Abstract:
Braiding hair extensions are widely used consumer beauty products often worn for
extended periods and handled frequently during installation and daily styling. Use is
particularly widespread among Black women and girls, which promotes the
importance of assessing product safety and communicates some environmental-
justice relevance. Extensions are often in close contact with the face and hands and
may be handled by stylists and end users for hours at a time. Potential for toxicant
residue to transfer and incidental ingestion, particularly in children, has recently
garnered more attention in Black beauty communities.
Lead (Pb) is a well-characterized toxicant with no known safe exposure threshold for
neurodevelopmental effects (EPA, 2025). Although regulatory actions have
significantly reduced Pb in fuels, paint, and plumbing, low-level Pb still appears in
some consumer products through pigments/dyes, plastic stabilizers, and recycled
content streams (EPA, 2025). In matrices such as synthetic fibers and blended
materials, trace Pb can originate from colorants, processing additives, or supply-
chain variability (CDC et al., 2024). For products that are frequently touched, potential
exposure routes include hand-to-mouth transfer, indirect dust contamination, and
residue transfer during styling. Dermal uptake of inorganic Pb is limited, but repeated
handling remains a practical concern (Leigh-Ann Jackson, 2025; Niemeier et al., 2022).
For communities with high usage of these products, even small, repeated exposures
are important to characterize so that risk communication and safer-product
guidance can be grounded in evidence (Gruenstein et al., 2021; Thomas, 2023) .
Despite growing interest within recent years, data specific to braiding hair extension
toxicants remains limited. Existing testing is not comprehensive and estimates of
both frequency (how often Pb is present) and magnitude (typical concentrations)
vary. Further, it is unclear whether product characteristics, such as fiber type (Natural
vs. Synthetic), synthetic subtype (e.g., Kanekalon vs. Non-Kanekalon), hair color
(Natural vs. Non-natural), price tier (Budget, Core, Premium), or child-directed
marketing, are meaningfully associated with measured Pb at the low levels reported
to date. Finally, while handheld X-Ray Fluorescence analyzer (XRF) for screening
consumer products is growing (Ceballos et al., 2025; Fellows et al., 2022; Mokashi et al., 2025), its performance on braiding hair matrices at low concentrations relative to
laboratory methods has not been established to our knowledge. To address these
gaps, we conducted a study of commercial braiding hair products with the following
aims:
Aim 1: Quantify lead Pb concentration in braiding hair products using established laboratory
methods (GFAA).
Characterize the presence and concentration of Pb in ppm (parts per million) in 34
commercial braiding hair products using the laboratory gold standard, Graphite
Furnace Atomic Absorption (GFAA). Summarize detection frequency and product-
level central tendencies and explore associations with product characteristics
(product type, hair color, synthetic subtype, price tier, child marketing), recognizing
that concentrations may be low and frequently fall below the laboratory reporting
limit.
Aim 2: Compare handheld XRF lead measurements to GFAA lab analysis
Evaluate handheld X-ray fluorescence (XRF) as a screening approach in this matrix by
comparing XRF detection flags and concentrations to laboratory results for a paired
analysis and calculate detection-agreement metrics appropriate for low Pb
concentrations.