A randomised controlled intervention study on prevention of work related skin problems among gut cleaners in swine slaughterhouses

AIMS

To evaluate the effect of an intervention to reduce work related skin problems in gut cleaning departments in Danish swine slaughterhouses. The intervention consisted of an evidence based prevention programme and a documented method for implementation.

METHODS

Randomised controlled intervention study with a one year follow up. The intervention included educational activities and evidence based recommendations. The effect of the intervention was evaluated by telephone interviews using a standardised questionnaire based on the Nordic Occupational Skin Questionnaire (NOSQ-2002) with modified and additional questions on exposure, preventive measures, information, and discussions on prevention of skin problems, etc.

RESULTS

A total of 644 (87.5%) responded at the baseline interview and 622 (71.6%) at the one year follow up interview. A total of 495 participated in both interviews (67.3%). In the intervention departments the frequency of eczema on hands or forearms within the past three months at follow up was reduced significantly from 56.2% at baseline to 41.0% at follow up, while a slight non-significant increase was observed in the comparison departments (from 45.9% to 50.2%). The intervention activities resulted in more frequent use of protective gloves in general and the use of cotton gloves worn underneath rubber and plastic gloves. At follow up three times as many in the intervention departments used the recommended high fat skin care products introduced as part of the intervention activities. At follow up, discussion of skin problems was increased in the intervention group while no changes were observed in the comparison group.

CONCLUSIONS

A significant 27% relative reduction of occupational eczema in a high risk group was feasible through implementation of an evidence based prevention programme.

Monophthalates promote IL-6 and IL-8 production in the human epithelial cell line A549

The dramatically increasing prevalence of allergic respiratory diseases may in part be due to the presence of certain immunotoxic xenobiotics in the environment. Recent studies have suggested that some plasticizers belonging to the phthalate family, and metabolites thereof, play a role in the development of allergic respiratory diseases. This is probably due to an adjuvant effect, which in some cases may be combined with an inflammatory process. The scope of the present study was to investigate the inflammatory potential of monophthalates, which are degradation products of phthalate plasticizers. The human epithelial cell line A549 was exposed to 15.6-2000 microg/ml, in two-fold dilutions, to either mono-n-butyl phthalate, monobenzyl phthalate, mono-n-octyl phthalate, mono-2-ethylhexyl phthalate, mono-iso-nonyl phthalate or mono-iso-decyl phthalate. Concentrations of the proinflammatory cytokines IL-6 and IL-8 were measured in the cell culture supernatant by ELISA. The study showed that some, but not all, monophthalates could induce a concentration-dependent increase in cytokine production, whereas, at higher concentrations, all phthalates suppressed cytokine production. Both the stimulatory and the suppressive properties were highly dependent on the length of the alkyl side chain of the monophthalate - a structure-activity relationship that is supported by recent observations in mice.

Seasonal variations in T-lymphocyte response to grass pollen allergens from pollen-allergic patients and healthy controls

Previous studies have demonstrated the presence of grass pollen-specific T cells in grass pollen-allergic patients (GPA) as well as nonallergic subjects (NA). In order to elucidate a possible seasonal variation in proliferation and cytokine production of peripheral blood mononuclear cells (PBMC), PBMC from 13 GPA and 11 NA were stimulated with extracts of Phleum pratense and tetanus toxoid before and during two grass pollen seasons. IL-4, IL-5 and interferon-gamma were determined by ELISAs. PBMC from GPA demonstrated a decreased proliferative response to grass pollen allergens during the pollen season as compared to NA (p < 0.05), but no difference was found in the response to tetanus toxoid. Cells from GPA produced higher amounts of IL-4 and IL-5 than NA (p < 0.05) and the seasonal variation in GPA proliferation was paralleled by the grass pollen-induced production of both IL-4 and IL-5 (p < 0.05). We conclude that during the grass pollen season PBMC from GPA have a reduced ability to proliferate and to produce Th2-type cytokines. This may be due to seasonal migration of the grass pollen-specific T cells from the blood to the tissues of primary allergen exposure.

Biomolecular regulation of the IgE immune response III. Cytokine profiles in atopic dermatitis, inhalant allergy and non-allergic donors

Cytokines-in particular interleukin 4 (IL-4), IL-5 and interferon gamma (IFN-gamma)-regulate both IgE synthesis and eosinophil activation in atopic diseases. To elucidate whether distinct profiles of cytokine production were related to serum level of IgE and eosinophilia, the spontaneous and inducible in vitro cytokine secretion from peripheral blood mononuclear cells (PBMC) was investigated. PBMC were isolated and cultured from three groups of donors: (1) patients with atopic dermatitis (AD) and high levels of serum IgE (> 5000 IU/ml, n = 11), (2) patients with diagnosed inhalant allergy (IA) and serum IgE in the range of 200-2000 IU/ml (n = 10), and (3) non-allergic individuals (NA) with serum IgE below 100 IU/ml (n = 10). The production of cytokines was determined in cultures after 24 h [IL-1 alpha, IL-4, IL-5, IL-6, tumour necrosis factor alpha (TNF-alpha), and TNF-beta] or 72 h (IL-2, IFN-gamma). The spontaneous production of IL-1 alpha was increased in the AD group compared to NA (P = 0.002), whereas for unstimulated cultures no other cytokine differed between patient groups. To identify conditions for optimal cytokine production, various combinations of phytohaemagglutinin (PHA), calcium ionophore (ION), and phorbol ester (PMA) were tested as stimuli. The combination ION + PMA induced the highest levels of IL-2, IL-4, IL-5, IFN-gamma and TNF-alpha, whereas maximal production of IL-6 and TNF-beta were induced by PHA and PHA + PMA, respectively. The AD group demonstrated a significantly lower production of TNF-alpha and IFN-gamma compared with the two other groups, and IL-4 and IL-5 production increased in the IA group. The results suggest that in spite of the common features, i.e. raised serum IgE and eosinophilia, in IA and AD patients, the underlying aberrations in the cytokine network is different.