Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 215-607-8
CAS number: 1333-82-0
between occupational exposure to chromic acid mist (aqueous chromium
(VI) trioxide) and lung cancer has been concluded. Also, there is
evidence from various case reports and worker studies, that exposure to
Cr(VI) is associated with skin and respiratory sensitiation as well as
eye, skin, and respiratory tract irritation.
addition to the epidemiological studies provided (Sorahan, 1998, 2000
and Kerger, 2009) the studies reviewed in the EU RAR (including those
previously summarised in the UK HSE and IOH reviews) demonstrate an
association between occupational exposure to chromic acid mist (aqueous
chromium (VI) trioxide) and lung cancer. Studies of chrome plating
workers (specifically exposed to chromic acid mists) in the US and UK
show a clear association between exposure and increased mortality from
lung cancer. Studies of occupational exposure to other Cr (VI) compounds
have not shown a similar association. The EU RAR notes that the acidic
and corrosive nature of chromium trioxide may be a significant
contributory factor in the carcinogenesis of chromic acid (aqueous
chromium (VI) trioxide), but that the Cr (VI) ion is likely to be the
toxic moiety. It is considered that there is concern for the human
carcinogenicity of the other water-soluble Cr (VI) compounds in this
group (EU RAR 2005).
Accidental and/or occupational
exposure of humans to Cr (VI) compounds is known to cause skin
irritation which may be severe in nature, particularly following
Animal data are consistent with the
observations made in humans. It is not possible to determine a clear
concentration-response relationship for repeated-exposure human skin
effects from the occupational data available and quantitative data could
be misleading given the potential for severe effects resulting from
repeated contamination of slightly damaged skin.
The EU RAR concluded, based on reports
of accidental occupational exposure, that the highly water soluble Cr
(VI) compounds are skin irritants. Chromium (VI) trioxide is corrosive
as a consequence of its low pH and the development of 'chrome ulcers' in
workers repeatedly exposed to other salts also indicate the potential
for skin corrosivity.
Accidental splashing of highly
water-soluble Cr(VI) compounds in solution into the eye has resulted in
damage to the human eye. A number of case reports have detailed both
inflammation of the cornea and conjunctivae and in more severe cases,
corneal erosion and ulceration.
The EU RAR concluded that, significant
damage to the eye can occur upon accidental exposure to highly
water-soluble Cr (VI) compounds.
Symptoms of sensory irritation of the
respiratory tract are known to occur among chrome plating workers
exposed to a mist of aqueous chromium (VI) trioxide. No quantitative
data on such irritation are available from studies of workers. No
studies reporting symptoms of sensory irritation are available for the
other Cr(VI) compounds. Overall, it is not possible to determine a
reliable concentration-response relationship for respiratory tract
irritation using the available data. Nevertheless, the EU RAR concluded
that, inhaled chromium (VI) trioxide has the potential to cause
respiratory irritation, probably as a consequence of its low pH.
In this case report (Moller, 1986) a
29-year-old male welder reported systemic reactions after exposure to to
chromium vapors from chromium trioxide baths and fumes from steel
welding during both occupational and nonoccupational activities. Inhalation
challenge testing to 29 µg/mg3of sodium chromate aerosol
resulted in late appearing systemic urticaria, angioedema, and severe
bronchospasm that occurred at the same time as a threefold rise in
plasma histamine. A late onset reaction to a chemical known to cause
allergic contact dermatitis and occupational asthma suggested that
immunologic mechanisms could be implicated in this case.
Skin tests and in vitro studies did not
support a role for a classic IgE-mediated response. The possibility that
chromium salts could exert direct histamine releasing effects on
basophils was excluded in vitro but a similar effect on tissue mast
cells was not investigated. The positive direct LlF assay in this
patient suggested that cell-mediated mechanisms may play a role in this
A skin biopsy specimen obtained after
subsidence of most of the angioedema and wheezing demonstrated findings
consistent only with an urticarial eruption, and a specific diagnosis
could not be assigned to the lesion.
This case documents the occurrence of a late
onset anaphylactoid reaction after inhalation of hexavalent chromium
The potential of the water-soluble Cr
(VI) compounds to cause delayed contact hypersensitivity was
investigated in a number of studies in occupationally exposed workers
and in the general population, using patch-testing.
Allergic contact dermatitis (skin
sensitisation) resulting from occupational exposure to water soluble Cr
(VI) compounds is commonly encountered in a number of different groups.
The EU RAR has reviewed a number of published reports of patch testing
in Cr (VI) sensitised humans; the studies report minimum eliciting
concentrations as low as 0.09 µg Cr (VI) /cm². The majority of reported
studies were performed using aqueous solutions of sodium or potassium
dichromate; while similar effects can be assumed for other water-soluble
Cr (VI) compounds, a similar concentration-response relationship cannot
be assumed as this will also be influenced by the extent of dermal
A number of case reports, mainly
within the chrome plating industry, provide evidence that inhaled Cr
(VI) can cause asthma, although the total number of reported cases is
small in relation to the number of workers potentially exposed.
Overall, the available case reports
and evidence from well-conducted bronchial challenge tests, show that
inhalation of Cr (VI) compounds can cause occupational asthma. As with
skin, Cr (VI)- sensitised subjects may react to Cr (III). It is not
possible to determine a no-effect level or exposure-response
relationship for the induction or elicitation of occupational asthma.
Exposure related observations in
humans (repeated dose toxicity)
With respect to repeated exposure, a
large number of studies are available relating to exposure of workers to
highly water-soluble Cr (VI), specifically sodium or potassium
chromate/dichromate and chromium (VI) trioxide. All the human
information on the toxic effects arising from repeated exposure to
highly water soluble Cr (VI) relates to workers in the chromate
production and chromium plating industries. These workers were exposed
to sodium and potassium chromates and dichromates either in solid form
(dusts) or in aqueous solution or to airborne mists of chromium (VI)
trioxide in aqueous solution (chromic acid). Some of the principal toxic
effects produced in these workers reflect the irritant and (at low pH)
corrosive action of Cr (VI) ion toward mucous membranes. Nasal septum
ulceration and perforation, inflammation of the respiratory tract along
much if not all of its length, lung fibrosis, emphysema and chronic
obstructive bronchopneumopathy and inflammation and ulceration of the
gastrointestinal tract from the buccal cavity to the intestines have
been observed. Many of these effects were particularly predominant among
workers in these industries in the past when atmospheric Cr (VI) levels
were probably relatively high. However it is not possible, from the
available information, to relate many of these effects to reliable
measures of Cr (VI) exposure. Although in principle a threshold dose
should be identifiable, in practice the location of such a threshold is
not possible from the data available. There is some evidence that
atrophy of the nasal mucosa occurs in chromium plating workers exposed
to very low average levels (below 0.004 mg/m³ chromium (VI) trioxide,
below 0.002 mg Cr(VI)/m³) in the atmosphere. An important confounding
factor in the development of nasal lesions is the possible transfer of
Cr (VI) in solution from fingers to the nose due to poor personal
Some evidence of kidney damage, such
as proteinuria, has also been found among chromate production and
chromium plating workers. It is noted that kidney damage was also
reported following single exposure. Although in principle a threshold
dose should be identifiable, in practice the location of such a
threshold is not possible from the data available.
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
Questo sito web si avvale di cookie affinché possiate usufruire della migliore esperienza sui nostri siti web.
Welcome to the ECHA website. This site is not fully supported in Internet Explorer 7 (and earlier versions). Please upgrade your Internet Explorer to a newer version.
Do not show this message again