Impact of glove occlusion on cumulative skin irritation with or without hand cleanser–comparison in an experimental repeated irritation model

Background. Irritant contact dermatitis remains a substantial problem in the food processing industries. Irritants that are weak by themselves, such as glove occlusion and mild detergents, could interact to produce contact dermatitis. Objectives. To model the irritant action of an antibacterial hand cleanser and glove occlusion, with sodium lauryl sulfate (SLS) as a positive control. The effects of a pre‐exposure cream and a post‐exposure cream were also investigated. Methods. A modified repeated short‐time occlusive irritation test with 20 healthy volunteers, and application of irritants over 4 days, with pre‐exposure and post‐exposure creams and overnight glove occlusion, was performed. The changes in transepidermal water loss (TEWL) served as a measure of the irritant damage to the epidermal barrier. Results. The antibacterial cleanser and the glove occlusion separately induced only minor increases in TEWL. When combined, the two showed a tandem effect, as the TEWL increase was significantly higher, and was similar to that seen with the positive control, SLS. The pre‐exposure and post‐exposure creams alone significantly mitigated the cumulative irritation, and this effect was strongest when the two creams were combined. Conclusions. Irritant contact dermatitis may develop through the tandem effects of long‐term glove occlusion and the accumulation of barrier damage from hand washing, even when mild hand cleansers are employed.     

Estimating emollient usage in patients with eczema

Background. Atopic eczema (AE) is characterized by reduced skin hydration (SH) and impaired integrity of the skin. Proper emollient usage is an important facet of AE management and patients are encouraged to use emollients liberally. Aim. To evaluate whether the amount of emollient and skin cleanser used correlates with eczema severity, SH or transepidermal water loss (TEWL), and whether liberal usage alters disease severity, SH and TEWL. Methods. We studied SH and TEWL at three common measurement sites on the forearm (antecubital flexure, 20 mm below the antecubital flexure, mid‐forearm) and determined the SCORing Atopic Dermatitis (SCORAD) score, Nottingham Eczema Severity Score (NESS), Children’s Dermatology Life Quality Index (CDLQI) and the amount of emollient and cleanser usage over a 2‐week period in consecutive new patients seen at the paediatric skin clinic of a teaching hospital. Results. In total, 48 subjects and 19 controls were recruited. Patients with AE had significantly higher TEWL and lower SH in the studied sites. Emollient and cleanser usage was significantly higher (P = 0.001 and P = 0.041, respectively) in patients with AE than in controls. The amount of emollient usage was correlated with NESS, SCORAD, CDLQI, TEWL and mid‐forearm SH. No such correlation was found with cleanser usage. Regardless of SCORAD, prescribing 130 g/m²/week of emollient met the requirement of 95.8% of patients, and 73 g/m²/week met that of 85.4%; for the cleanser, prescribing 136 g/m²/week met the requirement of 91.7% of patients. Although skin dryness and SH were improved, there was no significant improvement in SCORAD or TEWL after 2 weeks. In terms of global acceptability of treatment, three‐quarters of patients with AE and controls rated the combination of cream and cleanser as ‘good’ or ‘very good’. Conclusions. Adequate amounts of emollient and bathing cleanser should be prescribed to patients with AE. These amounts can be conveniently estimated based on body surface area instead of the less readily available tools for disease severity, degree of SH or skin integrity. However, liberal usage of emollients and bathing cleanser alone does not seem to alter disease severity or TEWL within 2 weeks, implying that additional treatments are necessary to manage AE.     

Evaluation of an experimental patch test model for the detection of irritant skin reactions to moisturisers

Background/aims: Moisturisers are used daily by a large number of people to prevent dryness of the skin. Irritant skin reactions to moisturisers are, however, known to occur. In order to prevent such irritant reactions reliable test methods for irritancy testing of moisturisers are needed. This study was undertaken to evaluate a non‐invasive patch test model for the detection of irritant skin reactions to moisturisers. Methods: Twenty healthy volunteers were patch tested with three different moisturisers: empty chamber, sodium lauryl sulphate and a moisturizer known to be non‐irritating. Skin reactions were evaluated by visual scoring, measurement of transepidermal water loss (TEWL) by an Evaporimeter, blood flow by laser Doppler flowmetry and electrical capacitance by a Corneometer. Results: A statistically significant increase in blood flow was found 48 h after application of one of the moisturisers tested, indicating an irritant effect of the product. A statistically significant decrease in skin hydration was found for the same moisturiser after 48 h. No statistically significant differences between the moisturisers were found by visual scoring. None of the products tested had any negative effect on the skin barrier function. Conclusion: The non‐invasive patch test model was found useful for detecting irritant skin reactions to moisturisers.     

