Five hair dyes sold in Ibadan were digested and measured by ICP-OES for 22 elements. Table 3 is the concentration table and was transcribed in full for each code. Cesium is the dominant reported value, from 0.000 ppm in the gold dye to 22561.900 ppm in the white dye, which pulls the all-element averages to 1074.149, 882.715, 720.246, 689.242, and 7.845 ppm. Lead in the table is 0.468 to 1.932 ppm. Several cells are negative, including mercury, molybdenum, sulfur, and antimony. The narrative ranges for arsenic, cobalt, copper, and zinc do not all match Table 3; the table cells were used for the per-sample rows.
Key numbers
| Analyte | Matrix | Value | Unit | Statistic | N | Where |
|---|---|---|---|---|---|---|
| multi-element average | mean of measured PTEs in hair dye A4 | 1074.149 | ppm | mean | 1 product | p.PDF p.9 (printed 125) |
| multi-element average | mean of measured PTEs in hair dye A1 | 882.715 | ppm | mean | 1 product | p.PDF p.9 (printed 125) |
| multi-element average | mean of measured PTEs in hair dye A5 | 720.246 | ppm | mean | 1 product | p.PDF p.9 (printed 125) |
| multi-element average | mean of measured PTEs in hair dye A2 | 689.242 | ppm | mean | 1 product | p.PDF p.9 (printed 125) |
| multi-element average | mean of measured PTEs in hair dye A3 | 7.845 | ppm | mean | 1 product | p.PDF p.9 (printed 125) |
| B | five hair dyes | 0.29 | ppm | mean | 5 | p.PDF p.6 (printed 122) |
| B | five hair dyes | 0.18-0.4 | ppm | range | 5 | p.PDF p.6 (printed 122) |
| Fe | five hair dyes | 7.5128 | ppm | mean | 5 | p.PDF p.7 (printed 123) |
| Fe | five hair dyes | 2.361-21.258 | ppm | range | 5 | p.PDF p.7 (printed 123) |
| Ag | USFDA Ag in color additives | 0.10-0.20 | ppm | regulatory_limit | p.PDF p.5-9 | |
| As | USFDA As | 3.00 | ppm | regulatory_limit | p.PDF p.5-9 | |
| B | USFDA boron as an impurity | 10-20 | ppm | regulatory_limit | p.PDF p.5-9 |
Methods (brief)
ICP-OES wavelengths are listed in Table 2, with a stated dilution of 20 and 1000 μg/mL stock standards. Questionnaires from 250 adults in a southwest local government area of Ibadan were used for exposure factors. Tables of hazard quotients and lifetime cancer risk were not transcribed cell by cell.
Detection and reporting: No LOD or LOQ is stated. Some Table 3 results are negative (Hg, Mo, S, Sb), which were copied as printed.
Basis: Total element in the hair-dye product, ppm. Not a migration test. Arsenic and chromium were not speciated. Hazard quotients and lifetime cancer risks are models.
Evidence fitness
This source can support: Total-element ICP-OES results for five Ibadan-market hair dyes as printed in Table 3; The paper’s stated comparison limits.
It cannot support: A reconciled narrative-versus-table dataset; Speciation of As, Cr, or Hg; A demonstrated LOD; Brand names in summary prose.
Limitations
Two different digestion procedures are described and it is not stated which one produced Table 3. No detection limit is given, so negative concentrations cannot be interpreted as censored zeros; they are copied as printed. Narrative colour labels sometimes disagree with Table 1 (for example zinc and copper). Sulfur and silicon are in Table 3 but are not metals. HQ and LCR tables (printed Tables 4-9) were not fully transcribed; one ingestion LCR range from the prose was entered. Limits the paper attributes to the USFDA were entered as the paper states them, including cases where two different lead numbers (10 and 20 ppm) and two different nickel numbers (0.1 and 5 ppm) are both printed.
Related evidence
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