--- topic: "BPS and BPF" title: "BPA-Free Is Not Safe" order: 1 description: "Why the chemicals replacing BPA in 'BPA-free' products carry the same endocrine-disrupting risks — and how to actually reduce your exposure" question: "Are BPA-free plastics made with BPS or BPF actually safer?" answer: "BPS and BPF may be as hormone-disrupting as BPA; lab and animal studies show similar activity, but human disease data are limited." actions: - "Decline paper receipts or ask for email ones, and wash your hands before eating after handling them." - "Store food in glass or stainless steel, and never heat food in plastic of any kind." - "Choose fresh or frozen produce over canned, and consider a carbon or reverse osmosis filter for tap water." cautions: - "'BPA-free' only means BPA was removed; BPS or BPF may have replaced it, with similar hormonal activity in lab studies [1]." - "Children tended to have higher BPS levels than adults in US survey data, so exposure reduction matters for kids [2]." confidence: 2 confidenceNote: "A systematic review of 32 mostly lab studies, three zebrafish or rat studies, and US exposure surveys; no human disease-outcome data." evidenceSummary: rctCount: 0 observationalCount: 1 metaAnalysisCount: 1 replicated: false newestStudyYear: 2022 references: - id: "1" pmid: "25775505" title: "Bisphenol S and F: A Systematic Review and Comparison of the Hormonal Activity of Bisphenol A Substitutes" authors: "Rochester JR, Bolden AL" year: 2015 journal: "Environmental Health Perspectives" - id: "2" pmid: "29978145" title: "Exposure to Bisphenol A, Bisphenol F, and Bisphenol S in U.S. Adults and Children: The National Health and Nutrition Examination Survey 2013-2014" authors: "Lehmler HJ, Liu B, Gadogbe M, Bao W" year: 2018 journal: "ACS Omega" - id: "3" pmid: "25583509" title: "Low-Dose Exposure to Bisphenol A and Replacement Bisphenol S Induces Precocious Hypothalamic Neurogenesis in Embryonic Zebrafish" authors: "Kinch CD, Ibhazehiebo K, Jeong JH, Habibi HR, Kurrasch DM" year: 2015 journal: "Proceedings of the National Academy of Sciences" - id: "4" pmid: "25723814" title: "Rapid Responses and Mechanism of Action for Low-Dose Bisphenol S on Ex Vivo Rat Hearts and Isolated Myocytes: Evidence of Female-Specific Proarrhythmic Effects" authors: "Gao X, Ma J, Chen Y, Wang HS" year: 2015 journal: "Environmental Health Perspectives" - id: "5" pmid: "29016128" title: "Acute Toxicity, Teratogenic, and Estrogenic Effects of Bisphenol A and Its Alternative Replacements Bisphenol S, Bisphenol F, and Bisphenol AF in Zebrafish Embryo-Larvae" authors: "Moreman J, Lee O, Trznadel M, David A, Kudoh T, Tyler CR" year: 2017 journal: "Environmental Science and Technology" - id: "6" pmid: "35297356" title: "BPS and BPF are as Carcinogenic as BPA and are Not Viable Alternatives for Its Replacement" authors: "Edaes FS, de Souza CB" year: 2022 journal: "Endocrine, Metabolic and Immune Disorders - Drug Targets" --- When products are labeled "BPA-free," it means one thing: bisphenol A has been removed. What it does not mean is that the replacement chemicals are safe. Most BPA-free plastics and thermal receipt papers now contain bisphenol S (BPS) or bisphenol F (BPF) — close chemical relatives that research shows are similarly disruptive to the endocrine system [1]. Both have now been detected in the urine of more than 89% of Americans [2], meaning near-universal exposure to compounds we've barely begun to study. ## What BPS and BPF Are BPS (bisphenol S) and BPF (bisphenol F) belong to the same family of industrial chemicals as BPA — all built around two phenol rings joined by a central carbon. This shared structure is what gives them all estrogenic properties: the molecule fits into estrogen receptors in the human body, triggering hormonal signals at vanishingly small concentrations. When public and regulatory pressure forced the phaseout of BPA in water bottles, food containers, and baby products, manufacturers quietly swapped in BPS and BPF. Because these compounds had not been studied extensively, they could be labeled "BPA-free" without scrutiny. The regrettable irony is that the structural similarity that makes them functional replacements is the same similarity that makes them biologically active in the same ways. **Where you encounter them:** - Thermal receipt paper (the main route of skin absorption for BPS) - BPA-free plastic bottles, containers, and food storage bags - The linings of canned foods - Some dental sealants - Paper currency and boarding passes (often treated with BPS) BPS is now so common in thermal paper that it is estimated to account for more than 90% of the thermal paper market globally. ## Hormonal Disruption: How Similar Is the Risk? A 2015 systematic