Potential for irritation increases from the wrist to the cubital fossa

The effect of site on the irritant dermatitis potential was studied in 10 subjects using the volar surface of the forearm. Erythema scoring and transepidermal water loss (TEWL) measurements were used to assess irritation at different levels on the forearm. A sodium lauryl sulphate (SLS 2 g/v%) solution was used as a standard irritant in a patch test procedure and on open tests. Both the erythema scores and measurements of the TEWL of exposed skin showed significant localization differences, and demonstrated that the same sites on the forearm should be used for irritancy tests and possibly physiological studies.     

Irritancy of the skin disinfectant n-propanol

Hand disinfection with short-chain aliphatic alcohols, so-called "rub-ins" is the method of choice for cross-infection prevention in health care environments, but their irritant potential is not well known. Skin tolerance is a major compliance factor, and a high proportion of health care workers suffer from low-grade irritant contact dermatitis. Therefore, assessment of the irritancy of the skin disinfectant n-propanol 60%, and comparative 100% and 0% solutions, was performed in the setting of experimental low-grade ICD. ICD was induced by overnight patch exposure to H2O, and to 0.3% sodium dodecyl sulfate (SDS), in 12 probands, followed by repeated open exposure to the test substances. Outcome variables were transepidermal water loss (TEWL), and skin surface capacitance. On skin sites pre-irritated by SDS, all n-propanol concentrations (100%, 60%, 0%) increased TEWL. However, a clear divergence appeared between pure n-propanol, and the lower concentrations. In contrast to pure n-propanol, n-propanol 60% and 0% had no significant effect on TEWL on H2O-pre-irritated skin sites. Capacitance of pre-irritated skin sites was increased by exposure to H2O-containing n-propanol solutions (60% and 0%). These results show a clear difference between the irritant potential of n-propanol 100% on one side, and n-propanol 60% and 0% on the other side. The level of pre-existent skin irritation is a pertinent factor in susceptibility to irritation, as the irritant potential of n-propanol 60%, the concentration used in daily practice, and n-propanol 0% (water) became significant only on detergent-irritated skin. Thus, preventive skin care may be a constructive approach in increasing tolerance of modern hand disinfection practices.     

Susceptibility to irritants: role of barrier function, skin dryness and history of atopic dermatitis

The susceptibility of the skin to various irritants was investigated with the aim of determining the role of the barrier function of the stratum corneum, skin dryness and whether a history of atopic dermatitis (AD) was a factor. The transepidermal water loss (TEWL) was measured using an evaporimeter and skin hydration using a Corneometer and by visual scoring. The group with a history of AD (n = 20) had a lower pre-exposure barrier function and a higher TEWL value following irritant exposure than the group with a history of allergic contact dermatitis (n = 18) and a control group (n = 18). Clinically dry skin was more susceptible than normal skin, though no difference was noted in the pre-exposure barrier function. The increased susceptibility to irritants in those with a past history of AD was probably due to impaired barrier function and/or the presence of a dry skin.     

Allergic contact dermatitis due to nonylphenol ethoxylate (nonoxynol-6)

The non-ionic emulsifier "nonoxynol-6" found in an industrial waterless hand cleanser induced allergic contact dermatitis on the upper extremities of a uranium mill maintenance worker. The chemical is an irritant for the rabbit. It was not shown to be a cutaneous sensitizer for the albino guinea pit using the guinea pig maximization test.     

