Health hazards caused by laser printers and copiers

Abstract

Laser printers and copiers are suspected to emit toner dust and volatile organic compounds and thereby to represent a health hazard. This article summarizes the present state of knowledge about emissions of laser printers and copiers and the present quality standards. There are no data showing an excess exposure of consumers working with laser printers and copiers to inhalable fine dust and volatile organic compounds. Toxicity studies show that toners consist of low-toxicity poorly soluble particles. In experimental animals, accumulation of toner particles in the lung following long-term inhalation exposure to high toner concentrations may cause chronic inflammation and lung fibrosis. Chronic in vivo inhalation studies with rats and hamsters did not show increased lung tumor rates. However, intratracheal instillation of very high toner doses produced significantly increased lung tumor rates in rats. Since there is no significant exposure of consumers to toners using copiers and laser printers these effects are unlikely to occur in humans. Case reports show that inhalation exposure to toner may be associated with symptoms of the upper and lower airways in sensitive subjects. Presumably, these symptoms are related to individual hypersensitivity reactions. Most of these reports suffer from severe shortcomings (inadequate documentation of medical history and exposure; inadequate evaluation of causal relationships).

Full text

Translation of: Ewers, U.; Nowak, D.: Gesundheitsschäden und Erkrankungen durch
Emissionen aus Laserdruckern und Kopiergeräten? Gefahrstoffe − Reinhalt. Luft 66 (2006)
no. 5, p. 203-210
Health hazards caused by emissions of laser printers and copiers?
U. Ewers, D. Nowak
Abstract
Laser printers and copiers are suspected to emit toner dust and volatile organic compounds and
thereby to represent a health hazard. This article summarizes the present state of knowledge
about emissions of laser printers and copiers and the present quality standards. There are no
data showing an excess exposure of consumers working with laser printers and copiers to
inhalable fine dust and volatile organic compounds. Toxicity studies show that toners consist of
low-toxicity poorly soluble particles. In experimental animals, accumulation of toner particles in
the lung following long-term inhalation exposure to high toner concentrations may cause chronic
inflammation and lung fibrosis. Chronic in vivo inhalation studies with rats and hamsters did not
show increased lung tumor rates. However, intratracheal instillation of very high toner doses
produced significantly increased lung tumor rates in rats. Since there is no significant exposure
of consumers to toners using copiers and laser printers these effects are unlikely to occur in
humans. Case reports show that inhalation exposure to toner may be associated with symptoms
of the upper and lower airways in sensitive subjects. Presumably, these symptoms are related
to individual hypersensitivity reactions. Most of these reports suffer from severe shortcomings
(inadequate documentation of medical history and exposure; inadequate evaluation of causal
relationships).
Authors:
Professor Dr. rer. nat. Ulrich Ewers,
Hygiene-Institut des Ruhrgebiets, Abteilung für Umweltmedizin und Umwelttoxikologie
(Hygiene-Institute in the Ruhr area, Department for Environmental Medicine and
Environmental), Gelsenkirchen, Germany,
Prof. Dr. med. Dennis Nowak, Institut und Poliklinik für Arbeits- und Umweltmedizin der Ludwig-
Maximilians-Universität (Institute and Outptient Clinic for Occupational and Environmental
Medicine, Ludwig-Maximilians-University), Munich, Germany.
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1 Introduction
Personal computers, printers, copiers and fax machines are part of the everyday environment of
thousands and millions of people. They are used in numerous offices, laboratories and industry
workplaces, in shops and hotels, in medical practices and schools as well as in many private
households. Thus the question whether harmful substances are released when operating these
devices and to what extent they are released is an important issue of public interest since
millions of people worldwide would be affected.
In Germany in particular, a public debate on the release of harmful substances from office
devices has developed. The question uppermost in mind is whether operating laser printers
and copiers emit toner dust and volatile organic compounds (VOC) and whether this leads to
an exposure of office workers and consumers to harmful substances. Test and computer
magazines as well as TV programmes have repeatedly been reporting “alarming” test results
and have produced a feeling of insecurity in many consumers.
Among the health effects associated with operating laser printers are persistent rhinitis, sore
throat, cough, asthma as well as inflammations of the eye or skin. Moreover, it has been
claimed that toners may be carcinogenic and may cause inflammations [1; 2].
To make the discussion more objective, comments and information brochures have been
published by different institutions, e.g. Bundesanstalt für Arbeitsmedizin and Arbeitsschutz
(BAuA, Federal Institute for Occupational Safety and Health) [3], Bundesinstitut für Risikobe-
wertung (BfR, Federal Institute for Risk Assessment) [4; 5], Umweltbundesamt (Federal
Environmental Agency) [6], Hauptverband der gewerblichen Berufsgenossenschaften (HVBG)
and Berufsgenossenschaftliches Institut für Arbeitsschutz − BGIA (Federation of Institutions for
Statutory Accident Insurance and Prevention and BG-Institute for Occupational Safety and
Health) [7], Berufsgenossenschaft Druck und Papierverarbeitung, and Verwaltungs-Berufs-
genossenschaft (Institutions for Statutory Accident Insurance and Prevention in the Printing and
Paper Processing Industry, and in the Administrative Sector) [8] as well as various other
institutions [9 to 11].
The objective of the present article is to summarize and evaluate the scientific data on the
effects of laser printer and copier emissions, especially toner dust, on cells and organisms.
Furthermore, cases of illnesses reported in medical literature that are attributed to exposure to
toners are critically discussed.
2 Material emission from laser printers and copiers
Laser printers and copiers can emit small amounts of dust, volatile organic compounds (VOC)
and ozone [11 to 17].