review in Environmental Health Perspectives, one of the most comprehensive assessments published, analyzed 32 studies and concluded that BPS and BPF are "as hormonally active as BPA" across multiple hormone pathways — estrogenic, antiestrogenic, androgenic, and antiandrogenic [1]. This was not a marginal finding; the activity was of similar magnitude. In cell studies, BPS has been shown to activate membrane estrogen receptors at femtomolar concentrations — that is, at one-quadrillionth of a gram per liter of fluid [1]. At these concentrations, the compounds interfere with how cells respond to the body's own estrogen, producing effects on cell proliferation and signaling. ## Neurological Development Concerns A 2015 study published in the Proceedings of the National Academy of Sciences used zebrafish embryos — a standard model for early developmental biology — to compare BPA and BPS side by side [3]. Both compounds caused a 240% increase in hypothalamic neuron birth rate in developing embryos. The hypothalamus regulates appetite, stress response, temperature, sleep, and reproduction. Abnormal neuronal proliferation during critical developmental windows is linked to lasting behavioral and cognitive changes. The researchers explicitly noted that their findings challenged the assumption underlying the "BPA-free" marketing claim: that switching to structural analogs resolves the biological hazard. ## Cardiovascular Effects Research published in Environmental Health Perspectives found that low-dose BPS exposure produced proarrhythmic effects in isolated rat hearts — specifically increasing the frequency of ventricular arrhythmia events under stress conditions, with effects that were more pronounced in female cardiac tissue [4]. This mirrors concerns previously raised about BPA's cardiovascular effects and suggests the replacement chemicals carry a similar cardiac risk profile. ## BPF and Developmental Toxicity BPF has been found to be estrogenically equivalent to BPA in zebrafish embryo studies, with both compounds producing developmental deformities — including cardiac edema, spinal malformation, and craniofacial abnormalities — though only at concentrations between 1.0 and 200 mg/L, which exceed those in most environments [5]. A 2022 review concluded that neither BPS nor BPF represent a viable safe replacement for BPA from a carcinogenicity standpoint [6]. ## How to Reduce Exposure The goal is to reduce bisphenol contact in general, since current evidence gives no reason to treat BPA-free products as safer: - **Decline receipts** when you do not need them, or request email receipts. Receipt paper is the largest single-source contributor to BPS skin exposure. After handling receipts, wash hands before eating. - **Use glass or stainless steel** for food and beverage storage rather than plastic containers of any kind. - **Avoid canned foods** where possible, or choose brands using BPA/BPS-free linings made from acrylic or oleoresin alternatives. Tetrapak cartons are generally a lower-bisphenol option. - **Never heat food in plastic** — heat dramatically accelerates leaching of bisphenols into food regardless of which variant is used. - **Filter your water** using a high-quality carbon or reverse osmosis filter. BPS has been detected in tap water in multiple countries. - **Choose fresh or frozen over canned** for produce. See our [BPA page](/bpa) for more on the original bisphenol, and our [PFAS page](/pfas) for another category of pervasive plastics-related toxins. ## Evidence Review **Hormonal activity equivalence — Rochester & Bolden (2015)** The Rochester and Bolden systematic review [1] is the defining reference for this topic. Searching literature through 2014, the authors identified 32 in vitro and in vivo studies evaluating the hormonal activity of BPS and BPF. Their analysis found that both compounds demonstrate estrogenic activity broadly comparable to BPA, with activity detected across estrogen receptor alpha, estrogen receptor beta, and membrane estrogen receptor pathways. They also found antiestrogenic, androgenic, and antiandrogenic activity, indicating broad endocrine disruption rather than a narrow estrogenic effect. The authors concluded there is "no evidence that BPS and BPF are safer alternatives to BPA." A key limitation is that most studies available at the time of review were in vitro; the authors noted the urgent need for more in vivo and epidemiological data. **Population exposure — Lehmler et al. (2018)** Using NHANES 2013–2014 urinary data from a nationally representative sample of U.S. children and adults, Lehmler et al. [2] found BPS detectable in 89.4% of samples and BPF in 66.5%. Median urinary BPS concentration was 0.18 µg/L; the 95th percentile reached 