Textile Testing

Zhu, Hongkai, and Kurunthachalam Kannan. Science of The Total Environment 710 (2020): 136396.

Melamine-based resins are widely used in fabrics to impart flame retardancy, heat resistance, and wrinkle resistance. However, there is limited knowledge about the levels of melamine and its derivatives in textiles.

In this study, the concentrations of melamine, melam, melem, and cyanuric acid were determined in 77 textile samples and baby clothing. All textile samples contained one or more target analytes, with concentrations of melamine, melam, melem, and cyanuric acid ranging from 1.19 to 81,800, 3.21 to 17,800,<1.20 to 25,700, and <0.50 to 550 ng/g, respectively. Melamine was the predominant compound, constituting 52% of the total concentration of the four analytes (∑melamine). A significant positive correlation was found among the concentrations of melamine and its three derivatives (0.347 < r < 0.862, p < .01). The concentration of ∑melamine in cotton fabrics (mean: 10,500 ng/g) and cotton clothing (10,200 ng/g) was significantly higher than in synthetic fabrics (1,380 ng/g) and socks (40.0 ng/g) (p < .01). Simulated laundry experiments indicated that washing once with water could remove 76-90% of the melamine from the garments. The calculated skin exposure doses of melamine and cyanuric acid were three to four orders of magnitude lower than reference values.

Zhang, Zhuomin, Cheng Zhao, and Gongke Li. Talanta 154 (2016): 346-353.

Achieving reproducible signals is crucial for enhancing the precision and accuracy of Surface-Enhanced Raman Scattering (SERS) techniques, as well as for expanding the application of SERS in the rapid analysis of complex matrices in real samples.

In this study, a novel Au@hydroxyl-functionalized polystyrene (Au@PS-OH) substrate was prepared using atomic transfer radical polymerization and chemical assembly methods, demonstrating good potential for rapid continuous multi-sample analysis in combination with SERS technology. The Au@PS-OH substrate, with a regular nanostructure morphology and a large number of Au nanoparticles uniformly and stably fixed on its surface, exhibited excellent anti-aggregation capability even in strongly alkaline or acidic test solutions, along with good mechanical and chemical stability. Moreover, the superior hydrophobicity of the Au@PS-OH substrate allowed multiple sample droplets to maintain stable, uniformly spherical shapes, with contact angles similar to that of the substrate, ensuring the reproducibility of the SERS optical path and signals during actual sequential analysis.

Subsequently, an SERS analytical method based on Au@PS-OH was established and applied for the sequential determination of trace 4-aminobenzenesulfonic acid in various textiles. The results were satisfactory, with the measured amounts of trace 4-aminobenzenesulfonic acid in black wool, green wool, and yellow fiber cloth calculated as 106.4, 120.9, and 140.8 mg/kg, respectively. The recovery rates ranged from 76.0% to 118.9%, and the relative standard deviations were between 1.6% and 5.1%. This SERS method is expected to be suitable for the rapid on-site analysis of multiple samples within a short time.

Zhu, Hongkai, and Kurunthachalam Kannan. Environmental Pollution 265 (2020): 114940.

Per- and polyfluoroalkyl substances (PFAS) are used in specialty/functional textiles to provide oil, water, and stain resistance. However, little is known about the presence of PFAS in textiles, including baby clothing.

In this study, 13 perfluoroalkyl acids (PFAAs), including four perfluoroalkyl sulfonic acids (PFSA; C4-C10) and nine perfluoroalkyl carboxylic acids (PFCA; C4-C12), were determined in 160 textile samples. Two extraction methods were employed: one involving simple solvent extraction (i.e., pre-oxidation), and the other involving oxidation treatment of the textile extracts (i.e., post-oxidation). The total concentration of 13 PFAAs (i.e., ∑PFAA) in pre-oxidation textile extracts ranged from < LOD to 63.7 μg/m² (< LOD–285 ng/g), with an average of 3.18 μg/m² (14.2 ng/g). The highest ∑PFAA concentration was found in flame-retardant textiles (n = 23; average: 13.3 μg/m²; 59.4 ng/g), followed by waterproof textiles (n = 56; 2.88 μg/m²; 12.9 ng/g) and baby clothing (n = 81; 0.521 μg/m²; 2.33 ng/g). C4–C10 PFCAs accounted for at least three-quarters of the ∑PFAA content in our textile samples. The ∑PFAA concentration in textile extracts analyzed post-oxidation was ten times higher than that in pre-oxidation extracts, indicating the use of PFAA precursors in textiles. Precursor compounds generating C4–C5 PFCAs were found to be more prevalent than those producing PFOA. The calculated PFAA exposure doses for infants were at least one to two orders of magnitude lower than the reference doses suggested by the U.S. Environmental Protection Agency.