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In contrast to older devices where the imaging drum is electrostatically charged with a corona
wire, modern laser printers and copiers emit considerably smaller amounts of ozone as most of
them usually employ the transfer-roller-technology. With this technology, practically no ozone is
generated. Ozone filters are not necessary for these devices.
Dust emitted by laser printers and copiers may consist of paper dust as well as of toner dust.
Due to physical and technical reasons, a significant release of toner dust from laser printers and
copiers during printing is not to be expected since the toner dust is released from the closed
toner cartridge via a very narrow slit. This slit is very close to the surface of the passing, electro-
statically charged paper. The toner particles are attracted by the electrostatically charged paper
and can therefore not be emitted. After the toner has been fused and fixed in the fuser and after
the excess toner has been wiped off, toner dust cannot be emitted from the printed paper.
Toners consist of very small particles of a thermoplastic polymer, usually a styrene-acrylate
copolymer, that are fixed on the paper by fusing. The toner is heated up to 170 ºC [12]. Black
toners contain carbon black or iron oxide as pigments. Colour toners contain various organic
pigments. In addition to these main constituents, toners contain various additives such as wax
and silica, partly also small amounts of specific metal salts to control the electromagnetic
properties.
The diameter of toner particles is about 2 to 10 µm. Toner dust belongs to the group of respi-
rable fine particles, which upon inhalation are deposited predominantly in the tracheobronchial
and alveolar region. A minor fraction may also be deposited in the nose, the larynx and the
pharynx.
VOC may be released during the fusing of the toner and during the heating of the paper.
Other sources can be plastic materials and electronic components of printers or copiers. VOC
emissions from these sources, however, usually decrease rapidly within a few days after a new
printer or copier has been installed and operated for the first time. Besides VOC, also semi-
volatile organic compounds (SVOC) such as phenols and cresols, phthalates, phosphorous
esters and siloxanes have to be considered. They are used as plasticizers, flame retardants and
release agents in specific device components and materials and are released into the ambient
air under the influence of heat.
Short-term emissions of toner dust may occur when changing a toner cartridge or when
cleaning or repairing a laser printer or copier. Persons who frequently do this kind of work may
be exposed to toner dust at higher levels. For prevention, these persons should take adequate
precautions so that the inhalation of toner dust is avoided.
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3 Quality standards for laser printers, copiers and toners
According to the award criteria of the environmental label “Blue Angel” [18], the following
requirements apply to printers, copiers and multifunction devices:
• Toners and inks must not contain hazardous substances.
• Regarding the contamination with heavy metals related to manufacturing, the ALARA
principle applies.
• Pigments that can release carcinogenic aromatic amines are not permitted.
• In accordance with a given test method, device emissions are to be determined by a testing
institute qualified for this test and must be presented. Given emission rates for volatile
organic compounds, benzene and styrene in particular, for ozone and for dust must not be
exceeded.
• Out of informative reasons, emission test results for colour devices when printing with a
colour print master must also be presented.
Another ecolabel for environmentally sound and safe printers and toners is the BG-PRÜFZERT-
label with the additions “tested safety, ergonomic, low-emission” and “tested for toxins”
respectively [19; 20], which is awarded by the Testing and Certification Body of the Expert
Committee Administration of the Professional Association of the Administrative Sector. The
criteria defined in the principles for testing refer to device emissions [19] and to harmful
constituents of toners [20].
Emission measurements of laser printers and copiers are conducted according to the ECMA
standard 328 [21]. Based on this standard, the Bundesanstalt für Materialforschung und
-prüfung (BAM, Federal Institute for Materials Research and Testing) has developed a testing
procedure to measure the emissions of hard copy devices [22]. This procedure applies for
devices that are tested for emissions within the scope of the environmental label “Blue Angel”.
In parallel with this procedure, the Berufsgenossenschaftliche Institut für Arbeitsschutz (BGIA,
BG-Institute for Occupational Safety and Health) in cooperation with the Fraunhofer Wilhelm-
Klauditz-Institute (WKI) developed a dynamic test chamber procedure to determine material
emissions from IT work equipment and devices [14]. This test procedure mostly corresponds
with the emission test chamber method that was developed in the 1990ies to characterize and
quantify VOC emissions from building material and from indoor fixtures and commodities.
Product testing is conducted in air-conditioned test chambers under standardized conditions,
with high purity air passing through the chambers. The test procedures specify requirements
with regard to climatic parameters, volume of the test chamber, air exchange rate, duration of
conditioning, ready, printing and follow-up phase, etc. Considering test chamber volume and air
exchange rate, specific emission rates for each device are calculated based on the substance
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concentrations measured in the test chamber air. These emission rates are stated in the units
µg/(device h) or mg/(device h).
The device-specific dust emission rates of today’s laser printers usually are between 0.5 and
2.5 mg/(device h) [23]. Since airborne particles are usually measured by determining the dust
amount intercepted by filters gravimetrically, it is not possible to distinguish between paper dust
and toner dust. With these measurements, it is not possible to quantify the relative fraction of
paper dust and toner dust either.
The maximum emission levels used for awarding the German environmental label “Blue Angel”
are shown in Table 1. The emission levels refer to the printing phase only. They are based on
the guide values of the Indoor Air Hygiene Commission of the German Federal Environmental
Agency and on other values of assessment with a model room according to DIN EN 13 419 [24]
and a use factor of 0.1. According to this use factor, actual printing time is, at most, 10% of the
time of a continuous printing operation theoretically possible in one day. This would correspond
to a printing volume of about 1,000 pages a day for a desktop device with 16 to 17 pages per
minute. When determining the maximum emission rates, it was taken into consideration that the
target values defined for indoor air would not be reached by one single printer only as other
emission sources also contribute to indoor air exposure.
