The chemistry behind this blind spot is central to understanding why TFA has flown under the radar for so long. Most people have heard of perfluorooctanoic acid and perfluorooctanesulfonic acid because these compounds have been the focus of regulations and water testing for years, but TFA is fundamentally different, explained Siwei Gu, a postdoctoral researcher in NJIT’s Emerging Contaminants Research Laboratory and lead author of the study. TFA is much smaller in molecular size, highly soluble in water, and does not bind strongly to many filter materials that work well for capturing traditional PFAS. Those properties matter enormously in practice. Standard analytical methods and standard treatment trains were engineered around larger molecules that interact readily with activated carbon and ion-exchange resins, so the smallest members of the PFAS family can slip through both the instruments and the treatment barriers that were designed to stop their larger relatives.

To investigate these often-overlooked compounds, the research team analyzed 113 samples in total, including 70 tap-water samples drawn from communities across New Jersey and 43 commercially available bottled beverages purchased for the study. Using a specialized laboratory method capable of measuring compounds that conventional testing procedures struggle to detect, they screened for five ultra-short-chain PFAS. TFA was by far the most frequently detected compound, appearing in 64 of the 70 tap-water samples and in 34 of the 43 bottled beverages. Although concentrations varied geographically, at least one tap-water sample from every single New Jersey county contained detectable levels of TFA, meaning that no corner of the state was entirely free of the compound in the samples collected.

The concentrations the team measured provide a useful quantitative picture of exposure. Among tap-water samples with detectable TFA, the median concentration was 352 nanograms per liter, with higher county averages observed in several northern and northeastern counties, including Essex, Hudson and Bergen. The highest TFA concentration detected in any New Jersey tap-water sample was 1,360 nanograms per liter. Those figures alone would have made the study noteworthy, but the bottled-beverage results proved even more striking and, by the researchers’ own account, unexpected. We anticipated finding trifluoroacetic acid in drinking water, as previous studies in Europe had reported its widespread occurrence, said Arjun Venkatesan, associate professor of civil and environmental engineering at NJIT and director of the Emerging Contaminants Research Laboratory. However, what surprised us was how frequently it was detected, occurring in 64 of the 70 tap-water samples collected across New Jersey and 34 of the 43 bottled beverages analyzed.

The most notable finding involved the considerable differences between plain bottled water and beverages containing added ingredients. Among the 43 bottled beverages tested, the 12 formulated beverages, meaning products with ingredients beyond water, had an average TFA concentration approximately 52 times higher than the 31 plain bottled waters. Concentrations in some electrolyte waters and sports drinks were particularly elevated, with the highest single measurement reaching 94,100 nanograms per liter, a figure that dwarfs the 1,360 nanograms per liter maximum recorded in New Jersey tap water. That roughly seventy-fold gap between the most contaminated tap sample and the most contaminated beverage raises an obvious and uncomfortable question: if the water going into these products is not the primary source of the TFA, what is?

The researchers have not yet determined why some formulated beverages contained substantially higher concentrations than plain bottled water. Unlike plain bottled water, these products may include sweeteners, flavorings, electrolytes and other additives that could introduce additional sources of TFA into the finished product. One possible explanation is that ingredients used in these beverages or certain manufacturing processes may be contributing to the elevated TFA concentrations, Gu said. However, we did not analyze individual ingredients or investigate the manufacturing processes, so we cannot definitively identify the sources of TFA in these products. That caveat is important. The study establishes a pattern and a hypothesis-generating signal, not a proven mechanism, and the team is explicit that pinpointing whether additives, processing aids, packaging interactions or some combination of factors is responsible will require follow-up work at the ingredient and process level.