3.4 µg/L. These detection rates are comparable to BPA's ubiquity at the height of its use. The data confirm that regulatory action on BPA has not meaningfully reduced total bisphenol body burden — it has only shifted which bisphenol is present. Children tended to have higher BPS levels than adults, consistent with greater hand-to-mouth behavior and proximity to treated surfaces. **Neurodevelopmental effects — Kinch et al. (2015)** Kinch and colleagues [3] exposed zebrafish embryos to BPA and BPS at concentrations ranging from 0.0068 µg/L to 68 µg/L during the first 24 hours of development. Both compounds produced a 240% increase in hypothalamic neuron production at concentrations as low as 0.0068 µg/L — a concentration within the range of detected environmental levels. The mechanism involved estrogen receptor signaling: blocking estrogen receptors abolished the effect. This is significant because it shows that BPS is not merely weakly estrogenic at high doses but is biologically active at concentrations that overlap with real-world exposure, and at the earliest stages of neural development. The authors acknowledged that zebrafish models have limitations in predicting human outcomes, but noted the conservation of estrogen receptor pathways across vertebrates makes the finding relevant. **Cardiac effects — Gao et al. (2015)** Working with ex vivo rat heart preparations and isolated ventricular myocytes, Gao and colleagues [4] applied BPS at concentrations of 1 nM and 1 µM — representing low and moderate environmental/occupational exposures respectively. BPS induced rapid, non-genomic responses in cardiac tissue: at 1 nM, it increased the frequency of spontaneous calcium release events (sparks) — a marker of arrhythmia susceptibility — by approximately 60% in female myocytes. In intact heart preparations under isoproterenol stress (simulating sympathetic activation), BPS-treated female hearts showed a marked increase in ventricular arrhythmia. Effects were sex-specific, with female tissue consistently more sensitive, a pattern also seen with BPA. The researchers proposed that BPS activates estrogen receptor-mediated signaling in cardiac cells through a non-transcriptional pathway, directly altering ion channel behavior. **Developmental toxicity of BPF — Moreman et al. (2017)** This study [5] compared BPA, BPS, BPF, and BPAF in zebrafish embryo-larvae, assessing acute toxicity, teratogenic effects, and estrogenic activity in an estrogen-responsive transgenic fish. BPF was found to be as estrogenic as BPA (estrogenicity ranking: BPAF > BPA = BPF > BPS; toxicity ranking: BPAF > BPA > BPF > BPS). Developmental deformities — cardiac edema, spinal malformation, and craniofacial deformities — differed in effect and potency between the bisphenols and occurred only at concentrations between 1.0 and 200 mg/L, which exceed those in most environments. The study is valuable for directly comparing the four analogs head-to-head in the same experimental model; the authors concluded that these BPA alternatives induce similar toxic and estrogenic effects to BPA and that BPAF is more potent than BPA. **Carcinogenicity assessment — Edaes & de Souza (2022)** This narrative review [6] examined the oncogenic potential of BPS and BPF relative to BPA, focusing on mechanisms including estrogen-receptor-mediated cell proliferation, oxidative stress induction, and epigenetic modification. The authors concluded that the weight of evidence does not support treating BPS or BPF as safer replacements from a carcinogenicity standpoint. They called for regulatory frameworks that assess bisphenol analogs as a class rather than evaluating each in isolation after it has already achieved widespread use — a regulatory pattern that has allowed BPS and BPF to repeat BPA's trajectory of widespread deployment before adequate safety evaluation. **Overall evidence assessment** The evidence base for BPS and BPF health risks is growing but still substantially smaller than the literature on BPA. Most mechanistic studies use in vitro cell models or zebrafish embryos; robust human epidemiological data directly linking BPS or BPF exposure to disease outcomes are limited. However, the structural similarity to BPA, the consistent findings of estrogenic activity across independent laboratories, the near-universal population exposure confirmed by NHANES, and the multiple pathways of effect (endocrine, neurological, cardiac) together constitute a credible precautionary concern. The history of BPA — approved and widely used for decades before evidence of harm accumulated — provides a strong argument for applying the precautionary principle to its structural analogs rather than waiting for definitive human disease data to emerge.