Table 1:
Permitted limit values for the emission rates (SERU) of TVOC, benzene, styrene, ozone
and dust according to award criteria of the environmental label for printers (RAL-UZ 85)
and multifunction devices (RAL-UZ 114) [18].
Substance
SERU
printing phase
(mg/(device h))
SERU
tabletop units
ready mode
(mg/(device h))
SERU
floor-mounted units
ready mode
(mg/(device h))
TVOC 10 1 3
Benzene 0.05
Styrene 1
Ozone 2
Dust 4
The emission rates measured under the defined test conditions are only partly suitable for
calculating the concentrations of dust, VOC and ozone that can occur in a room during the
operation of a laser printer or copier. The reason for this is that these concentrations depend on
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numerous other conditions that can merely be controlled. The measured emission rates are
rather device-specific parameters, which may be used to compare the emissions of various
devices.
The levels of harmful substances in toners measured according to the BG-PRÜFZERT standard
“Toners for Laser Printers and Copiers” [20; 25] cannot be used to predict the emission beha-
viour of printers, copiers and multifunction devices. It is also not possible to predict the indoor air
concentrations of harmful substances in offices and private rooms on the basis of toner ana-
lyses. Nevertheless, the levels of hazardous constituents and impurities in toners should be as
low as possible according to the ALARA principle.
4 In vitro toxicity studies of toners
For in vitro studies, toners and toner extracts are incubated with bacteria cells and mammalian
cells in culture media under qualified conditions. The following in vitro tests were used in
particular:
• studies with bacteria (salmonella typhimurium) to determine mutagenic or genotoxic effects
(Ames test)
• studies with alveolar macrophages from rats and guinea pigs to determine cytotoxic and
inflammatory effects
• studies with fibroblasts.
The results of these studies [26 to 29] do not indicate that toners and toner extracts are cyto-
toxic and mutagenic and that reactive oxygen compounds are produced. For very high toner
concentrations (≥ 10 µg toner dust/106 cells), it has been noted that TNFα (mediator of inflam-
mation) as well as the cytoplasmatic enzyme lactate dehydrogenase (indicator of cell wall
damage) have increasingly been released from alveolar macrophages.
5 In vivo acute toxicity studies of toners
Lin and Mermelstein [30] studied the acute toxicity of 16 Xerox toners in rats and rabbits.
Oral toxicity was tested by administering toner doses of 5 to 35 g/kg body weight (!) to rats
by gavage. Acute inhalation toxicity was tested by exposing the animals for 4 hours to toner
concentrations of 0.17 to 10.29 g/m³. Acute dermal toxicity was tested by administering toner to
the shaven back skin of the rabbits via a patch. According to the test results, there are no indi-
cations of acute oral, inhalative and dermal toxicity of the tested toners. The effect of the test
toner on the eye was also tested within the scope of these studies: Draize eye irritancy tests in
rabbits yielded negative results.
Guinea pig maximization tests did not show any signs of skin sensitization in guinea pigs.
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Data on acute dermal and oral toxicity and on acute inhalation toxicity are given in the material
safety data sheets (MSDS) of different commercially available toners. The inhalative LC50 (rat,
4 hours) is generally stated as > 50 mg/m³, the oral LD50 (rat) as > 2000 mg/kg and the dermal
LD50 (rat and rabbit) as > 2000 mg/kg.
In summary, it can be concluded that toner dust has a very low acute toxicity when administered
by inhalation or by the oral or dermal route of exposure. According to criteria of the EU Directive
67/548/EEC, Annex VI, it is not required to classify toners as toxic or harmful if swallowed, in
contact with skin or by inhalation.
6 Subchronic and chronic inhalation toxicity
Detailed studies in rats and Syrian golden hamsters on subchronic and chronic inhalation
toxicity of toner dust were carried out in the 1980s and 1990s by Muhle, Bellmann,
Creutzenberg et al. at the Fraunhofer Institute of Toxicology and Aerosol Research in Hannover
(Germany). The results of these studies are described in several publications [31 to 35].
All inhalation toxicity studies were carried out with a Xerox test toner specially produced for
these experiments. It contained a larger fraction of respirable particles than commercial toners.
The test toner consisted of a styrene-1-butyl-methacrylate-copolymer. The pigment was high-
purity carbon black with a mass fraction of 10%. The median aerodynamic diameter (MMAD) of
the particles was 4.0 µm. According to the criteria of the American Conference of Governmental
Industrial Hygienists (ACGIH), up to 35% of the test toner consisted of respirable particles. The
fraction of monomeric constituents and other VOC was smaller than 0.1% of weight. Extracts of
the toner as well as extracts of the carbon black used for the production of the toner did not
show any mutagenic activity in the Ames test. Titanium dioxide was used as an inert reference
dust, cytotoxic silica dust of the type DQ12 was used as positive control.
The results of the studies may be summarized as follows:
• Subchronic and chronic inhalation exposure to toner concentrations up to 64 mg/m³ does
not lead to overt and significant toxic effects of a general nature (systemic toxicity).
• In rats, chronic exposure to toner concentrations ≥ 4 mg/m³ leads to an accumulation of
particles in the lung as well as to persistent inflammatory processes and slight to moderate
fibrotic changes in the lungs of rats. In hamsters, these effects were only observed at
significantly higher concentrations (> 20 mg/m³).
• In rats, which are much more sensitive than hamsters, a concentration of 4 mg/m³ can be
regarded as the lowest-observable-effect-level (LOEL).
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• Since chronic exposure to toner concentrations of 1 mg/m³ is not associated with significant
biological effects in rats, this concentration can be regarded as the no-observable-effect-
level (NOEL). In hamsters, concentrations > 6 mg/m³ are the NOEL.
