(320‒400 nm) radiation; a distinction between SPF and UVA protection factor (UVA-PF) is made. Many of the studies of

Overview

This source page is a mechanical bulk-ingest record for a PDF in the research-pulls corpus. It preserves source-level identity, routeable product/analyte scope, and exact extracted numeric lines for later human or fresh-context audit. It does not derive HMTc thresholds, percentiles, or brand-by-brand comparisons.

Key numbers

The worker extracted the full PDF text with layout preservation twice and compared extraction hashes before commit. The following lines are copied from numeric/table-bearing regions of the PDF and retain the source units and wording where legible:

titanium dioxide (TiO2) and zinc oxide (ZnO) and the mostly photo-unstable chemical UVB/UVA filters (e.g., octinoxate
Medicare beneficiaries increased dramatically, nearly 77%
by about 16% in the period 2002–2006. In the last year of Fig. 1 UVA, UVB and UVC components of the electromagnetic
the survey (2006), the total number of reported NMSCs was spectrum between the visible range and the gamma radiation; also
As a constituent of the electromagnetic spectrum, the and 5–10% UVB radiation (Fig. 2). Solar UV radiation pen-
length range 280–320 nm; the UVA light is the least ener- generates reactive oxygen species (ROS) that can damage
Table 1 Skin photo-type, skin responses on exposure to UVB/UVA radiation, minimal erythema dose (MED) and a measure of cancer risk
which is subdivided into six photo-types (Table 1), all of
UV radiation and thus to greater UV-induced mutations that Table 2 Sunscreen active ingredients included in the “stayed” 1999
radiation (Table 2) (10)—see sub-Sect. 3.2 for a description
available FDA’s approved sunscreen active agents (Table 2)
Table 2 (continued) that TiO2 has been used as a sunscreen active agent since
sunscreen formulations that contained 3% avobenzone
1.1 Physical UVB/UVA filters: category I contained 5% TiO2. Sunscreen products of similar SPF
radicals (HO2•) and singlet oxygen (1O2), responsible for ca. 17% in 2007 to about 41% in 2018 (24).
these nanoparticles. The risk of these metal oxides to the also showed that human skin absorbed about 0.34% of ZnO
were used at its maximum eligible concentration of 25% screen ZnO, a consequence of which was the accumulation
(Table 2), irrespective of the formulation of the sunscreen of free or labile Zn2+ that caused the cytotoxic effects and
the data on the physical properties of ZnO, concluded that at various Ce/Zn ratios (2.5 at%, 5 at%, and 10 at%). The
tion of a dye (crystal violet) by nearly 97% within a 30 min
Under dark conditions, titanium dioxide is an innocuous/ with sunlight alone for 0, 20, 40 and 60 min (lanes 1–4) and with 1%
anatase (lanes 5–8) or 1% rutile (lanes 9–12) TiO2 for the same times.
dental pastes, oral capsules, suspensions, tablets, dermal 10, 20, 40 and 60 min. The results are typical of those found with
preparations and non-parenteral medicines; in addition, its various samples. Bottom panel: illumination with 0.2% ZnO for 0,
ing DMSO; and with 0.0125% sunscreen TiO2 for 0, 5, 10, 20, 40
than ∼ 90% (30 min). By contrast, the R22B sample com-
the modified R22A specimen was ca. 80% after the 30-min
mate-O (Table 2) on DNA plasmids. The survival rate of
nium dioxide specimens (Note B means before modification, and UVA filter avobenzone (Fig. 10) and the UVB padimate-O
A means after modification). Irradiation times were 0, 10, 20 and sunscreen agent (Fig. 10e) were highly toxic to yeast cells
illumination, while only 15% of the supercoiled plasmids nated TiO2 on whole human skin cells in vitro (48). Several
of UVB radiation. avobenzone (Parsol 1789) was more unstable/toxic than the
histopathology (dose, 100 mg/kg of body weight), as well as and thus less useful as sunscreen agents. Moreover, several
present in sunscreen formulations reported in Table 2 should damage (71, 72). Accordingly, PABA was taken off the mar-
(62) reported an innovative non-invasive method that uses skin reactions to be 8% or greater and thus its discontinued
formulations (Table 2). and increase the permeation and/or penetration of these
Monograph for sunscreens at a concentration of up to 12%, photoallergenics. For instance, Karlsson et al. (109) noted
Table 2: (i) cinoxate, (ii) dioxybenzone, (iii) ensulizole, (iv) found extensively in sunscreen formulations but, unlike the
only homosalate and octisalate (81), and octinoxate (81–84) it a suitable substrate to absorb incident broadband UV solar
have been evaluated for human absorption, albeit with signif- radiation (110). Oxybenzone is fairly photostable for several
unteers. They discovered that ca. 4% of oxybenzone was
in more than 80% of urine samples of healthy Danish chil-

Methods (brief)

samples following a 5-day exposure of humans with healthy
preparations and non-parenteral medicines; in addition, its various samples. Bottom panel: illumination with 0.2% ZnO for 0,
dered samples. formulations, or else the integrity of the coating on TiO2
that all sunscreen TiO2 samples extracted from commercial radicals on DNA.
However, the TiO2 samples extracted from commercial sun- below) compared to non-modified specimens when exposed
than ∼ 90% (30 min). By contrast, the R22B sample com-
linear (L) forms of DNA plasmids caused by (top panel) UVA/UVB fied R9A sample: cell death was complete after 10 min of
samples; and (lower panel) with R20B, R20A, R22B and R22A tita-
use (10, 74–77). Additionally, analyses of urine samples and octocrylene (95) have shown similar hormonal effects
in more than 80% of urine samples of healthy Danish chil-
zone levels of up to 81 ng/mL in urine samples and up to
H H In their 2008 study, Janjua and coworkers (82) sampled
(MAAs) found in many marine and freshwater organisms
modifying, for example, some of the critical features of the MAAs are low-weight, are water-soluble, are thermally and
MAAs cyclohexenimine basic structure: namely, cycle size, photochemically stable, and are non-fluorescent compounds
In particular, these MAAs should prove very useful in Representative systems illustrated in Fig. 18 were evaluated
(4-MBC; known also as enzacamene, eusolex 6300 and parsol 5000) (MAAs) based on the cyclohexenimine structure, where R2 is a car-
MAAs outclassed most of the commercially available UV

Implications

This page makes the source discoverable for category-level evidence routing. Values remain source-native and should be used only with the stated matrix, species, basis, geography, and censoring context from the paper. The page does not convert total mercury to methylmercury or use total arsenic as inorganic arsenic.

Wiki pages this source may touch

Verification notes

Identity check: DOI, raw handle, candidate cite-key, and SHA-256 were compared against existing wiki/sources/ pages before creation.
Full-PDF read: pdftotext -layout was run on the full PDF twice; extracted text hashes matched before the page was written.
Numeric verification: numeric/table-bearing lines were selected mechanically from the verified extraction and preserved without unit conversion or rounding.
Brand firewall: the worker skips PDFs when extracted numeric lines appear brand/manufacturer-sensitive; this page contains category-level or species-level evidence only.
HMTc firewall: no threshold, percentile, pass/fail, clean/dirty, or certification math is stated.

Update history

The five most recent substantive edits to this page, classified major (evidence or structure moved), correction (a published value or statement was wrong and has been fixed), or minor (narrative rewritten without changing the underlying evidence). Each description is derived from what the edit did to this page; the linked commit is the authoritative record, routine regeneration passes are excluded, and 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.

Commit	Date	Change	Description
b01ec52c	2026-08-04	major	2 sections added
d49e450f	2026-08-03	major	5 sections added; narrative text revised