Predictive testing of metalworking fluids: a comparison of 2 cumulative human irritation models and correlation with epidemiological data

Metalworking fluids (MWF) have been reported as being an important cause of irritant contact dermatitis in metal workers. Our purpose was to determine whether the irritancy of different MWF assessed by 2 different types of predictive human in vivo tests could be compared with epidemiological data, 3 water-based MWF were tested in the same panel of subjects. Reactions were assessed by a visual score (VS), evaporimetry to evaluate the transepidermal water loss (TEWL) and chromametry to quantify erythema. Test 1 : MWF were applied with Finn Chambers on the volunteers' mid-back, removed after 1 day of exposure, and reapplied for a further 2 days Test 2 : Cumulative irritant contact dermatitis was induced using a repetitive irritation test for 2 weeks (omitting weekends) for 6 h per day. We observed an increase in VS, TEWL, and erythema for all MWF, with the same irritancy ranking in both test models. Differentiation of the substances was better in the D1/D3 test. The experimental results partially correlated with the epidemiological data, Considering the shorter application time and the better discrimination of irritancy, we prefer the D1/D3 model as a predictive test of MWF irritancy. Our results might aid development of a Standardized test to reduce cumulative skin irritation in metal workers.     

Skin cleansers: three test protocols for the assessment of irritancy ranking

In this article, the results of 3 studies on 2 hand cleansers (products A and B) are analysed. Three different test models (the patch test, the forearm wash test and the use test) are used to obtain information on the skin irritancy of these 2 products. Test reactivity was assessed by clinical scores and bioengineering methods such as corneometry for skin moisture, transepidermal water loss measurements for barrier function and chromametry for erythema. A correlating trend of product A being more aggressive than product B could be confirmed in all 3 studies and was statistically significant in the patch-testing series. Distinction of the results was dependent on the test protocol employed. Models for testing cleansing preparations should be chosen carefully, depending on the hypothesis to be evaluated.     

Corneometric, sebumetric and TEWL measurements following the cleaning of atopic skin with a urea emulsion versus a detergent cleanser

A non-detergent urea emulsion cleanser and a detergent cleanser with added moisturizers were compared for their effects on stratum corneum moisture, surface lipids and transepidermal water loss (TEWL) of atopic skin. Following a single wash with either cleanser, low corneometry and sebumetry values increased and elevated TEWL values decreased. Over the course of more than 6 h, all induced changes gradually returned to their starting points. In all instances, the changes induced by the urea emulsion lasted significantly longer than those caused by the detergent cleanser. The sebumetry increase after a wash with the lipid-free detergent cleanser indicated that this method recognized not only true lipids but also the lipid-derived and skin lipid-depleting detergents. The transient TEWL normalization with either cleanser could not be attributed to a passing barrier restoration nor to an occlusion. It is speculated that the TEWL changes were related to stratum corneum water binding capacity.     

A double‐blind,randomized study to assess the effectiveness of different moisturizers in preventing dermatitis induced by hand washing to simulate healthcare use

Background Healthcare‐associated infection is an important worldwide problem that could be reduced by better hand hygiene practice. However, irritant contact dermatitis of the hands as a result of repeated hand washing is a potential complication that may be preventable by the regular use of an emollient. Objectives To assess the effect of moisturizer application after repeated hand washing (15 times daily) vs. soap alone. Methods In a double‐blind, randomized study, the effect of five different moisturizers on skin barrier function was determined by assessment after repeated hand washing over a 2‐week period in healthy adult volunteers. Assessments of transepidermal water loss (TEWL), epidermal hydration and a visual assessment using the Hand Eczema Severity Index (HECSI) were made at days 0, 7 and 14. Results In total, 132 patients were enrolled into the study. A statistically significant worsening of the clinical condition of the skin as measured by HECSI was seen from baseline to day 14 (P = 0·003) in those subjects repeatedly washing their hands with soap without subsequent application of moisturizer. No change was seen in the groups using moisturizer. Subclinical assessment of epidermal hydration as a measure of skin barrier function showed significant increases from baseline to day 14 after the use of three of the five moisturizing products (P = 0·041, 0·001 and 0·009). Three of the five moisturizers tested led to a statistically significant decrease in TEWL at day 7 of repeated hand washing. This effect was sustained for one moisturizing product at day 14 of hand washing (P = 0·044). Conclusions These results support the view that the regular application of moisturizers to normal skin offers a protective effect against repeated exposure to irritants, with no evidence of a reduction in barrier efficiency allowing the easier permeation of irritant substances into the skin as has been suggested by other studies. Regular use of emollient in the healthcare environment may prevent the development of dermatitis.     