• Neither in rats nor in golden hamsters, an increased lung tumor rate was detected.
The particle accumulation in the lung tissue of the experimental animals is attributed to a
damage and overload of the lung clearance mechanisms and is called “lung overloading”. This
is not an effect specific to toner dust but is generally observed when high concentrations of
other, slightly soluble dusts are inhaled.
Presently, it is not possible to assess if the results obtained for the Xerox test toner, especially
the concentration-response-relationships, can be transferred to other toners or if such a transfer
is acceptable. Nevertheless, the following arguments support the conclusion that other
comparable toners have similar characteristics of toxicity:
• The toners nowadays in use consist of polymer particles of similar particle size distribution
and similar specific gravity.
• The biological effects produced by the inhalation of toner dust are primarily related to
particle properties (insolubility and persistence in the biological environment; particle size
distribution, specific gravity). In contrast, the chemical composition of the polymer matrix, of
the employed pigment and of other ingredients as well as the presence of impurities caused
by manufacturing seem to be of no relevance.
• Presently, it is not possible to assess if and to what extent particle surface properties can
evoke biological effects.
7 Biological effects after intratracheal instillation of toners
Möller et al. [29] report on a study in which 3 mg of a commercially available black toner
(suspended in a physiological saline solution) was instilled in the trachea of rats. At the same
time, the Xerox test toner was analysed which had been used in the in vivo inhalation study. A
bronchoalveolar lavage was conducted 7 days after the instillation. Different biochemical and
cellular parameters were measured in the bronchoalveolar lavage fluid. Compared to the
control, a distinct inflammatory response was verified. Both toners only differed slightly.
Within the scope of a detailed study, Pott and Roller [36] analysed 19 granular bio-durable
particles without any known essential specific toxicity (GBP) regarding their carcinogenic effect
in rats. The particles were administered to female Wistar rats (age 8 to 10 weeks) as a suspen-
sion by means of intratracheal instillation in weekly intervals. The animals were then observed
over their entire lifetime and the number of animals with lung tumors was determined.
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Among the examined dusts in this study was the Xerox test toner, which had been tested and
evaluated as non-carcinogenic in the in vivo inhalation experiments of Muhle, Bellmann,
Creutzenberg, et al. [31 to 35].
The toner dust was administered by intratracheal instillation directly into the lung of the experi-
mental animals in 10 or 20 single doses of 6 mg each per animal. The applied total doses were
about 400 and 800 mg/kg of body weight (!) respectively. The examination showed that a large
number of the experimental animals developed primary lung tumors. Details can be gathered
from the research report [36], which has only been published on the internet so far.
8 Experiences and studies in human beings
Descriptions and characterizations of adverse health effects and diseases connected with toner
dust mostly exist in form of non-assessable lay reports and press articles which are primarily
published on the internet. So far, there have only been a small number of well-founded, medical
examination reports and scientific examinations that are available to experts. Most of the case
studies published in scientific literature suffer from inadequate or totally missing exposure
estimations while medical histories of basic diseases and pre-damages of concerned people
have only insufficiently been established.
Lin and Mermelstein [30] report on the results of a study during which 16 different Xerox toners
were administered to the skin of 100 test subjects (patch test). No skin irritations or sensitization
reactions on the skin were detected.
Rabe and Haase [37; 38] tested biopsy specimens of 18 persons who declared to be especially
sensitive to toner dust with the so-called “Alergocell” method. It is reported that the biopsy speci-
mens of these persons showed “obvious mast cell and/or eosinophil degranulations, i.e. positive
reactions in different dimensions” when being tested with the “patient-specific toner and/or with
single toner stimulation solutions”. The results of this examination are insufficiently documented
and cannot be assessed as the validity of the test method is disputed.
Gallardo et al. [39] described the case history of a 44-year-old woman who slightly smoked
cigarettes and had worked in a copy shop for 6 years. A slight lung fibrosis was determined in
the transbronchial lung biopsy specimen, which had been extracted thoracoscopically. Iron and
silicon could be detected both in the toner and in the lung biopsies. The authors concluded that
the female patient suffered from a siderosilicosis. However, this is difficult to understand as
a) exposure is not clear, b) iron and silicon can also be found in healthy lungs, c) (semi)
quantitative specifications are missing, d) details on the amount of iron and silicon in control
subjects are missing.
Armbruster et al. [40] described a 39-year-old non-smoker with a granulomatous pneumonitis
and mediastinal lymphadenopathy, who had worked in a newspaper agency for 18 months. The
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histological examination of the lung and lymph-node biopsy specimens resulted in non-necrotiz-
ing granulomas with epitheloid cells and giant cells. Besides, the X-ray energy dispersive micro-
analysis of the toner dust as well as the lung and lymph-node biopsy specimens showed copper
peaks, leading the authors to the diagnosis of granulomatous pneumonitis and mediastinal
lymphadenopathy due to photocopier emissions. For the same reason as described for Gallardo
et al. [39], this casuistic description is also doubtful in its causal-analytical assessment. Maybe
the man suffered from a sarcoidosis.
In an epidemiological study, Rybicki et al. [41] found a significantly increased odds ratio of 1.74
(95 CI 1.23-2.46) for the existence of sarcoidosis if the interviewed persons “had ever used a
photocopier”. The odds ratio of persons who had ever exchanged toner cartridges or who had
been employed in photocopier maintenance services was 2.88 (1.83-4.54). Sarcoidosis is an
inflammatory general disease which causes formation of microscopically small connective tissue
nodes, so called granulomas, which are formed in the whole body and impair the particular
organ functions. In most cases, the lymph-nodes are swollen. The lung is concerned in almost
all cases. It is unknown what causes this disease. An aetiological connection with dust exposure
is not known. It is therefore very doubtful if a causal relationship between toner dust exposure
and increased sarcoidosis risk can be assumed.
