Ultraviolet protection by summer textiles. Ultraviolet transmission measurements verified by determination of the minimal erythema dose with solar-simulated radiation

Circular economy reinforcement through molecular fabrication of textile wastes with microbial synthesized ZnO nanoparticles to have multifunctional properties

The fibrous wastes generated from the mills of textile production can be recycled and converted into high add-values products to be implemented in several applications. The current study aimed to employ commercial free cellulase enzyme to partially hydrolyze (activate) the polyester cotton blended (PET/C) fibrous wastes by creation functional groups such as OH and COOH on their surfaces. The activated fibrous wastes were then modified by coating with ZnO nanoparticles (ZnO-NPs) biosynthesized by actinobacterial cultures free supernatant. The isolate was identified as Streptomyces pseudogriseolus with accession number of OR574241. The conditions that influence the actino-synthesis of ZnO-NPs were optimized and the product was characterized using spectroscopic vision, FTIR, XRD, TEM and SEM. The characteristic ZnO peaks were obviously observed by EDX analysis with 0.38 and 0.75% (wt%), respectively. TEM analyses proved the nanoscale of ZnO-NPs (5-15 nm) which was followed by cytotoxic evaluation for the produced NPs. Fortunately, the tested actino-ZnO-NPs didn't have any cytotoxicity against human normal fibroblast cell line (BJ1), which means that the product can be safely used in a direct-contact with human skin. The treated PET/C blended waste fabrics coated with ZnO-NPs showed high antimicrobial activity and ultraviolet protection values after functionalization by cellulase. EDX analysis demonstrates the presence of Zn peaks on the coated fabrics compared with their absence in blank and control samples, while SEM images showed the formation of a thin layer of ZnO-NPs on the fabric surface. The obtained smart textile can be applied several needed sectors.

Optical Behavior of Curcuminoid Hybrid Systems as Coatings Deposited on Polyester Fibers

The recent development of the “eco-friendly” current has brought to the attention of researchers natural dyes that are biodegradable, do not cause allergies and generally have anti-UV protection, and antioxidant and antibacterial properties. In this study, we aimed to obtain hybrid materials of the dye–host matrix type, by using the sol–gel process. The silica network was generated by tetraethylorthosilicates and modified with organic siloxane derivatives: phenyltriethoxysilane, 3-glycidoxypropyltriethoxysilane, dimethoxydimethylsilane and dimethoxydiphenylsilane. The nanocomposites obtained by embedding curcumin in siloxane matrices were deposited on polyester fabric and evaluated for their properties, relative to the type of organic network modifier used. Fabrics covered with curcuminoid hybrid systems provide a hydrophobic surface, have fluorescent properties and a UPF +50, and, therefore, they can be used in various fields where it is necessary for textiles to provide signaling, self-cleaning or protection properties against ultraviolet radiation. The coated textile materials have very good resistance properties after several repeated washing cycles, and maintain the original UV protection factor at high values even after washing or during rubbing tests.

Photoprotection by clothing: A review

Clothing is recognized by leading health agencies as a primary method to protect against the harmful effects of photodamage caused by ultraviolet (UV) radiation and visible light. The photoprotective capacity of clothing is commonly measured as the ultraviolet protective factor (UPF). While the technology driving photoprotective clothing has been well-established, there continues to be efforts to discover new materials to improve the UPF of clothing. Here, we show increased Google searches for photoprotective clothing over the last decade, suggesting a high level of public interest in photoprotective clothing. In addition, we investigate the frequency of UPF-graded photoprotective clothing sold by large retail stores featured in Fortune 1000. We review factors that alter the UPF of clothing and describe emerging textile technologies used to increase clothing's photoprotective capacity. Finally, we compare how photoprotective clothing is regulated among different countries, the importance of photoprotective clothing in occupational health, and research in visible light and clothing photoprotection.

Using nano technology for imparting PET/C blended fabric new functional performance properties

This article, discuss the effect of finishing polyester/cotton blended fabric (PET/C) with alkali and Titanium dioxide nanoparticles (TiO2 NPs) simultaneously. The treatment conditions such as NaOH and TiO2 NPs concentrations, reaction temperature and duration will be investigated. The effect of addition NPs on alkaline treatment conditions will prove through weight loss and carboxylic content. The ability of PET/C fabrics for loading with NPs during alkaline treatment was investigated by using SEM, EDX, and FTIR measurements. The effect of finishing of PET/C blended fabric with the suggested method on antimicrobial activity and ultraviolet protection was investigated. The simultaneous finishing of PET/C blended fabrics with alkali and TiO2 NPs showed excellent ultraviolet protection and high antimicrobial activity against Gram-positive ( Bacillus mycoides), Gram-negative ( Escherichia coli), and nonfilamentous fungus ( Candida albicans). The functional performance imparted to PET/C fabrics by the suggested approach are durable in repeated laundering processes, even after five Launder-Ometer washes.