Post-application occlusion substantially increases the irritant response of the skin to repeated short-term sodium lauryl sulfate (SLS) exposure

Occlusion often, but not always, enhances percutaneous absorption and thus may facilitate skin irritation. Quantitative data about the impact occlusivity may have on minimal irritant stimuli to which the skin is exposed in daily life, and which may lead to chronic irritant contact dermatitis, are however lacking. Irritant stimuli were administered by repeated application of sodium lauryl sulfate (SLS) in an open application procedure. After the open exposure, the skin was either left open or occluded with plastic. Skin irritancy was assessed by means of visual grading and by transepidermal water loss (TEWL) measurements. Post-exposure occlusive treatment markedly enhanced the irritant response. 5 consecutive daily applications produced more irritation, with or without occlusion, than alternate day application. Occlusion may be a relevant factor in the development of irritant contact dermatitis from certain chemicals.     

Comparison of human back versus arm skin region for its suitability to test weak irritants

Background/aims: Large-scale comparative screening of der-matological and cosmetic products require non-invasive bioengineering methods which give reproducible results that can be statistically analyzed. To determine the most suitable test region for testing irritating substances, the response of the skin to the weak irritant sodium lauryl sulphate (SLS) was measured on standardized locations on the forearm and back. Furthermore, using 3 bioengineering methods, we aimed to establish the most sensitive method to measure skin response to SLS.
Methods: The baseline measurements of transepidermal water loss (TEWL), cutaneous blood flow (CBF) and skin colour a*-value were performed at 6 standardized locations on the volar forearms and at 12 locations on the back on 2 consecutive days, day 1 and 2, in 9 healthy volunteers. On day 2, 9 out of the 18 sites were exposed to 0.5% SLS by occlusive 24-h patches and the skin response was evaluated on days 3 and 4.
Results: For TEWL, CBF and a*-value, no significant regional variations were found within individuals at any time on the arm locations and on the back locations. However, significant inter-individual variation was found. At the back on day 4, a slightly higher skin response to SLS was found compared to that found on the forearms as measured by TEWL and the a*-value. Of the 3 bioengineering methods used, TEWL was the most sensitive method to detect cutaneous response to the weak irritant used. TEWL measurements on days 1 and 2 performed at the 6 standardized locations on the volar forearms inside and outside a specially constructed air convection protection box, showed no relevant differences in measured TEWL values.
Conclusion: Both the forearms and the back were found to be suitable sites for irritancy testing. Since considerable differences in mean reactivity between subjects have been observed the use of large numbers of subjects in predictive irritant patch testing is required.     

Prevalence of potential contact allergens in best-selling baby cleansers

Many baby cleansers are promoted as hypoallergic products; however, these claims are not typically validated. This study assessed the 50 best-selling baby cleansers from online retailer Amazon for potential allergens. We found that the presence of most marketing claims, including “hypoallergenic” or “allergy-tested,” did not correlate with the number of potential allergens in a cleanser. Furthermore, the total number of marketing claims of a cleanser was positively correlated with the number of allergens, highlighting the discordance between marketing claims and allergen content in baby cleansers.     

The effect of 3 moisturisers on skin surface hydration

Background/aims: The hydrating properties of three moisturising preparations, commonly recommended for the treatment of dry skin, were compared by utilising non-invasive measuring methods.
Methods: The preparations were Decubal®/Abitima® cream, Dumex Ltd; pH5-Eucerin® ointment, Beiersdorf; and Essex® cream, Schering Plough. Skicon-200® and a Corneometer CM 420® were used for assessment of skin hydration. Readings of the transepidermal water loss (TEWL) and skin temperature were also taken. The study was conducted in 2 parts, each with 12 women. The preparations were applied to a designated area on the forearms 2× a day for 7 days; the 4th, untreated, area served as control. Readings were taken before the start of treatment and every morning during the treatment period and the following week.
Results: Both electrical measuring methods showed that hydration of the stratum corneum increased after a few days of treatment, especially after the application of Decubal®/Abitima®. TEWL was not affected by any of the treatments.
Conclusions: The two electrical methods ranked the products consistently, i.e. Decubal®/Abitima® >pH5-Eucerin® >Essex®. Conductance (Skicon-200) was more discriminative than capacitance (Corneometer CM420). However, these methods are not water specific. TEWL was not affected by the treatments.     

