Hand eczema and atopic dermatitis in adolescents: a prospective cohort study from the BAMSE project

BACKGROUND

There is a well-known association between atopic dermatitis (AD) and hand eczema but less is known about how age at onset, persistence and severity of AD influence the risk of developing hand eczema.

OBJECTIVES

To examine the role of AD in the occurrence of hand eczema in adolescence. In addition, associations between asthma and rhinoconjunctivitis, sensitization to common airborne and food allergens, and hand eczema were studied.

METHODS

From the population-based birth cohort BAMSE, 2927 adolescents who had been followed up repeatedly concerning allergy-related disease were included. Questionnaires identified adolescents with hand eczema at 16 years, and their blood was analysed for specific IgE.

RESULTS

A total of 152 (5·2%) adolescents had hand eczema at the age of 16 years. Many of these adolescents had a history of AD (n = 111; 73·0%) and asthma and/or rhinitis (n = 83; 54·6%), respectively. Children with AD (aged 0-16 years) had more than threefold increased odds ratios (OR) for having hand eczema; those with persistent or severe AD had a crude OR of 6·1 [95% confidence interval (CI) 4·0-9·1] and 5·3 (95% CI 2·9-9·6), respectively.

CONCLUSIONS

We confirm a strong association between AD during childhood and hand eczema in adolescence. Children with persistent or more severe AD are at greater risk of developing hand eczema. Asthma and/or rhinoconjunctivitis, positive specific IgE or age at onset of AD are not associated with hand eczema in adolescence.

Is skin exposure to water mainly occupational or nonoccupational? A population-based study

BACKGROUND

Skin exposure to water is considered to contribute to hand eczema. Knowledge about total water exposure during a day is scanty.

OBJECTIVES

To investigate self-reported water exposure at work as well as throughout the day.

METHODS

Skin exposure to water was assessed from two questionnaire-based health surveys: the nationwide Environmental Health Survey 2007 (EHS), which enquired about water exposure throughout the day, and the Stockholm Public Health Survey 2006 (PHS), which probed water exposure at work. Answers from 19,667 individuals (EHS) and 18,318 individuals (PHS) were available for analysis.

RESULTS

In total, 22% of respondents (women 30%, men 12%) reported skin exposure to water more than 20 times during an entire day (EHS) compared with 6% (women 8%, men 4%) at work (PHS). In a univariate analysis, using a merged file comprising data from the EHS and the PHS, water exposure more than 20 times a day was more common in the EHS (prevalence proportion ratio 3·570, 95% confidence interval 3·353-3·802). In multivariate models the variables studied did not fulfil the criteria for being confounders. Water exposure at work declined with increasing age in both women and men (P < 0·0001) as did water exposure during the entire day in men (P < 0·0001). However, women were equally exposed during the entire day across age groups (P = 0·205).

CONCLUSIONS

High water exposure over the entire day was found to be considerably more frequent than exposure at work. Thus, a significant proportion of water exposure seems to occur outside work. This should be considered in prevention of hand eczema and when counselling patients with hand eczema in clinical practice.

Hand eczema and quality of life: a population-based study

BACKGROUND

Hand eczema is a common disease in the population and is of interest from a public health perspective. Health-related quality of life (HRQoL) is increasingly being measured in dermatology.

OBJECTIVES

To investigate HRQoL in relation to hand eczema in the general population.

METHODS

In the Public Health Survey of Stockholm County Council 2006, a questionnaire was sent to 57 009 randomly selected individuals aged 18-84 years. The response rate among persons of working age (18-64 years) was 58%. The questionnaire included a validated question concerning hand eczema and a generic instrument for measurement of HRQoL, the EQ-5D.

RESULTS

The proportion of individuals reporting problems was significantly larger among those with than without hand eczema in all five dimensions of the EQ-5D. Gender differences were found in some age subgroups. The EQ-5D index was lower for individuals with hand eczema than for those without, and on the same level as for psoriasis and asthma. Beta regression showed that the strongest confounding factors were low back pain, depression and hay fever/asthma.

CONCLUSIONS

HRQoL was negatively affected in individuals with hand eczema irrespective of age. With the EQ-5D instrument it is also possible to detect certain gender differences. The EQ-5D index for hand eczema was of the same size as for psoriasis and asthma, all common diseases with an impact on public health. It is of importance to acknowledge the influence of hand eczema on daily life, in order to give the patients good care.

Occupational skin exposure to water: a population-based study

BACKGROUND

Occupational exposure to skin irritants, in particular to water, is an important risk factor for hand eczema.

OBJECTIVES

To assess occupational skin exposure to water in the general population.

METHODS

As part of a public health survey in Stockholm, Sweden, 18,267 gainfully employed individuals aged 18-64 years completed a questionnaire with previously validated questions regarding occupational skin exposure to water.

