Cotton T-shirt Research Articles

Clothing reduces the sun protection factor of sunscreens

Individuals are recommended to wait for 20 min following sunscreen application before dressing. However, this is probably seldom done in daily life, and therefore we investigated how dressing earlier than 20 min after application affected the sun protection factor (SPF). To determine the SPF of a sunscreen applied at different amounts at 4, 8 and 20 min before dressing. An organic sunscreen was used on the backs of 22 healthy volunteers. Before SPF testing, participants wore a cotton T-shirt for 60 min after the test areas had been uncovered for 4, 8 or 20 min after sunscreen application. The SPF was also tested on unclothed skin. The median SPF was 11.7 (2 mg cm(-2)), 5.7 (1 mg cm(-2)) and 3.3 (0.5 mg cm(-2)) for unclothed skin, and 8.1 (2 mg cm(-2)), 4.8 (1 mg cm(-2)) and 2.2 (0.5 mg cm(-2)) following an interval of 8 min before dressing. The SPF was similar for time intervals of 20 and 8 min when the amount was 1 mg cm(-2) (P = 0.48) and 2 mg cm(-2) (P = 0.56). For 0.5 mg cm(-2) there was no difference between skin clothed after 20 min and unclothed skin (P = 0.19), nor between skin clothed after 4 min and after 8 min (P = 0.28). When sunscreens are applied at amounts of 1 and 2 mg cm(-2) the time between sunscreen application and dressing can be as little as 8 min. When less sunscreen is used the SPF is insensitive to the length of time between application and dressing.

Elemental analysis of white cotton fiber evidence using solution ICP-MS and laser ablation ICP-MS (LA-ICP-MS)

The purpose of this research is to investigate a method for the forensic elemental analysis of cotton fibers for the purpose of increasing the discrimination between otherwise similar cotton evidence using microwave digestion inductively coupled plasma mass spectrometry (ICP-MS) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). A quadrupole ICP-MS and UV laser ablation (266 nm) instruments were used for the analysis. A cotton standard reference material (IAEA V-9) was used to validate the developed methods producing good accuracy with typically <10% bias and good precision (typically <5% RSD) for the element list: 25Mg, 27Al, 55Mn, 57Fe, 88Sr and 137Ba. It was found that the LA-ICP-MS method resulted in improved precision over the solution ICP-MS method. Twenty-four raw cotton samples and five white cotton T-shirts were analyzed with the developed methods. It was also found that all the raw cotton samples from different sources were distinguishable from each other, as were all the cotton T-shirts resulting in zero type I errors and zero type II errors for the pairwise comparisons. The laser ablation method was slightly faster than the solution-based analysis, requiring ∼3 h for the laser analysis of 10 samples vs. 3.5 h for the solution analysis, including sample preparation time. One additional advantage of the LA-ICP-MS method was the extremely low sample consumption (∼1.75 μg were consumed vs. 250 mg for the solution-based method) and the fact that the LA samples are amenable for reanalysis.

