An Investigation into the Effects of Temperature and Storage Time on Military Packaged Water in Afghanistan - The Liberation and Migration of Potential Contaminants from Expeditionary Water Packaging System Polyethylene Terephthalate Water Bottles
Abstract:
Expeditionary Water Packaging Systems EWPS transfer treated drinking water e.g., Reverse Osmosis Water Purification Unit ROWPU into polyethylene terephthalate PET plastic bottles on-site to provide greater versatility in battlefield potable water distribution operations. As these systems continue to enter military inventories, questions have arisen regarding PET bottle degradation of chemical and aesthetic drinking water characteristics with extended storage at elevated temperatures. To elucidate the impact of bottled water storage practices on water quality, PET bottles produced in Afghanistan and filled with in-country ROWPU produced water were exposed at 23.5, 37.7, 48.8, and 60 degrees Celsius for 7, 14 or 28 days. Physiochemical water quality results showed limited contaminants migrating from the PET packaging despite the harsh exposure conditions. Antimony was detected at one half the regulatory limits at the 28 day mark at 60oC. Limited total organic carbon and volatile organic compounds disinfection byproducts were also detected. Other trace contaminants, such as orthophthalates, likely migrated from water treatment or bottling apparatuses prior to bottling as they were detected in similar concentrations in the treated water. The aesthetic quality of the bottled water was negatively impacted by heat and prolonged storage Threshold Odor Number TON values elevated above 3 TON over time in each of the exposure conditions. This is the first EWPS quantitative assessment of possible chemical exposure related to PET bottle degradation due to storage at elevated temperatures. Results have direct relevance to TBMED577 bottled water storage and physiochemical testing guidelines as well as deployment occupational environmental health exposures.