At present, the relationship between the use of toners and adverse health effects is examined in
a pilot study financed by the BfR [5]. In a first step, the study conducted by Prof. Dr. V. Mersch-
Sundermann of the Institute for Indoor Air and Environmental Toxicology of the University of
Gießen is supposed to provide information whether the operation of laser printers and copiers
can influence indoor air in a way that damages health.
A connection between an increased internal exposure to harmful substances and the intensive
use of copiers and laser printers could not have been demonstrated yet, according to a study of
Einsiedler et al. [42]. The authors conducted a human-biological monitoring study concerning 11
metals and solvent constituents contained in toners with male and female employees of offices
and copy shops. An excessive exposure of the organism to heavy metals and solvent consti-
tuents beyond the general background exposure could not be detected.
9 Diseases caused by toners?
According to a press release of the Bundesinstitut für Risikobewertung (BfR, Federal Institute
of Risk Assessment) [5], 72 notifications of adverse health effects attributed to toners were
registered between the year 2000 and March 2005 by the “Poison and Product Documentation
Centre”. Symptoms mostly reported are running noses, irritations of the conjunctiva and
pharyngeal mucosa as well as asthma-like cough. The attending physicians attribute the
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symptoms to exposure to toners. It is not documented whether and to what extent a careful
clarification of the causal relationship was conducted in these cases.
In “Cases of Poisoning Reported by Physicians in 2002” [43], “an allergic rhinitis and obstructive
respiratory disease caused by toner dust from laser printers and copiers” is reported for a 48-
year-old patient, which was recognized as an occupationally related disease. After printers and
copiers had been installed at his workplace, the patient increasingly had infections of the upper
and lower respiratory tract, breathing difficulties, cough and paranasal sinusitis. In November
1990, bronchial asthma was diagnosed. A nasal provocation test with toner dust led to an
immediate reaction of the nasal mucosa with sternutation, coryza, swollen nasal mucosa and
limited nasal breathing. Besides, the patient had bronchial symptoms like cough and increased
production of sputum and dyspnea. The symptoms last for 4 days. There was a selective
increase of eosinophil leukocytes in the differential blood count which was interpreted as an
indication of an allergic reaction. When contact with laser printers and copiers was avoided,
discomfort was relieved. As the devices and rooms where the affected person had worked were
not cleaned and maintained properly, “the extraordinary exposure to toner dust at the work-
place” was regarded as “the exclusive reason for the existing allergy”.
The Berufsgenossenschaften (Institutions for Statutory Accident Insurance and Prevention for
Trade and Industry) have recognized three cases of illness in connection with exposure to toner
dust as occupational disease so far. For reasons of data protection, the occupational medicine
evaluations of these cases cannot be discussed in detail. Generally, it has to be noted however
that not every disease developed at work can be defined as an occupational disease. An occu-
pational disease is rather restricted to specific conditions: According to §9 (SGB, German Social
Security Code VII), occupational diseases are diseases insured persons suffer from after exe-
cuting an activity that is covered by the insurance (acc. to §2, 3 or 6 of SGB VII). The German
Federal Government defines those diseases as occupational diseases that according to findings
of the medical science are caused by specific influences, which a particular group of persons is
much more exposed to due to their insured activity than the general population. Moreover, acci-
dent insurance institutions have to recognize a disease as an occupational disease even if it is
not defined in statutory regulation or does not fulfil the requirements stated therein. This is
provided that, according to the latest findings of medical science, the requirements for a
definition according to paragraph 1, sentence 2 (definition of occupational disease, see above)
are fulfilled at the time of the decision.
Positive evaluations of correlation the authors know of have basically two severe deficiencies:
On the one hand, the exposure situation is described insufficiently. If, as mentioned above,
there is almost no release of toner dust during printing operation because of physical and tech-
nical reasons, then it has to be proven at first that exposure to toner emissions as required
according to accident insurance law is given at all for office work. The authors know nothing
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about such evidence ever having been provided at all. On the other hand, the provocation tests
with toner dust conducted by some experts for sick office employees are hardly reasonable as
they do not reflect real exposure situations in the least and do not follow the relevant recom-
mendations of scientific medical societies [44; 45].
If there are obstructive respiratory diseases connected with a distinct unspecific hypersensitivity,
deterioration due to inhalation of toner dust is imaginable under extremely unfavourable – rather
historic – conditions. An objectification is difficult [46]. Longitudinal lung function measurements
with and without exposure would be helpful to assess single cases. If possible, we conduct
provocation tests that simulate workplace situations and place the sick persons in a test
chamber together with the office devices in question. With intensive printer operation (high
degree of black page coverage, if applicable cheap recycling paper), we then examine whether
the unspecific respiratory sensitivity, which is determined before and after the exposure,
changes significantly compared to a control day. So far, none of the exposure tests have shown
a positive result.
According to the existing findings, it can be excluded that interstitial lung diseases can be
caused by exposure to emissions from copiers and laser printers.
10 Summary and evaluation
Toners consist of very small particles of thermoplastic polymers, by which pigments are bound.
The particle diameter ranges from 2 to 10 µm with a median of ca. 5 µm. Toners are to be
classified as fine dust (analogue PM 10) but not as nano-particles.
