Abstract
BACKGROUND:
Occupational skin disease (OSD) is a common health issue in the food processing sector. However, risk factors for OSD are suspected to differ according to the nature of the operation.
OBJECTIVE:
To ascertain if the risk factors for OSD vary depending on the type of food processing operation, namely meat processing vs. a commercial bakery.
METHODS:
Participants were asked to answer questions regarding workplace exposures and the current skin condition of their hands. Bivariate analyses were conducted to identify differences between the two participating operations.
RESULTS:
The meat processing workers were more likely to have wet work exposure, used hand sanitizer more often and changed their gloves more frequently. These findings from meat processing represented a statistically significant difference compared to the commercial bakery workers. Also, workers from meat processing reported more severe skin symptoms.
CONCLUSIONS:
Risk factors for OSD apparently differ between types of food processing operations. Differences in the nature of skin symptoms were also found between the two participating operations. It is therefore suggested that future studies examining OSD within the food processing sector should evaluate this health effect based on the nature of operations rather than the sector as a whole.
Introduction
Occupational skin disease is a common work-rel-ated disorder and is so debilitating in some individuals that it results in significant morbidity as well as lost earning potential [1, 2]. Studies have found that the risk of contact dermatitis, the most common type of occupational skin disease [3], is greater in food processing operations than other types of workplaces [4, 5]. This is worth noting as the food processing sector is a huge industry that employs a large workforce. Specifically, in Canada, it is the second largest manufacturing sector and the largest manufacturing employer with nearly 250,000 workers 1
The elevated risk for skin problems in the food processing sector has been attributed to a variety of activities including frequent hand washing, exposure to cleaning agents e.g. soaps and detergents as well as contact with food ingredients that may be allergens or irritants [5, 6]. Furthermore, some of the common contact allergens in food processing are rubber components from gloves, spices and food protein, while common contact urticants are animal and plant proteins [7].
It is speculated that risk factors for occupational skin disease may vary between operations as known risk factors such as moisture, allergens and cold temperature [8, 9] may not be found in all food processing facilities or found to the same degree. However, to the best of our knowledge, no study has evaluated if there are indeed differences in risk factors between types of food manufacturing operations. Assuming that there are indeed differences, awareness of the associated risk factors can assist in the development of targeted prevention strategies for each type of operation. In addition, it is important to recognize the dissimilarities, if any, in the nature of the skin symptoms according to the type of food processing operation. Collectively, this information is critical in order to reduce the frequency and severity of occupational skin disease within this industry sector. Therefore, the objective of this exploratory study was to ascertain if risk factors for occupational skin disease differ between a meat processing and a commercial baking facility - the two most common types of food processing operations in the province of Ontario, Canada 2 .
Methods
This was a cross-sectional study design and Ryerson University’s Research Ethics Board approved the protocol.
Workplace and participant recruitment
One of our team members (CF) had a contact database of food processing operations (i.e. former and current clients, professional acquaintances), in the Greater Toronto Area and, from this database, one meat processing facility and one commercial bakery were invited and agreed to participate (100%response rate). The participating meat processing facility prepares toppings for pizza such as pepperoni, ham and salami. The participating commercial bakery is an artisan bakery that makes bread (loaves and buns), pastries and pizza dough. Both operations have less than 100 employees each.
Workers were invited to complete the study questionnaire on the date of the research team’s on-site visit (convenience sampling). Invitees included those who handle the finished products such as production workers, packaging workers and those in maintenance as well as shipping and receiving. Individuals who wished to participate were initially asked to sign a written consent form and, subsequently, given a copy of the questionnaire to complete. Members of the research team were available to assist with clarification of any questions as well as the proper use of the self-assessment screening tool.
Questionnaire design
A self-administered questionnaire was created to collect demographic and workplace exposure information. The majority of the survey questions were adapted from the Nordic Occupational Skin Questionnaire (NOSQ-2002 Long Form) [10]. Individuals were asked a series of questions related to skin symptoms and whether their symptoms were worse at work or improved when away from work. A subject was considered to have “skin symptoms” if they reported any of the following: itching, burning, redness, dry skin (scaling/flaking), cracks, wheals and hives. Respondents were also asked to rate the current skin condition of their hands based on the screening tool developed by Nichol et al. [11]. Self-rating of hands could be classified as normal, mild or moderate/severe skin changes. “Mild” skin changes meant that a small part of the hands had minor dryness or redness. “Moderate/severe” skin changes meant larger areas of the hand had minor dryness or redness or small areas of the skin had severe dryness and/or redness or a large portion of the hands had scaling, fissures, crusts or scabs, vesicles and/or papules [11]. “Mild” and “moderate/severe” changes were considered “abnormal” for the purposes of analysis.
