UV-irradiated 2-methyl-4′-(methylthio)-2-morpholinopropiophenone-containing injection solution produced frameshift mutations in the Ames mutagenicity assay

Mariko Takai, Yoichi Kawasaki, Sakae Arimoto, Yusuke Tanimoto, Yoshihisa Kitamura, Toshiaki Sendo

Research output: Contribution to journalArticle

1 Citation (Scopus)


In previous studies, we detected the photoinitiators 1-hydroxycyclohexyl phenyl ketone (1-HCHPK), methyl 2-benzoylbenzoate (MBB), and 2-methyl-4′-(methylthio)-2-morpholinopropiophenone (MTMP) in intravenous injection solutions. In addition, we reported that 1-HCHPK, MBB, and MTMP exhibited cytotoxicity towards normal human peripheral blood mononuclear cells. A previous in vitro study reported that a free-radical photoinitiator introduced covalently bound purine residues into DNA. However, little is known about the in vitro mutagenicity of 1-HCHPK, MBB, and MTMP. In the present in vitro study, we evaluated the mutagenicity of 1-HCHPK, MBB, and MTMP using the Ames test. We found that untreated 1-HCHPK, MBB, and MTMP were not mutagenic in S. typhimurium strain TA97, TA98, TA100, TA102, or TA1535, regardless of the presence/absence of S9 activation. However, ultraviolet (UV) light-irradiated MTMP exhibited mutagenicity in S. typhimurium strain TA97 in the absence of S9 activation. In conclusion, we suggest that exposure to UV-irradiated MTMP, including in intravenous injection solutions, can result in frameshift mutations.

Original languageEnglish
Pages (from-to)10135-10140
Number of pages6
JournalEnvironmental Science and Pollution Research
Issue number10
Publication statusPublished - Apr 1 2018



  • 2-methyl-4′-(methylthio)-2-morpholinopropiophenone
  • Ames test
  • Frameshift
  • Injection
  • Mutation
  • Photoinitiator
  • UV irradiation

ASJC Scopus subject areas

  • Environmental Chemistry
  • Pollution
  • Health, Toxicology and Mutagenesis

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