Individual symptoms were aggregated into several symptom groups when workers reported at least one of the following symptoms: respiratory symptoms (dry cough, phlegm, wheezing, chest tightness), irritation symptoms (runny eyes, blocking third of nose, runny nose, sore throat, tickling nose or sneeze), gastroenterological symptoms (nausea, lack of appetite, pyrosis), and skin symptoms (skin rash). Symptoms were considered work-related if they were reported by the workers as being provoked or aggravated during their work (question ��Do you experience these symptoms during or shortly after work?��). Data were analyzed using simple and multiple logistic regression analysis. Odds ratios (ORs) with 95% confidence intervals (CIs) not including the value 1 were considered to be statistically significant.

Statistical analyses were performed using SPSS for Windows, v15.0 (SPSS, Inc, Chicago, Ill). Results The distributions of the population characteristics are presented in Table Table1.1. Exposed workers were younger and had a shorter seniority as compared with the non-exposed group. Furthermore, there were more current smokers among the exposed than among the non-exposed workers, whereas non-exposed participants had more frequently stopped smoking or more frequently never smoked than exposed participants. There were also differences in the prevalence of doctor-diagnosed (dd) allergy but not in dd asthma. Finally, more than half of the participating exposed workers did not wear a protective mask..

Table 1 Study population characteristics according to occupational organic dust exposure status, in numbers (percentages between brackets) (unless stated otherwise) Table Table22 shows the prevalence of reported individual symptoms and symptom groups by exposure Entinostat group. All symptom groups and nearly all individual symptoms were more prevalent in the exposed groups. Exposed workers reported significantly more often respiratory, irritation, gastrointestinal, and skin symptoms than the workers in non-exposed group. After adjustment for age and smoking the association between exposure and respiratory, gastrointestinal, and skin symptoms remained statistically significant. Table 2 Prevalence of symptoms (work-related or not) in workers according to organic dust exposure status, in numbers (percentages between brackets) The prevalence of work-related symptom groups by exposure status are summarized in Table Table3.3. All work-related symptoms were significantly more often reported by exposed than non-exposed workers. After adjustment for smoking status and age, the statistically significant associations between exposure and work-related symptoms group persisted.