Increased rates of fragrance allergy in fibromyalgia individuals tested with the Swedish baseline patch test series.

BACKGROUND: Contact allergy can manifest in a variety of ways clinically. Systemic contact allergy may occasionally present with pain in muscles and joints. Fibromyalgia is a chronic rheumatic disease characterized by pain and with virtually unknown aetiology. OBJECTIVES: The aim of this study was to investigate the contact allergy rates to the sensitizers in a baseline series and compare with corresponding rates in dermatitis patients and the general population. METHODS: Patch testing with the Swedish baseline series was performed in 120 individuals with fibromyalgia. Fisher's exact test was used for pair-wise comparisons of contact allergy rates between the fibromyalgia group and two control groups, dermatitis patients and individuals in the general population. RESULTS: Contact allergy was significantly more common in the fibromyalgia group compared to the general population concerning nickel and the fragrance markers Myroxolon pereirae and fragrance mix I. There were fewer allergic reactions to preservatives in the fibromyalgia group compared with the dermatitis group. CONCLUSIONS: Myroxolon pereirae and fragrance mix I represent besides fragrance allergy also allergy to flavouring substances which indicate that oral exposure to flavouring substances and hygiene products might be important for sensitization and possibly elicitation of systemic contact allergy symptoms in fibromyalgia individuals.

Allergic Contact Dermatitis to Operating Room Scrubs and Disinfectants.

BACKGROUND: Both surgical personnel and patients undergoing procedures are exposed regularly to different antiseptic chemicals in various forms. Little is known about the ingredients in these antiseptics and the risk these products may provoke allergic contact dermatitis. OBJECTIVE: The aim of the study was to identify and characterize common allergens in surgical scrubs and patient surgical cleansers that health care workers and surgical patients may encounter in the perioperative period. METHODS: DailyMed website was searched using numerous terms for surgical disinfectants. Products used for health care worker handwashing/scrubbing or patient surgical cleansing/disinfecting were included. Each product's ingredients were recorded; those found on the 2017 American Contact Dermatitis Society (ACDS) Core Allergen Series were noted from each product. CONCLUSIONS: A total of 1940 products were identified, of which 267 were included in the analysis. A total of 66.3% contained iodine, 25.8% contained chlorhexidine digluconate, and 2.6% contained chloroxylenol. Within the group analyzed, 1586 ingredients were identified. Of these, 241 were ACDS Core Series allergens. Most products contained a single ACDS allergen. There were significant differences in allergens based on product type and active ingredient, with iodine-containing products having the fewest number of allergens. The most common ACDS allergens found were cocamide diethanolamide (22.5%), fragrance (21.7%), lanolin (19.5%), propylene glycol (6.7%), alkyl glucosides (6.0%), and sorbic acid derivatives (5.6%).

Characterization and Triggers of Dyspnea in Patients with Chronic Obstructive Pulmonary Disease or Chronic Heart Failure: Effects of Weather and Environment.

BACKGROUND AND OBJECTIVES: Dyspnea is one of the most disturbing symptoms for patients with chronic obstructive pulmonary disease (COPD) or heart failure (HF). This study investigated dyspnea triggers and factors associated with worsening dyspnea in patients with COPD or HF. METHODS: COPD support group members and HF patients with reduced ejection fraction (HFrEF) and no airway obstruction answered a questionnaire describing different weather conditions (rising/falling air pressure, sunny, foggy, rainy, windy, snowy, hazy, high ozone levels, and airborne pollen) and environmental circumstances (cooking, grilling, perfumes, cigarette smoke, gasoline odor, and flower scents) and were asked to estimate the occurrence and severity of dyspnea under these conditions using predefined scales. RESULTS: 230 patients with COPD and 90 with HFrEF (left ventricular ejection fraction 34 ± 10%, Tiffeneau index > 70%) were analyzed. COPD patients reported dyspnea more often than HF patients in almost all weather and environmental conditions (p = 0.004 to p < 0.001), with the exception of outdoor floral scents and cigarette smoke. Severe to very severe dyspnea was reported more in COPD versus HF in all weather and environmental conditions except sunny weather (p = 0.01 to p < 0.001). COPD was associated with more severe dyspnea than HF in all conditions (all p < 0.001). CONCLUSIONS: Dyspnea was triggered by a variety of weather and other environmental triggers in patients with COPD and occurred more often than in HF patients under the same conditions. Foggy weather and exposure to perfumes were associated with severe dyspnea in the majority of COPD patients, but only a minority of HF patients.

