur- “rotten eggs”
The Facts • Historically, bottled water are helpful in emergencies and in areas where clean water is unavailable • Pollution events, Natural Disasters • PWB usage in the US has increased 70% since 2001 • Americans drank 33 billion L of bottled water in 2007 • It takes 3 L of water to package 1 L of bottled water
Analysis Are tap and bottled so different?
Poland Spring “Born Better” • Sources: Aquifers in Maine • Poland Spring- Poland Spring, ME • Evergreen Spring- Freyburg, ME • Spruce Spring- Pierce Pond Twp, ME • Garden Spring- Poland, ME • Bradbury Spring- Kingfield, ME • Cold Spring- Denmark, ME
Consumer Investigation • Nestle “Pure Life” customer hotline • Sources: “Deep protected well Breinigsville, PA and/or Public Water Supply, Allentown, PA. Purified using reverse osmosis or distillation and enhanced with a balance of minerals for taste” • Contains: Purified water, calcium chloride, sodium bicarbonate, magnesium sulfate
Kirkland- Purified Drinking Water • Processed by advanced filtration, ozone, and reverse osmosis technologies • Ingredients: Purified Water, Potassium Bicarbonate, Sodium Bicarbonate, Calcium Citrate, Sodium Chloride, Magnesium Oxide • “All are food grade chemicals used purely for taste” • Customer Service- Municipal Water supply from Allentown, PA • 12 plants across country • 3 plants use well water (Ontario, CA, FL)
What they put back in… • Calcium Chloride (CaCl2)- road salt • Sodium Bicarbonate (NaHCO3)- baking soda • Magnesium Sulfate (MgSO4)- electrolyte • Water sourced from deep well: • Minerals are removed • Water is treated, or “purified” • Minerals added back in
The Energy Costs • Plastic is made from oil, a fossil fuel • 0.33% of total US energy use is from production of PWBs (17 million barrels of oil) • Energy required to make 1 L of bottled water = 8 million Joules • Indirect energy usage- packaging, transportation, refrigeration
Economic Costs • Tap water = $0.01 / gallon • Bottled Water = $0.89 / gallon • PWB sales in U.S. • 56% spring water (Poland Spring) • 44% filtered tap water (Aquafina, Dasani)
Tap Water (municipal) Regulated by the EPA Safe Drinking Water Act Multiple daily tests for pathogens and contaminants Results are made available to public Bottled Water Food & Drug Administration (FDA) Weekly tests for water quality Test results do not have to be made public Is it healthier?
Is it healthier? • Chemicals have been known to leak into the water from plastic from • Overuse of the bottle • Left in hot car or in direct sunlight for too long • Bisphenol-A (BPA): affects endocrine system • As of yet, there is has not been proven to be a link between using PWBs and cancer
Solid Waste Concern • Only 23% of PWBs are recycled in the U.S. • 8% of total plastic waste was recovered for recycling in 2011 • The bottles that are NOT recycled end up • Landfills • Litter • Plastic takes >1000 years to biodegrade
Bring Back the Tap! • Reusable water bottles • BPA free plastic “Nalgene” bottles • Stainless steel or aluminum • Glass • Home water filters • Faucet filters • Pitcher filters
Blind Taste Test 4 water samples - 3 bottled - 1 tap • Taste Ranking • 1 = best taste • 4 = worst taste • Matching • Fiji • Poland Spring • Aquafina • Livingston Tap
Bottled v. Tap- Math Practice • Show your work, box your answers • Graded on accuracy • Significant Figures- 3 (11.26443 11.3) • Use Scientific Notation when appropriate • 5.7 million = 5.7 x 106 • 47.2 billion = 4.72 x 1010