Methylisothiazolinone sensitisation in New Zealand is decreasing

BACKGROUND/OBJECTIVES

In the last 10 years methylisothiazolinone (MI) emerged as a global cause of preservative-related ACD. New Zealand has liberal regulations for the MI concentration limit in cosmetic products compared to Europe and Australia. The aim of this study was to evaluate the prevalence of MI sensitisation in New Zealand, explore sources of MI exposure and make recommendations on New Zealand regulations for MI use.

METHODS

This retrospective study included data from patients who underwent patch testing with MI from 2008 to 2021 in a tertiary hospital dermatology clinic and a private dermatology clinic in Auckland, New Zealand. Patient baseline characteristics were recorded along with results of patch testing. Sources of MI exposure were identified from medical records.

RESULTS

Over the study period, 1049 patch tests were performed in 1044 patients. MI was only tested as a stand-alone allergen from 2015; positive reactions to MI increased from 5.3% in 2015 to a peak of 11.9% in 2017 and then decreased to 6.4% in 2021. The most common source of MI exposure was shampoo or conditioner (27.7% of all relevant reactions) followed by occupational exposures to paints, biocides or glue (19.1%).

CONCLUSION

Both sensitisation and ACD to MI appear to be decreasing, likely secondary to changes in product compounding due to stricter concentration limits internationally. We recommend New Zealand adopt lower MI concentration limits for cosmetics to match the limits of Australia and Europe.

North American Contact Dermatitis Group Patch Test Results: 2019-2020

Background: Patch testing is an important diagnostic tool for assessment of allergic contact dermatitis (ACD). Objective: This study documents the North American Contact Dermatitis Group (NACDG) patch testing results from January 1, 2019, to December 31, 2020. Methods: At 13 centers in North America, patients were tested in a standardized manner with a screening series of 80 allergens, and, as indicated, supplemental allergens. Results: Overall, 4121 patients were tested; 2871 (69.7%) had at least 1 positive/allergic patch test reaction and 2095 patients (51.2%) had a primary diagnosis of ACD. The most commonly positive allergens were nickel (18.2%), methylisothiazolinone (MI) (13.8%), fragrance mix (FM) I (12.8%), hydroperoxides of linalool (HPL) (11.1%), and benzisothiazolinone (BIT) (10.4%). Compared with that of 2017-2018, prevalence of top 20 allergens statistically increased for FM I, HPL, BIT, propolis, and hydroperoxides of limonene (3.5%). For the first time, MI positivity did not increase between reporting periods. Approximately one-fifth of patients (20.3%) had ≥1 clinically relevant reaction(s) to allergens/substances not on the NACDG series. Conclusions: The epidemic of MI contact allergy in North America may have reached a plateau. Patch testing using a robust screening series, and supplemental allergens as indicated, is necessary for comprehensive evaluation of ACD.

Effects of slime toy poisoning in children and teenagers

Abstract Objective: The aim of this study was to identify which types of skin reactions are associated with slime toys and which of their ingredients are most frequently involved in cases of poisoning. Data source: Between January and July 2021, articles were selected using PubMed, SciELO, and LILACS databases. The following descriptors were used: (dermatitis OR rash OR eczema OR inflammation) AND slime. Inclusion criteria were articles available in full, in either Portuguese, English, or Spanish, published between January 2000 and July 31, 2021, and articles reporting cases of contact dermatitis or eczema potentially or directly attributed to slime toys. Articles not meeting these criteria and duplicate texts in the databases were excluded. Data synthesis: In total, 65 publications were identified, of which 16 were included in this review. This resulted in a total of 22 children (2 males, 20 females), aged between 4 and 13 years, who were reportedly intoxicated by slime toys, most of these being linked to homemade preparations. Studies reported the occurrence of contact or allergic dermatitis on hands, fingers, nails, forearms, and cheeks. The most allergenic and/or irritant ingredients included liquid detergent and soap. Additionally, patch tests identified positive reactions to methylisothiazolinone and methylchloroisothiazolinone, the preservatives used by chemical industries on preparation of glue, soap, detergents, etc. Conclusions: Although slime toys might be important for improving motor development and parental relationships, homemade slime toy recipes include several allergenic and irritant ingredients which might be exposed to vulnerable children and cause intoxications. Therefore, homemade slime toys preparations should be used cautiously and under the supervision of adults.

