Debunking the Myth of Wool Allergy: Reviewing the Evidence for Immune and Non-immune Cutaneous Reactions.

Although wool is commonly believed to cause irritant (non-immune) and hypersensitivity (immune) cutaneous reactions, the evidence basis for this belief and its validity for modern garments have not been critically examined. Publications from the last 100 years, using MEDLINE and Google Scholar, were analysed for evidence that wool causes cutaneous reactions, both immune-mediated (atopic dermatitis exacerbation, contact urticaria, allergic contact dermatitis) and non-immune-mediated (irritant contact dermatitis, itch). Secondary aims of this paper were to examine evidence that lanolin and textile-processing additives (formaldehyde, chromium) cause cutaneous reactions in the context of modern wool-processing techniques. Current evidence does not suggest that wool-fibre is a cutaneous allergen. Furthermore, contact allergy from lanolin, chromium and formaldehyde is highly unlikely with modern wool garments. Cutaneous irritation from wool relates to high fibre diameters (≥ 30-32 µm). Superfine and ultrafine Merino wool do not activate sufficient c-fibres to cause itch, are well tolerated and may benefit eczema management.

Pulmonary function parameters in workers of woolen industry.

There is an increase in proportion of workers suffering from occupational diseases. In occupational respiratory diseases, pulmonary function tests are the most important and widely used diagnostic tool. Limited studies have been conducted to evaluate the effect of wool dust on pulmonary function parameters. Hence, the present study was undertaken to evaluate the pulmonary function parameters in workers of woolen industry. This study was done on 150 subjects of either gender who were divided into two groups of 75 each. Group I comprised of healthy subjects who served as controls and group II included workers of woolen industry. The values of lung function parameters i.e. volumes and flow rates in these workers were found to be lower than the healthy controls. The significant reduction in percentage predicted values of FEV1 (82 vs 59), FVC (79 vs 63) and MVV (77 vs 64) in workers as compared to healthy controls indicates obstructive pattern of respiratory abnormality. In male workers, percentage predicted FEV1% was significantly lower. The values of all other parameters were lower in female workers. There was a significant decrease in FEV and FVC with increase in age in group I and this negative correlation was statistically significant. The decrease in respiratory volumes and flow rates was more with increase in duration of exposure to wool dust. It can be concluded that wool dust present in environment of woolen industry affected the pulmonary function parameters of the workers leading to obstructive pattern of respiratory changes.

The effect of two sock fabrics on perception and physiological parameters associated with blister incidence: a field study.

The goal of the present study was to investigate differences in perception and skin hydration at the foot of two sock fabrics with distinct moisture properties in a realistic military setting. Thirty-seven military recruits wore two different socks (PP: 99.6% polypropylene and 0.4% elastane, and BLEND: 50% Merino-wool, 33% polypropylene, and 17% polyamide), one on each foot. Measurements were carried out after a daily 6.5-km march on 4 days. Each participant rated temperature, dampness, friction, and comfort for each foot. On a daily selection of participants, skin hydration was measured on three sites of both feet using a corneometer, and moisture content of the socks was determined. BLEND was rated to be cooler, less damp, and more comfortable (P < 0.05). Two out of three skin sites were drier for BLEND than PP (P < 0.05). Moreover, BLEND stored 2.9 ± 0.3 times more moisture compared to PP. Thus, under the present conditions, socks such as BLEND are to be preferred over polypropylene socks.

The effect of two sock fabrics on physiological parameters associated with blister incidence: a laboratory study.