RESULTS

Altogether 16% reported exposure to water for (1/2) h or more a day, and 13% reported exposure to water more than 10 times a day. Furthermore, 7% reported water exposure of more than 2 h and 6% of more than 20 times a day. Women reported more water exposure than men and many female-dominated occupations were seen to comprise water exposure. Women were also more exposed than men within the same jobs. Young adults were more exposed than older. A total of 18% were employed in high-risk occupations for hand eczema. Fifty-nine per cent of individuals employed in high-risk occupations reported water exposure at work, compared with 11% in low-risk occupations.

CONCLUSIONS

A total of 20% of the population of working age acknowledged occupational skin exposure to water, which was found to be more common in young adults and women. Using job title as a proxy for water exposure gives an underestimation due to misclassification. In assessing occupational skin exposure to water, both exposure time and frequency should be considered.

Remembering childhood atopic dermatitis as an adult: factors that influence recollection

BACKGROUND

Atopic dermatitis (AD) is common in the population, and studies have shown that the disease is on the increase. Studies based on hospital records reflect selected populations and may miss less severe cases of AD, and the use of self-reported questionnaires has the drawback of recall bias.

OBJECTIVES

To investigate some possible factors influencing recall bias when questionnaires are used to establish the prevalence of childhood eczema in an adult population.

METHODS

A questionnaire regarding past and present eczema was sent to 557 cases (with signs suggesting the diagnosis AD) and 554 matched controls (subjects lacking signs of AD) born during 1960-1969 and identified in school health medical records. Cases and controls were aged 31-42 years at the time of the study and 70.5% returned the questionnaire.

RESULTS

Of 403 cases, 29% did not report childhood eczema in the questionnaire. There was a difference between those who did recall their childhood AD (remembering group, RG), and those who did not (forgetful group, FG) in who had documented the diagnostic signs in the school health records. In the RG the signs were reported by both parents and school health personnel in 51% of cases, and in the FG this was true of only 16%. The RG had a higher prevalence of eczema after 15 years of age and of hand eczema. The RG also reported more visits to physicians after the age of 15 years and more time taken as sick leave due to eczema.

CONCLUSIONS

Several factors influence how well people remember their AD in childhood. These factors include disease activity in adult life, disease severity, and who noticed the eczema in childhood.

Occupational skin disease in Sweden - a 12-year follow-up

The aim of this project was to study the long-term prognosis of occupational skin diseases in Sweden. In 1999, a questionnaire was sent to 623/655 individuals who in 1987 reported occupational skin disease to the Social Insurance Office. 394 answered the questionnaire, and 123 non-responders were interviewed by telephone, giving 517 participants (83%), 323 females and 194 males. 85% reported skin symptoms after 1987, 70% during the previous year. 28% considered themselves recovered, of those with nickel allergy only 12%. In a logistic regression model, skin atopy was the strongest unfavourable factor for the prognosis followed by contact allergy and female sex. 66% had consulted a doctor after 1987 and the majority, 82%, had performed occupational changes - most common was change of jobs, 44%. Those who had changed jobs reported less sick leave. The conclusion is that occupational skin diseases have a clear tendency to end up as chronic conditions with a majority reporting symptoms at a 12-year follow-up. The skin disease had influenced the occupational situation for the majority (82%) and for 15% resulted in exclusion from the labour market through unemployment or disability pension.

Fifteen-year follow-up of hand eczema: persistence and consequences

BACKGROUND

Hand eczema is a skin disease often with a long-lasting and relapsing course. The long-term prognosis in the general population is unknown.

OBJECTIVES

The aims were to examine the extent to which hand eczema had persisted and the medicosocial consequences of the disease.

METHODS

In a 15-year follow-up of hand eczema, patients diagnosed in a previous population-based study were sent a questionnaire with 20 questions concerning the persistence and course of the disease, and its occupational and medicosocial consequences.

RESULTS

Addresses were available for 1115 persons, of whom 868 answered the questionnaire. Sixty-six per cent of the respondents reported periods of hand eczema and 44% reported symptoms during the previous year, with no sex difference. Twelve per cent reported continuous eczema. However, 74% of those reporting symptoms considered that their hand eczema had improved; of these more were women than men (78% vs. 66%, P < 0.01). Twenty people, 3% of those who were gainfully employed in 1983, reported a change to another occupation because of their hand eczema, 15 of these reporting improvement after the job change. A considerable need for medical consultation was reported, as was the influence on psychosocial functions among those who had eczema the previous year, e.g. sleep disturbances (36%) and hampered leisure activities (72%). Job changes related to hand eczema and psychosocial impairment were also reported by individuals who had not sought medical help for their hand eczema.

CONCLUSIONS

This study demonstrates a variable and poor long-term prognosis for hand eczema in the general population. One-third sought medical care during follow-up, while the vast majority with ongoing hand eczema experienced negative psychosocial consequences. For about 5%, the hand eczema gave far-reaching consequences including long sick-leave periods, sick pension and changes of occupation.