Friction, capacitance and transepidermal water loss (TEWL) in dry atopic and normal skin

The biophysical properties of non-eczematous skin at three locations in atopics and non-atopics were characterized using non-invasive physical methods. Skin friction was measured with a newly developed sliding friction instrument, the degree of hydration with a capacitance meter (Corneometer CM 820), and the transepidermal water loss (TEWL) was determined using an Evaporimeter EP1. The areas examined (dorsum of the hand, volar forearm and lower back) showed lower values of friction and capacitance in the atopic patients than did corresponding sites in the normal controls. In most areas a significant correlation between friction and capacitance was found. The TEWL was increased in atopic skin, but TEWL seems to correlate neither to friction nor to capacitance.     

Effect of glove occlusion on human skin (II)

Gloves are indispensable in many occupations. Irritant skin reactions from gloves have, however, been reported. In the present study, the effect of long-term glove occlusion on normal skin (6 h/day for 14 days) was studied and, in addition, the effect of a cotton glove worn under the occlusive glove was also studied. 2 studies were performed (studies A and B). Study A: 19 volunteers wore an occlusive glove on normal skin 6 h/day for 14 days. They wore the glove on one hand only, while the other hand served as control. Study B: 18 volunteers wore occlusive gloves on both hands on normal skin. A cotton glove was worn under the occlusive glove on either the left or the right hand. Skin barrier function was evaluated by measurement of transepidermal water loss (TEWL) (Evaporimeter) skin hydration by electrical capacitance (Corneometer) and inflammation by erythema index (Derma-Spectrometer). The gloves used were hypoallergenic non-latex gloves. Results Study A: glove occlusion on normal skin 6 h/day for 14 days had a significant negative effect on skin barrier function, as measured by TEWL. Study B: the negative effect on skin barrier function from occlusive gloves was prevented by the use of a cotton glove. It is concluded that gloves may be a substantial factor in the pathogenesis of cumulative irritant contact dermatitis, and that recommendations as to their use are important.     

Cutting oil dermatitis on guinea pig skin

The effect of repeated exposure of cutting oil on 8 guinea pigs' skin was evaluated by visual scoring for erythema and skin water vapour loss (SVL) measurement over a 6-week period. The visual scores (measuring severity of erythema) and SVL values were significantly higher on skin treated with cutting oils (positive control) compared to untreated skin (negative control) throughout the study period. The scores and SVL values returned to near-baseline values when cutting oil application was stopped. In addition, the effect of 2 "after-work" emollient creams on 8 guinea pigs' skin repeatedly treated with a cutting oil was assessed by similar methods. The visual scores and SVL values of guinea pig skin that was repeatedly treated with the cutting oil and moisturized with "after-work" emollient creams, were significantly higher than negative and positive control guinea pig skin. It appeared that the 2 "after-work" emollient creams do not alleviate the irritant effect of the cutting oil on guinea pig skin. They appeared to aggravate the irritant effect of the cutting oil.     

Human irritant response to qualities and concentrations of cocoamidopropylbetaines: a possible model of paradoxical irritant response

Cocoamidopropylbetaines are surfactants frequently used in cosmetics. We have evaluated the irritant capacity of 3 different qualities of cocoamidopropylbetaine, using the following method: patch tests have been carried out with 5 different dilutions in 67 patients and the results read at 2 days by noninvasive methods (direct visualization, transepidermal water loss (TEWL), laser Doppler flowmetry (LDF)). The results with the 3 methods were concordant. However, the results with the different concentrations were paradoxical, as irritancy did not increase at higher concentrations. We have tried to explain this by the fact that these substances contain by-products (free amidoamine and sodium monochloroacetate), the concentrations tested all being above the critical micelle concentration and therefore containing both micelles and monomer. Finally, we believe that noninvasive methods such as TEWL and LDF could be of great use in the evaluation of irritant contact dermatitis.