Positive results of patch tests with fragrance markers: analysis of a 15-year period at a Brazilian dermatology center

Abstract: Fragrances may cause allergic contact dermatitis. Data on patients who were patch tested, between 2000 and 2015, with fragrance allergens included in the Brazilian baseline series (balsam of Peru, colophony and fragrance mix I), were collected and analyzed. Of these patients, 258 (13.8%) were positive for fragrance markers, 9.8% being positive for fragrance mix I. Among these 258 there was a predominance of women in their 40s, with hand eczema. The frequency of sensitization to fragrances, as well as the epidemiological profile, was supported by the literature. Fragrance mix I was the main marker. It is important to expand the fragrance markers used in the Brazilian baseline series of patch tests.

Common allergens present in personal care products: identification, diagnosis, and management.

The incidence of allergic contact dermatitis (ACD) reactions to personal care products has progressively increased, affecting women more so than men. Fragrances and preservatives are the major sensitizers behind cosmetic-induced ACD, due to their ubiquitous presence in these products, though emulsifiers, ultraviolet filters, and botanical allergens have been implicated as well. While patch testing is the standard for diagnosing ACD, many cosmetic-specific antigens are not currently included within the commercially available kits. Therefore, patch testing for potential cosmetic-induced ACD should be supplemented with additional compounds commonly found in personal use products. Effective treatment of ACD must involve accurate identification and removal of the offending agent.

Prevalence of Contact Allergens in Personal Care Products for Babies and Children.

BACKGROUND: Personal care products marketed for babies and children are often regarded as "safe" or "gentle." However, little is known about the prevalence of contact allergens in these types of products. OBJECTIVE: This study assessed the prevalence of important sensitizers in personal care products marketed for babies and children. A secondary objective of this study was to determine whether a product's cost correlates with content of sensitizing ingredients. METHODS: The ingredient lists of 533 unique personal care products were analyzed for presence of fragrance, betaines, propylene glycol, methylchloroisothiazolinone, methylisothiazolinone, formaldehyde, lanolin, and neomycin. Price per ounce was determined for each product as well. CONCLUSIONS: Most personal care products for babies and children contain 1 or more sensitizers. Products containing more sensitizers tend to cost less than those without any sensitizing ingredients.

UK trends of allergic occupational skin disease attributed to fragrances 1996-2015.

BACKGROUND: Fragrances are well known to cause allergic contact dermatitis (ACD). Occupationally related cases occur, with certain groups being at higher risk. OBJECTIVE: To investigate the incidence of occupationally related cases of cutaneous fragrance allergy and to evaluate trends. METHOD: Data on incident cases of occupational ACD caused by fragrances between 1996 and 2015 (inclusive) reported to the EPIDERM surveillance scheme were analysed. RESULTS: Of the cases reported to EPIDERM during the study period, 5.2% had ACD attributed to fragrances. The highest annual incidence rates were observed in women. Hairdressers, beauticians and people working in related occupations had a 47-fold higher incidence rate ratio than the reference category (the average of all other occupations combined). Trends analysis suggested a non-significant increase in fragrance allergy over the study period among all occupations, and beauty and food workers, and a slight decrease in healthcare workers. CONCLUSIONS: Fragrance allergy is a significant problem in an occupational setting. Although there was no significant change in the incidence of fragrance-related allergic occupational contact dermatitis (OCD) during the 20-year study period, this does not mirror the trend in OCD, which is falling. Fragrance allergy continues to be a major contributor to OCD, and contributes to a greater proportion of cases.

Contact Alopecia: Improvement of Alopecia with Discontinuation of Fluocinolone Oil in Individuals Allergic to Balsam Fragrance.

Inflammatory scalp dermatoses can be associated with alopecia, which is nonscarring and reversible in its early stages. This association has been described in seborrheic dermatitis, psoriasis, and atopic dermatitis. We describe three girls with alopecia aggravated by contact allergy to balsam fragrances. All three had complete resolution with avoidance of balsam of Peru and other balsam derivatives (including discontinuation of fluocinolone oil, which contains balsam of pine).

Pediatric Contact Dermatitis Registry Inaugural Case Data.