Nordic Occupational Skin Questionnaire (NOSQ-2002): a new tool for surveying occupational skin diseases and exposure

Occupational skin diseases are among the most frequent work-related diseases in industrialized countries. Good occupational skin disease statistics exist in few countries. Questionnaire studies are needed to get more data on the epidemiology of occupational skin diseases. The Nordic Occupational Skin Questionnaire Group has developed a new questionnaire tool - Nordic Occupational Skin Questionnaire (NOSQ-2002) - for surveys on work-related skin disease and exposures to environmental factors. The 2 NOSQ-2002 questionnaires have been compiled by using existing questionnaires and experience. NOSQ-2002/SHORT is a ready-to-use 4-page questionnaire for screening and monitoring occupational skin diseases, e.g. in a population or workplace. All the questions in the short questionnaire (NOSQ-2002/SHORT) are included in the long version, NOSQ-2002/LONG, which contains a pool of questions to be chosen according to research needs and tailored to specific populations. The NOSQ-2002 report includes, in addition to the questionnaires, a comprehensive manual for researchers on planning and conducting a questionnaire survey on hand eczema and relevant exposures. NOSQ-2002 questionnaires have been compiled in English and translated into Danish, Swedish, Finnish and Icelandic. The use of NOSQ-2002 will benefit research on occupational skin diseases by providing more standardized data, which can be compared between studies and countries.

Hand eczema in 45 bakers - a clinical study

The skin of bakers is heavily exposed to dough, spices, water and detergents. This is follow-up of a previous Swedish questionnaire study showing bakers to have a 3-fold increased risk of hand eczema. The aims were to establish diagnoses and to study consequences of hand eczema. From a cohort study of 2226 bakers, a random sample among bakers reporting hand eczema was examined. Of 60 randomly selected bakers reporting a history of hand eczema, 52 attended an examination comprising a standardized interview, documentation of clinical skin signs, patch testing and prick testing with standard and bakery series, and serum analyses. In all, 45 bakers confirmed a history of hand eczema, for which 11 (24%) had been on sick leave, with a median duration of 14 weeks. 13 (29%) had changed their occupation due to skin disease, 19 had positive patch test reactions to standard contact allergens - and 5 to bakery contact allergens. 16 bakers had positive prick tests to standard allergens, 10 to bakery allergens, of whom 9 reacted to flours. Since considerable medical and social consequences of hand eczema are seen, thorough diagnosis of contact allergy and IgE-mediated allergy in bakers, as well as preventive measures, are essential.

Self-reported hand eczema: symptom-based reports do not increase the validity of diagnosis

BACKGROUND

Hand eczema is a common skin disease that affects about 10% of the general population of working age in Sweden. The resulting long sick-leave periods and need for changes of work and re-training put an economic burden on society, and there is an interest in developing cost-effective epidemiological surveillance instruments such as a screening questionnaire.

OBJECTIVES

In a search for a simple screening questionnaire for hand eczema we compared the validity of a question about the presence of hand eczema with hand eczema diagnosis based on self-reported signs.

METHODS

Consecutive patients (n = 95) referred for hand eczema and people in an ongoing epidemiological survey (n = 113) participated in the study. Before seeing an experienced dermatologist they had to: (1) answer a short questionnaire about current signs and symptoms from the hands; and (2) state whether they had hand eczema on the day of examination. The minimum criteria for hand eczema diagnosed by the dermatologist ('gold standard') were erythema and papules or vesicles, or erythema and scaling and fissures/lichenification.

RESULTS

Of the 208 persons examined 93 fulfilled the criteria for hand eczema according to the 'gold standard'. Hand eczema diagnosis based on clinical signs reported in the questionnaire by the participants gave a sensitivity of 0.62 and a specificity of 0.87 in comparison with the dermatologists' diagnoses. Regarding the question about current hand eczema, agreement was good between the participants' and the dermatologists' judgements, giving a sensitivity of 0.87 and a specificity of 0.79. Comparing clinical signs reported by the participants and the findings by the dermatologists, the best agreement was for fissures, with a kappa-value of 0.65 (95% CI 0.55-0.75), and the poorest was for papules with 0.47 (95% CI 0.32-0.62).

CONCLUSIONS

It was difficult for the individual to identify skin signs compatible with the clinical diagnosis of hand eczema. Asking 'Do you have hand eczema?' had high sensitivity and specificity compared to the suggested gold standard for hand eczema. However, the validity of a screening questionnaire depends on the type of population investigated.

Incidence of asthma in female Swedish hairdressers

OBJECTIVE

To investigate the risk of asthma in hairdressers.

METHODS

The incidence of asthma was retrospectively estimated in a Swedish nationwide study including all female hairdressers certified from vocational schools from 1970 to 1995, and a stratified sample of women from the general population were referents. A postal questionnaire included questions on respiratory tract symptoms, atopy, smoking, working periods as a hairdresser, and number of specific hair treatments performed/week. Reported exposures were validated by occupational hygienists. Rate ratios of incidence (IRRs) of asthma were estimated by Poisson regression, adjusted for calendar year of observation, hay fever, smoking, and region of domicile.

