The popularity of sparkling water has brought scrutiny to what is in the beverage beyond water and carbonation. The concern centers on the unintended presence of Per- and Polyfluoroalkyl Substances (PFAS), a group of man-made chemical contaminants. Understanding the nature of these chemicals is important for consumers because they have been detected in various bottled waters, including many sparkling varieties. This article explains what PFAS are, how they enter the water supply, and their potential health implications.
Understanding PFAS: The Forever Chemicals
Per- and Polyfluoroalkyl Substances (PFAS) are a family of thousands of synthetic chemicals, first developed in the 1940s, used widely across industrial and consumer products. The compounds are characterized by an extremely strong chemical bond between carbon and fluorine atoms. This carbon-fluorine bond is one of the most stable in organic chemistry, granting the chemicals exceptional resistance to heat, oil, and water. This chemical stability explains why they were historically favored for use in non-stick cookware, water-repellent fabrics, and certain firefighting foams. Because they persist for decades once released, they have earned the common designation of “forever chemicals.”
How PFAS Enter Drinking Water Sources
PFAS contamination in bottled and sparkling water primarily originates from the source water used by the bottling company. The chemicals are highly mobile, easily traveling through soil to contaminate groundwater and surface water. Major contributors to this environmental release include industrial sites, wastewater treatment plants, and areas where firefighting foam (AFFF) was historically used. Bottled water companies draw from these contaminated sources, and inadequate filtration may fail to remove the persistent chemicals. Studies show that sparkling water products often contain detectable levels of PFAS, sometimes higher than still water, usually due to source water quality rather than the carbonation process itself. The regulation of bottled water falls under the Food and Drug Administration (FDA), which has been slower than the EPA to establish maximum contaminant levels for municipal tap water. This regulatory gap means consumers often rely on independent testing and third-party reports to assess product safety.
Health Concerns Related to PFAS Exposure
The primary concern with PFAS is their ability to accumulate in the human body over time, a process known as bioaccumulation. Once ingested, these chemicals resist excretion and build up in tissues, particularly the blood, liver, and kidneys. Long-term exposure, even to low levels, has been associated with several adverse health outcomes. The chemicals are known to interfere with the endocrine system, which can disrupt the body’s natural hormone function, including that of the thyroid. Exposure has been linked to increased levels of cholesterol in the blood and damage to the liver. Specific PFAS compounds, such as PFOA and PFOS, have also been linked to an increased risk of certain cancers (kidney and testes) and adverse developmental and reproductive outcomes during pregnancy.
Regulatory Standards and Consumer Mitigation
The U.S. Environmental Protection Agency (EPA) previously issued non-enforceable health advisories for PFOA and PFOS. Reflecting growing scientific understanding of their toxicity, the interim lifetime health advisories were dramatically lowered to 0.004 ppt for PFOA and 0.02 ppt for PFOS. In 2024, the EPA finalized Maximum Contaminant Levels (MCLs) for several PFAS, setting an enforceable standard of 4.0 ppt for both PFOA and PFOS in public drinking water. Although the FDA regulates bottled water, some state governments and non-governmental organizations have pushed for stricter limits, often setting standards as low as 1 ppt for bottled products. Consumers seeking to reduce their exposure have several effective options, including prioritizing sparkling water brands that voluntarily publish third-party testing results showing very low PFAS levels.
Filtration Options
For those concerned about their tap water, which can be used to make sparkling water at home, specialized home filtration systems are effective. Reverse osmosis (RO) systems and granular activated carbon (GAC) filters are certified to remove PFAS, offering a practical way to ensure a purer drinking source.