RESUMO

In recent years, domestic laundry has been recognized as a relevant source of microfiber (MF) pollution to aquatic environments. Nevertheless, the MF emissions from industrial washing processes in real world scenarios have not been quantified. The aim of this study was to quantify the MF emissions from 3 industrial washing processes (rinse wash, acid wash and enzymatic wash) commonly employed in the manufacturing process of blue jeans. The blue jeans were characterized by ATR-FT-IR, SEM and TGA to study the morphology, the polymer chemical identity and the proportion of synthetic and natural fibers, respectively. The MF emissions were quantified as the MF mass and number emitted per washed jean. All the industrial washing processes released a majority of synthetic MF. The enzymatic wash produced the highest amount of MF, with 1423 MF per gram of fabric (MF/g) equivalent to 381.7 MF grams per gram of fabric (MF g/g), followed by the acid wash with 253 MF/g equivalent to 142.7 MF g/g and lastly the rinse wash with 133 MF/g equivalent to 62.3 MF g/g. Statistically significant differences between the MF sizes for all washing processes were found when evaluating the emissions by MF/g, however, the previous trend was not found for MF g/g. Moreover, the total MF emissions of an industrial washing process of a pair of blue jeans during its manufacture process are up to 10.95 times higher than the reported domestic washing estimates performed by the consumer available in the published literature. We demonstrate that studying industrial washing procedures of textile garments will improve the accuracy of the current estimates of MF emissions available in published reports, which will ultimately aid in the development of regulations for MF emissions at an industrial level.

Assuntos

Lavanderia , Plásticos , Microplásticos , Espectroscopia de Infravermelho com Transformada de Fourier , Lavanderia/métodos , Têxteis

RESUMO

As part of our ongoing research into the clear daytime sky's visible structure, we analyze over 1,500 skylight spectra measured during a seven-month period in Granada, Spain. We use spectral radiances measured within 3 degrees fields of view (FOV's) to define colorimetric characteristics along four sky meridians: the solar meridian and three meridians at azimuths of 45 degrees, 90 degrees, and 315 degrees relative to it. The resulting clear-sky chromaticities in 44 different view directions (1) are close to but do not coincide with the CIE daylight locus, (2) form V-shaped meridional chromaticity curves along it (as expected from theory), and (3) have correlated color temperatures (CCT's) ranging from 3,800 K to infinity K. We also routinely observe that sky color and luminance are asymmetric about the solar meridian, usually perceptibly so. A principal-components analysis shows that three vectors are required for accurate clear-sky colorimetry, whereas six are needed for spectral analyses.