RESULTS

The crude incidences of asthma/1000 person-years were: 3.9 during active years as a hairdresser, 2.8 among the hairdressers when not working in the profession, and 3.1 among the referents. The corresponding IRR for being an active hairdresser compared with the referents was 1.3 (95% confidence interval (95% CI) 1.0 to 1.6). Moderate effects on risk of asthma were found both from hairdressing work (IRR=1.6 (1.1 to 2.2) among never-smokers) and from smoking (IRR=1.6 (1.2 to 2.2) among referents). However, the combined effect from hairdressing work and smoking (IRR=1.5 (1.0 to 2.1)) was less than expected (p=0.02). No effect modification by respiratory atopy was found. The hairdressers most often performing hair bleaching treatments (IRR=1.5 (0.7 to 3.0)) or using hair spray (IRR=1.4 (0.8 to 2.4)) had, compared with the most infrequent users, a slightly, but not significantly higher incidence of asthma. Exposure to persulphates in hair bleach was estimated to be 0.04-0.15 mg/m(3) during mixing of the powder. Reported average number of bleaching treatments agreed well with those performed according to a diary.

CONCLUSIONS

Active hairdressing work was associated with a moderately increased incidence of asthma among lifelong non-smokers. The results are moderately supportive, but not conclusive, of associations between asthma and exposure to hair bleach or hair spray.

Self-diagnosed dermatitis in adults. Results from a population survey in Stockholm

In a population-based survey of public health issues in Stockholm, Sweden, self-reported hand eczema, history of childhood eczema, nickel allergy, occurrence of skin symptoms on the face and intolerance to cosmetics and hygiene products, were investigated. A postal questionnaire was sent to 15,000 inhabitants aged 19-80 years. The response rate was 73%. The 1-year prevalence of hand eczema was 8% (females 10%, males 6%). History of childhood eczema was reported by 15% and, of these, 42% also stated positively that they had had hand eczema at some time. Hypersensitivity to nickel was owned to 15% of the females and 3% of the males. Of the nickel-sensitive, 30% reported ever having had hand eczema. The combination of nickel allergy and history of childhood eczema resulted in a cumulative prevalence of hand eczema of 56%. Females reported more hand-washings per day than did males, and a relation between number of hand-washings and hand eczema was found. Self-reported 1-year prevalence of skin symptoms on the face was 14% and, of these, 33% also owned to hypersensitivity to cosmetics. Dermatitis appears to be a common health problem. This fact should be made clear to those who give priority and allocate resources to health problems, e.g., by participation of dermatologists in performing population-based surveys.

Occupational dermatitis in dental personnel: contact dermatitis with special reference to (meth)acrylates in 174 patients

Between 1995 and 1998, 174 dental personnel were referred as patients to the Department of Occupational and Environmental Dermatology, Stockholm. After clinical examination, 131 were patch tested with the Swedish standard series and 109 with a dental screening series. Furthermore, 137 were tested for IgE-mediated allergy to natural rubber latex (NRL). Hand eczema was diagnosed in 109/174 (63%), 73 (67%) being classified as irritant contact dermatitis and 36 (33%) as allergic. Further diagnoses included other eczemas, urticaria, rosacea, psoriasis, tinea pedis, bullous pemphigoid or no skin disease. 77/131 (59%) had positive reactions to substances in the standard series and 44/109 (40%) to substances exclusive to the dental series. 24/109 (22%) patients had positive reactions to (meth)acrylates, the majority with reactions to several test preparations. Reactions to HEMA (2-hydroxyethyl methacrylate), EGDMA (ethyleneglycol dimethacrylate) and MMA (methyl methacrylate) were most frequent. 9 of the 24 were positive only to (meth)acrylates, the remaining 15 also had reactions to allergens in the standard series. 23 of these had hand eczema and 1 facial eczema. In 17 of the 24 allergic to (meth)acrylates, the dermatitis had started in 1995 or later, in 15 within the previous 12 months. Of 8 who had been sick-listed, 7 also had a history of atopy and 6 were allergic to nickel. The most frequent allergens besides (meth)acrylates were nickel, cobalt, palladium, fragrance mix, colophonium and thiuram mix. Allergy to natural rubber latex was diagnosed in 14/137 (10%). In conclusion, irritant hand dermatitis was the dominant diagnosis. Contact allergy to (meth)acrylate was seen in 22% of the patch tested patients, with reactions to 3 predominant test substances. 1/3 of the patients with allergy to (meth)acrylates had been sick-listed for dermatitis, but in all these cases the (meth)acrylate allergy was seen together with atopy and/or further contact allergies.