Safer and Greener Polymer Demonstrations for STEM Outreach

Polymer demonstrations have become increasingly important within science, technology, engineering, and math education curricula. These demonstrations not only afford the opportunity to introduce students to polymers but also provide an avenue to educate students about the impact polymers have on the planet. Despite the educational value and recreational enjoyment polymer demonstrations can provide, there are serious health and environmental hazards associated with some of the historically common polymer demonstrations that should be addressed. This Perspective describes the benefits and consequences of the historically common polymer "slime" and "silly putty" demonstrations and then details alternatives that can replace them. Finally, a Methods section of healthier and safer polymer demonstrations with detailed protocols is included.

Patch-test results in terms of the recently recommended allergens in children and adolescents: A retrospective cohort study over 22 years from Turkey

BACKGROUND

A European pediatric patch-test series was suggested recently.

OBJECTIVES

To evaluate the patch-test results in children (<10-years-old) and adolescents (10- to 18-years-old) in Turkey, focusing on the clinical/occupational relevance and the diagnostic value of the recently suggested series.

PATIENTS AND METHODS

A retrospective cohort study on 317 consecutively patch-tested patients ≤18 years of age, between 1996 and 2017.

RESULTS

The contact sensitization rate was 46.1%. Allergic contact dermatitis (ACD) was diagnosed in 30.9%, comprising non-occupational (84.7%) and occupational (15.3%) ACD. Nickel was the leading allergen in almost every age group. Methylchloroisothiazolinone/methylisothiazolinone (MCI/MI) was the clinically most relevant allergen, followed by p-phenylenediamine (PPD), ammonium persulfate, fragrance mix I, nickel sulfate, and mercury/mercury(II)amidochloride. Occupational ACD was most frequently seen in hairdresser apprentices (adolescents only) who were sensitized with PPD ± ammonium persulfate. ACD from MCI/MI increased to 5-fold, ammonium persulfate and mercurial compounds to 2-fold, and PPD to 1.7-fold after 2007. Almost one third of patients would be missed by testing only with the recommended allergens.

CONCLUSIONS

For patch testing in Turkish children and adolescents, we suggest additionally testing with ammonium persulfate, mercury/mercury(II)amidochloride, toluenesulfonamide formaldehyde resin, and polyethylene glycol, the latter as a marker for nitrofurazone allergy, in appropriate patients.

Isothiazolinones Common in Children's Toy Slime

BACKGROUND

Contact dermatitis to homemade slime has been frequently reported, with isothiazolinones as a likely sensitizer. Little is known on the presence of these preservatives in commercial, store-bought slime products.

OBJECTIVES

The aims of the study were to review the literature on "slime dermatitis" and to assess for the presence of isothiazolinones in commercially available slime products and homemade slime components.

METHODS

An experimental, colorimetric spot test was used to verify the presence of isothiazolinones in 38 slime products of the 16 best-selling commercial slime kits, 1 finished homemade slime, and 4 common components of homemade slime. High-performance liquid chromatography with UV detection was performed on 8 commercial slime products.

RESULTS

According to the spot test, 27 (71%) of the 38 commercial slime products contained isothiazolinones. High-performance liquid chromatography with UV detection analyses indicated, however, that false-positives and false-negatives readily occur: isothiazolinone content was correctly identified in only 4 (50%) of the 8 samples.

CONCLUSIONS

This study is the first to demonstrate the presence of isothiazolinones in commercial slime toys. Although the colorimetric spot test may have some utility as a screening assay, it is far from specific and likely not sensitive enough to reliably identify methylisothiazolinone.