The goal of the present study was to investigate physiological effects, mainly at the level of the foot, of two sock fabrics with distinct moisture properties. Twelve participants wore two different socks, one on each foot. The following two sock types were used: PP: 99.6% polypropylene and 0.4% elastane and BLEND: 50% Merino wool, 33% polypropylene, and 17% polyamide. The participants walked three times on a treadmill at 5 km h(-1), with no gradient for the first and third phase and a 10% upward inclination for the second walking phase. The microclimate temperature between the boot and foot was measured during walking. Preceding and following the walking phases, additional measurements were carried out at the level of the foot, i.e. skin temperature and skin hydration on three locations and skin friction between the posterior surface of the calcaneus and a glass plate. In addition, the moisture absorption of boots and socks was determined. Differences between the sock fabrics were found for weight gain and microclimate temperature: (i) PP tended to hold less water compared to BLEND, (ii) the boot's microclimate temperature resulted in larger values for BLEND measured at the dorsal surface at the level of the third metatarsal, and (iii) warmer microclimates of the boot were measured for PP compared to BLEND at the distal anterior end of the tibia. The established differences in moisture behavior of both socks did not result in detectable differences in parameters measured on the skin of the foot.

Contact sensitization in patients with lower extremity dermatitis in the South Moravian region, Czech Republic.

OBJECTIVES: The aim of the study was to determine the frequency of contact sensitization in patients with lower extremity dermatitis. METHODS: Between the years 2001 and 2007, the authors investigated 462 patients (mean age 49.1 years, 196 men and 266 women) with the eczema/dermatitis localized on their lower extremities, including feet. The patients were investigated with epicutaneous tests of the European Standard Series and also with other special patch tests. RESULTS: The most frequent allergens were balsam of Peru, 44/462 (9.5%); wool alcohols, 41/462 (8.9%); nickel sulphate, 39/462 (8.4%); propolis, 35/462 (7.6%); fragrance mix, 34 (7.4%) and colophony, 29/462 (6.3%). CONCLUSIONS: In patients with lower extremity dermatitis the frequency of contact sensitization is still high, and therefore investigation with epicutaneous tests should belong to the routine dermatological diagnostic procedure in these patients.

Cytotoxicity study of high temperature wool (HT wool) by cell magnetometric evaluation.

OBJECTIVES: We performed a cytotoxicity study by cell magnetometry, measured lactate dehydrogenase (LDH) activity by enzyme assay, detected DNA ladder formation, and performed morphological examination by electron microscopy in order to evaluate the safety of high temperature wool (HT wool), an asbestos substitute, using long and short chrysotile fibers (CF) as positive controls and phosphate buffered saline (PBS) as a negative control. METHODS: Alveolar macrophages were isolated from male Fisher rats. Following the addition of iron oxide particles (Fe(3)O(4)) to macrophages, HT wool, long or short CF was added. Then, the remanence strength was measured for 20 min after magnetization by an external field. Percent LDH release was calculated after determining LDH activity. DNA was detected using an apoptosis detection kit. Morphological observation was performed by taking electron micrographs of macrophages in the groups treated with HT wool and long- and short-CF. RESULTS: Rapid relaxation, an indicator of decay of cytotoxicity, was observed by cell magnetometry immediately after magnetization was ended in the groups treated with HT wool and PBS, showing that HT wool causes no harmful effect on the cytoskeleton. The CF-treated groups had higher LDH activity than the PBS- and HT wool-treated groups. No fragmentation of DNA was observed in any group. In morphological observation, cytotoxicity in macrophages was lower in the HT wool-treated groups than in the CF-treated groups. CONCLUSIONS: The results suggest that HT wool has no cytotoxicity, as evaluated by cell magnetometry, enzyme assay, DNA ladder detection and morphological examination.

Toxicological responses in SW mice exposed to inhaled pyrolysates of polymer/tobacco mixtures and blended tobacco.