Validity of self-reports of hand eczema

The validity of questionnaire answers with respect to hand eczema was investigated. Car mechanics, dentists and office workers answered a questionnaire on the occurrence of hand eczema on any occasion during the past 12 months. "Yes"-responders and a random sample of "no"-responders were subsequently interviewed and examined by a dermatologist. 10.0% of the car mechanics, 12.0% of the dentists and 12.5% of the office workers were found to have hand eczema despite previous "no"-answers. In the same populations, 81%, 94% and 80% of the "yes"-answers were confirmed at the clinical examination. Considering false-negative and false-positive answers, the sensitivity was 53-59% and the specificity 96-99% in the 3 groups. The 1-year prevalence changed from self-reported 15% to estimated 21% in the car mechanics, from 15% to 24% in the dentists and from 15% to 23% in the office workers. It is concluded that self-reported 1-year prevalence of hand eczema considerably underestimates the true prevalence.

Protective gloves in Swedish dentistry: use and side-effects

BACKGROUND

During the 1980s routine wearing of gloves in dentistry was recommended by health authorities in several countries. However, prolonged glove use is associated with side-effects of irritant and allergic origin.

OBJECTIVES

To investigate the extent of glove use and self-reported glove intolerance reactions among Swedish dentists, and to examine how far IgE-mediated allergy to natural rubber latex (NRL) occurs in subjects who report rapid itching when in contact with protective gloves.

SUBJECTS/METHODS

A postal questionnaire was answered by 3083 of 3500 licensed dentists, a response rate of 88%. Of the dentists who reported rapidly occurring itching of the hands from gloves, 131 of 170 attended a clinical examination including a skin prick test (SPT) and a serological examination (RAST) for IgE-mediated allergy.

RESULTS

Seventy-three per cent of the dentists reported daily glove use of more than 2 h, 48% more than 6 h a day, and 6% reported no use. NRL gloves were used most frequently (P < 0.001) and were the main material that elicited symptoms (P < 0.001). Female dentists reported more frequent glove use than males, as did young dentists (P < 0.001) compared with older ones. Females also preferred vinyl gloves. Glove intolerance reactions were reported by 723 (23%) dentists, [females 28%, males 21% (P < 0.001)] and were more common in younger dentists. Of the 417 dentists with reported hand eczema during the previous year, 54% reported glove intolerance, compared with 20% of the dentists without hand eczema (P < 0.001). A logistic regression analysis including hand eczema, age, sex and atopy showed that all these factors contributed significantly to the risk of glove intolerance, and that hand eczema was a stronger factor than atopy. In 15 of 131 (11%) dentists examined for reported glove-related itch, latex allergy was verified by SPT and/or RAST. Glove-related conjunctivitis, rhinitis and asthma, in contrast to skin symptoms, showed a significant association with IgE-mediated allergy to NRL.

CONCLUSIONS

Swedish dentists show good compliance with the recommendations for routine glove use. Intolerance reactions are frequently reported, especially by dentists with hand eczema, which emphasizes the need for preventive skin care programmes. Glove-related symptoms from mucous membranes showed a higher association with IgE-mediated allergy to NRL than reported itching of the skin, a fact that should be considered when composing screening questionnaires for NRL sensitization

Contact allergy and hand eczema in Swedish dentists

Hand eczema and contact allergy in Swedish dentists were studied in a multidisciplinary project. The aims of the study were to establish diagnoses, to investigate the occurrence of contact allergy, in particular to (meth)acrylates, and to evaluate certain consequences of hand eczema. A postal questionnaire on skin symptoms, atopy and occupational experience was mailed to 3,500 dentists aged <65 years, and licensed 1965-1995. The response rate was 88%. Among dentists living in 3 major cities, 14.9% (n= 191) reported hand eczema during the previous year. They were invited to a clinical examination, including patch testing with a standard and a dental series. 158/191 (83%) dentists attended, and hand eczema diagnosis was confirmed in 149/158 (94%). Irritant contact dermatitis was diagnosed in 67% and allergic contact dermatitis in 28%. On patch testing, 50% presented at least 1 positive reaction. The most frequent allergens were nickel sulfate, fragrance mix, gold sodium thiosulfate and thiuram mix. 7 (5%) had positive reactions to (meth)acrylates, all to 2-hydroxyethyl methacrylate and 6 also to ethyleneglycol dimethacrylate. 38% had consulted a physician, 4% had been on sick-leave and 1% had changed occupational tasks due to hand eczema. No dentist with allergy to acrylates had been on sick-leave or changed occupation. It is concluded that dentistry is a high-risk occupation for hand eczema, and that irritant contact dermatitis is most common. The prevalence of contact allergy to acrylates was below 1% in the population of responding dentists, and in most cases did not have serious medical, social or occupational consequences.