BACKGROUND: Little is known about the epidemiology of allergic contact dermatitis (ACD) in US children. More widespread diagnostic confirmation through epicutaneous patch testing is needed. OBJECTIVE: The aim was to quantify patch test results from providers evaluating US children. METHODS: The study is a retrospective analysis of deidentified patch test results of children aged 18 years or younger, entered by participating providers in the Pediatric Contact Dermatitis Registry, during the first year of data collection (2015-2016). RESULTS: One thousand one hundred forty-two cases from 34 US states, entered by 84 providers, were analyzed. Sixty-five percent of cases had one or more positive patch test (PPT), with 48% of cases having 1 or more relevant positive patch test (RPPT). The most common PPT allergens were nickel (22%), fragrance mix I (11%), cobalt (9.1%), balsam of Peru (8.4%), neomycin (7.2%), propylene glycol (6.8%), cocamidopropyl betaine (6.4%), bacitracin (6.2%), formaldehyde (5.7%), and gold (5.7%). CONCLUSIONS: This US database provides multidisciplinary information on pediatric ACD, rates of PPT, and relevant RPPT reactions, validating the high rates of pediatric ACD previously reported in the literature. The registry database is the largest comprehensive collection of US-only pediatric patch test cases on which future research can be built. Continued collaboration between patients, health care providers, manufacturers, and policy makers is needed to decrease the most common allergens in pediatric consumer products.

Concomitant contact allergies to formaldehyde, methylchloroisothiazolinone/methylisothiazolinone, methylisothiazolinone, and fragrance mixes I and II.

BACKGROUND: Contact allergies to the preservatives formaldehyde and methylchloroisothiazolinone (MCI)/methylisothiazolinone (MI) have been reported to appear together at a statistically significant level. Recently, revisions concerning the patch test preparations of MCI/MI, MI and formaldehyde have been recommended for the European baseline series. AIM: To investigate (i) the number of concomitant contact allergies to the preservatives, (ii) the number of concomitant contact allergies to the preservatives and the fragrance mixes (FM I and FM II) and (iii) gender differences. METHODS: Patients tested with the Swedish baseline series during the period 2012-2014 at the Department of Occupational and Environmental Dermatology in Malmö, Sweden were investigated. RESULTS: 2165 patients were patch tested with the baseline series (34% males and 66% females). Contact allergies to formaldehyde and MCI/MI and/or MI were significantly associated (p < 0.001). The associations between contact allergy to MCI/MI and/or MI and FM I and/or FM II, and between formaldehyde and FM I and/or FM II as well as, were statistically significant (p < 0.001). CONCLUSION: Contact allergies to formaldehyde and MCI/MI and/or MI are significantly associated, as well as contact allergies to these preservatives and fragrance allergy. Males and females do not differ significantly concerning contact allergy to fragrances.

Long-Term Follow-Up in Patients With Airway Chemical Intolerance.

OBJECTIVE: A 5-year follow-up study showed that a group of patients with airway symptoms from chemicals and scents had lasting symptoms, together with enduring increased capsaicin cough sensitivity. The aim was to follow up the same patients after another 5 years. METHODS: All previously participants were invited for an additional follow-up. They visited the clinic twice; at one opportunity, they undertook a capsaicin inhalation provocation, and at the other, a methacholine provocation, and answered various questionnaires. RESULTS: Sixteen patients attende the study after a median of 8 years. They reported unchanged symptoms from chemicals and scents; the capsaicin cough sensitivity was still increased, and the repeatability for the capsaicin inhalation was good. CONCLUSIONS: Airway symptoms induced by chemicals and scents constitute a chronic disease, with unchanged trigger factors, persistent symptoms, and unchanged, long-lasting sensory hyperreactivity.All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.This study was supported by grants from the Herman Krefting Foundation Against Asthma/Allergy, the Swedish Heart and Lung Foundation, and the Swedish Cancer and Allergy Fund.

Multicenter Patch Testing With a Resol Resin Based on Phenol and Formaldehyde Within the International Contact Dermatitis Research Group.