TFA can enter the environment through multiple pathways, including the breakdown of certain fluorinated refrigerants, pesticides and other chemicals. Once formed, it can be transported through precipitation into surface water and drinking-water sources. Its persistence and high mobility also make it exceptionally challenging to remove through conventional water treatment. This combination of traits, chemical stability that earns PFAS compounds their forever-chemical nickname together with a molecular structure that resists capture by standard filtration media, means that TFA can accumulate and circulate in water systems with few natural or engineered sinks. Conventional PFAS treatment technologies, including granular activated carbon and ion-exchange resins, are generally less effective at capturing TFA than many longer-chain PFAS compounds, and specialized testing methods are needed to reliably measure these smaller contaminants in the first place.

Despite the ubiquity of the detections, the researchers are careful to frame what the findings do and do not imply about health. Detecting TFA does not necessarily establish an immediate health risk, and scientific understanding of the compound’s long-term effects in humans remains limited, even as some toxicological studies have raised concerns about potential developmental and reproductive effects. I think it is important for consumers to understand that detecting a chemical in drinking water or beverages does not necessarily mean there is an immediate health risk, Venkatesan said. The potential health implications depend on the concentration, frequency of exposure, and how much of the chemical is consumed over time. That dose-and-duration framing is standard toxicological reasoning, but it also underscores how little is known: without robust human-health data for TFA and without regulatory limits comparable to those emerging for PFOA and PFOS, both utilities and consumers are left interpreting detections without a clear benchmark.

The study’s authors also emphasize that their work represents an initial snapshot of contamination rather than a comprehensive assessment of New Jersey’s drinking-water systems. Additional sampling will be needed to determine how concentrations vary over time and to identify the sources responsible for geographic differences between counties. Expanding monitoring efforts, they argue, will be essential to understanding the extent of contamination and determining whether additional treatment measures are warranted. At NJIT, the Emerging Contaminants Research Laboratory is already investigating technologies designed to improve PFAS removal, including pretreatment methods that enhance the ability of activated carbon to capture difficult-to-remove PFAS. The team plans to expand monitoring beyond New Jersey, investigate potential sources of TFA and examine how concentrations vary across drinking-water supplies and treatment systems, with the ultimate goal of connecting improved detection to more effective and affordable technologies that utilities can deploy against emerging contaminants.

The study, titled Occurrence of Ultra-Short Chain PFASs in Bottled Beverages and New Jersey Tap Water, was authored by Siwei Gu, Santhoshi Chitthaluri, Ebenezer Etsiwah, Bishnu Pandey and Arjun K. Venkatesan, and was supported in part by a faculty start-up grant from NJIT. Its broader significance may extend well beyond the Garden State. If TFA is this widespread in one of the most closely monitored water systems in the country, a state that has been at the forefront of PFAS regulation, the same blind spot almost certainly exists elsewhere. The research suggests that as regulators and utilities race to remove the legacy PFAS compounds they can now measure, an entire generation of smaller, more mobile and more persistent relatives may be passing unnoticed through the very systems built to keep drinking water clean, and that the beverages consumers reach for as alternatives to tap water may, in some cases, contain far higher concentrations than the water they are meant to replace.

Subject of Research: Occurrence of ultra-short-chain PFAS, particularly trifluoroacetic acid, in New Jersey tap water and bottled beverages

Article Title: NJIT study finds overlooked 'forever chemicals' widespread in New Jersey tap water and bottled beverages

Article References: NJIT study finds overlooked 'forever chemicals' widespread in New Jersey tap water and bottled beverages. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: PFAS, trifluoroacetic acid, TFA, drinking water, bottled beverages, New Jersey, water treatment, emerging contaminants, environmental monitoring, NJIT, forever chemicals, water safety

The scale of the analysis is what sets it apart. The team compiled data for 65 different PFAS compounds, including all twenty substances covered by the European regulatory list, across 163 bottled water samples drawn from 34 brands purchased in France, Italy, Belgium, Romania, Portugal, Lithuania, Georgia, Morocco, the United States, Mexico, and China. That geographic breadth matters because bottled water is a global commodity, and most existing studies of PFAS in drinking water have focused on municipal tap supplies within single countries or regions. Data on bottled water specifically have remained surprisingly sparse, even though millions of consumers treat it as their primary source of drinking water and even though natural mineral waters are subject to a different, and in some respects less chemically prescriptive, European regulatory regime than tap water.