Differences between the sexes with regard to work-related skin disease

Work-related skin disease is common and usually presents as hand eczema. From the Occupational Injury Information System in Sweden, as well as from registers of industrial injuries in other countries, it is evident that females report skin disease more often than males. Epidemiological studies of hand eczema also show that women are more often affected than men, in particular young women. The most common type of hand eczema is irritant contact dermatitis, which is often caused by wet work. Many female-dominated occupations involve extensive wet work, e.g., hairdressing, catering, cleaning and health-care work. These occupations are also high-risk occupations for hand eczema. Experimental studies of skin irritation have not confirmed differences between the sexes; thus, the higher prevalence of irritant contact dermatitis among females is most likely due to exposure, occupational and non-occupational. Nickel allergy is the most common contact allergy, which is most frequent in young females, and in 30-40% results over time in hand eczema. Hand eczema has an impact on quality of life and females seem to report a higher degree of discomfort than males. To achieve the optimal effect of preventive efforts regarding occupational skin disease, the focus for prevention should aim at reducing wet exposure.

Prevalence of self-reported hand eczema and skin symptoms associated with dental materials among Swedish dentists

In the present study we investigated the prevalence of self-reported hand eczema as well as subjective associations between skin symptoms and composite/bonding or other dental materials among Swedish dentists. A questionnaire on skin symptoms, atopy, occupational experience, and other background factors was sent to a random sample (n=3,500) of all dentists licensed since 1965. This group corresponds to about half of the country's occupationally active dentists. The response rate was 88%. The questionnaire had previously been validated against clinical dermatological examination of subjects reporting hand eczema. The prevalence of dry and rough skin on the hands was high (45%). Hand eczema during the previous 12 months was reported by 13.5%. Dry skin and hand eczema were more common among dentists than in two age-matched general population samples investigated using identical questions. The difference versus the general population was most pronounced (about two-fold) among male dentists. A history of childhood eczema was the most important predictor for adult hand eczema, with a prevalence ratio of 2.4 compared to dentists without childhood eczema. Seven % reported skin symptoms when working with acrylic resins, and 15% had experienced rapid itching related to protective gloves.

Occurrence of self reported hand eczema in Swedish bakers

OBJECTIVES

To estimate the risk of bakers developing hand eczema. The importance of atopy was studied as well as change of job due to hand eczema.

METHODS

A retrospective cohort study was performed among bakers trained in Swedish trade schools in 1961-89 (n = 2923). School referents followed other programmes (n = 1258); population controls were randomly selected from the general population (n = 1258). A questionnaire on self reported hand eczema, year of onset of hand eczema, change of work due to hand eczema, childhood eczema, family atopy, and work history was posted to all participants.

RESULTS

The incidence of hand eczema among male controls was 4.4-5.4 cases/1,000 person-years compared with 16.7 for bakery work. The corresponding figures for women were 11.3-14.1 compared with 34.4. The relative risk for male bakers was 3.5 (95% confidence interval (95% CI) 2.8 to 4.5) and for female bakers 2.8 (2.2 to 3.6). Skin atopy increased the incidence about threefold and a synergistic effect of atopy and exposure was indicated. Also, bakers had changed job significantly more often than controls.

CONCLUSIONS

Swedish bakers, mainly working during the 1970s and 1980s, have about a threefold increased risk of hand eczema. There seems to be a synergistic effect of atopy and occupational exposure.

Variability in the skin exposure of machine operators exposed to cutting fluids

OBJECTIVE

This study describes a new technique for measuring skin exposure to cutting fluids and evaluates the variability of skin exposure among machine operators performing cyclic (repetitive) work.

METHODS

The technique is based on video recording and subsequent analysis of the video tape by means of computer-synchronized video equipment. The time intervals at which the machine operator's hand was exposed to fluid were registered, and the total wet time of the skin was calculated by assuming different evaporation times for the fluid. The exposure of 12 operators with different work methods was analyzed in 6 different workshops, which included a range of machine types, from highly automated metal cutting machines (ie, actual cutting and chip removal machines) requiring operator supervision to conventional metal cutting machines, where the operator was required to maneuver the machine and manually exchange products.

RESULTS

The relative wet time varied between 0% and 100%. A significant association between short cycle time and high relative wet time was noted. However, there was no relationship between the degree of automatization of the metal cutting machines and wet time.

CONCLUSIONS

The study shows that skin exposure to cutting fluids can vary considerably between machine operators involved in manufacturing processes using different types of metal cutting machines. The machine type was not associated with dermal wetness. The technique appears to give objective information about dermal wetness.