A spatially explicit life cycle inventory of the global textile chain

Background, aim, and scopeLife cycle analyses (LCA) approaches require adaptation to reflect the increasing delocalization of production to emerging countries. This work addresses this challenge by establishing a country-level, spatially explicit life cycle inventory (LCI). This study comprises three separate dimensions. The first dimension is spatial: processes and emissions are allocated to the country in which they take place and modeled to take into account local factors. Emerging economies China and India are the location of production, the consumption occurs in Germany, an Organisation for Economic Cooperation and Development country. The second dimension is the product level: we consider two distinct textile garments, a cotton T-shirt and a polyester jacket, in order to highlight potential differences in the production and use phases. The third dimension is the inventory composition: we track CO2, SO2, NO x , and particulates, four major atmospheric pollutants, as well as energy use. This third dimension enriches the analysis of the spatial differentiation (first dimension) and distinct products (second dimension).Materials and methodsWe describe the textile production and use processes and define a functional unit for a garment. We then model important processes using a hierarchy of preferential data sources. We place special emphasis on the modeling of the principal local energy processes: electricity and transport in emerging countries.ResultsThe spatially explicit inventory is disaggregated by country of location of the emissions and analyzed according to the dimensions of the study: location, product, and pollutant. The inventory shows striking differences between the two products considered as well as between the different pollutants considered. For the T-shirt, over 70% of the energy use and CO2 emissions occur in the consuming country, whereas for the jacket, more than 70% occur in the producing country. This reversal of proportions is due to differences in the use phase of the garments. For SO2, in contrast, over two thirds of the emissions occur in the country of production for both T-shirt and jacket. The difference in emission patterns between CO2 and SO2 is due to local electricity processes, justifying our emphasis on local energy infrastructure.DiscussionThe complexity of considering differences in location, product, and pollutant is rewarded by a much richer understanding of a global production–consumption chain. The inclusion of two different products in the LCI highlights the importance of the definition of a product's functional unit in the analysis and implications of results. Several use-phase scenarios demonstrate the importance of consumer behavior over equipment efficiency. The spatial emission patterns of the different pollutants allow us to understand the role of various energy infrastructure elements. The emission patterns furthermore inform the debate on the Environmental Kuznets Curve, which applies only to pollutants which can be easily filtered and does not take into account the effects of production displacement. We also discuss the appropriateness and limitations of applying the LCA methodology in a global context, especially in developing countries.ConclusionsOur spatial LCI method yields important insights in the quantity and pattern of emissions due to different product life cycle stages, dependent on the local technology, emphasizing the importance of consumer behavior. From a life cycle perspective, consumer education promoting air-drying and cool washing is more important than efficient appliances.Recommendations and perspectivesSpatial LCI with country-specific data is a promising method, necessary for the challenges of globalized production–consumption chains. We recommend inventory reporting of final energy forms, such as electricity, and modular LCA databases, which would allow the easy modification of underlying energy infrastructure.

Outside in-Forget insulation, there’s more economy in lagging females, says David Newnham

A mild afternoon in late summer – time to catch a last glimpse of the sea. And as Janet and I stroll on the beach, one of us wears a light cotton T-shirt while the other is wrapped in more layers than a Spanish onion. Can you guess which is which?

On the relationship between fabric processing and ultraviolet radiation transmission

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. 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. 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. 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.

Physiological and comfort effects of commercial “wicking” clothing under a bulletproof vest

Ballistic protective gear (“bulletproof” vest), required in law enforcement and some branches of the military, contains thick padding and covers much of the surface area of the user's torso. Bulletproof vest (BV) use poses a compromise between protecting one's life from assault and risking possible harm from heat strain injury. Aside from the danger of heat-related injuries, BV may contribute to severe discomfort problems. Therefore, this study examined the effects of a snug-fitting synthetic shirt designed to wick sweat away from the skin worn under BV. Several physiological and comfort parameters were assessed while wearing two different undergarments on two separate occasions (Under Armour {EC} or cotton t-shirt {CT}). Pre- and post-blood and urine samples were collected for determination of percent change in plasma volume (%ΔPV) and urine-specific gravity (USG). Before exercising, participants inserted a rectal thermocouple for the continuous measurement of core temperature. Also, participants were fitted with several skin thermocouples and a heart rate monitor was placed beneath the undergarment. Next, the participants were dressed in the undergarment, trousers, BV, short-sleeved button up shirt, and a military ballistic helmet. Participants performed a simulated industrial protocol for ∼2 h. Results showed no significant difference between trials (EC vs. CT) for rectal temperature and all skin temperatures except for chest temperature, which was significantly lower while wearing EC. There were also no significant differences between trials for %ΔPV, USG, or heart rate. Furthermore, there were no significant differences between trials for any subjective or comfort measure. Results suggest that EC offers no advantage in cooling the wearer over CT. Additionally, even though there were no significant differences between ensembles for subjective measures, trends were observed with EC being perceived as being more comfortable.

