en تخصصي Special پژوهشي Research <div style="text-align: justify;"><span style="font-size:12px;"><span new="" roman="" style="font-family:" times=""><b>Background:</b><b> </b>Lambda-cyhalothrin (LCT) belongs to pyrethroid insecticides, the use of which has increased for pest control. It is essential to study the effects of LCT on the DNA of living organisms to prevent its mutagenic and carcinogenic properties. Currently, there is a lack of information on the effects of LCT on humans. This study examined the cytotoxicity and genotoxicity of LCT insecticides on human dental pulp stem cells (DPSCs).</span><br> <span new="" roman="" style="font-family:" times=""><b>Methods: </b>We examined the cytotoxicity of LCT at serial concentrations of 0.5, 1, 2.5, 5, 10, 25, and 50 &micro;M using an MTT assay. Four concentrations of LCT at 0.5, 1, 25, and 50 &micro;M were selected from the cytotoxicity curve and subjected to a comet assay to assess genotoxicity.</span><br> <span new="" roman="" style="font-family:" times=""><b>Results: </b>The results of the MTT assay showed that LCT inhibited cell proliferation at 1 &micro;M concentration of the 5% formulation, while the other concentrations of LCT at 0.5, 2.5, 5, 10, 25, and 50 &micro;M increased cell proliferation rates by <span style="background:white">10, 1, 4, 20, 59, and 76%</span>, respectively<span style="background:white">.</span> The results of the comet assay provided evidence that the LCT insecticide induced a statistically significant increase in DNA damage in DPSCs at all tested concentrations compared to those of the negative controls (P>0.05).</span><br> <span new="" roman="" style="font-family:" times=""><b><span style="letter-spacing:-.1pt">Conclusion: </span></b>The LCT insecticide was genotoxic to DPSCs but was not cytotoxic at the tested concentrations, except at 1 &mu;M. Instead, it increased cell proliferation. This suggests that LCT may function through an additional mechanism that mimics that of estrogen and may potentially become a candidate as a xenoestrogen.</span></span></div> Comet assay, Cytotoxicity, Dental pulp stem cells, Genotoxicity, Lambda-cyhalothrin, LCT compound 99 105 http://ijt.arakmu.ac.ir/browse.php?a_code=A-10-1221-1&slc_lang=en&sid=1 manal saleh manalcapno@gmail.com 100319475328460016611 100319475328460016611 Yes National Commission for Biotechnology, Department of Biomedical and Animal, Syria Aroub Al-Masri aalmasri69@hotmail.com 100319475328460016612 100319475328460016612 No National Commission for Biotechnology, Department of Biomedical and Animal, Syria Daas Ezzedin 100319475328460016613 100319475328460016613 No Department of Plant Protection, Faculty of Agriculture, Damascus University, Damascus, Syria