Late skin-prick-test reactions to malted wheat. Clinical observations and immunohistochemical characterization

This study reports late skin-prick-test (SPT) reactions in seven bakers and seven control subjects to malted wheat appearing after 6-10 h, and not preceded by an immediate-phase reaction. Two subjects in each group had a history of atopic symptoms and were Phadiatope positive. Serologic IgE analysis (RAST) of normal wheat flour and of malted wheat grain was negative in all subjects. Skin biopsy specimens were obtained 16-18 h after SPT to malted wheat grain and to histamine and from untested skin. The late SPT reactions in all participants had an urticarial appearance, clinically and in routine histology. Immunohistologically mild to moderate perivascular dermal cell infiltrates were observed in both groups, consisting mainly of CD4+ and HLA-DR+ cells. The number of CD1a+ epidermal cells was statistically significantly higher (P < 0.01) in the bakers' prick-tested skin compared to that of the controls, a fact which might reflect preparedness to react upon challenge. There were no statistical differences between the two groups in IgE+ epidermal cells or epidermal cells expressing the high-affinity IgE receptor (Fc epsilon RI). However, there was a correlation between serum-IgE levels and the number of IgE+ epidermal cells. The late skin reactions observed in both bakers and controls were probably more of an irritant or toxic than immune-mediated nature, but they raise the question of whether skin contact with malted flour contributes to an unfavorable prognosis of hand eczema in bakers.

Potential side effects of dental amalgam restorations. (I). An oral and medical investigation

The aim of this study was to explore a possible association between health status and self-reported adverse effects related to dental amalgam restorations. A group of 50 consecutive patients (index group), referred for complaints self-related to dental amalgam restorations, was compared with a control group of individuals matched by age, sex and postal zip code. The patients underwent an oral, stomatognathic, medical and clinical chemistry examination. Mercury levels were examined in blood, urine and hair. The results revealed that somatic diseases were more common in the index group (38% versus 6%). Symptoms related to cranio-mandibular dysfunction were reported by 74% of the patients in the index group versus 24% in the control group, and were diagnosed in 62% and 36%, respectively. The oral health status and the number of amalgam surfaces were similar in the 2 groups. No positive skin patch test to mercury was found in any of the groups. The estimated mercury intake from fish consumption, occupational exposure, and mercury levels in blood and urine were also similar and far below levels, where negative health effects would be expected. The correlation between the number of amalgam surfaces and mercury levels in plasma and urine (r=0.43) indicated a release of mercury from dental amalgam restorations in both groups. Since the mercury levels were similar among index patients and controls, mercury was not a likely cause of the impaired health reported by the patients.

Sensitization and exposure to methylisothiazolinones (Kathon) in the pulp and paper industry--a report of two cases

Two cases of contact allergy to methylisothiazolinones from slimicides used in pulp and paper mills are described. The first patient worked as a batcher in a paper mill, and he was in charge of pumping slimicides containing methylisothiazolinones. During pumping, the liquid often overflowed, and his clothes were wet daily with slimicides. After 3 months of work, he began to suffer from dermatitis, which improved when he was away from work. A clinical investigation confirmed the dermatitis diagnosis and a positive skin patch test to Kathon CG was found. The second patient worked as an agent for a firm marketing slimicides containing methylisothiazolinones. One of his tasks was to pump slimicides into the mills, and during such operations his clothes often got wet from slimicides. After some years of work, he began to suffer from erythema and dermatitis after contact with the slimicides. A skin patch test showed a strongly positive reaction to Kathon CG. These case reports draw the attention to the fact that employees in the pulp and paper industry handling slimicides are exposed to extraordinarily high concentrations of methylisothiazolinones and run a substantial risk of being sensitized. The report also stresses the need for improved handling routines of those strong sensitizers in the paper mills.

Airborne contact dermatitis from unexpected exposure to rosin (colophony). Rosin sources revealed with chemical analyses

We report 3 cases of contact dermatitis in rosin-sensitive individuals caused by exposure to airborne rosin components from different sources. Case no. 1 was a female office worker with a facial dermatitis caused by rosin components which emanated from the linoleum floor covering in her office. Floor material containing wood flour and rosin was released into the air, causing a facial dermatitis in the rosin-sensitive subject. Case no. 2 involved a woman who worked in a factory producing dairy product cartons and had a dermatitis on her lower legs, lower arms and upper chest. Her dermatitis was caused by dust from the paper cartons and contact allergy to rosin components probably aggravated her dermatitis. Case no. 3 was a female office worker with a relapsing dermatitis on her eyelids. Her dermatitis was caused by a rosin-containing floor polish, which was seen as a powder on the office floor. Extracts of suspected material and products were patch tested and analysed for the presence of rosin components with HPLC and GC techniques. A discussion and recommendations on chemical analyses of rosin components follow. We conclude that a thorough investigation, including chemical analyses, can rule out non-specific diagnoses and offer a solution to the patient's skin problems.

Wood dust from jelutong (Dyera costulata) causes contact allergy

Jelutong is the wood from Dyera costulata growing in south-east Asia. It is soft and easy to work and is used in, e.g., model workshops in car factories. It has also been much used in woodwork teaching in Swedish comprehensive schools. To estimate the prevalence of contact allergy to jelutong, 84 woodwork teachers and 110 consecutive dermatitis patients were patch tested with extract from wood dust of jelutong. 16/84 (19%) teachers had positive reactions. When they were tested with a dilution series, positive reactions were obtained for 6 mg and down to 0.3 mg of the extracted material. Half the test-positive teachers had skin symptoms that might be related to exposure to jelutong 4/110 dermatitis patients at the clinic also had positive reactions, and possible exposure to jelutong was traced in 3 of them. 3 other dermatitis patients had flare-up reactions after about 2 weeks, indicating patch-test sensitization. To investigate the sensitizing capacity of the extract, the cumulative contact enhancement test was performed in guinea pigs. This confirmed that the extracted material was sensitizing, and a clear dose-response relationship was found. The schools will be recommended to use safer wood alternatives in woodwork teaching.