Polymer particles are not soluble in aqueous solutions and for this reason inert in biological
solutions and textures. They are biologically inert to a large extent. Their toxicity is to be cate-
gorized as marginal. Therefore, toners can be classified as belonging to the group of “granular
bio-durable particles without known significant specific toxicity” (GBP). These kinds of dusts are
called “low toxicity poorly soluble particles” (LTPSP) in Anglo-American literature.
As animal experiments show, long-term inhalation of high toner concentrations (>> 1 mg/m3)
can lead to an overload of the lung clearance mechanisms and to an accumulation of toner
particles in the lung. This can cause inflammatory processes and increased formation of
connective tissue (fibrotic changes). As the use of laser printers and copiers is not linked with a
relevant inhalation exposure to toners, these kinds of effects are not to be expected in connec-
tion with the use of laser printers and copiers.
Long-term inhalation studies in rats and golden hamsters do not indicate a carcinogenic potency
of toners. However, lung tumours were induced in rats after intratracheal instillation of large
amounts of toner (400 to 800 mg/kg body weight). Probably, this is a high-dose effect on the
basis of a massive chronic inflammation which does not occur with small doses. Thus, a linear
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extrapolation of dose-response-relationships to small doses is not reasonable. Moreover, the
question arises whether the rat lung is an adequate model to prove the carcinogenicity of bio-
inert, non-toxic dusts [47]. As lung tumours cannot be induced by exposing mice and hamsters
with comparable dust doses, it can be assumed that the rat lung is an especially sensitive
model.
So far, there have been no scientifically established indications that the operation of modern
laser printers and copiers in offices and households leads to an increased health-relevant
exposure caused by toners and VOC. Human biomonitoring examinations did not indicate an
increased internal exposure to harmful substances for persons who work intensively with laser
printers and copiers.
No convincing evidence has been provided for allergenic effects of toners so far. The above
mentioned case studies indicate that people with an existing, in most cases elsewhere
developed unspecific nasal or bronchial hypersensitivity can develop symptoms like sternu-
tation, rhinitis, cough and/or whistling breathing and rhonchus when inhaling even small
amounts of toner. It is unlikely if these are indeed specific allergic reactions. Supposably, it is an
unspecific hypersensitivity that can also occur when inhaling other dusts. A precise clarification
is only possible when provocation tests are used that are conducted according to the guidelines
of the scientific medical societies [44; 45].
Reports on occupational diseases in connection with toner suffer from methodological weak-
nesses (insufficient documentation of medical history and exposure; inadequate examination
and evaluation of the causal relationship between occupational influence and disease symp-
toms) which are so severe that they are not convincing when critically examined.
Literature
[1] Krank durch Toner – Gefahr für Millionen Menschen. Ed.: Interessengemeinschaft
Tonergeschädigter (ITG) im Bundesverband Bürgerinitiativen Umweltschutz (BBU).
www.krank-durch-toner.de/
[2] Feinstaubbelastung in Innenräumen − Interessengemeinschaft der Tonergeschädigten im
BBU warnt: Toner von Laserdruckern und Kopiergeräten können schwer krank machen.
Ed.: Bundesverband Bürgerinitiativen Umweltschutz (BBU), Bonn. www.bbu-
online.de/presseerklaerungen/prmitteilungen/PR%202005/ 07.04.05.htm
[3] Sicherer Umgang mit Tonerstäuben. Kopiergeräte und Drucker im Büro. Ed.:
Bundesanstalt für Arbeitsschutz und Arbeitsmedizin (BAuA), Dortmund. www.baua.de,
Rubrik Informationen für die Praxis > Publikationen > Faltblätter und Informations-
broschüren.
- 13 -

[4] Können Toner die Gesundheit beeinträchtigen? Pressemitteilung 13/2005 vom 6. Mai
2005. Ed.: Bundesinstitut für Risikobewertung (BfR), Berlin.
www.bfr.bund.de/cms5w/sixcms/detail.php/6327
[5] Gesundheitsgefährdung durch Toner. Ergänzte Stellungnahme Nr. 017/2005 vom 2. März
2005. Hrsg.: Bundesinstitut für Risikobewertung (BfR), Berlin.
www.bfr.bund.de/cm/252/gesundheitsgefaehrdung_durch_toner.pdf
[6] Mit Tonerkartuschen richtig umgehen − Gesundheitsrisiko durch Tonerstaub kann bei
modernen Laserdruckern, Fax- und Kopiergeräten vermieden werden. Umweltbundesamt
Pressemitteilung 17/2001.
[7] Aktuelle Informationen aus dem BGIA. Archiv. Ed.: Berufsgenossenschaftliches Institut für
Arbeitsschutz − BGIA, Sankt Augustin. www.hvbg.de/d/bia/akt/index.html
[8] Berufsgenossenschaft Druck- und Papierverarbeitung: Drucker und Kopierer.
www.bgdp.de/pages/arbeitsicherheit/grundinfo/bildschirmarbeit/tft-2004-3-S19.htm.
Verwaltungs-Berufsgenossenschaft: Laserdrucker sicher betreiben (BGI 820).
Schriftenreihe Prävention 2.3 BGI 820 (2003).
[9] Emissionen aus Laserdruckern. Ed.: Landesgewerbeanstalt Bayern (LGA), Nürnberg.
www.lga.de/de/aktuelles/veroeffentlichungen_emissionen_laserdrucker.shtml
[10] Stichwort Drucker und Computerzubehör. Ed.: Bundesverband für Umweltberatung.
www.beschaffung-info.de
[11] Drucker, Kopier- und Multikfunktionsgeräte – Sicherheit, Gesundheit und Umwelt. Ed.:
Bundesverband Informationswirtschaft, Telekommunikation und neue Medien e. V.