BACKGROUND: Contact allergy to phenol-formaldehyde resins (PFRs) based on phenol and formaldehyde is not detected by a p-tertiary-butylphenol-formaldehyde resin included in most baseline patch test series. OBJECTIVE: The aims of this study were to investigate the contact allergy rate to PFR-2 in an international population and to investigate associated simultaneous allergic reactions. METHODS: Thirteen centers representing the International Contact Dermatitis Research Group included PFR-2 into their patch test baseline series during a period of 6 months in 2012. RESULTS: Of 2259 patients tested, 28 (1.2%) reacted to PFR-2. Of those 28 individuals, one had a positive reaction to formaldehyde and 2 to p-tertiary-butylphenol-formaldehyde resin. Simultaneous allergic reactions were noted to colophonium in 3, to Myroxylon pereirae in 5, and to fragrance mix I in 8. CONCLUSIONS: The contact allergy frequency in the tested population (1.2%) merits its inclusion into the international baseline series and possibly also into other baseline series after appropriate investigations. Significantly, overrepresented simultaneous allergic reactions were noted for M. pereirae and fragrance mix I.

Effect of strong fragrance on olfactory detection threshold.

OBJECTIVE: To assess the olfactory threshold of healthy volunteers at the University College Hospital, Ibadan and to investigate the effect of perfume on their olfactory detection thresholds. STUDY DESIGN: A quasi-experimental study on olfactory detection thresholds of healthy volunteers from September 2013 to November 2013. SETTING: Tertiary health institution. SUBJECTS AND METHODS: A structured questionniare was administered to the participants in order to obtain information on sociodemographics, occupation, ability to perceive smell, use of perfume, effects of perfume on appetite and self-confidence, history of allergy, and previous nasal surgery. Participants subjectively rated their olfactory performance. Subsequently, they had olfactory detection threshold testing done at baseline and after exposure to perfume with varied concentrations of n-butanol in a forced triple response and staircase fashion. RESULTS: Healthy volunteers, 37 males and 63 females, were evaluated. Their ages ranged from 19 to 59 years with a mean of 31 years ± 8. Subjectively, 94% of the participants had excellent olfactory function. In the pre-exposure forced triple response, 88% were able to detect the odor at ≤.25 mmol/l concentration while in the post-exposure forced triple response, only 66% were able to detect the odor at ≤.25 mmol/l concentration. There is also a statistical significant difference in the olfactory detection threshold score between the pre-exposure and post-exposure period in the participants (P < .05). CONCLUSION: Use of strong fragrances affects the olfactory detection threshold. Therefore patients and clinicians should be aware of this and its effects on the outcome of test of olfaction.

Induction of CYP1A1, CYP1A2, CYP1B1, increased oxidative stress and inflammation in the lung and liver tissues of rats exposed to incense smoke.

Incense smoke is increasingly being recognized as a potential environmental contaminant and is linked to malignant and non-malignant respiratory diseases. The detoxification of environmental contaminants including polycyclic aromatic hydrocarbons (PAHs) involves the induction of cytochrome P-450 family enzymes (CYPs) by PAHs. However, the detoxification of PAHs also results in the generation of reactive and unstable intermediary metabolites which are implicated in the oxidative stress, DNA damage, and inflammation. It is unclear whether CYPs are similarly induced by incense smoke, which incidentally contains substantial amounts of PAHs. Here, we examined the impact of long-term incense smoke exposure on the induction of CYPs in male Wister Albino rats. Incense smoke exposure significantly induced the expression of CYP1A1, CYP1A2, and CYP1B1 mRNAs in both lung and liver tissues. The extent of CYP1A1 and CYP1B1 induction was significantly higher in the liver compared to that in the lung, while that of CYP1A2 was greater in the lung than in liver. Incense smoke exposure also increased malondialdehyde and reduced glutathione levels in lung and liver tissues, and the catalase activity in the liver tissues to significant levels. Furthermore incense smoke exposure led to a marked increase in TNF-α and IL-4 levels. The data demonstrate for the first time the capacity of incense smoke to induce CYP1 family enzymes in the target and non-target tissues. Induction of CYPs increased oxidative stress and inflammation appear to be intimately linked to promote the carcinogenesis and health complications in people chronically exposed to incense smoke.

Estudo da correlação instrumental e sensorial de uma composição aromática aplicada na pele em função do ciclo menstrual / Study of instrumental and sensory correlation of a aromatic composition on the skin in function of mentrual cycle