Pediatric contact dermatitis: what's new

PURPOSE OF REVIEW

Allergic contact dermatitis (ACD) was once thought to be rare in children but recent studies have demonstrated that the prevalence of ACD is common and appears to be increasing in children. Current trends including toys, hobbies, and personal care products may play a role in potentially new allergen exposure or resurgence of certain allergens, making ACD a moving target in children.

RECENT FINDINGS

ACD and atopic dermatitis can coexist and certain clinical features can help differentiate ACD from endogenous atopic dermatitis in children. It is important to consider ACD in children with recalcitrant atopic dermatitis or dermatitis with atypical distribution. Patch testing has become a more common practice in children. In 2018, the first expert consensus-derived pediatric baseline series consisting of 38 allergens was proposed to aid in the diagnosis of ACD in children. Comparing recent patch testing data in the pediatric population, the top allergens ubiquitously identified were nickel, cobalt, neomycin, Myroxylon pereirae (balsam of Peru), fragrance mix I, fragrance mix II, methylisothiazolinone, methylchloroisothiazolinone/ methylisothiazolinone, formaldehyde, and lanolin.

SUMMARY

ACD is a common problem in children. Detection through patch testing, avoidance of offending allergens, and prevention of common allergens are the main focus of management of ACD in children.

Proinflammatory and regulatory mechanisms in allergic contact dermatitis caused by methylchloroisothiazolinone and methylisothiazolinone

BACKGROUND

Methylchloroisothiazolinone (MCI) and methylisothiazolinone (MI) are the cause of an increasing number of contact allergies. Understanding the mechanisms by which MCI/MI induces proinflammatory and regulatory factors production is necessary to understand the outcome of allergic contact dermatitis (ACD).

OBJECTIVES

To evaluate the dysfunction of proinflammatory cytokines and regulatory factors in the positive MCI/MI patch test at the transcriptional and protein expression levels. Moreover, to analyse the cytokines production induced by MI in peripheral blood mononuclear cells (PBMCs).

MATERIALS AND METHODS

The selected patients had positive MCI/MI patch test results. The expression of proinflammatory factors was evaluated by q-PCR and immunochemistry at 48 hours of positive MCI/MI patch test. The MCI/MI- or MI- induced secretion of IL-1β, TNF and IL-6 by PBMC was analysed by flow cytometry.

RESULTS

The results showed a decreased TLR4 expression with upregulated IL6, FOXP3, IL10 and TGFβ mRNA expression as assessed by q-PCR at the site of the MCI/MI skin reaction. We detected increased protein levels of TLR4, FOXP3 and IL-10 in the dermis layer in the ACD reaction by immunocitochemistry. Moreover, MCI/MI induced proinflammatory cytokine production by PBMC through the NF-κB signalling pathway.

CONCLUSION

Considering the altered innate immune response triggered by MCI/MI sensitization, these findings indicate that the regulatory process at the induction phase of ACD is a crucial mechanism. Given the increase in occupational and domestic exposure to MCI/MI, the underlying immunological mechanisms should be understood.

Contact Allergy-Emerging Allergens and Public Health Impact

Contact allergy (sensitisation) and allergic contact dermatitis (ACD) resulting from it have a considerable public health impact. For the present review, all pertinent articles were systematically searched via Medline and Web of Science™; additionally, all available issues of the journals "Contact Dermatitis" and "Dermatitis" were manually searched, covering the years 2018-2019, thereby extending and re-focusing a previous similar review. New allergens, or previously described allergens found in a new exposure context or of other current importance, are described in sections according to substance classes, e.g., metals, preservatives, fragrances. As a common finding in many investigations, a lack of information on product composition has been noted, for instance, regarding a newly described allergen in canvas shoes (dimethylthiocarbamylbenzothiazole sulfide) and, most notably, absence of co-operation from manufacturers of glucose-monitoring devices and insulin pumps, respectively. These latter devices have been shown to cause severe ACD in a considerable number of diabetic patients caused by the liberation of isobornyl acrylate and N,N'-dimethylacrylamide, respectively, as demonstrated by an international collaboration between dermatologists and chemists. Improved and complete ingredient labelling for all types of products, and not just cosmetics, must be put on the legislative agenda.