Enteric Virus Survival during Household Laundering and Impact of Disinfection with Sodium Hypochlorite

This study was conducted to determine whether enteric viruses (adenovirus, rotavirus, and hepatitis A virus) added to cotton cloth swatches survive the wash cycle, the rinse cycle, and a 28-min permanent press drying cycle as commonly practiced in households in the United States. Detergent with and without bleach (sodium hypochlorite) was added to washing machines containing sterile and virus-inoculated 58-cm2 swatches, 3.2 kg of cotton T-shirts and underwear, and a soiled pillowcase designed to simulate the conditions (pH, organic load, etc.) encountered in soiled laundry. The most important factors for the reduction of virus in laundry were passage through the drying cycle and the addition of sodium hypochlorite. Washing with detergent alone was not found to be effective for the removal or inactivation of enteric viruses, as significant concentrations of virus were found on the swatches (reductions of 92 to 99%). It was also demonstrated that viruses are readily transferred from contaminated cloths to uncontaminated clothes. The use of sodium hypochlorite reduced the number of infectious viruses on the swatches after washing and drying by at least 99.99%. Laundering practices in common use in the United States do not eliminate enteric and respiratory viruses from clothes. The use of bleach can further reduce the numbers of enteric viruses in laundry.

Simple Respiratory Mask

Simple Respiratory Mask

The population of coloured textile fibres in domestic washing machines

A population survey was carried out to analyse examples of the coloured fibre population that may be expected to exist in both front- and top-loading domestic washing machines during Spring, in Sydney, Australia. White cotton T-shirts were washed both individually, and with a normal household wash load, then taped to recover extraneous fibres transferred during the wash cycle. Twelve thousand one hundred and seventy-eight fibres were classified according to length, colour and generic class. Cotton fibres were most prevalent (69.4%), followed by man-made fibres (24.2%). The most common colour/generic class combinations were black/grey cotton (27%), blue cotton (20%) and red cotton (15.6%). Other combinations generally represented under 2% of the total fibre population. Two thirds (65.9%) of the recovered fibres were under 2 mm in length, the proportion of fibres decreasing with increasing fibre length. Variations in machine type did not affect the distribution of fibres with respect to fibre type, colour or length.

Transfer of Transdermally Applied Testosterone to Clothing: A Comparison of a Testosterone Patch Versus a Testosterone Gel

To assess the amount of testosterone transferred from the abdominal application sites of a transdermal testosterone patch and a transdermal testosterone gel to cotton T-shirts worn for 24 hours during each treatment. During a crossover study comparing the pharmacokinetics of a testosterone patch versus a testosterone gel in 28 hypogonadal men, subjects wore fresh cotton T-shirts for 24 hours on the seventh and fourteenth days of each treatment and during a 24-hour baseline period. At the end of each evaluation, the abdominal section of the shirt was carefully cut out, extracted in alcohol, and analyzed for testosterone by a direct radioimmunoassay. The minimum quantifiable amount of testosterone was 0.03 microg per T-shirt sample. The median amounts of extracted testosterone were 0.44 microg for the baseline samples, 25.4 microg for the average of the two patch samples, and 6,762.7 microg for the average of the two gel samples (all comparisons P < 0.0001). Significant correlations were observed between the day 7 and day 14 data for both the patch (R = 0.4982; P < 0.01) and the gel (R = 0.8383; P < 0.0001). No significant correlations were found between the baseline, patch, or gel data, or between these and any demographic or pharmacokinetic parameters. A quantitative interpretation of the findings suggests that the baseline results are consistent with the transfer of testosterone in sweat; the patch results are probably due to the transfer of a small amount of residual testosterone left on the abdominal skin from the prior day's patches; and the gel results reflect the desquamation of stratum corneum containing a portion of the abdominally applied testosterone. There are large differences in the amount of testosterone that can be transferred from the application sites of transdermal patches and gels. The latter should be covered with clothing to minimize transfer through intimate skin-to-skin contact.

Dynamic changes in sweat rates and evaporation rates through clothing during hot exposure

Dynamic changes in local sweat rates ( S w) and local evaporation rates from clothing ( E cl) have been observed during hot exposure. Four young male subjects wearing a cotton T-shirt and half shorts were exposed to 40 °C/50% for 1 h following exposure to 28 °C/50% for 30 min. Amount of water absorbed in clothing ( M sw), clothing surface temperatures ( T cl), local heat flow rates, skin temperatures, body weight, rectal temperature, S w and E cl were continuously measured. Upon exposure to the heat, decrease in heat gain to the skin was observed as opposed to increase in S w, E cl, M sw and heat gain to the clothing surface.

Effects of pressure on the skin exerted by clothing on responses of urinary catecholamines and cortisol, heart rate and nocturnal urinary melatonin in humans.