A área de perfumaria no mundo vem se desenvolvendo a cada dia buscando maior conhecimento das matérias-primas aromáticas, desde suas reações, estabilidade até suas interações com o substrato onde é aplicado, sempre em busca do conhecimento de todas as variáveis que possam influenciar a relação perfume-substrato e a aceitação dos consumidores, medida por meio da avaliação sensorial. Apesar de muitos estudos sobre a relação perfume-pele, poucos envolveram a relação com ciclo menstrual. Neste estudo o objetivo foi correlacionar às análises sensorial e instrumental (medidas biomecânicas e cromatográficas), estudar as matérias-primas aromáticas em função do ciclo menstrual. O estudo envolveu indivíduos com idade entre 18-40 anos: 29 mulheres e 3 homens, estes usados como grupo controle. Cada voluntária teve 40 µl da composição aromática Ciclo 1910 aplicado no antebraço, onde foram feitas as medidas biomecânicas (corneometria, sebumetria e TEWL) nos tempos inicial e 6h. Nos tempos inicial, 1.5h, 3h, 4,5h e 6h se auto-avaliaram sensorialmente a intensidade de perfume por meio de escala sensorial de magnitude rotulada (LMS) e foram coletados os compostos aromáticos liberados pela técnica de headspace e analisados por espectrometria com cromatografia a gás e detetor de massa (CGMS). Realizou-se também medidas biomecânicas de corneometria, sebumetria e TEWL interescapulares em 5 voluntárias nos tempos inicial e 6h para comparação. Os resultados obtidos foram que as fases do ciclo não interferiram nas variáveis biomecânicas (p>0,05) quando analisadas isoladamente. Para as medidas realizadas no antebraço, os índices de Corneometria (p<0,001) e TEWL (p: 0,011) na região tratada apresentou média maior que a do controle. A média dos índices de Corneometria e Sebumetria da região do antebraço tratada foi menor (p<0,001) que da região interescapular. Na análise cromatográfica não houve um padrão de resposta em diferentes fases do ciclo. As correlações entre a avaliação sensorial e instrumental (cromatografia e propriedades biomecânicas) não observaram nenhum nível de correlação (p>0,05). A Cromatografia (dados cromatográficos) foi maior na fase Folicular que nas fases Menstrual e Ovulatória (p=0,003), ao considerar como variável resposta em função do ciclo menstrual e da avaliação sensorial. Houve uma forte correlação positiva entre a análise sensorial e a avaliação na pele do homem (p<0,001). No entanto, o fator intrínseco do indivíduo Mulher influenciou na resposta, ocasionando grande variabilidade, porém percebeu-se claramente que os hormônios sexuais interferiram na resposta sensorial, cromatográfica e biomecânica da pele

The perfumery in the world has been developed everyday bringing more knowledge about aromatic raw-materials, as from chemistry reactions, stability until their interactions with substrate where is applied, always looking for variables could influence in the relation perfume-substrate and consumer acceptability, measured by sensory evaluation. Despite a lot of studies were done on this subject, few involved effects as function of menstrual cycle. The aim of this study was to correlate sensory and instrumental analysis (biomechanical and chromatographic measurements), to study the olfactory profile of raw materials in function of menstrual cycle. The study involved people with 18-40 years old: 29 volunteers, three men, who were used as control group. Each volunteer had 40 µl of perfume applied on forearm, where were done Biomechanical measurements (Corneometer, Sebumeter and TEWL) at initial and 6h, At time initial, 1.5h, 3h, 4.5h and 6h; they did self-sensory assessment in perfume intensity in own forearm using labeled magnitude scale (LMS) and also where aromatic compounds released were collected by headspace technique spectrometry and gas chromatography with mass detector (CGMS). In addition, it was done biomechanical measurements (Corneometer, Sebumeter and TEWL) on interscapular region at initial and 6h for comparing. Resulting that the phases of the cycle did not affect the biomechanical variables (p > 0.05) when analyzed individually. For measurements in the forearm, Corneometry index (p < 0.001) and TEWL (p=0.011) in the treated area were higher than the control. The average of the Sebumetry, Corneometry indexes of the forearm treated was lower (p <0.001) than the interscapular region. In the analysis of chromatographic, there was a standard response at different stages of the menstrual cycle, however the analysis by individual had no a pattern response to the release of aromatic compounds. The correlations between sensory and instrumental (chromatography and biomechanical properties) did not observe any correlation (p> 0.05). But when considering chromatography as the response variable as a function of the menstrual cycle and the sensory evaluation, the follicular phase was higher than the Menstrual and Ovulatory phase (p=0.003). There was a strong positive correlation between sensory analysis and evaluation on men skin (p<0.001). However, the intrinsic factor of the individual woman influenced the response, leading to large response variability; however, see clearly that sex hormones interfere in the sensory response, chromatographic and biomechanics of the skin

Camphor--a fumigant during the Black Death and a coveted fragrant wood in ancient Egypt and Babylon--a review.

