Recent Research Activities from the EOM Working Groups

Microbial cell wall agents as an occupational hazard.

Organic dusts cause inflammatory reactions in the tissues exposed. The lung and the cells lining the surface of the respiratory tract are a primary target. Many receptors have been shown to react specifically on the presence of microorganisms that are ubiquitous elements in organic dusts. There is a great variability in the individual response to organic dusts. Almost 50% of Caucasians are hyporesponders to LPS exposure, and people with alpha-1-antitrypsin deficiency are hyperresponsive to organic dust exposure. The diseases resulting from organic dust exposures include asthma, allergy, hypersensitivity pneumonitis and toxic pneumonitis (organic dust toxic syndrome). This paper deals with inflammation and the subsequent mechanism of disease as it is encountered in industries with these exposures. Toxicological studies including human experimental exposures and ex vivo studies of cells are described. Cellular reactions are mediated through the attachment of, e.g. LPS and beta (1,3)-D-glucan to lipopolysaccharide binding protein, CD14 and Toll-like receptors. The relation between protein release and the gene activation is described. Furthermore, studies of the individual susceptibility will be reviewed

Sigsgaard T, Bonefeld-Jørgensen EC, Hoffmann HJ, Bønløkke J, Krüger T.

Toxicol Appl Pharmacol. 2005 Sep 1;207(2 Suppl):310-9. Review 

http://www.ncbi.nlm.nih.gov/pubmed/15992841

Are allergen batch differences and the use of double skin prick test important?

Thomsen GFSchlünssen V, Skadhauge LRMalling THSherson DLSigsgaard T

BMC Pulm Med. 2015 Apr 9;15:33. doi: 10.1186/s12890-015-0021-3

Change in airway inflammatory markers in Danish energy plant workers during a working week.

INTRODUCTION:

It is well known that exposure to organic dust can cause adverse respiratory effect. The pathogen-associated molecular patterns (PAMPS) in the organic dust, such as endotoxin from Gram-negative bacteria cell wall and fungal components, can trigger the release of cytokine (e.g. Interleukin 1β (IL-1β)) and chemokine (e.g. Interleukin 8 (IL-8)) from the immune cells in the airways.

OBJECTIVE:

To evaluate the potential inflammatory effects of organic dust exposure in energy plants in Denmark.

MATERIALS AND METHODS:

Nasal lavage (NAL) and exhaled breath condensate (EBC) were sampled at Monday morning (referred to as before work) and again at Thursday afternoon (referred to as after work). NAL IL-8, EBC pH, IL-1β concentration were measured. Personal exposure to endotoxin and dust was calculated from time spent on different tasks and measured average work area exposures.

RESULTS:

Before work, workers from biofuel plants had a higher IL-1β and IL-8 concentration compared to conventional fuel plants (control group). Specifically, the IL-1β level of moderately and most exposed group, and IL-8 level of the least exposed group were higher compared to the control group. The changes of IL-1β, pH and IL-8 during a work week were not significant. Workers with rhinitis had a lower percentage change of IL-8 compared to healthy workers.

CONCLUSIONS:

An increased level of EBC IL-1β in biofuel energy plant workers before work indicated a chronic or sub-chronic inflammation. The percentage change of IL-8 was lower in workers with rhinitis compared to healthy workers

Zheng Y, Schlünssen V, Bønløkke J, Madsen AM, Skov S, Sigsgaard T.

Ann Agric Environ Med. 2014;21(3):534-40. doi: 10.5604/12321966.1120597

http://www.ncbi.nlm.nih.gov/pubmed/25292124

Reducing the health effect of particles from agriculture.

Brunekreef B1, Harrison RM2, Künzli N3, Querol X4, Sutton MA5, Heederik DJ6, Sigsgaard T7.

Lancet Respir Med. 2015 Nov;3(11):831-2. doi: 10.1016/S2213-2600(15)00413-0. Epub 2015 Oct 8.

http://www.ncbi.nlm.nih.gov/pubmed/26454352

Exposure-response analyses for platinum salt-exposed workers and sensitization: A retrospective cohort study among newly exposed workers using routinely collected surveillance data.

Chloroplatinate salts are well-known respiratory sensitizing agents leading to work-related sensitization and allergies in the work environment. No quantitative exposure-response relation has been described for chloroplatinate salts.

We sought to evaluate the quantitative exposure-response relation between occupational chloroplatinate exposure and sensitization.

A retrospective cohort study was conducted using routinely collected health surveillance data and chloroplatinate exposure data. Workers who newly entered work between January 1, 2000, and December 31, 2010, were included, and the relation between measured chloroplatinate exposure and sensitization (as determined by skin prick test responses) was analyzed in more than 1000 refinery workers from 5 refineries for whom a total of more than 1700 personal exposure measurements were available.

A clear exposure-response relation was observed, most strongly for more recent platinum salt exposure. Average or cumulative exposure over the follow-up period was less strongly associated with sensitization risk. The exposure-response relation was modified by smoking and atopy.

 

Indications exist that recent exposure explains the risk of platinum salt sensitization most strongly. The precision of the estimate of the exposure-response relation derived from this data set appears superior to previous epidemiologic studies conducted on platinum salt sensitization and as a result, might have possible utility for the development of preventive strategies.