Zmozinski and colleagues measured total lead and total chromium in eleven coded commercial sunscreens from Porto Alegre, Brazil, by high-resolution continuum source graphite furnace atomic absorption spectrometry with direct solid sampling. Chromium in the direct analysis ranged from 0.10 ± 0.01 to 0.65 ± 0.07 µg/g. Lead ranged from 0.027 ± 0.002 µg/g to 1.75 ± 0.10 µg/g, with two samples printed as bLOQ. The paper does not state whether the products are mineral or organic filters, and it does not identify them as infant products.
Key numbers
Limits of detection and quantification in Table 2 are calculated for a 4.5 mg sample and are printed in µg/kg, not in the µg/g unit of the results. LOD is 3 µg/kg for Pb and 1 µg/kg for Cr. LOQ is 9 µg/kg for Pb and 4 µg/kg for Cr. Characteristic mass is 10 pg for Pb and 2.5 pg for Cr.
Direct-analysis found values from the results table (Cr columns first, then Pb), with the digestion comparison where the table prints one. Units are µg/g.
| Code | Cr found | Cr RSD % | Cr digestion | Pb found | Pb RSD % | Pb digestion |
|---|---|---|---|---|---|---|
| M1 | 0.22 ± 0.02 | 9 | 0.23 ± 0.01 | 0.52 ± 0.04 | 8 | 0.57 ± 0.03 |
| M2 | 0.15 ± 0.01 | 6 | 0.15 ± 0.01 | 0.18 ± 0.01 | 6 | 0.16 ± 0.02 |
| M3 | 0.18 ± 0.02 | 11 | not printed | 1.75 ± 0.10 | 6 | 1.71 ± 0.09 |
| M4 | 0.15 ± 0.01 | 6 | not printed | bLOQ | ||
| M5 | 0.11 ± 0.01 | 9 | not printed | 0.18 ± 0.01 | 6 | not printed |
| M6 | 0.65 ± 0.07 | 11 | 0.69 ± 0.04 | 0.44 ± 0.03 | 7 | 0.46 ± 0.01 |
| M7 | 0.59 ± 0.05 | 9 | not printed | 0.027 ± 0.002 | 7 | not printed |
| M8 | 0.52 ± 0.06 | 11 | not printed | 0.43 ± 0.03 | 7 | 0.42 ± 0.02 |
| M9 | 0.10 ± 0.01 | 10 | not printed | 0.09 ± 0.01 | 11 | not printed |
| M10 | 0.17 ± 0.01 | 6 | not printed | 0.72 ± 0.04 | 5 | not printed |
| M11 | 0.10 ± 0.01 | 10 | not printed | bLOQ |
The authors state that the direct and digestion results are not significantly different at 95% confidence. A Student’s t comparison is printed (Cr t calculated 1.39 against t critical 2.91; Pb t calculated 1.05 × 10−15 against t critical 2.13).
Methods (brief)
About 4.5 mg of sunscreen was analysed by HR-CS DS-GF AAS. A digestion comparison was run on a subset of the same codes. The analytes are total lead and total chromium. Chromium(VI) and lead species were not measured. Samples are coded M1 to M11. SPF values printed for the set are 15, 30, 45, 50, and 100.
Evidence fitness
These are finished-product total-metal measurements on adult-unspecified sunscreens. They support a sun-product occurrence row. They do not support a baby-sunscreen row, a mineral-filter row, or a hexavalent-chromium claim.
Limitations
LOD and LOQ are in µg/kg while results are in µg/g. The two scales differ by a factor of 1000 and must not be read as the same unit. The token bLOQ is kept as printed. It is the text-layer glyph where a less-than sign would be expected, and it is not rewritten as a number. The authors cite ANVISA lead ranges of 10 to 20 µg/g as a regulatory comparison. Those figures are not measurements from this study.
Related evidence
Update history
No substantive edit history is available in this build. The full commit record is available in git.