The fragrant camphor tree (Cinnamomum camphora) and its products, such as camphor oil, have been coveted since ancient times. Having a rich history of traditional use, it was particularly used as a fumigant during the era of the Black Death and considered as a valuable ingredient in both perfume and embalming fluid. Camphor has been widely used as a fragrance in cosmetics, as a food flavourant, as a common ingredient in household cleaners, as well as in topically applied analgesics and rubefacients for the treatment of minor muscle aches and pains. Camphor, traditionally obtained through the distillation of the wood of the camphor tree, is a major essential oil component of many aromatic plant species, as it is biosynthetically synthesised; it can also be chemically synthesised using mainly turpentine as a starting material. Camphor exhibits a number of biological properties such as insecticidal, antimicrobial, antiviral, anticoccidial, anti-nociceptive, anticancer and antitussive activities, in addition to its use as a skin penetration enhancer. However, camphor is a very toxic substance and numerous cases of camphor poisoning have been documented. This review briefly summarises the uses and synthesis of camphor and discusses the biological properties and toxicity of this valuable molecule.

Role of perfumes in pathogenesis of autism.

Autism spectrum disorders (ASDs) are developmental conditions characterized by deficits in social interaction, verbal and nonverbal communication, and obsessive/stereotyped patterns of behavior. Although there is no reliable neurophysiological marker associated with ASDs, dysfunction of the parieto-frontal mirror neuron system and underdeveloped olfactory bulb (OB) has been associated with the disorder. It has been reported that the number of children who have ASD has increased considerably since the early 1990 s. In developed countries, it is now reported that 1-1.5% of children have ASD, and in the US it is estimated that one in 88 children suffer from ASD. Currently, there is no known cause for ASD. During the last three decades, the most commonly accepted paradigm about autism is that it is a genetically inherited disease. The recent trio analyses, in which both biological parents and the autistic child's exomes are sequenced, do not support this paradigm. On the other hand, the environmental factors that may induce genetic mutations in vitro have not been clearly identified, and there is little irrefutable evidence that pesticides, water born chemicals, or food preservatives play critical roles in inducing the genetic mutations associated with known intellectual deficiencies that have been linked to autism spectrum disorder (ASD). Here, we hypothesize and provide scientific evidence that ASD is the result of exposure to perfumes and cosmetics. The highly mutagenic, neurotoxic, and neuromodulatory chemicals found in perfumes are often overlooked and ignored as a result of a giant loophole in the Federal Fair Packaging and Labeling Act of 1973, which explicitly exempts fragrance producers from having to disclose perfume ingredients on product labels. We hypothesize that perfumes and cosmetics may be important factors in the pathogenesis of ASD. Synthetic perfumes have gained global utility not only as perfumes but also as essential chemicals in detergents, cosmetics, soap, and a wide variety of commonly used items, even in food flavoring to enhance product taste. Here we provide evidence that a majority of perfumes are highly mutagenic at femtomolar concentrations, and cause significant neuromodulations in human neuroblastoma cells at extremely low levels of concentration, levels that are expected to reach a developing fetal brain if the pregnant mothers are exposed to these chemicals.

Multicentre patch testing with a resol resin based on phenol and formaldehyde.

BACKGROUND: Contact allergy to phenol-formaldehyde resins (PFRs) based on phenol and formaldehyde is not detected by a p-tertiary-butylphenol-formaldehyde resin (PTBP-FR) included in most baseline patch test series. OBJECTIVES: To investigate the rate of contact allergy to PFR-2 (a mixture of monomers and dimers from a resol resin based on phenol and formaldehyde) in a Swedish population, and to investigate associated simultaneous allergic reactions. METHODS: Five centres representing the Swedish Contact Dermatitis Research Group included PFR-2 in their patch test baseline series for a period of 1.5 years. RESULTS: Of 2504 patients tested, 27 (1.1%) reacted to PFR-2. Of those 27 individuals, 2 had a positive reaction to formaldehyde and 2 to PTBP-FR. Simultaneous allergic reactions were noted to colophonium in 6, to Myroxylon pereirae in 14, and to fragrance mix I in 15. CONCLUSIONS: The contact allergy frequency in the tested population (1.1%) merits its inclusion in the Swedish baseline series and possibly also in other baseline series. Simultaneous allergic reactions were noted to colophonium, M. pereirae, and fragrance mix I.