(BITKOM). In Zusammenarbeit mit Verwaltungs-Berufsgenossenschaft und Fach-
ausschuss Verwaltung, Mainz 2002.
[12] Hohensee, H.; Flowerday, U.; Overdick, J.: Zum Emissionsverhalten von
Farbkopiergeräten und Farblaserdruckern. die BG (2000) no. 11, p. 1-4.
[13] Nies, E.; H. Blome, H.; Brüggemann-Prieshoff, H.: Charakterisierung von Farbtonern und
Emissionen aus Farbkopierern/Farblaserdruckern. Gefahrstoffe – Reinhalt. Luft 60 (2000)
no. 11/12, p. 435-441.
[14] Möller, A.; Wensing, M.; Pflaumbaum, W.; Blome, H.: Untersuchung von Emissionen aus
Bürogeräten. Gefahrstoffe – Reinhalt. Luft 63 (2003) no. 3, p. 71-77.
[15] Möller, A.; Wensing, M.; Pflaumbaum, W.; Kießling, M.; Bednarek, M.; Schwarz, A.;
Blome, H.: Erprobung eines Prüfkammerverfahrens zur Messung der werkstoffbedingten
Emissionen aus Arbeitsmitteln der Informationstechnik. Gefahrstoffe – Reinhalt. Luft 64
(2004) no. 3, p. 103-110.
[16] Smola, T.; Georg, H.; Hohensee, H.: Gesundheitsgefahren durch Laserdrucker?
Ergebnisse des VBG-BIA-Projekts „Schwarz-Weiß-Laserdrucker“. Gefahrstoffe – Reinhalt.
Luft 62 (2002) no. 7/8, p. 295-301.
- 14 -

[17] Jungnickel, F.; Kubina, A.; Fischer, H.: Benzolemissionen aus Laserdruckern und
Kopierern. Gefahrstoffe – Reinhalt. Luft 63 (2003) no. 5, p. 193-196.
[18] Der Blaue Engel. Grundlagen für Prüfzeichenvergabe Drucker (RAL-UZ 62), Kopierer
(RAL-UZ 85) und Multifunktionsgeräte (RAL-UZ 114). Ed.: RAL Deutsches Institut für
Gütesicherung und Kennzeichnung, Sankt Augustin. www.blauer-engel.de
[19] BG-PRÜFZERT − Das Berufsgenossenschaftliche Prüf- und Zertifizierungs-system.
www.hvbg.de/d/bgp/index.html
[20] Grundsätze für die Prüfung und Zertifizierung von Tonerpulver für Laserdrucker und
Kopiergeräte (BG VW SG2 04). Ausg. 12/2004. Ed.: Fachausschuss Verwaltung,
Hamburg. www.hvbg.de/d/bgp/prod/pruef/pdf/bg-vw-sg2-04.pdf
[21] Standard ECMA-328: Detection and measurement of chemical emissions from electronic
equipment. August 2001. European Computer Manufacturer Association (ECMA).
www.ecma-international.org/publications/files/ECMA-ST/Ecma-328.pdf
[22] Prüfverfahren für die Bestimmung von Emissionen aus Hardcopygeräten im Rahmen der
Umweltzeichenvergabe für Bürogeräte nach RAL-UZ 62, RAL-UZ 85 und RAL-UZ 114.
Hrsg.: Bundesanstalt für Materialprüfung, Berlin (2003).
[23] Jann, O.; Rockstroh, J.; Wilke, O.; Noske, R.; Brödner, D.; Schneider, U.; Horn, W.:
Entwicklung einer Prüfmethode und Untersuchungen zur Begrenzung von Emissionen aus
Druckern und Kopiergeräten im Rahmen der Umweltzeichenvergabe. Forschungsbericht
201 95 311/02. UBA-Texte 71. Ed.: Umweltbundesamt (UBA), Berlin 2003.
[24] DIN EN 13419-1: Bauprodukte – Bestimmung der Emission von flüchtigen organischen
Verbindungen (VOC), Teil 1: Emissionsprüfkammer-Verfahren (1/2003). Berlin: Beuth
2003.
[25] Hahn, J. U.; Blome, H., Hennig, M.; Hohensee, H.; Jungnickel, F.; Kleine, H.; Möller, A.;
Nies, E.: Kriterienkatalog zur Prüfung von Tonerstäuben. Gefahrstoffe – Reinhalt. Luft 64
(2004) no. 1, p. 21-27.
[26] Bruch, J.: Toxikologische in vitro Bewertung von 6 Tonerstäuben im Vektorenmodell
(Meerschweinchen-Makrophagen-Assay). Kurzdarstellung der Ergebnisse für das
Berufsgenossenschaftliche Institut für Arbeitssicherheit – BIA, Sankt Augustin 1999.
[27] Rehn, B.; Rehn, S.; Bruch, J.: Ein neues In-vitro-Prüfkonzept (Vektorenmodell) zum
biologischen Screening und Monitoring der Lungentoxizität von Stäuben. Gefahrstoffe –
Reinhalt. Luft 59 (1999) no. 5, p. 181-188.
[28] Brüggemann-Prieshoff, H.; Gehrke, T.; Pflaumbaum, W.; Nies, E.: Beurteilung der
Toxizität luftgetragener Stoffe am Arbeitsplatz mittels Leuchtbakterien. Teil 1:
Verfahrensentwicklung. Gefahrstoffe – Reinhalt. Luft 62 (2002) no. 5, p. 191-196.
- 15 -

[29] Möller, A.; Muhle, H.; Creutzenberg, O.; Bruch, J.; Rehn, B.; Blome, H.: Biologische
Verfahren zur Abschätzung des Gefährdungspotenzials von Tonerstäuben. Gefahrstoffe –
Reinhalt. Luft 64 (2004) Nr. 1/2, p. 13-20.