PFAS are a family of thousands of synthetic chemicals built around chains of carbon atoms bonded to fluorine, one of the strongest bonds in organic chemistry. That carbon-fluorine backbone is what makes them so useful in products ranging from nonstick cookware and water-repellent textiles to firefighting foams, and it is also what makes them extraordinarily persistent in the environment. Some members of the family are linked to cancer, liver damage, immune suppression, and endocrine disruption, and they accumulate in the human body over years of exposure. Drinking water is considered a major route of human exposure, which is why the European Union’s Drinking Water Directive, adopted in 2020, set a cumulative limit of 100 nanograms per liter for the sum of twenty specific PFAS compounds. The new study checked every sample against that benchmark and found that the sum of the twenty regulated compounds stayed below 56 nanograms per liter in all cases, comfortably within the legal limit.

That compliance result is genuinely good news for the bottled water industry and for consumers who rely on it. It suggests that the sources feeding commercial bottling operations, which are typically deep aquifers or protected springs rather than surface waters, have so far largely escaped the contamination that has plagued many municipal supplies downstream of industrial dischargers and firefighting training sites. It also suggests that the treatment and bottling processes themselves are not introducing the longer-chain, regulated PFAS in measurable amounts. For the twenty compounds that regulators in Europe have prioritized, the message of this study is that bottled water, at least the 34 brands examined here, is currently a minor exposure pathway.

But the study’s second message is where the scientific and regulatory interest really lies. Among all 65 compounds screened, the only PFAS actually detected was trifluoroacetic acid, a substance that does not appear on the European regulatory PFAS list at all. Trifluoroacetic acid, usually abbreviated TFA, is the smallest member of the perfluoroalkyl acid family, with just a single carbon atom in its chain. Its ultrashort structure gives it unusual behavior in water: it is extremely mobile, essentially non-degradable, poorly removed by conventional drinking water treatment including activated carbon filtration and reverse osmosis under typical operating conditions, and it is not retained by the natural attenuation processes that can slow longer-chain compounds. Environmental scientists have warned in recent years that TFA is accumulating irreversibly in the global water cycle, with atmospheric degradation of refrigerant gases and fluorinated pesticides identified as substantial diffuse sources alongside industrial emissions.

The concentrations the researchers measured reveal a striking geographic pattern. Trifluoroacetic acid was systematically found in bottled waters from France, Belgium, and Morocco, with mean concentrations of 461 plus or minus 322 nanograms per liter, 438 plus or minus 178 nanograms per liter, and 74 plus or minus 12 nanograms per liter respectively. In Italy, the compound appeared in two brands at 350 plus or minus 49 and 88 plus or minus 16 nanograms per liter, while everywhere else in the survey concentrations remained below 50 nanograms per liter. The French figures are particularly notable because the mean of 461 nanograms per liter, with considerable variability between brands, represents concentrations several times higher than the cumulative regulatory limit that applies to the twenty regulated PFAS, even though TFA itself is not covered by that limit. The wide standard deviation for France indicates that some individual brands carry substantially more TFA than others, pointing to differences in the vulnerability of the aquifers and springs from which the water is drawn.

