Sensitization and Allergy to Enzymes

The prevalence of enzyme sensitization in the(Termamyl ® ) in the industry had been noted
bakeries was 7.8% when all the employees weresince the late 1980s (Sarlo et al 1997). In a later
taken into account and 11.8% in the bakers' group.paper from the same multinational detergent
The prevalence coincides with those reportcompany it was also reported that sensitization to
edelsewhere in Europe, for example, 5-16% in thelipase had been detected in the early 1990s
United Kingdom (Cullinan et al 1994, Smith &(Peters et al 2001).
Smith 1998, Jeffrey et al 1999,Nieuwenhuijsen etIn addition the present study showed that
al 1999), 9% in The Netherlands (Houba et alenzyme allergy is still possible, and it can even
1996), 7.5% in Italy (DeZotti et al 1994), and 19%occur at a high rate, in the detergent industry,
in Germany (Baur1998a).despite the use of encapsulated enzyme
The prevalence of flour sensitization in bakeriespreparations that are principally considered
was12%, which was on about the same order asnondusty and safe. This conclusion received
elsewhere in Europe in the aforementioned studiessupport recently from the study of Cullinan et al
(6%-24%). The employees sensitized to enzymes(2000) in the United Kingdom. The prevalence of
belonged to typical groups exposed to flour andsensitization and clinical allergy in these two studies
enzymes,but a detailed exposure profile was notwas in clear contrast to the prevalencesreported
included in the original study design. Thus furtherby large multinational companies (Cathcart et al
exposure-response assessment was not1997, Schweigert et al 2000, Peters et al 2001).
possible.It was learned that the job tasks ofObviously there are large variations in industrial
many of the sensitized workers had varied overhygiene conditions between different plants.
the years. The study demonstrated thatSmall industries may find it economically difficult to
exposure to powdered additives containingmeet all the standards of the industrial hygiene
enzymes leads to sensitition in Finnish bakers. Inprograms conducted in large companies, including
the rye crisp factory, where exposure was lessperiodic health checks and continuous monitoring
on the whole than in the bakeries, sensitization toof workplace air by immunoassays (Schweigert et
enzymes was rare. Cellulase was shown to causeal 2000,Nicholson et al 2001).
sensitization even at moderate exposure levels.In the enzyme-producing industry, a high rate of
There was a significant association betweensensitization, up to 25%, was noted in subgroups
enzyme sensitization and work-related respiratorywith high levels of exposure.
symptoms.The division into subgroups enabled
However, co-sensitization with flours wasexposure-response (sensitization and respiratory
common, and the origin of the symptoms wassymptoms) calculations, and a statistically
difficult to determine.The animal feed industry is asignificant trend was found for both sensitization
new area of enzyme application. It wasand symptoms. A unique feature was the high
demonstrated that enzymes pose an allergy riskallergy risk of the laboratory personnel. It turned
in this industry,too. The risk is smaller than, forout that powdered enzymes had been handled
example, in the baking industry, but,still, cases ofrather carelessly, and, clearly, an awareness of
occupational asthma due to enzymes havethe sensitizing properties of the cellulolytic
occurred.There was a correlation betweenenzymes was lacking.
sensitization to enzymes and work-relatedIn addition to the sensitization of the employees
symptoms, and some of the sensitized workerswho handled enzymes themselves or worked in
reported symptoms when exposed to enzymes.the vicinity of enzyme handling, some cases of
One of the enzymes to which sensitization wassensitization were found among people not
shown was phytase, which has been developedinvolved directly in production, for example,
solely for use in animal feeding. Previously,among the cleaning and maintenance personnel
sensitization to phytase was found in Finnishand also among office personnel with occasional
enzyme production (study II). These were theexposure. Maintenance workers may be exposed
first reports of allergy caused by this enzyme.to thehighest peak concentrations of enzymes in
In the detergent factory, a surprisingly highthe workplace. The practice of hiring personnel on
prevalence (22%) of symptomatic sensitizationa subcontract basis is becoming general, and this
was found among the process workers.practice increases the probability of being exposed
In addition to established allergens in the industry,to enzymes. The experiences gained in the
the bacterial proteases, sensitization to newsubcontract plant that spray-dried cellulase
enzymes such as lipase and cellulase wasconfirmed the importance of proper and sufficient
detected. This was the first publication on theinformation. The employees in the subcontract
allergenity of these enzymes in the detergentplant were clearly ignorant about the sensitizing
industry. Sensitization to bacterial a amylaseproperties of the substances they were handling.