An Added Benefit of Masks During the COVID-19 Pandemic: Ultraviolet Protection

The widespread use of masks during the COVID-19 pandemic presents a new avenue for protecting the lower half of the face from the harms of sun exposure. The increased social acceptability of masks, which may persist post-pandemic, has the potential to impact prevention of photosensitive disorders, photoaging, and skin cancer. The authors sought to review clinically relevant information on the ultraviolet (UV) shielding properties of masks. This synthesis of current research will help physicians counsel patients on optimal mask choices, from both dermatological and public health viewpoints. The variables impacting the UV protection of masks were reviewed, including fabric type, construction, porosity, and color. Other factors related to wear and use such as moisture, stretch, laundering, and sanitization are discussed in the context of the pandemic. Black, tightly woven, triple-layered polyester cloth masks were determined to be optimal for UV protection. The most protective choice against both SARS-CoV-2 and UV radiation is a medical mask worn underneath the aforementioned cloth mask. In order to preserve the filtration capacity of the fabric, masks should be changed once they have become moist. Washing cotton masks before first use in laundry detergents containing brightening agents increases their UV protection. Overall, cloth masks for the public that are safest against SARS-CoV-2 are generally also the most protective against UV damage. People should be encouraged to procure a high-quality mask to simultaneously help reduce the spread of SARS-CoV-2 and shield against sun exposure. Further investigation is needed on the UV-protective properties of medical masks.

What level of photoprotection can be obtained using facial mask? Determining effectiveness using an in vitro method

It has become a general practice worldwide to wear a face mask serving as a barrier against the transmission of pathogens. This has prompted us to investigate whether masks could also protect our skin from UV radiation. We have studied eight masks, four surgical and four "homemade" using an in vitro method. The study demonstrated that they all offered protection against both UVB and UVA radiation. As with clothing, fabric masks offer the highest level of protection against UV radiation.

Synthesis of Novel UV Absorbers Bisindolylmethanes and Investigation of Their Applications on Cotton-Based Textile Materials

Nowadays modified textiles, especially UV-protective, antibacterial and antimicrobial ones, have become the focus of great interest. In this study, several new UV absorbers, bis(indolyl)methane derivatives, were synthesized and grafted onto polyvinyl alcohol polymer (PVA). Their application properties on cotton-based textile materials were determined; the UV protection factor values of the modified fabrics were measured (UPF); and the antibacterial features of the fabrics were tested.

The influence of the environment and clothing on human exposure to ultraviolet light

Objection

The aim of this study is to determine the effect of clothing and the environment on human exposure to ultraviolet light.

Methods

The ultraviolet (ultraviolet A and ultraviolet B) light intensity was measured, and air quality parameters were recorded in 2014 in Beijing, China. Three types of clothing (white polyester cloth, pure cotton white T-shirt, and pure cotton black T-shirt) were individually placed on a mannequin. The ultraviolet (ultraviolet A and ultraviolet B) light intensities were measured above and beneath each article of clothing, and the percentage of ultraviolet light transmission through the clothing was calculated.

Results

(1) The ultraviolet light transmission was significantly higher through white cloth than through black cloth; the transmission was significantly higher through polyester cloth than through cotton. (2) The weather significantly influenced ultraviolet light transmission through white polyester cloth; transmission was highest on clear days and lowest on overcast days (ultraviolet A: P=0.000; ultraviolet B: P=0.008). (3) Air quality parameters (air quality index and particulate matter 2.5 and 10) were inversely related to the ultraviolet light intensity that reached the earth’s surface. Ultraviolet B transmission through white polyester cloth was greater under conditions of low air pollution compared with high air pollution.

Conclusion

Clothing color and material and different types of weather affected ultraviolet light transmission; for one particular cloth, the transmission decreased with increasing air pollution.

