Male was considered as a significant risk factor for developing OCD (OR= 6.22; 95% CI = 1.57-24.62). Meding in 2000 reported a different result finding that more females were affected by work-related skin diseases, which are usually presented as hand eczema . This different result might be caused by more male subjects being engaged in the wet process than females in this study. Almost half of the male subjects (48.81%) worked specifically on the wet process, while only 5.07% of total female subjects worked on the same process. The impact of handling wet work on the emergence of OSD and OCD has been well identified in most studies [13,14]
Age was not associated with the development of OSD and OCD in this study. Only 4 out of 14 elderly subjects were diagnosed having OSD and 2 of them with OCD. In contrast, a study by Soebono in 1995 in which most of the OSD occurred in elderly subjects concluded that age was a significant risk factor . Moreover, Luebberding in 2013 assessed the skin barrier functions in female subjects ranging in age 18-80 years which demonstrated a decline in sebum production among the elder population and increased skin surface pH in post-menopause women. The stratum corneum hydration and transepidermal water loss (TEWL) were equal in both younger and older groups. These changes might affect the skin barrier function, thus increasing the risk of skin diseases in the elder population . One of the possible explanations for this difference is that 10 out of 14 elderly subjects (≥61 years) worked only on the dry process. Working only on the dry process showed a lower rate of skin diseases.
History of atopy
History of atopy was not significantly related to the prevalence of OSD in this study, however, it was a significant factor to develop OCD. Atopy was also not a significant risk factor for OSD in the study by Kusbandono conducted in Yogyakarta in1996 . In contrast, A study by Indriani conducted in Surakarta, Indonesia in 2010 among batik manufacturing workers found that history of atopy was a significant factor in developing irritant contact dermatitis (OR=5.37; p=0.001) .
Experimental studies had demonstrated that a past history of atopic dermatitis (AD) enhanced the susceptibility to irritants, and reflected a higher mean base TEWL [17,18]. Atopy increases the tendency of dermal layers to develop an irritation process and also requires a longer time to be healed . Individuals with a history of atopy constantly have a damaged epidermal barrier which would increase the TEWL and ease the penetration of irritants and microorganisms . Whereas for allergic contact dermatitis, most studies suggest a decreasing tendency of contact sensitization in patients with a history of atopy because of Th1-cell down-regulation [21,22,23]. However, some recent studies show that contact sensitization to common allergens, such as nickel, cobalt, thimerosal, and fragrance mix, occurred in patients with AD at least as frequently as in the general population [20,24]. Moreover, a more recent study found the opposite result, showing higher contact sensitization rates in atopic individuals (65.0%) compared to those in non-atopic (57.4%) . A possible explanation might be due to an easier penetration of the allergens caused by the damaged barrier function in patients with AD .
Length of work experience as batik artisan and working duration
Length of work experience was not associated with the development of OSD and OCD. Working duration in this study was a significant risk factor for the emergence of OSD, but not for OCD. This could be due to a longer duration of exposure to hazards (chemical or mechanical), i.e. repetitive friction which increased the prevalence of callus among the workers who worked mainly on the dry process. Long-term and repetitive friction would lead to keratinization hyperactivity of the stratum corneum, thereby thickening and callus will likely occur.
A study conducted among clothing manufacturing employees in Beijing reported that average working hours per day accounted for a significant risk factor for developing OCD . Basically, the development of OCD did not depend merely on the duration of work, since it should depend on the characteristic of exposure during the work, i.e. irritant or sensitizer.
Type of work
The wet process was found as a significant risk factor for developing OSD and OCD in this study while working on all types of processes apparently contributed to OCD development. Wet work had been reported as one of the most important causes of damage to skin barrier function . Hydration would induce alterations in the horny layer, with stratum corneum expansion happening for as much as 3 up to 4 fold. Additionally, a large amount of water becomes collected within the intercellular spaces and disturbed intercellular lipid structure. This hydration of stratum corneum may eventually facilitate the penetration of substances, including those with irritant or sensitizer characteristics, and consequently, ease the occurrence of occupational allergy contact dermatitis (OACD) and occupational irritant contact dermatitis (OICD) .
Work safety standards and the use of personal protective equipment
Personal protective equipment (PPE) was regularly used by 25.2% (n=56) of workers in this study. Appropriate use of PPE is one of the important measures to protect workers from occupational hazards . Statistical analysis in this study, however, showed that inadequate PPE use was not significantly related to the emergence of both OSD and OCD.
Based on direct observations in the workplace, this finding could be due to some damaged protective equipment that was used by the workers. However, different results were shown in Kusbandono’s study in 1996, which found the lack of PPE use was a risk factor for developing OSD in the 3rd and 4th stages of the batik production process . Soebaryo had a similar result showing rejection of PPE use was a significant risk factor to develop OSD (OR: 2.88, CI: 1.33-6.25) .
We further found some conditions that possibly increase the risk of the chemicals affecting subjects’ health, for example, some work activities were done close to where the subjects handled raw materials for eating, thus the chemical splash might potentially contaminate their food. We also observed that certain dyeing materials were bought in a package with no labels, including having no safety label marked as bio-hazard and no mixing instructions to which the workers should refer while handling the high-risk materials.
This study had some limitations in terms of the scope and target population. The study was limited to only batik manufacturing workers in Yogyakarta Province without considering any other batik manufacturing conditions in other regions of the country. Nevertheless, the sample population was obtained from all districts in Yogyakarta, which was designated as the ‘Batik City’ in 2014 by the World Craft Council.