Modern cigarette manufacturing is highly automated and produces millions of cigarettes per day. The potential for small inclusions of non-cigarette materials such as wood, cardboard packaging, plastic, and other materials exists as a result of bulk handling and high-speed processing of tobacco. Many non-tobacco inclusions such as wood, paper, and cardboard would be expected to yield similar pyrolysis products as a burning cigarette. The aircraft industry has developed an extensive literature on the pyrolysis products of plastics, however, that have been reported to yield toxic by-products upon burning, by-products that have been lethal in animals and humans upon acute exposure under some exposure conditions. Some of these smoke constituents have also been reported in cigarette smoke. Five synthetic polymers, nylon 6, acrylonitrile-butadiene-styrene (ABS), nylon 12, nylon 6,6, and acrylonitrile-butadiene (AB), and the natural polymer wool were evaluated by adding them to tobacco at a 3, 10, and 30% inclusion level and then pyrolyzing the mixture. The validated smoke generation and exposure system have been described previously. We used the DIN 53-436 tube furnace and nose-only exposure chamber in combination to conduct exposures in Swiss-Webster mice. Potentially useful biological endpoints for predicting hazards in humans included sensory irritation and pulmonary irritation, respiratory function, clinical signs, body weights, bronchoalveolar lavage (BAL) fluid analysis, carboxyhemoglogin, blood cyanide concentrations, and histopathology of the respiratory tract. Chemical analysis of selected smoke constituents in the test atmosphere was also performed in order to compare the toxicological responses with exposure to the test atmospheres. Under the conditions of these studies, biological responses considered relevant and useful for prediction of effects in humans were found for sensory irritation, body weights, BAL fluid analysis, and histopathology of the nose. There was a marked sensory irritation response that recovered slowly for some polymers. Sustained body weight depression, lesions of the respiratory epithelium of the nose, and morphological changes in pulmonary alveolar macrophages (PAM) were observed after exposure to some polymer/tobacco pyrolysates. These responses were increased compared to exposure to tobacco pyrolysate alone. No moribundity or mortality occurred during the study. The data suggest that polymeric inclusions pose a minimal additional toxicologic hazard in humans.

Lanolin allergy: history, epidemiology, responsible allergens, and management.

Allergy to lanolin has been recognized by dermatologists for decades. This review summarizes the history, epidemiology, and allergenicity of lanolin and its derivatives. "The lanolin paradox" and the safety of pharmaceutical-grade lanolin products are also discussed.

Study of skin-fabric interactions of relevance to decubitus: friction and contact-pressure measurements.

BACKGROUND/PURPOSE: Prolonged pressure as well as friction and shear forces at the skin-textile interface are decisive physical parameters in the development of decubitus. The present article describes the contact phenomena at the skin-textile interface and the development of a purpose-built textile friction analyser (TFA) for the tribological assessment of skin-fabric interactions, in connection with decubitus prevention. METHODS: Interface pressure distributions were recorded in the pelvic and femoral regions between supine persons and a foam mattress. Fabrics made of various natural and synthetic yarns were investigated using the TFA. A vertical load of 7.7 kPa was applied to the swatches, simulating high interface pressures at the skin-fabric interface and clinical conditions of bedridden persons. Fabrics were rubbed in reciprocating motions against a validated skin-simulating material to determine static as well as dynamic friction coefficients (COFs). RESULTS: Maximum contact pressures ranged from 5.2 to 7.7 kPa (39-58 mmHg) and exceeded the capillary closure pressure (32 mmHg) in all investigated bedding positions. For both COFs, a factor of 2.5 was found between the samples with the lowest and highest values. Our results were in a similar range to COFs found in measurements on human skin in vivo. The results showed that our test method can detect differences of 0.01 in friction coefficients. CONCLUSION: TFA measurements allow the objective and reliable study of the tribology of the skin-textile biointerface and will be used to develop medical textiles with improved performance and greater efficacy for decubitus prevention.

Calibration study on subchronic inhalation toxicity of man-made vitreous fibers in rats.

