Is there any difference between drinking bottled purified spring water and filtered purified tap water (other than cost)?

 The primary difference between drinking bottled purified spring water and filtered purified tap water, beyond cost, involves their source, processing methods, and taste. Bottled spring water originates from a natural spring, which can impart unique mineral compositions and flavors not found in tap water, while filtered tap water's quality and taste largely depend on the local water supply and the effectiveness of the filtration system used, which can vary widely. Both are typically subject to safety and quality regulations, although the specifics can differ by country or region. Environmentally, consuming filtered tap water tends to have a lower ecological footprint compared to bottled water, due to reduced plastic waste and energy consumption associated with packaging and transportation. 

The comparison between bottled purified spring water and filtered purified tap water extends beyond mere cost considerations to encompass source, processing, environmental impact, and health implications. Bottled spring water is sourced from natural springs, which are often located in protected areas to ensure purity. The water from these springs undergoes minimal processing, aimed at preserving the natural minerals that contribute to its taste and nutritional profile. On the other hand, filtered purified tap water comes from municipal sources, including rivers, lakes, or reservoirs. It is treated extensively to meet safety standards, which includes removing contaminants as well as potentially beneficial minerals. The filtration systems used at home further purify this water, with the sophistication of these systems varying greatly in their ability to remove different types of contaminants.

From a processing perspective, bottled spring water must adhere to specific standards to maintain its "spring water" label, including being collected at the source or through a borehole tapping the underground formation feeding the spring. Purification, if any, aims to maintain the water's natural properties, possibly including UV treatment or filtration to remove particles without significantly altering its mineral content. In contrast, municipal tap water undergoes rigorous treatment processes including coagulation, sedimentation, filtration, and disinfection with chemicals like chlorine or chloramines to eliminate pathogens and contaminants. Home filtration systems can then strip away residual disinfectants and any remaining particulates, potentially also reducing the water's hardness.

Environmentally, the differences are stark. The production and disposal of plastic bottles for spring water contribute significantly to environmental degradation, including increased carbon footprint and plastic pollution. Even when bottles are recycled, the energy used in the bottling and distribution processes has a considerable environmental impact. Conversely, filtered tap water consumed within one's own home substantially reduces these concerns. The use of reusable containers with tap water minimizes waste and energy consumption associated with transportation and packaging of bottled water.

On the health front, both bottled spring water and filtered tap water are generally safe and can meet an individual's hydration needs. The choice between the two might come down to personal preference for taste and convenience, or specific health considerations such as the need for or avoidance of certain minerals. However, it's important for consumers to research their local tap water quality and the efficacy of their home filtration system, as well as to consider the environmental impact of their choices. Ultimately, while both options provide hydration, the differences in source, treatment, environmental impact, and potential health benefits should inform an individual's decision.