Ultraviolet Protection by Fabric Engineering

Background. The increasing emission of greenhouse gases has evoked the human being to save the ozone layer and minimize the risk of ultraviolet radiation (UVR). Various fabric structures have been explored to achieve desired ultraviolet protection factor (UPF) in various situations. Objective. In this study, the effect of various filament configurations like twisted, flat, intermingled, and textured in multifilament yarns on fabric in different combinations is assessed in order to engineer a fabric of better ultraviolet protection factor (UPF). Methods. In order to engineer a fabric having optimum UV protection with sufficient comfort level in multifilament woven fabrics, four different yarn configurations, intermingled, textured, twisted, and flat, were used to develop twelve different fabric samples. The most UV absorbing and most demanding fibre polyethylene terephthalate (PET) was considered in different filament configuration. Results. The combinations of intermingled warp with flat, intermingled, and textured weft provided excellent UVR protection comparatively at about 22.5 mg/cm2 fabric areal density. The presence of twisted yarn reduced the UV protection due to enhanced openness in fabric structure. Conclusion. The appropriate combination of warp and weft threads of different configuration should be selected judiciously in order to extract maximum UV protection and wear comfort attributes in multifilament woven PET fabrics.

[Update on photoprotection in children]

Children are one of the population groups in which the photo-protection must be maximised. Firstly, because they take part in outdoor activities more often than adults. Secondly, because the principal risk factor for all types of skin cancer is ultraviolet radiation, and in particular, cumulative exposure during childhood. Hence, decreasing exposure to ultraviolet radiation in childhood has the potential to significantly lower the incidence of most forms of skin cancer. Photoprotection includes behavioural measures to protect the skin from sun exposure, e.g. sun protective clothes, hats, sunglasses, and sunscreens. It is necessary to provide information on aphotoprotection to parents, and, above all, to children, using educational campaigns to increase knowledge of photoprotection to help change attitudes towards sun exposure. Dermatologists and Paediatricians play a essential role in this educational work. In this article we review the latest information regarding paediatric sun protection, the new sunscreens, and the recent sun protection educational programs.

On the relationship between fabric processing and ultraviolet radiation transmission

BACKGROUND

The relationship between a fabric's physical characteristics and ultraviolet radiation transmission has been widely discussed in the literature. However, very few studies have taken into account the 'fiber-fabric construction-processing' history of fabrics into consideration to fully elucidate the ultraviolet (UV) protection abilities of fabrics. This study reports the effect of fabric processing treatments, both chemical and bio-chemical, on the transmission of UV radiation (UVR) through selected white and un-dyed fabrics.

METHODS

Eight woven fabrics were selected to illustrate the effect of chemical processing on UVR transmission. Fabrics were characterized with respect to fiber chemistry, fabric construction, weight, thickness, and chemical processing history. Influence of fabric characteristics and processing on Ultraviolet protection factor (UPF) were studied. Furthermore, a knit bleached cotton T-shirt fabric was treated bio-chemically and the effect of bio-chemical processing on UPF was investigated.

RESULTS

Physical characteristics of fabrics such as thickness, weight and cloth cover were shown to be only partly useful in explaining the UV protective abilities of fabrics in that the data show anomalies when only physical features of fabrics are considered without considering processing history. However, by taking into account the processing history of fabrics, the UPF values obtained can be fully explained.

CONCLUSION

Chemical processing methods such as desizing and bleaching have a deleterious effect on UV transmission through fabrics. Bio-chemical processing such as the use of enzymes is comparatively benign and does not adversely impact the UV protective ability of cotton fabric.

Photoprotection

Sun exposure is the main cause of photocarcinogenesis, photoageing, and photosensitivity; thus, photoprotection is an important issue. In a skin cancer prevention strategy, behavioural measures--eg, wearing sun protective clothes and a hat and reducing sun exposure to a minimum--should be preferred to sunscreens. Often this solution is deemed to be unacceptable in our global, outdoor society, and sunscreens could become the predominant mode of sun protection for various societal reasons (eg, healthiness of a tan, relaxation in the sun). The application of a liberal quantity of sunscreen has been shown to be by far the most important factor for effectiveness of the sunscreen, followed by the uniformity of application and the specific absorption spectrum of the agent used. The sunscreen market--crowded by numerous products--shows various differences worldwide. Nevertheless, sunscreens should not be abused in an attempt to increase time in the sun to a maximum. Controversies about safety of sunscreens and clinical recommendations are discussed.

