New Research Links Sunscreen Chemical 4-MBC With Higher Blood Glucose in Healthy Adults
- Australian Sunscreen Council
- 1 day ago
- 7 min read
Australian Sunscreen Council calls for urgent TGA action to halt sales of 4-MBC sunscreens, particularly products marketed to children
A new peer-reviewed study published in Scientific Reports, part of the Nature Portfolio, has identified the sunscreen UV filter 4-Methylbenzylidene Camphor, commonly known as 4-MBC, as one of several environmental pollutants associated with higher fasting blood glucose in otherwise healthy adults.
The study, titled Environmental pollutants associated with blood glucose levels in healthy individuals, examined serum samples from 307 individuals in northern China using liquid chromatography-tandem mass spectrometry. Researchers screened 203 environmental exposure substances across 11 major categories, including ultraviolet stabilisers, endocrine disruptors, persistent organic pollutants, PFAS, phthalates, pesticides and personal care product chemicals.
The study’s key finding for sunscreen regulation is clear: 4-MBC was positively associated with increased blood glucose levels, even after adjustment for common confounding factors.
In the paper’s own words, “4-MBC… showed a significant positive correlation” with blood glucose elevation. The authors also concluded that “Environmental pollutants are important risk factors” for increased blood glucose in healthy individuals.
The Australian Sunscreen Council is calling for urgent action by the Therapeutic Goods Administration to halt the sale of sunscreens containing 4-MBC, particularly products marketed to children, while the regulator conducts a transparent safety review.
Consumers asking whether a sunscreen containing 4-MBC is suitable for their children should be told plainly: the TGA’s January decision stated that no safe dose could be established for 4-MBC in sunscreens.
Why this matters
4-MBC is not an obscure industrial contaminant. It is a chemical UV filter used in several Australian sunscreen marketed towards children. It has already been the subject of serious international concern because of its endocrine-disrupting properties, including effects on estrogen and thyroid systems.
The Australian Sunscreen Council has previously reported that 4-MBC is prohibited, restricted or not approved across 109 jurisdictions, including the European Union, United Kingdom, United States, China and Japan. See: The Global Consensus: A Worldwide Rejection of 4-MBC by 78 Nations.
That article also notes that the European Union removed 4-MBC from the permitted UV-filter list and added it to the prohibited substances list, while the United Kingdom’s safety process concluded that “no safe use level could be established” for the UV filter 4-MBC.
This new Scientific Reports study adds another reason for concern: possible metabolic effects.
The study did not focus on people already diagnosed with diabetes. It examined people at an earlier stage, where blood glucose is still within or near the normal range and where early prevention may matter most.
The authors explain that diabetes develops gradually and that environmental exposures during the pre-diabetic stage remain poorly understood. They state that environmental exposure research in non-diabetic populations has been “largely been neglected”.
What the study found about 4-MBC
The researchers divided participants into two groups based on fasting plasma glucose:
normal glucose: FPG below 5.6 mmol/L
higher glucose: FPG at or above 5.6 mmol/L
After analysing 203 exposure substances, the study found that 4-MBC, α-HBCD and benzil were elevated in the higher-glucose group.
The paper reports that 4-MBC, benzil and α-HBCD showed “higher expression in the higher glucose group”.
In the multivariate logistic regression analysis, which adjusted for gender, age, BMI, blood pressure and lipid markers, 4-MBC remained associated with increased risk of higher blood glucose.
For 4-MBC, the reported odds ratio was:
OR = 1.141; 95% CI: 1.034–1.260; P = 0.009
That means the association remained statistically significant after adjustment for major measured confounders.
The study also used Weighted Quantile Sum and Bayesian Kernel Machine Regression models to assess the combined effect of multiple exposures. The authors reported that for every one interquartile range increase in the exposure-mixture score, the risk of blood glucose elevation increased:
OR = 1.401; 95% CI: 1.141–1.721; P < 0.001
The paper states this showed “a significant positive correlation” between overall exposure increase and blood glucose elevation.
Importantly, 4-MBC was one of the highest-weight contributors in the WQS mixture model, second only to α-HBCD.
What the authors said about 4-MBC
The discussion section states that “4-MBC… has been proven to possess remarkable endocrine-disrupting properties.”
The authors also note that studies have shown 4-MBC can interfere with sex-hormone systems and thyroid function, and that long-term exposure may have broader health consequences.
The Australian Sunscreen Council believes this finding should be considered alongside previous international assessments that have raised concerns about 4-MBC’s endocrine activity, unresolved safety profile and lack of an established safe dose for sunscreen use.
Why elevated blood glucose is a serious public health signal
This study cannot be used to definitively link 4-MBC to diabetes. However, it does identify 4-MBC as statistically associated with higher fasting blood glucose in healthy adults — a finding that is directly relevant to regulators because elevated blood glucose is a recognised marker of metabolic risk.
The United States Centers for Disease Control and Prevention, America’s national public-health agency, states: “Over time, high blood sugar can damage blood vessels and the nerves that control your heart.”
The National Institute of Diabetes and Digestive and Kidney Diseases, part of the US National Institutes of Health and one of the world’s leading government medical-research bodies, states: “High blood glucose from diabetes can damage your blood vessels and the nerves that control your heart and blood vessels.”
Diabetes Australia, the national body supporting Australians living with diabetes, states: “In the long term, persistent high blood glucose levels causes damage to blood vessels leading to complications that affect the nerves, eyes, kidneys and heart.”
The Australian Institute of Health and Welfare, the Australian Government’s national health and welfare statistics agency, reports that diabetes increases the risk of complications including heart disease, stroke, kidney disease, blindness and lower limb amputation.
Better Health Channel Victoria, a Victorian Government health-information service, explains that high blood glucose can damage large and small blood vessels, leading to heart attack, stroke and problems with the kidneys, eyes, feet and nerves.