This 3-mo inhalation study investigated the biological effects of a special-purpose glass microfiber (E-glass microfiber), the stone wool fiber MMVF21, and a new high-temperature application fiber (calcium-magnesium-silicate fiber, CMS) in Wistar rats. Rats were exposed 6 h/day, 5 days/wk for 3 mo to fiber aerosol concentrations of approximately 15, 50, and 150 fibers/ml (fiber length >20 microm) for E-glass microfiber and MMVF21. For the CMS fiber only the highest exposure concentration was used. During a 3-mo postexposure period, recovery effects were studied. In the highest exposure concentration groups, gravimetric concentrations were 17.2 mg/m3 for E-glass microfiber, 37 mg/m3 for MMVF21, and 49.5 mg/m3 for the CMS fiber. After 3 mo of exposure, lung retention of fibers longer than 20 micro m per lung was 17 x 10(6) for E-glass microfiber, 5.7 x 10(6) for MMVF21, and 0.88 x 10(6) for CMS. After 3 mo of recovery the concentration of the long fiber fraction was decreased to 38.4%, 63.9%, and 3.0% compared to original lung burden for the E-glass microfiber, MMVF21, and CMS, respectively. Biological effects measured included inflammatory and proliferative potential, histopathology lesions, and the persistence of these effects over a recovery period of 3 mo. Generally, observed effects were higher for E-glass microfiber when compared to MMVF21. The following clear dose-dependent effects on E-glass microfiber and MMVF21 exposure were observed as main findings of the study: increase in lung weight, in measured biochemical parameters and polymorphonuclear leukocytes (PMN) in the bronchoalveolar lavage fluid (BALF), in cell proliferation (BrdU-response) of terminal bronchiolar epithelium, and in interstitial fibrosis. The values observed in the proliferation assay on the carcinogenic E-glass microfiber indicate that this assay has an important predictive value with regards to potential carcinogenicity. Surprisingly, for the biosoluble CMS fiber, fibrogenic potential was detected in this study. The results of the CMS exposure group indicate that effects may be dominated by the presence of nonfibrous particles and that fibrosis may not be a predictor of carcinogenic activity of fiber samples, if the fiber preparation contains a significant fraction of nonfibrous particles. In summary, this study demonstrates the importance of fiber dust contamination by granular components. For future subchronic studies a longer posttreatment observation period would be advisable.

Occupational rhinoconjunctivitis and asthma in a wool worker caused by Dermestidae spp.

BACKGROUND: The family Dermestidae belongs to the order Coleoptera. Occupational allergy has been described in museum personnel. A 31-year-old male wool worker presenting rhinoconjunctivitis and asthma episodes probably linked to exposure to Dermestidae-infected wool was investigated. METHODS: Extracts prepared either from insect bodies or from dust from parasitized wool were used for skin prick testing (SPT), conjunctival and bronchial provocation tests and in vitro determinations. RESULTS: SPT and provocation tests were positive to both extracts. PEFR measurement demonstrated the association between the patient's symptoms and occupational exposure to Dermestidae. Specific IgE to both extracts was detected and immunoblotting revealed several protein bands from 5 to 200 kDa that were reactive to IgE from the patient's serum. CONCLUSIONS: Dermestidae exposure in wool workers when handling parasitized wool can be a cause of IgE-mediated rhinoconjunctivitis and asthma.

Respiratory symptoms and pulmonary function in a group of women weavers in South Africa.

Respiratory symptoms and ventilatory capacity were studied in 97 women carpet weavers in a hand-made carpet weaving industry in Umtata, Transkei, South Africa. The controls were from a bottling plant in the same city. Both groups were Black Africans from the Xhosa-speaking population. The population we studied were non-smokers and there was no significant difference in age, race or height between the groups. The exposed weavers had significantly lower forced expiratory indices than the control group. Mean forced expiratory volume in 1 second (FEV1), forced mid-expiratory flow (FEF 25-75%), forced expiratory flow between 200 ml and 1200 ml of forced vital capacity (FEF 200-1200), and peak expiratory flow (PEF) were: 26.0%, 39.0%, 36.4% and 28.5% lower respectively in the exposed group compared with the controls. Mean forced vital capacity (FVC) and forced expiratory ratio (FEV1/FVC x 100) were 22.0% and 6.6% lower respectively in the exposed group compared with the controls. The percentage predicted (%pred) values of FVC, FEV1, FEV1/FVC ratio, FEF 25-75%, FEF 200-1200, and PEF in the exposed group were 82.9%, 77.1%, 95.6%, 64.6%, 72.2% and 82.8%, respectively. The prevalence of FEV1/FVC ratio less than 70% in the exposed group was 37.2%, while in the controls it was 12%. The exposed group reported a significantly higher prevalence of respiratory symptoms compared to the control. The prevalence of nasal symptoms and cough was 62.8% and 58.1%, respectively in the weavers. Weavers who reported cough, breathlessness, and wheezing had significantly (p < 0.01) lower pulmonary function than those who did not report these symptoms. The present study demonstrates that the continual exposure to dust in weavers in this industry is associated with significantly lower pulmonary function, higher prevalence of respiratory symptoms, and weavers show signs of airway obstruction compared to workers not exposed to this type of dust. Women in the weaving industry have a significant occupationally related respiratory impairment.