The study investigated how the pressure exerted on the skin by clothing worn while working in the daytime affected the urinary excretion of adrenaline, noradrenaline and cortisol, heart rate, and also melatonin secretion at night. Nine young women (experiment I) and seven young women (experiment II) participated. Participants wore either a 100% cotton jacket (tight clothes, TC) or a 100% cotton T-shirt (loose clothes, LC). Loose-fitting, 100% cotton tank tops and panties were worn as underwear in both the TC and the LC groups. The main results can be summarized as follows: (1) urinary excretion of adrenaline, noradrenaline and cortisol was facilitated, and the amounts of urinary excretion were significantly higher when TC were worn. Heart rate was significantly higher in the TC group; (2) nocturnal urinary melatonin excretion was significantly greater in the TC group. These results are discussed in terms of an enhancement of diurnal sympathetic nervous system activity caused by pressure on the skin produced by tight clothing.

Reduction of Ultraviolet Transmission Through Cotton T-Shirt Fabric with Low Ultraviolet Protection by Various Laundering Methods and Dyeing: Clinical Implications

Reduction of Ultraviolet Transmission Through Cotton T-Shirt Fabric with Low Ultraviolet Protection by Various Laundering Methods and Dyeing: Clinical Implications

Reduction of ultraviolet transmission through cotton t-shirt fabrics with low ultraviolet protection by various laundering methods and dyeing: Clinical implications

Background: The public has long been instructed to wear protective clothing against ultraviolet (UV) damage. Objective: Our purpose was to determine the UV protection factor (UPF) of two cotton fabrics used in the manufacture of summer T-shirts and to explore methods that could improve the UPF of these fabrics. Methods: Each of the two types of white cotton fabrics (cotton T-shirt and mercerized cotton print cloth) used in this study was divided into 4 treatment groups: (1) water-only (machine washed with water), (2) detergent-only (washed with detergent), (3) detergent-UV absorber (washed with detergent and a UV absorber), and (4) dyes (dyed fabrics). Ultraviolet transmission through the fabrics was measured with a spectrophotometer before and after laundry and dyeing treatments. Based on UV transmission through these fabrics, the UPF values were calculated. Results: Before any treatments, the mean UPFs were 4.94 for the T-shirt fabric and 3.13 for the print cloth. There was greater UVA (320-400 nm) than UVB (280-320 nm) transmission through these fabrics. After 5 washings with water alone and with detergent alone, UPF increased by 51% and 17%, respectively, for the cotton T-shirt fabric. Washing the T-shirt fabrics with detergent plus the UV-absorbing agent increased the UPF by 407% after 5 treatments. Dyeing the fabric blue or yellow increased the UPF by 544% and 212%, respectively. Similar changes in UPFs were observed for the print cloth fabric. Conclusion: The two cotton fabrics used in this study offered limited protection against UV radiation as determined by spectrophotometric analysis. Laundering with detergent and water improves UPF slightly by causing fabric shrinkage. Dyeing fabrics or adding a UV-absorbing agent during laundering substantially reduces UV transmission and increases UPF. More UVA is transmitted through the fabrics than UVB. (J Am Acad Dermatol 2001;44:767-74.)

The Effect of Laundering on the Detection of Acid Phosphatase and Spermatozoa on Cotton T-Shirts

ABSTRACTIn sexual assault cases, items submitted for forensic analysis are frequently examined for seminal fluid. The contents of a medical examination kit taken from the victim, particularly the genital swabs, are often the main source of associative DNA evidence. Depending on the circumstances, however, the examination of clothing and bedding can also be important. A standard procedure used in searching clothing is to screen for acid phosphatase and to confirm the presence of seminal fluid by examination for spermatozoa. It is frequently assumed that laundering the item in question will remove acid phosphatase and therefore testing for this enzyme is not useful. We have washed and laundered seminal stains on cotton T-shirts in a variety of ways, including dry cleaning. The cleaned fabric was screened for acid phosphatase, and the presence of spermatozoa determined. The DNA content of the cleaned stain was quantified and Short Tandem Repeat (STR) profiles were obtained using the CTT triplex. The results obtained are discussed in the context of the overall examination tactics in sexual assault cases.