The European standard for sun-protective clothing: EN 13758

Clothing is considered one of the most important tools for sun protection. Contrary to popular opinion, however, some summer fabrics provide insufficient ultraviolet (UV) protection. The European Committee for Standardization (CEN), has developed a new standard on requirements for test methods and labelling of sun-protective garments. This document has now been completed and is published. Within CEN, a working group, CEN/TC 248 WG14 'UV protective clothing', was set up with the mission to produce standards on the UV-protective properties of textile materials. This working group started its activities in 1998 and included 30 experts (dermatologists, physicists, textile technologists, fabric manufacturers and retailers of apparel textiles) from 11 European member states. Within this working group, all medical, ethical, technical and economical aspects of standardization of UV-protective clothing were discussed on the basis of the expertise of each member and in consideration of the relevant literature in this field. Decisions were made in consensus. The first part of the standard (EN 13758-1) deals with all details of test methods (e.g. spectrophotometric measurements) for textile materials and part 2 (EN 13758-2) covers classification and marking of apparel textiles. UV-protective cloths for which compliance with this standard is claimed must fulfill all stringent instructions of testing, classification and marking, including a UV protection factor (UPF) larger than 40 (UPF 40+), average UVA transmission lower than 5%, and design requirements as specified in part 2 of the standard. A pictogram, which is marked with the number of the standard EN 13758-2 and the UPF of 40+, shall be attached to the garment if it is in compliance with the standard. The dermatology community should take cognizance of this new standard document. Garment manufacturers and retailers may now follow these official guidelines for testing and labelling of UV-protective summer clothes, and the sun-aware consumer can easily recognize garments that definitely provide sufficient UV protection.

Incorporation of the sunscreen agent, octyl methoxycinnamate in a cellulosic fabric grafted with β-cyclodextrin

The aim of the study was to investigate the incorporation of the sunscreen agent, octyl methoxycinnamate into cyclodextrin cavities covalently bound to cloth fibres. Tencel, a cellulosic fabric, was grafted with beta-cyclodextrin molecules through reaction with monochlorotriazinyl-beta-cyclodextrin (beta-CDMCT). The finished and untreated textiles were soaked in water-methanol mixtures containing 2% (v/v) of sunscreen agent and subsequently subjected to several washing cycles. The unmodified and modified fabrics were characterized by UV spectrophotometry and thermogravimetric analysis. The level of octyl methoxycinnamate entrapped in the Tencel tissue was determined by high-performance liquid chromatography and was found to be much higher (0.0203%, w/w) for the textile functionalised with beta-CDMCT compared to the unmodified fabric (0.0025%, w/w). In addition, spectrophotometric assessment of UV transmission through the fabric samples using the Transpore test showed that the in vitro sun protection factor of the textile support was markedly enhanced (3.2-fold increase) by impregnation with octyl methoxycinnamate of the beta-CDMCT grafted textile. Hence, even after repeated washings, the beta-CD finished fabric exhibits higher sunscreen agent retention and photoprotective properties than the unmodified textile material.

Photoprotection

Many agents affect the transmission of ultraviolet light to human skin. These include naturally occurring photoprotective agents (ozone, pollutants, clouds, and fog), naturally occurring biologic agents (epidermal chromophores), physical photoprotective agents (clothing, hats, make-ups, sunglasses, and window glass), and ultraviolet light filters (sunscreen ingredients and sunless tanning agents). In addition, there are agents that can modulate the effects of ultraviolet light on the skin (antioxidants and others). All of the above are reviewed in this article.

LEARNING OBJECTIVE

At the conclusion of this learning activity, participants should be able to provide an overview of all aspects of photoprotection.

Photoprotection by clothing

Wearing of clothing, hats, and sunglasses to protect from exposure to sunlight should be part of a package of protection. Clothing specifically designed to avoid exposure is now available and recently standards have been published in several countries to measure the degree of protection. The ultraviolet protection factor (UPF) is likely to be as ubiquitous in clothing aisles as the sun protection factor (SPF) is now in the sunscreen aisle of your local department store.

Comparison of methods: determination of UV protection of clothing

Based on spectrophotometric measurements and mathematical calculations, the ultraviolet (UV) protection factor of a textile is determined in vitro. This technique is the most established test method for the determination of UV protection of a garment. However, the validity and practicality of the in vitro UV protection factor (UPF) determined in the laboratory has been a controversial issue with regard to its significance in the field. Several studies have verified the in vitro UPF by comparing it with various in vivo test protocols using solar-simulated radiation for the determination of the minimal erythema dose. The data inconsistency between these studies is certainly due to different methodology. Furthermore, UV dosimetry is a suitable method for quantifying UV transmission through a garment. Chemical dosimeters (e.g. polysulfone films) and biological UV detector films have been used in in vivo-simulated studies in the form of small portable badges monitoring solar UV transmittance through garments on manikins and mobile subjects. As sunlight consists to a considerable extent of diffuse radiation, which is more scattered and absorbed by the fabric than direct radiation, UPF values obtained by measurements in real exposure situations are usually higher than those obtained by conventional in vitro and in vivo testing with collimated radiation beams. Thus the discrepancy between laboratory-based testing and field-based measurements may be due to different radiation geometry of UV sources. Taken together, the in vitro method is the most practicable and inexpensive method for routine measurements of UPF, but dosimetry seems to be a highly useful method for determining the UPF in real exposure situations.