Skin symptoms and contact allergy in woodwork teachers

To estimate the occurrence of skin symptoms and the prevalence of contact allergy to occupational allergens, 84 male woodwork teachers were interviewed, clinically examined and patch tested. The tests included a supplemented European standard series and acetone extracts of wood dust of pine, spruce, juniper and birch. In addition, 10 colophony-allergic volunteers were tested with dilution series of wood dust extracts. Major colophony compounds in the dust extracts were analyzed with gas chromatography. We found a high 1-year period prevalence of generally mild hand eczema: 19%. Contact allergy was diagnosed to several allergens in the working environment, e.g., benzisothiazolin-3-one, nickel, formaldehyde and colophony. A clear relationship between patch test reactions to colophony and to coniferous woods, especially pine, was found. Exposure to wood dust at work caused dermatitis in a colophony-sensitized teacher.

Hand eczema in car mechanics

To estimate the prevalence of hand eczema, a questionnaire was distributed to 901 male car mechanics. Of the 801 persons who responded, 15% reported hand eczema on some occasion in the previous 12 months, and 57% admitted dry skin on the hands. In a 2nd part of the study, those who reported hand eczema were examined and patch tested with a standard series and a special "car mechanics' series". The most common diagnosis was irritant contact dermatitis, 55%, and 2nd was allergic contact dermatitis, 19%. 35/105 (33%) had a total of 51 positive patch test reactions, all to substances in the standard series, except for 2 persons who reacted to oxidized d-limonene. The most frequent reactions were to thimerosal (9%), nickel (8%) and colophony (5%). One plausible explanation for the high prevalence of nickel allergy was the common use of nickel-plated tools. 5 individuals had a history of contact urticaria, but scratch tests were negative. It was concluded that car mechanics are at high risk for contact dermatitis on the hands, irritant as well as allergic.

Skin symptoms among workers in a spice factory

Workers in a Swedish spice factory (n = 70), and in the office (n = 23) of the same company, were investigated by questionnaire regarding skin symptoms. In a 2nd part of the study, subjects reporting skin symptoms were examined and investigated by patch and prick testing. Skin symptoms were reported by 1/2 the factory workers. Pruritus and skin irritation, particularly from cinnamon powder, were common. Patch test reactions to cinnamic aldehyde were found in 11/25 factory workers, but in several cases, the nature of the reactions was difficult to evaluate. Irritant patch test reactions were seen from powders of cardamom, paprika and white pepper. On prick testing, 6/25 workers reacted to cinnamic aldehyde. The results illustrate the difficulties of patch testing with spices and indicate the need for further research and validation of methods.

Evaluation of skin symptoms among workers at a Swedish paper mill

Process and office workers at a Swedish paper mill (n = 274) and dairy workers (n = 45) were investigated with questionnaires regarding skin symptoms. In the second part of the study, subjects reporting skin symptoms and a random sample of subjects without symptoms were examined and investigated with patch testing. Pruritus and skin irritation probably related to exposure to dust were found. The results do not indicate an increased prevalence of contact allergy. In two cases, positive patch test reactions to paper size (rosin) and a slimicide, mercaptobenzothiazole (MBT), were noted.

Asthma, rhinitis, and dermatitis in workers exposed to reactive dyes

A survey was conducted at 15 textile plants with dyehouses in western Sweden. Employees with a history of work related rhinitis, asthma, or skin symptoms were offered a clinical and immunological investigation including skin prick tests, skin patch tests, and radioallergosorbent tests (RASTs) to detect specific allergy to reactive dyes. Among the 1142 employees, 162 were exposed to reactive dyes and 10 of these (6%) reported work related respiratory or nasal symptoms. An allergy to reactive dyes could be confirmed in five (3%, 95% confidence interval 1-7%). All but one had been exposed to reactive dyes for one year or less before the onset of symptoms. Positive RASTs could be detected in four of the five patients. All of the RAST positive patients were positive to remazol black B, but six out of eight additional remazol dyes also elicited positive results. RAST and RAST inhibition showed a cross reactivity between some of the dyes. Seven persons with work related dermatitis and three with urticaria or Quincke oedema were found. In one patient contact dermatitis to a monoazo dye was shown, but no positive patch test reactions to reactive dyes. IgE-mediated allergy to reactive dyes seems to be an important cause of respiratory and nasal symptoms among dyehouse employees exposed to dust from reactive dyes.