Workplace exposure to water, soap, detergents, food, plants, chemicals, dusts, degreaser, as well as glove usage, hand wash frequency and hand sanitizer use were self-reported by participants. A respondent was considered to be a “wet worker” if they indicated they worked with their hands in water for 2 + hrs per shift, or used gloves for 2 + hrs per shift or washed their hands more than 20 times per shift [12].
Data analysis
Survey results were described using frequency distributions. Differences between workers in the bakery and meat processing facility were investigated using either Chi-square test or Fisher’s exact test (when the cell sample size was < 5). When analyzing differences between groups related to symptom severity, the denominator used was the number of individuals who reported having skin symptoms on their hands in the past 12 months. All statistical analyses were performed using TIBCO Spotfire S + 8.2 (Palo Alto, CA).
Results
Participant characteristics
Forty individuals from the meat processing facility participated in the study (response rate of 40/41 or 98%), while 25 workers participated from the bakery (response rate of 25/26 or 96%). Not all questions were answered by every participant and, therefore, the total number of respondents differed between questions. Participants were generally male, over the age of forty, worked full-time and had been working in the food processing sector for more than five years (Table 1). In addition, many of the respondents were involved directly with food production (41%) and the majority (68%) spent more than six hours per day performing their main task.
Characteristics of study participants, stratified by type of operation
Characteristics of study participants, stratified by type of operation
*Respondents were asked to indicate if they have ever been diagnosed with allergy, asthma, dermatitis and/or eczema. 1Three non-responders, 2 four non-responders, 3 one non-responder. A “Production” workers were those directly involved with food processing, B “support” workers lent assistance to the operations such as maintenance and shipping/receiving, C “packaging” workers were responsible for placing the prepared products onto trays or containers and wrapping/sealing in preparation for shipment.
There were a number of significant differences with respect to workplace exposures and risk factors. Workers from the meat processing facility were more likely to have wet work exposure (85%vs. 32%, p < 0.001), including wearing gloves for greater than two hours per shift (65%vs. 20%, p = 0.001) and tended to wash their hands more than 20 times per shift (38%vs. 16%, p = 0.091). Participants from meat processing also changed their gloves (70%vs. 10%, p < 0.001) and used hand sanitizer more frequently (51%vs. 0%, p < 0.001) (Table 2).
Workplace exposures and risk factors, stratified by type of operation
Workplace exposures and risk factors, stratified by type of operation
1 Six non-responders, 2 11 non-responders, 3 12 non-responders, 4 four non-responders, 5 eight non-responders and three don’t knows, 6 one non-responder, 7 six non-responders and one don’t know, 8 three non-responders and two don’t knows, 9 five non-responders, 10 seven non-responders and four don’t knows.
As shown in Table 3, 17 (26%) respondents reported that they currently suffer from skin symptoms. In comparison, when using the self-assessment tool, 19 (29%) respondents indicated “abnormal” skin with a larger proportion of workers from the meat processing facility reporting this condition (38%vs. 16%). In addition, those in meat processing were more likely to report that their symptoms were more severe (a score of more than 5 on a scale of 1 to 10, with 10 being extremely bad symptoms) (83%vs. 17%, p = 0.393) as well as indicate that their skin symptoms improved when away from work (93%vs. 7%, p = 0.002).
Respondents’ reported skin symptoms including self-assessment of current condition of hands, stratified by type of operation
Respondents’ reported skin symptoms including self-assessment of current condition of hands, stratified by type of operation
*Symptoms included itching, burning, redness, dry skin (scaling/flaking), cracks, wheals and hives. ** Scale: 0 = no symptoms, 10 = extremely bad symptoms.
Respondents who had wet work exposures tended to self-report symptoms that were of higher severity at their worst (24%vs. 9%, p = 0.082) and these symptoms reportedly improved when the worker was away from work (54%vs. 18%, p = 0.069) (not shown). Of note, workers from the commercial bakery were more likely to be exposed to dust (91%vs. 16%, p < 0.001) but this risk factor was not found to be significant in the reporting of skin conditions (p = 0.860).
