Farmers' attitudes towards agricultural plastics - Management and disposal, awareness and perceptions of the environmental impacts.

The amount of plastic waste resulting from agricultural practices is increasing and this trend is expected to continue. Although plastics are essential for certain farming tasks, their impact on the environment is becoming a major issue of concern. Mismanaged larger plastics can disintegrate into microplastics and make their way into soils, surface and groundwater sources. Microplastics are extremely persistent and have the potential to facilitate the transfer of contaminants through the environment, potentially affecting terrestrial and aquatic wildlife. A descriptive survey was conducted on a sample of farmers (n = 430) in Ireland to assess their attitudes on agricultural plastic waste management and their awareness and perceptions of the impacts of microplastics and plastics on the environment. This study found that most farmers (88.2%) are concerned about the amount of plastic waste generated by farming activities. Agricultural plastic disposal methods vary and recycling rates mostly depend on the type of plastic, the cost of recycling and access to facilities. Most farmers view agricultural plastics negatively due to their impact on the environment but also because of the monetary and logistical burdens associated with them. Farmers were relatively aware of microplastics (57.5%), but overall more farmers felt they knew more about plastic pollution than microplastic pollution and these issues in aquatic systems. This was also evident when it came to their perception of the risks plastics pose on the environment with more farmers believing that aquatic environments are at greater risk than the terrestrial environments. Future research efforts must focus on plastic and microplastic pollutions in soils to inform policy-makers and to create greater public awareness. In addition to this, several developments are needed in a collective effort by governments, policy-makers and other stakeholders to reduce plastic and microplastic problems in agriculture.

Current patch test results with the European baseline series and extensions to it from the 'European Surveillance System on Contact Allergy' network, 2007-2008.

BACKGROUND: The pattern of contact sensitization to the supposedly most important allergens assembled in the baseline series differs between countries, presumably at least partly because of exposure differences. Objectives. To describe the prevalence of contact sensitization to allergens tested in consecutive patients in the years 2007 and 2008, and to discuss possible differences. METHODS: Data from the 39 departments in 11 European countries comprising the European Surveillance System on Contact Allergy network (www.essca-dc.org) in this period have been pooled and analysed according to common standards. RESULTS: Patch test results with the European baseline series, and country-specific or department-specific additions to it, obtained in 25 181 patients, showed marked international variation. Metals and fragrances are still the most frequent allergens across Europe. Some allergens tested nationally may be useful future additions to the European baseline series, for example methylisothiazolinone, whereas a few long-term components of the European baseline series, namely primin and clioquinol, no longer warrant routine testing. CONCLUSIONS: The present analysis points to 'excess' prevalences of specific contact sensitization in some countries, although interpretation must be cautious if only few, and possibly specialized, centres are representing one country. A comparison as presented may help to target in-depth research into possible causes of 'excess' exposure, and/or consideration of methodological issues, including modifications to the baseline series.

Allergic contact dermatitis caused by a cell phone cover.

We describe a case of contact dermatitis to a phone cover, which was compounded by secondary allergic contact dermatitis to topical creams used. The phone cover was advertised as being composed of silicone only. Patch testing with the cover material confirmed the diagnosis. In addition, there were positive patch test reactions to a number of allergens in the plastics and glues series from Chemotechnique Diagnostics (Malmö, Sweden). The increasing use of phone covers and the multiple positive reactions to chemicals used in plastic manufacture seen in this case suggest that similar allergic reactions may occur more frequently in the future and should be considered in the differential diagnosis of facial dermatitis.

Measurement of CD4+ and CD8+ T-lymphocyte cytokine secretion and gene expression changes in p-phenylenediamine allergic patients and tolerant individuals.