The Heart Foundation, Australia’s leading heart-health charity, states that high blood sugar levels from diabetes can damage blood vessels in the heart, making them more likely to develop fatty deposits.
These national institutions are not commenting on 4-MBC specifically. Their relevance is that they explain why any credible research linking a consumer chemical exposure with higher blood glucose should be taken seriously by public-health regulators.
This is not about avoiding sunscreen. It is about avoiding unnecessary chemical risk
Australians need effective sun protection. The Australian Sunscreen Council strongly supports sun-safety measures, including shade, protective clothing, hats, sunglasses, avoiding peak UV where practical and using appropriate sunscreen when needed.
But sunscreen regulation should not require Australians to accept avoidable chemical exposure when safer and effective alternatives exist.
4-MBC is not needed to make an effective sunscreen. Australia permits multiple UV filters, among them Zinc Oxide which is the only broad-spectrum UV filter the US FDA considers Safe and Effective for use in sunscreens.
Where a chemical UV filter has been associated with endocrine disruption, is prohibited or not approved across major overseas markets, has no established safe dose according to the TGA’s January decision, and now appears in new peer-reviewed research as a blood-glucose risk factor, the burden should be on regulators and sponsors to demonstrate safety — not on parents to prove harm after years of exposure.
Why children’s sunscreens require immediate action
Products marketed to children carry a higher public-trust burden.
Parents reasonably assume that when a sunscreen is labelled, sold or promoted for children, it has been assessed against the highest available safety standards. They do not expect to find a chemical UV filter that major overseas regulators have rejected, restricted or prohibited.
The Australian Sunscreen Council believes consumers asking whether a sunscreen containing 4-MBC is “good for kids” should be clearly informed that:
4-MBC has been banned, restricted or not approved across major overseas markets;
the TGA’s January decision stated that no safe dose could be established for 4-MBC in sunscreens;
peer-reviewed research has now identified 4-MBC as positively associated with higher blood glucose in healthy adults;
safer and effective sunscreen alternatives are available.
Australian children should not be used as the test case for a sunscreen chemical already under international regulatory scrutiny.
What the Australian Sunscreen Council is calling for
The Australian Sunscreen Council calls for:
The TGA to urgently halt the sale of sunscreens containing 4-MBC, particularly products marketed for use on children.
The TGA to publish a transparent explanation of why 4-MBC remains permitted in Australian listed sunscreen products despite the January decision that no safe dose could be established.
Sponsors of 4-MBC sunscreens to disclose what current safety evidence they hold for daily use, paediatric use and use by pregnant women.
Retailers to immediately review children’s sunscreen ranges and remove 4-MBC-containing products from shelves.
Public-health messaging to prioritise shade, clothing, hats and physical sun protection before unnecessary daily chemical exposure.
A precautionary transition away from UV filters with unresolved endocrine, reproductive or metabolic safety concerns.
Study limitations
This study was cross-sectional, so it cannot prove causation. It involved 307 participants from northern China, and the authors acknowledge that larger population studies are needed.
However, the study remains important because it used modern high-throughput exposure analysis, measured chemicals in human serum, adjusted for multiple confounders and identified 4-MBC as a statistically significant blood-glucose risk factor.
For a sunscreen chemical already under international scrutiny, that should be enough to prompt serious regulatory action.
About the paper’s authors
The paper was authored by:
Xuekui Liu — Department of Endocrinology, Xuzhou Central Hospital, Southeast University Affiliated Xuzhou Central Hospital, Xuzhou, Jiangsu, China
Gangshan Peng — Department of Endocrinology, Xuzhou Central Hospital, Southeast University Affiliated Xuzhou Central Hospital, Xuzhou, Jiangsu, China
Yanhong Lin — Xuzhou Medical University, Xuzhou Clinical College, Xuzhou, Jiangsu, China
Wenruo Chen — Xuzhou Medical University, Xuzhou Clinical College, Xuzhou, Jiangsu, China
Houfa Geng — Department of Endocrinology, Xuzhou Central Hospital, Southeast University Affiliated Xuzhou Central Hospital, corresponding author
Jun Liang — Xuzhou Medical University, Xuzhou Clinical College, corresponding author
The study was approved by the Ethics Committee of Xuzhou Central Hospital. The authors declared no competing interests.
About the Australian Sunscreen Council
The Australian Sunscreen Council is Australia’s peak body for sunscreen safety, UV protection and ingredient transparency. Unlike broad industry associations representing cosmetics, personal care and hygiene sectors, ASC is focused specifically on sunscreen regulation, UV protection, sunscreen ingredient safety and public trust.
The Australian Sunscreen Council supports effective sun protection, including shade, protective clothing, hats, sunglasses and appropriate sunscreen use. It also advocates for a precautionary approach to sunscreen ingredients where credible scientific or regulatory concerns exist, particularly for products used on children, pregnant women and the general public on a daily basis.
References
Liu, X., Peng, G., Lin, Y., Chen, W., Geng, H. & Liang, J. Environmental pollutants associated with blood glucose levels in healthy individuals. Scientific Reports 16, 5592 (2026).
Australian Sunscreen Council. The Global Consensus: A Worldwide Rejection of 4-MBC by 78 Nations.
Centers for Disease Control and Prevention. Diabetes and Your Heart.
National Institute of Diabetes and Digestive and Kidney Diseases. Diabetes, Heart Disease, & Stroke.
Diabetes Australia. Hyperglycaemia — symptoms, risks and management.
Australian Institute of Health and Welfare. Diabetes: Australian facts — What is diabetes?.
Better Health Channel Victoria. Diabetes — long-term effects.
Heart Foundation. Diabetes and heart disease.
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