Ultraviolet protection factor of fabrics: comparison of laboratory and field-based measurements

BACKGROUND/PURPOSE

Spectrophotometry has become an accepted laboratory-based method for the determination of the ultraviolet protection factor (UPF) of fabrics. However, the validity of the UPF determined in the laboratory has been a controversial issue with regard to its significance in the field. To compare UPF values obtained by spectrophotometry, determination of the minimal erythema dose (MED), and biological dosimetry, we conducted laboratory and field-based measurements on various fabric materials.

METHODS

One cotton, two viscose, and two polyester fabrics were enrolled into the study. Spectrophotometric (SP) testing was performed in accordance with the European standard. In vivo "on skin" (IV) testing on human subjects was performed with and without fabric protection. For determination of MED, a solar-simulator was used. In another part of the study, biological dosimetry (BD) testing was employed for laboratory testing with solar-simulated radiation (laboratory BD testing) as well as field-based measurements with natural sunlight in stationary (stationary BD testing) and "real life" exposure situations (mobile subject BD testing). For field-based measurements one light-weight polyester fabric was selected.

RESULTS

The differences of the mean UPF values obtained by the laboratory-based methods were significant (MANOVA; P = 0.05), except for fabric no. 2 (MANOVA; P = 0.097). In 4 of the 5 fabrics tested, UPF values obtained by IV testing were significantly lower than those obtained by SP testing (t-test; P = 0.05). In 3 fabrics, SP testing revealed significantly higher UPF values in comparison to laboratory BD testing (t-test; P = 0.05). The differences of UPF values obtained by the laboratory and field-based measurements employed for the light-weight polyester fabric were significant (ANOVA; P = 0.05). In comparison to SP testing (UPF 3.8), stationary BD testing resulted in significantly lower (UPF 3.5) and mobile subject BD testing in a significantly higher UPF of 4.4 (t-test; P = 0.05). The UPF obtained by mobile subject BD testing differed significantly from the UPF obtained by stationary BD testing (t-test; P = 0.05).

CONCLUSIONS

Comparison of the presented methods indicates that IV testing generally results in lower UPF values. By contrast BD testing in "real life" exposure situations reveals relatively high UPF values. Although an overestimation of the spectrophotometrically measured UPF has been observed in comparative laboratory testing, UPF values obtained by field-based measurements are in relatively good agreement, or even surpass UPF values obtained by spectrophotometry. It is, therefore, suggested that SP testing provides "safe" UPF values which may be also valid in extreme real exposure situations. Biological UV dosimetry is, however, a promising alternative method for UPF testing: the test is easily performed in realistic exposure situations, the test is relatively inexpensive, and the measurements are valid.

Protection against ultraviolet radiation by commercial summer clothing: need for standardised testing and labelling

BACKGROUND

The use of clothing as a means of sun protection has been recommended in recent education campaigns. Contrary to popular opinion, however, some fabrics provide insufficient ultraviolet (UV) protection.

MATERIAL AND METHODS

We investigated 236 apparel textiles of the spring/summer collections 2000 and 2001. In accordance with the forthcoming European standard the UV protection factor (UPF) of the fabrics was determined spectrophotometrically.

RESULTS

Seventy-eight (33%) fabrics had UPF < 15, 45 (19%) had UPF = or > 15 and < 30, and 113 (48%) had UPF = or > 30 (30+). More than 70% of the wool, polyester, and fabric blends, and only less than 30% of the cotton, linen, and viscose fabrics had UPF values of 30+. Fabrics with black, navy-blue, white, green, or beige colours provided most frequently UPF values of 30+.

CONCLUSIONS

It is difficult for the sun-aware consumer to choose the 'right' garment, with a third of summer clothing providing insufficient UV protection and only half of the fabrics having UPF 30+, the UPF recommended by the European standard. Therefore, apparel summer fabrics should be measured and labelled in accordance with a standard document.