PCDD/Fs in textiles — Part II: Transfer from clothing to human skin

The transfer of PCDD/Fs from contaminated textiles to the outermost layers of the skin ( stratum corneum) of human volunteers was measured. The experiments were conducted with cotton T-shirts containing high levels of hepta- and octachlorinated dibenzo- p-dioxins and dibenzofurans. The results indicated that there is little spatial variability in the transfer from the T-shirt to the skin surface (< factor 2) and also little variability among individuals (< factor 3). The percent transfer from different cotton textiles (ΣPCDD/F: 1,900 pg/g – 281,000 pg/g) to the stratum corneum was found to be similar. The transfer from a white, unbleached polyester material was more than an order of magnitude lower, indicating that the PCDD/Fs were more tightly bound to the polyester than to the cotton. It was shown that the PCDD/Fs penetrate into deeper layers of the stratum corneum during an 8 hour exposure period. However, systemic exposure and a significant contribution of this pathway to the PCDD/F body burden is only possible if the compounds are able to overcome the penetration barrier posed by the viable epidermis.

The effect of laundering on the sun protection afforded by a summer weight garment

Aim To determine what effect a period of prolonged washing and drying of a garment would have on the photoprotection afforded by the fabric of that garment.Materials and Methods Five pure cotton T-shirts from the same production lot were subjected to 36 consecutive standard washes. The fabric sun protection factors (SPFs) calculated from spectrophotometric UVR transmission data for samples taken from each garment after use were compared with those of control samples taken from the same garment prior to the study.Results There was a significant increase in fabric SPF after one wash in all shirts with no further change in 4 of 5 shirts after a further 35 washes.Conclusion The effect on fabric SPF of the first wash can account for most of the effect on fabric SPF of wash and wear in the use of a garment. The SPF rating of a pure cotton garment as new is valid for the standard lifetime of that garment.

Sun protection by a summer-weight garment: the effect of washing and wearing.

To assess the effect of use (washing and wearing) on the photoprotection provided by a cotton fabric. Twenty jersey-knit pure cotton T-shirts were worn for 4-8 hours per week and washed weekly for 10 weeks. Fabric samples taken before and after use were compared. Fabric ultraviolet protection factor (UPF) was calculated from spectrophotometric ultraviolet radiation transmission data. Changes in fabric structure and hole size were determined for samples from one T-shirt by light microscopy and image analysis. UPF increased consistently and significantly after use, from a mean of 19.0 to 40.6. A corresponding reduction in fabric hole area was seen under the light microscope and confirmed on image analysis (from 8.0% to 3.9% of total image area). UPF of pure cotton garments may improve after use, at least in the short term. The increase is mostly accounted for by reduction in fabric hole area due to shrinkage.

Effects of moisture absorption by clothing on thermal responses during intermittent exercise at 24 degrees C.

The effects of two kinds of clothing with different properties with respect to moisture absorption on thermophysiological responses and pulse rate were studied during intermittent exercise at an ambient temperature (Ta) of 24 degrees C. The two kinds of clothing ensemble tested were cotton T-shirt with short sleeves and cotton long-sleeved working dress with full-length trousers (C), and polyester T-shirt with short sleeves and polyester long-sleeved working dress with full-length trousers (P), the thermal resistances of which were nearly equal. Five women aged 21-32 years, served as subjects. The environmental conditions were 24 degrees C Ta, 50% relative humidity and 0.14 m.s-1 air velocity. The subjects, wearing either C or P, exercised for 10-min on a cycle ergometer at an intensity of 30% maximal oxygen uptake and then 10-min rest. This sequence was repeated four times. Rectal and skin temperatures at several sites, local sweating rate, pulse rate and clothing microclimates were continuously compared between C and P throughout the experiment. The major findings were firstly, rectal temperature rose significantly higher in P; secondly, pulse rate was higher in P both during exercise and rest; thirdly, clothing surface temperature on the back rose highly significantly during the fourth exercise period and then fell significantly during the fourth rest period in C; and fourthly, four out of five subjects felt wetter in P during the latter half of the experiment. These results are discussed from the viewpoint that the reduced thermal insulation due to the absorption of moisture in C accelerated dry heat loss, resulting in an inhibition of the increases in core temperature and pulse rate.