New evidence links chemical UV filters to altered pubertal timing in children
- Dr Yousuf Mohammed
- Jul 9
- 3 min read
Updated: Aug 31
A peer‑reviewed study published in Chemosphere (2023) reports that combined exposure to organic UV filters—the chemical actives found in many conventional sunscreens—and phthalates—plasticisers used in packaging and personal‑care products—can alter pubertal development in a gender‑specific way.¹
Why this paper matters to Australia
Oxybenzone (BP‑3)—one of the UV filters highlighted—remains an allowed active in Australian therapeutic sunscreens up to 10 % (though the TGA has just proposed cutting that limit to 1 %).
Children are routinely exposed to both chemical UV filters and phthalates through sunscreen use, cosmetics, food packaging and microplastics.
The study adds to a growing body of literature suggesting endocrine‑disrupting effects of chemical filters—precisely the concern now driving the TGA to tighten national standards (see our July 2025 briefing on the proposed Schedule 5 listings).
Study at a glance
Core findings
Boys
Higher urinary levels of BP‑3 (oxybenzone) and 4′‑MAP were negatively associated with genital development (OR ≈ 0.5) and pubic‑hair stage (OR ≈ 0.24).
Mixed exposure (phthalate + UV‑filter mixture) corresponded to a 70 % reduction in genital‑stage progression—larger than any single chemical effect.
Girls
Elevated MEP (a phthalate metabolite) was linked to earlier breast development (OR ≈ 1.3–1.6).
Chemical mixtures were associated with a more than 2.5‑fold increase in odds of earlier puberty onset.
Interpretation: Chemical UV filters and phthalates appear to delay puberty in boys but accelerate puberty in girls, with mixtures exerting a stronger effect than individual compounds—suggesting synergistic endocrine disruption.
Limitations to keep in mind
Sample size is modest (n = 223).
Single‑region cohort may limit generalisability.
Urinary biomarkers capture recent exposure; they do not pinpoint long‑term body burden.
Diet, genetics and other environmental factors were not fully controlled.
Despite these caveats, the study employs advanced mixture‑modelling (qgcomp) now recognised as best practice for examining real‑world exposures.
Implications for policy and practice
Regulatory relevance – The findings support the TGA’s July 2025 proposal to restrict oxybenzone to 1 % and to list homosalate and benzophenone in Schedule 5. Mixture effects warrant even broader reviews—for example, on 4‑MBC and octocrylene, which were not measured here but share similar mechanisms.
Product reformulation – Sunscreen manufacturers should accelerate the shift toward mineral actives (non‑nano zinc oxide or titanium dioxide) with inert solvents, eliminating phthalate‑containing packaging where feasible.
Research gaps – Longitudinal, Australian‑based cohorts are urgently needed to characterise exposure pathways and endocrine outcomes in local children.
ASC position
The Australian Sunscreen Council advocates a precautionary approach:
Support science‑based limits on endocrine‑active chemical filters and plasticisers.
Encourage mineral‑only sunscreens that meet high SPF/UVA standards without petro‑chemical boosters such as butyloctyl salicylate (BOS).
Promote transparent labelling so parents can make informed choices.
For parents and carers seeking immediate options, see our curated list of zinc‑only sunscreens available nationally, all free of chemical boosters and phthalates (ASC blog, 8 July 2025).
Reference
Zhou Y, Wang P, Li J, et al. (2023). Mixed exposure to phthalates and organic UV filters affects children's pubertal development in a gender‑specific manner. Chemosphere, 338, 138073. https://doi.org/10.1016/j.chemosphere.2023.138073
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