Unexpected radiation hazard in dyes of textiles

Textile dyes are among the most problematic pollutants because of their toxicity on several organisms and ecosystems. Many of the chemicals used in the textile industry may represent some health concerns. The determination of the radioactivity in textile dyes is therefore very important for both human health and environment. The study was designated to determine, for the first time, the values of (238)U, (232)Th and (40)K in nine different dyes employed in the textile industry using gamma spectrometry with a Hyper Pure Germanium (HPGe) detector. The mean activity concentrations of (238)U, (232)Th and (40)K were 29.37 ± 4.48, 1.15 ± 0.13 and 565 ± 4 Bq/kg, respectively. The calculated radium equivalents for all samples were lower than the maximum admissible value (370 Bq/kg). The absorbed dose rates due to the natural radioactivity of the investigated samples ranged from 2.94 ± 0.05 to 166 ± 3 nGy/h. So, the absorbed dose rates for all samples of textile dyes were lower than the international recommended value (55 nGy/h) except the yellow dye (166 ± 3 nGy/h), which recorded a significant radiological hazard. The external hazard index was also calculated. Conclusively, the results have indicated that the textile dyes may possess a measurable amount of radioactivity that should be taken into account. Therefore, safety rules and precautions should be applied for dyes used in the textile industry and for people working in this field.