Factors predisposing to individual susceptibility to contact allergic dermatitis are ill defined. This study was designed to characterize the response of allergic and tolerant individuals' T-lymphocytes after exposure to p-phenylenediamine (PPD). Peripheral blood mononuclear cells (PBMCs) from allergic patients proliferated when treated with PPD and Bandrowski's base (BB) and secreted IL-1alpha, -1beta, -4, -5, -6, -8, -10, and -13; IFN-gamma; tumor necrosis factor-alpha; MIP-1alpha/beta; MCP-1 (monocyte chemotactic protein-1); and RANTES. PBMCs from tolerant individuals were stimulated to proliferate only with BB, and they secreted significantly lower levels of Th2 cytokines. Principal component analysis showed that genes are differentially expressed between the patient groups. A network-based analysis of microarray data showed upregulation of T helper type 2 (Th2) gene pathways, including IL-9, in allergic patients, but a regulatory gene profile in tolerant individuals. Real-time PCR confirmed the observed increase in Th2 cytokine gene transcription in allergic patients. Purified CD4+ and CD8+ T cells from allergic patients were stimulated to proliferate and secrete Th2 cytokines following antigen exposure. Only CD4+ T cells from tolerant individuals were stimulated by BB, and levels of Th2 cytokines were 80% lower. The nature of the antigenic determinant stimulating PBMCs and levels of Th2 cytokines, including IL-9, was confirmed in a validation cohort. These studies show increased activity of Th2 cytokines in CD4+ and CD8+ T cells from individuals with allergic contact dermatitis.

Type 1 and type IV hypersensitivity to nickel.

We report a case of type 1 and type IV contact hypersensitivity to nickel. Very few cases of immediate contact urticaria to nickel have been reported. The mechanism behind this is not fully understood, although it has been postulated that nickel may act as a mast cell discharger on a non-immunological basis. Nickel is found in varying concentrations in stainless steels; its biological availability varies depending on the alloy composition. Our patient has adapted her lifestyle to minimize her contact with household appliances containing nickel. If medical or dental treatment using stainless steel equipment is required, we recommend a short course of oral corticosteroids and antihistamines.

Activation of T-cells from allergic patients and volunteers by p-phenylenediamine and Bandrowski's base.

Allergic contact dermatitis is commonly associated with exposure to p-phenylenediamine. The aim of this study was to determine whether p-phenylenediamine (PPD) and/or Bandrowski's base (BB) stimulate T cells from allergic patients and volunteers, and to explore the relationship between T-cell immunogenicity and allergy. Lymphocytes from allergic patients proliferated with PPD and BB (n=8). Lymphocytes from 14/16 non-allergic individuals also proliferated following stimulation, but only with BB; cord blood lymphocytes failed to respond (n=6). Glutathione, which prevented BB formation, but not binding of PPD to cells and serum, did not prevent p-phenylenediamine-specific stimulation of patient lymphocytes. T-cell clones generated from allergic patients were stimulated separately with PPD and BB, while clones from volunteers proliferated with BB alone. Patient and volunteer clones secreted IL-4, IL-5, IL-13, TNF-alpha, MIP-1alpha, MIP-1beta, and RANTES. These data show that activation of T lymphocytes from allergic individuals alone with PPD represents an important discrimination between allergic and non-allergic groups. BB-specific T cells are found in both allergic patients and volunteers, but not in cord blood. Their presence seems to reflect an acquired immune response, which is not translated into an allergic reaction.

Tixocortol pivalate: what is the right concentration?

Tixocortol pivalate (TP) is a good marker for hydrocortisone allergy. The concentration of TP to be included in the standard series for patch testing has been the subject of debate. The objective of this study was to investigate the right concentration of TP to be included in the standard series for patch testing. 3747 consecutive patients with dermatitis were patch tested simultaneously with TP 1% and 0.1% in petrolatum at 9 centres in the UK from August 2004 to December 2005. Statistical analysis of the results was performed using STATISTICA, version 6 software. 41 patients had positive reactions of current or past relevance. 20 were positive for both concentrations, 13 positive only for TP 1% concentration, and 8 positive only for 0.1% concentration. Statistical analysis, using a two-tailed difference in proportions test, did not show a significant difference between the 2 concentrations (P=0.21). There was no statistically significant difference between the 2 concentrations of TP. The number of allergens that can be included in the standard series is limited for practical considerations. When testing for screening purposes, TP 1% is recommended.

Orofacial reaction to methacrylates in dental materials: a clinical report.

This clinical report presents an unusual response of acute gingivostomatitis caused by contact sensitivity to the methacrylate compounds present in a dental restorative material.