[30] Lin, G. H. X.; Mermelstein, R.: Acute toxicity studies of Xerox reprographic toners.
J. Amer. Coll. Toxicol. 13 (1994), p. 2-20.
[31] Bellmann, B.; Muhle, H.; Creutzenberg, O.; Dasenbrock, C.; Kilpper, R.; MacKenzie, J. C.;
Morrow, P.; Mermelstein, R.: Lung clearance and retention of toner, utilizing a tracer
technique during chronic inhalation exposure in rats. Fundam. Appl. Toxicol. 17 (1991),
p. 300-313.
[32] Creutzenberg, O.; Bellmann, B.; Muhle, H. M; Dasenbrock, C.: Lung clearance and
retention of toner, TiO2, and crystalline silica, utilizing a tracer technique during chronic
inhalation exposure in Syrian golden hamsters. Inhal. Toxicol. 10 (1998), p. 731-751.
[33] Muhle, H.; Bellmann, B.; Creutzenberg, O.; Fuhst, R.; Koch, W. E.; Mohr, U.; Takenaka,
S.; Morrow, P.; Kilpper, R.; MacKenzie, J. C.; Mermelstein, R.: Subchronic inhalation
study of toner in rats. Inha. Toxicol. 2 (1990), p. 341-360.
[34] Muhle, H.; Bellmann, B.; Creutzenberg, O.; Dasenbrock, C.; Ernst, H.; Kilpper, R.;
MacKenzie, J. C.; Morrow, P.; Mohr, U.; Takenaka, S.; Muhle, H.; Mermelstein, R.:
Pulmonary response to toner upon chronic inhalation exposure in rats. Fundam. Appl.
Toxicol. 17 (1991), p. 280 - 299.
[35] Muhle, H.; Bellmann, B.; Creutzenberg, O.; Koch, W.; Dasenbrock, C.; Ernst, H.; Mohr, U.;
Morrow, P.; Mermelstein, R.: Pulmonary response to toner, TiO2 and crystalline silica
upon chronic inhalation exposure in Syrian golden hamsters. Inhal. Toxicol. 10 (1998),
p. 699-729.
[36] Pott, F.; Roller, M.: Untersuchungen zur Kanzerogenität granulärer Stäube an Ratten –
Ergebnisse und Interpretationen. Kurzbericht über das Projekt F 1843 der Bundesanstalt
für Arbeitsschutz und Arbeitsmedizin. Dortmund (2003).
www.baua.de/nn_11598/de/Informationen-fuer-die-Praxis/Publikationen/Fachbeitraege-
Forschungsergebnisse/Gd1,xv=lf.pdf
[37] Rabe U.; Haase, D.; Köhnlein, J.: Intoleranzreaktionen auf Tonerstaub. Nachweis mit der
AllergoCell®-Methode. Umweltmed. Forsch. Prax. 7 (2002), p. 214-215.
[38] Rabe, U.; Haase, D.: Tonerstaub – tatsächlich ein Problem? In: Schwarz, M. (ed.):
Berichtsband zum 3. Dierhagener Umwelttag am 12. Mai 2002. Ostseeklinik Dierhagen,
2002.
[39] Gallardo, M.; Romero, P.; Sanchez-Quevedo, M. C.; Lopez-Caballero, J. J.:
Siderosilicosis due to photocopier toner dust. Lancet 344 (1994), p. 412-413.
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- 17 -
[40] Armbruster, C.; Dekan, G.; Hovorka, A.: Granulomatous pneumonitis and mediastinal
lymphadenopathy due to photocopier toner dust. Lancet 348 (1996), p. 690.
[41] Rybicki, B. A.; Amend, K. L.; Maliarik, M. J.; Iannuzzi, M. C.: Photocopier exposure and
risk of sarcoidosis in African-American sibs. Sarcoidosis Vasc. Diffuse Lung Dis. 21
(2004), p. 49-55.
[42] Einsiedler, K.; Hildenbrand, S. L.; Schmahl, F. W.: Belastung des menschlichen
Organismus mit Metallen und Lösungsmitteln durch tonerpulverhaltige Geräte am
Arbeitsplatz. Umweltmed. Forsch. Prax. 8 (2003), p. 218-219.
[43] Ärztliche Mitteilungen bei Vergiftungen nach §16e Chemikaliengesetz 2002. Hrsg.:
Bundesinstitut für Risikobewertung (BfR), Berlin, p. 57 f.
[44] Arbeitsgruppe „Arbeitsbedingte Gefährdungen und Erkrankungen der Lunge und der
Atemwege“: Arbeitsmedizinische Leitlinien der Deutschen Gesellschaft für Arbeitsmedizin
und Umweltmedizin: Arbeitsplatzbezogener Inhalationstest (AIT).
Arbeitsmed. Sozialmed. Umweltmed. 40 (2005) no. 4, p. 260-267. www-dgaum.med.uni-
rostock.de/leitlinien/AIT.pdf
[45] Durchführung bronchialer Provokationstests mit Allergenen. Leitlinien der Deutschen
Gesellschaft Allergologie und klinische Immunologie. www.uni-
duesseldorf.de/WWW/AWMF/ll/061-006.htm
[46] Nowak, D.; Angerer, P.: Begutachtungsprobleme von Atemwegserkrankungen im
Unfallversicherungsrecht. Med. Sach. 99 (2003), p. 59-65.
[47] ILSI (= International Life Sciences Institute), Risk Science Institute: The relevance of the
rat lung response to particle overload for human risk assessment: A workshop consensus
report. Inhal. Toxicol. 12 (2000), p. 1-17.