Immunological reactions and respiratory function in wool textile workers.

Immunological status and respiratory function were studied in a group of 64 wool textile workers (52 women and 12 men). A group of 46 workers not exposed to wool dust served as a control for the respiratory symptoms and immunologic testing. Skin testing was performed with different wool allergens (domestic and Australian) as well as with common allergens. Ventilatory capacity was measured in wool workers on Mondays before and after the work shift. The prevalence of positive skin tests to all allergens was higher in wool than in control workers, although the difference was statistically significant only for washed domestic wool (wool workers: 42.2%; control workers: 19.6%; p < 0.05). Increased serum IgE levels were more frequent in wool (26.6%) than in control workers (3.1%) (p < 0.01). In wool textile workers there was a high prevalence of acute and chronic respiratory symptoms. Significant across-shift reductions in ventilatory capacity tests, as well as abnormal baseline lung function, were recorded in wool textile workers. Individual data demonstrated that many of the wool workers had FEF25 lower than 70% of predicted. In general, the prevalence of symptoms and the lung function abnormalities did not correlate with the results of specific (wool) skin tests. Our data indicate that exposure to wool dust in some workers may be associated with the development of acute and chronic respiratory symptoms and impairment of lung function. Immunologic abnormalities, although frequent in this group, do not appear to be associated with the severity of these changes.

Textile dermatitis: an update. (I). Resins, additives and fibers.

Cases of textile-related dermatitis reported in the medical literature after the mid-1980s are reviewed. Part I focuses on cases in which textile resins, fiber additives, or fibers were the causal agent. Studies which provide insight into understanding fabric-induced prickle and itch are included.

Pharmacologic characterization of wool dust extract in isolated guinea pig trachea.

Wool mill workers develop respiratory symptoms and lung function abnormalities associated with their work in the textile industry. As in other workplaces, which process organic materials, the dust generated in the manufacture of wool has been implicated as a cause of these respiratory problems. Pharmacologic studies of wool dust extract were performed in vitro on guinea pig tracheal (GPT) segments. A wool dust extract (WDE) was prepared from material collected from a mill previously surveyed. When the standardized WDE solution was added to an organ bath in increments of 10, 30, 100, 300, and 1000 microliters it caused a consistent, dose-dependent constriction of GPT. Pretreatment of guinea pig tracheas, prior to WDE challenge, with atropine (10(-6) M), pyrilamine (10(-6) M), indomethacin (10(-6) M), verapamil (10(-6) M), TMBS (10(-6) M), BW755C (10(-6) M) and LY171883 (10(-6) M) was studied in order to evaluate receptor-dependent and -independent characteristics of WDE-induced constriction. WDE-induced bronchoconstriction was partially inhibited by the antihistamine pyrilamine. Atropine and leukotriene inhibitors (LY171883 and BW755C) were not found to have a significant protective effect on WDE-induced constriction. Both TMBS and verapamil (intra- and extracellular calcium blocking agent) suppressed the effect of wool dust extract in the range tested. These findings suggest that in this model, WDE-induced airway constriction is only partly attributable to common mediators of bronchoconstriction (e.g., histamine). The airway effects of WDE may be modulated by calcium channel blocking agents.