Why does TFA dominate where the regulated compounds do not? The answer lies in the chemistry and in the sources. The longer-chain PFAS that regulators have prioritized tend to bind to soils and sediments, move slowly through aquifers, and originate from relatively localized industrial and firefighting sources. TFA, by contrast, is generated continuously and diffusely. Hydrofluorocarbon and hydrofluoroolefin refrigerants, introduced as replacements for ozone-depleting substances, break down in the atmosphere to yield TFA that then falls with rain and snow. Certain pesticides degrade to trifluoroacetate in soils and leach into groundwater. Because these sources are distributed across entire regions rather than concentrated at a few discharge points, even well-protected aquifers used for bottling can carry measurable TFA loads. Studies in China have documented a seventeenfold increase in TFA in landscape waters around Beijing over a single decade, and researchers in Germany have identified ultrashort-chain PFAS as prevalent, overlooked, difficult to remove, and unregulated contaminants in the sources of drinking water.

The health implications of the measured TFA levels remain an open scientific question, and the study’s authors are careful not to overstate them. TFA has historically been regarded as one of the less toxic members of the PFAS family, and there is no drinking water limit for it in most jurisdictions. Yet the lack of a limit reflects a gap in the regulatory framework rather than a demonstrated absence of risk. The compound’s extreme persistence means that whatever enters aquifers now will remain there indefinitely, and environmental concentrations are rising globally. Some recent assessments have called for a more precautionary approach precisely because exposure is universal, irreversible on human timescales, and growing. The finding that a bottled water product, which consumers often choose specifically to avoid perceived contaminants, can carry hundreds of nanograms per liter of an unregulated fluorinated acid underscores how far the regulatory net still falls short of the actual chemical landscape.

The authors conclude that their findings highlight the need to include trifluoroacetic acid in bottled water monitoring, and that recommendation carries practical weight. Monitoring programs built around the twenty-compound European list would have reported every sample in this study as essentially clean, since nothing regulated was quantifiable. Only the broader 65-compound screen revealed the TFA signal. As regulators in Europe and elsewhere consider how to handle ultrashort-chain PFAS, studies like this one provide exactly the kind of occurrence data needed to set meaningful thresholds. The work also demonstrates the value of international collaborative networks, with the research supported by partnerships among universities in Besançon, Bari, Bucharest, Xi’an, and Sinaloa under a multi-year project running through 2029.

For consumers, the practical takeaway is measured rather than alarming. The regulated PFAS burden in the bottled waters tested is low, and the TFA levels, while notable, come with no established health-based limit to breach. What the study changes is the frame of the conversation. It shows that the forever chemicals problem is not confined to industrial river basins and contaminated municipal supplies, but has reached even the protected underground sources of premium bottled water through the diffuse, atmospheric, and agricultural pathways of the smallest PFAS molecule. It also shows that regulatory lists, however carefully constructed, can create blind spots: a water can comply fully with the law while still carrying a fluorinated compound at concentrations an order of magnitude above the legal threshold for its regulated cousins. Closing that gap between what is regulated and what is actually in the bottle is, the authors argue, the next necessary step in protecting drinking water quality worldwide.

Subject of Research: Occurrence of per- and polyfluoroalkyl substances, including trifluoroacetic acid, in bottled water from 11 countries

Article Title: Per- and poly-fluoroalkyl substances in bottled water samples from France, Italy, Belgium, Romania, Portugal, Lithuania, Georgia, Morocco, United States, Mexico, and China

Article References: Crini, G., Angonin, L., Mongioví, C., Elaissaoui, Z., Picos-Corrales, L. A., Rousseau, J., Bradu, C., Lichtfouse, E., Ansell, G. K., Grzymsky, G., & Lacalamita, D. (2026). Per- and poly-fluoroalkyl substances in bottled water samples from France, Italy, Belgium, Romania, Portugal, Lithuania, Georgia, Morocco, United States, Mexico, and China. Environmental Chemistry Letters. https://doi.org/10.1007/s10311-026-01929-9

Image Credits: AI Generated

DOI: 10.1007/s10311-026-01929-9

Keywords: PFAS, trifluoroacetic acid, bottled water, drinking water, forever chemicals, ultrashort-chain PFAS, European Drinking Water Directive, water contamination, environmental chemistry, TFA, water quality monitoring, groundwater