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: 203-396-5
CAS number: 106-42-3
Available data from both in vitro and in
vivo studies indicate that the xylene isomers have no significant
No deviations from vehicle control values,
except for a significantly reduced mutagenic index during the 3rd week
of mating which resulted from an unusually high control value and was
therefore considered not to be treatment-related. No evidence of
decreased pregnancy rate or increased embryo loss.
When the petroleum fraction "mixed xylenes"
was tested in the dominant lethal assay in mice, there was no evidence
xylene isomers and mixed xylenes have been examined for activity on both
gene mutation and cytogenetic endpoints. None
of the xylene isomers was mutagenic in bacterial mutagenicity assays
using Salmonella typhimurium (Haworth, 1983; Bos, 1981; Florin, 1980,
Litton Bionetics, 1978a) or Escherichia coli (Shimizu, 1985) either with
or without the addition of auxiliary metabolic activation systems. Litton
Bionetics (1978a) also reported negative results for gene mutation from
the evaluation of mitotic recombination in Saccharomyces cerevisiae. In
assays examining for chromosomal effects in mammalian cells, mixed
xylene (composition unspecified) did not induce either sister chromatid
exchanges or chromosomal aberrations in Chinese hamster ovary cells
(Anderson, 1990) or gene mutation in mouse lymphoma L5178Y cells (Litton
assay examining the effect of various substances for DNA
in vitro using the alkaline and neutral comet assays (Chen, 2008), the
authors reported increases in DNA
breaks on isolated human peripheral blood lymphocytes exposed to m-, o-
Their investigations suggested that reactive oxygen species may play a
role in the damage observed. The relevance of the small changes possibly
due to active oxygen species observed in isolated lymphocytes is
considered limited. In particular, no evidence to support a consequence
of any radical-induced damage was seen in a cytogenetic assay (Anderson,
1990). In view
of the available studies including the key endpoints of gene mutation
and chromosomal damage, additional in vitro assays of the genotoxicity
potential of xylenes are considered unnecessary.
xylene isomers do not induce micronuclei in the bone marrow of mice
after two intraperitoneal doses in the range 105 – 650 mg/kg b. w.
(Mohtashamipur, 1985). Mixed
xylenes do not induce chromosome aberrations in the bone marrow of
treated rats (0.044, 0.147 and 0.441 mL/kg by intraperitoneal injection,
equivalent to approximately 39, 129 and 388 mg/kg), Litton Bionetics
negative result was obtained for mixed xylenes in dominant lethal assays
conducted in rats and mice (Hine Laboratories Inc., 1973).
data are available regarding the potential genotoxicity of m-xylene,
o-xylene or p-xylene in humans following inhalation, oral or dermal
exposure has been sourced. Limited data is available demonstrating a
lack of genotoxicity of mixed xylenes following inhalation in humans
view of the lack of significant genotoxicity observed in the in vitro
studies, and the available negative results examining for chromosomal
damage in vivo, mixed xylenes and the individual isomers are considered
not to have genotoxic potential.
Justification for selection of
genetic toxicity endpoint
Available data indicate that the
xylene isomers have no significant genotoxicity in bacterial and
mammalian systems in vitro and/or in vivo.
No classification is warranted under CLP
since all xylene isomers show no evidence of genotoxicity in vitro
or in vivo.
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.
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