Among workers who reported skin symptoms in the last 12 months (n = 25), workers with “abnormal” skin were more likely to indicate that something at work made their skin conditions worse than those with “normal” skin (100%vs. 0%, p = 0.162). Fur-thermore, among workers who reported skin symptoms in the last 12 months, those workers that are currently symptomatic did not experience symptoms until their current position (29%vs. 50%, p = 0.633) (not shown).
Discussion
The results of this exploratory study suggest that risk factors for occupational skin disease do differ between meat processing and commercial baking–the two most prevalent types of food processing operations in Ontario, Canada 3 . Both wet work and frequent hand washing (20 + times per shift) are known to lead to skin symptoms [12–15]. There was a statistically significant difference in wet work exposure between workers at the two participating operations resulting in more workers from meat processing self- reporting that their skin was “abnormal” i.e. mild or severe skin conditions according to the assessment tool. Furthermore, those participants from meat processing were more likely to use hand sanitizer than workers in the commercial bakery. Alcohol-based products can cause dryness and skin irritation [16], though they are less irritating than washing hands with soap and water.
Studies have concluded that glove usage may lead to the development of occupational skin disease [17, 18]. We found a statistically significant difference in glove usage in terms of duration of use as well as change frequency between workers at the two participating operations. Meat processing workers tended to wear gloves for more than two hours on their work shift and, therefore, are more likely to report having “abnormal” skin. It bears mentioning that certain ingredients used to make gloves such as natural rubber latex and rubber accelerators are known to cause both urticaria and contact dermatitis [19]; however, we did not document the type of gloves that were used at the participating operations.
Another statistically significant difference in exposure between the two operations was related to dust. The workers in the bakery were more likely to be exposed to dust than workers from the meat processing facility. Studies have reported that dust exposure among bakers is known to cause occupational skin disease [20, 21]. However, we found no associations between this risk factor and reported skin symptoms from the participating commercial bakery. This finding warrants further examination in a future study.
The prevalence of reported skin symptoms was common in the current study (26%); however, there was a higher proportion in meat processing (30%) compared to those from the bakery (20%). Interestingly, the reported frequency of symptoms from those working in the commercial bakery in the current study was nearly identical to the frequency (19%) for a similar operation based in Scotland [14]. Among symptomatic respondents, a larger percentage of the workers from the meat processing facility indicated that their skin symptoms were worse at work and were more severe. To our knowledge, this is a novel finding of the study. Further, a larger percentage of the symptomatic workers from the meat processing facility (93%) indicated that their symptoms tended to improve when away from work. Although this phenomenon of skin symptoms improving when not at work has been noted previously [14], we believe that we are the first to report that this differs by the type of food manufacturing operation.
Despite experiencing skin symptoms, many individuals likely remain at their current job due to fear of losing their job or face the prospect of changing careers and having to re-train [22]. In fact, Zack et al. found that workers with skin symptoms wanted to continue working in their present job and expressed a desire to gain awareness of prevention strategies [22]. A common prevention strategy, training, has been demonstrated to be successful in curbing the frequency and severity of occupational skin disease among food processing workers in the past [23]. New knowledge gained from this study that risk factors for occupational skin disease vary depending on the type of operation suggests that training and other prevention strategies ought to be operation-specific.
A limitation of this study was that we only examined one meat processing facility and one commercial bakery. Despite the small sample size, we were able to discern differences between the two types of operations. In addition, the information collected was self-reported by workers and the condition of their hands was self-assessed and not verified. Another limitation is that, we did not ascertain if any of the risk factors examined worsened hand symptoms.
Conclusion
In conclusion, this exploratory study found that risk factors for occupational skin disease differs between the two most common type of food manufacturing operations - meat processing and commercial bakery. There were also apparent differences in the nature of skin symptoms between workers at the two participating operations. Future similar studies are suggested with an increase in the sample size, expanding to other types of food processing operations and to examine other risk factors including the impact of temperature extremes as both hot and cold temperatures are known to result in skin symptoms [13].
Footnotes
Acknowledgments
The authors wish to thank the sites and all individuals who agreed to participate in this study. We also would like to recognize the contributions of Jasmayr Hujan, Dina Abusitta, and Mansurkhan Pathan of the School of Occupational and Public Health at Ryerson University.
Conflict of interest
The authors have no conflicts to declare.
Funding
This study was generously funded by the Centre for Research Expertise in Occupational Disease (CREOD).
