Marcelis 2024 - feminine intimate products safety thesis

Marcelis’s PhD thesis develops a safety-assessment workflow for feminine intimate products, combining extractables/leachables testing, menstrual/vaginal fluid simulants, fragrance-allergen QRA, and in vitro mixture testing. Chapter 2 contains the same chemical-characterization program later published as Marcelis et al. 2025, so its metal leachables should be treated as overlapping provenance rather than an independent occurrence replicate. The thesis is C-tier thesis evidence; the later peer-reviewed Environment International article remains the preferred primary occurrence anchor for the Chapter 2 metal table.

Key numbers

The thesis market survey purchased 64 feminine intimate products: tampons (n=9), sanitary napkins (n=6), adult novelties (n=15), menstrual cups (n=15), Kegel-exercise devices (n=14), and menstrual sea sponges (n=5). Product origin/source criteria included EU, US, and Asia; the thesis discussion later describes the sample as including the European Union, United States, and China.

Chapter 2 reports an inorganic leachables pilot using 5 samples from each of four product categories: adult novelties, Kegel-exercise devices, menstrual sea sponges, and menstrual cups. Tampons and sanitary napkins are part of the broader 64-product chemical-characterization study, but they are not quantified in Table 2-10’s inorganic leachables grid. Table 2-10 expresses leachate values in ng/mL.

Category-level maxima from Table 2-10 were:

For menstrual sea sponges, Table 2-10 also reports maximum Li 2.6 ng/mL, Mn 117.2 ng/mL, Fe 4930 ng/mL, Co 28.0 ng/mL, Cu 22.4 ng/mL, Zn 95.9 ng/mL, Se 7.1 ng/mL, and Ba 9.8 ng/mL. Adult novelties had maximum Li 15.1 ng/mL, Mn 1.1 ng/mL, Cu 1.9 ng/mL, Zn 122.7 ng/mL, and Ba 3.2 ng/mL. Menstrual cups had maximum Mn 1.1 ng/mL, Co 3.5 ng/mL, Cu 6.1 ng/mL, and Ba 14.9 ng/mL; Kegel-exercise devices had maximum Ba 2.4 ng/mL.

The thesis narrative highlights menstrual sea sponges as having the highest metal(loid) leaching among the tested product categories. It reports maximal sea-sponge values for aluminum 1661.8 ng/mL, chromium 28.9 ng/mL, manganese 117.2 ng/mL, iron 4930 ng/mL, cobalt 28 ng/mL, nickel 1850.2 ng/mL, copper 22.4 ng/mL, arsenic 28.6 ng/mL, selenium 7.1 ng/mL, cadmium 1ng/mL, antimony 0.3ng/mL, and mercury 0.6ng/mL; the source’s spacing around 1ng/mL and 0.3ng/mL is preserved in this note.

Table 2-9 reports 19 organic chemicals leaching from the 64 products under simulated-use conditions. Maximum organic leachable values included heliotropine 1.79 µg/mL, triethyl citrate 18 µg/mL, di-n-octyl phthalate 100 ng/mL, diethyl phthalate 70 ng/mL, bis(2-ethylhexyl) phthalate 25 ng/mL, dibutyl phthalate 22 ng/mL, cyclohexanone 0.23 µg/mL, benzophenone 0.19 µg/mL, and menthyl salicylate 0.90 µg/mL. Benzyl butyl phthalate had positive tampon, sanitary-pad, and panty-liner samples, but the maximum is reported as < LLOQ.

Chapter 3 uses the Chapter 2 leachables data for a fragrance-allergen QRA in 8 scented menstrual hygiene products from the Belgian market: 5 tampons, 2 sanitary pads, and 1 panty liner. The thesis states that the detected fragrance substances were not disclosed on product labels. Table 3-6 reports consumer exposure levels in µg/cm²/day for an exposure scenario of 6 products per day, each used for 4 hours; the highest reported CEL was heliotropine in tampon T5 at 5.25 µg/cm²/day. Table 3-7 reports AEL/CEL ratios from 0.94 for heliotropine in tampon T5 to 7637.48 for geraniol in panty liner TS1.

Methods (brief)

The thesis adapts ISO 10993 extractables/leachables concepts for feminine intimate products. Exaggerated extractables testing used cut product pieces, headspace GC-MS, GC-MS, and LC-HRMS. Simulated-use leachables testing used menstrual fluid simulant (MFS) and vaginal fluid simulant (VFS) at 37°C; menstrual cups used 25 mL MFS, while adult novelties and Kegel-exercise devices leached into 50 mL VFS. The inorganic pilot measured Li, Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, As (O2), Se, Cd, Sb, Ba, Pb, Sn, and Hg by ICP-MS with H2 reaction gas, a 0.005-10 ppb calibration range, NIST1568b certified reference material, procedural blanks, reagent blanks, and drift checks every 20 samples.

Implications

Certification: The thesis is useful as methodological and provenance context for menstrual/intimate product leachables. For metals, Chapter 2 overlaps the later Marcelis et al. 2025 peer-reviewed source and should not be pooled as a second independent occurrence dataset.

Courses: This is a strong teaching source for the difference between extractables and leachables, and for why simulated-use conditions, fluid composition, and contact time must be preserved before comparing menstrual-product measurements.

App: The source can support evidence-card context about leachables testing and fragrance-allergen QRA in menstrual hygiene products, with category-level wording only. Product and brand identities should remain suppressed.

Microbiome: The thesis discusses the vulvovaginal environment and uses menstrual/vaginal fluid simulants, but it does not measure a vaginal microbiome endpoint.

Wiki pages this source may touch

• menstrual-tampons
• menstrual-pads
• menstrual-cups
• menstrual-intimate-products-other
• aluminum
• chromium
• nickel
• arsenic-total
• cadmium
• antimony
• lead
• tin
• mercury-total

Verification notes

Identity checks before drafting found no existing wiki/sources/ hit for raw handle MFK_paper-30-marcelis-2024-phd-thesis, cite key marcelis2024-feminine-intimate-products-thesis, the exact thesis title, or PDF SHA-256 3eba9b78017ef85de9967025ef4f28cd4d308ff755947593d10f5571d51bd093. The thesis has no DOI printed in the extracted text; doi: null and no_doi_assigned: true are retained. The front matter lists license: "CC BY" because the VUB cover page prints License: CC BY.

Tables 2-9, 2-10, 3-3, 3-5, 3-6, and 3-7 were re-opened from /tmp/hmi-fem-021.txt. Table 2-10 values are copied as ng/mL leachate values without conversion, even though the later peer-reviewed article page records the same table on its own ppb wording. The As (O2) table header is treated as total arsenic measured in ICP-MS oxygen/reaction mode, not inorganic arsenic speciation; no Cr-VI, methylmercury, organotin, or elemental tin speciation is reported. Brand firewall: the thesis describes popular brands and low-budget options, but this page reports only product-category and sample-code summaries. Product, matrix, metal, and jurisdiction slugs were checked against the closed taxonomy snapshot. The closed ingredient vocabulary has no valid material slug for this thesis’s consumer-product/device materials, so ingredients: [] is intentionally retained. The near-duplicate link to marcelis2025-micp-leachables-metals is recorded because Chapter 2 lists the chemical-characterization article as in preparation and contains the same inorganic leachables table.

Page history

The five most recent substantive edits to this page. The full version history lives in git; when DOI minting comes online (see schema docs), each entry below will also link to a version-pinned DataCite DOI.