Evaluation of genotoxic effects of sodium propionate, calcium propionate and potassium propionate on the root meristem cells of Allium cepa S ß ifa Tu ¨ rkog ˘lu * Cumhuriyet University, Faculty of Arts and Science, Department of Biology, Sivas, Turkey Received 11 July 2007; accepted 25 January 2008 Abstract The effects of different treatments with food preservatives, sodium propionate (SP), calcium propionate (CP) and potassium propio- nate (PP), on the cytology and DNA content of Allium cepa were investigated. Five concentrations of these additives – 1000, 1500, 2000, 2500, and 3000 ppm – were applied for 24, 48, and 72 h. All concentrations of these chemicals showed an inhibitory effect on cell division in root-tips of A. cepa and caused a decrease in mitotic index values. Additionally, all treatments changed the frequency of mitotic phases when compared with the control groups. These compounds increased chromosome abnormalities in test material. Among these abnor- malities were C-mitosis, anaphase bridges, micronuclei, binucleated cells, stickiness, laggards, and chromosome breaks. The nuclear DNA contents decreased when compared with control groups. Ó 2008 Elsevier Ltd. All rights reserved. Keywords: Sodium propionate; Potassium propionate; Calcium propionate; Mitosis; Genotoxic effect; DNA content 1. Introduction Food additives are approved for a number of different uses. Some improve the nutritional value of certain foods while others are used to make foods more appealing by improving their taste, texture, consistency or colour. Pre- servatives are food additives which are used to help keep food wholesome and appealing while en route to markets which may be thousands of kilometres away from where the food is grown or produced. Preservatives also help extend the storage life of foods in the home. Propionates are approved preservatives in strictly lim- ited amounts in a range of baked foods. Foods permitted to contain propionates include bread, biscuits, cakes, pas- tries and other flour products (http://www.codexalimentar- ius.net/gsfaonline/additives/details.html?id=370). Sodium propionate, calcium propionate and potassium propionate are sodium, calcium and potassium salts of propionic acid. Calcium propionate is an approved preservative in bread and helps to keep the bread fresh (http://www.nysacs. cornell.edu/fst/fvc/Venture/venture3_chemical.html). Potas- sium propionate and sodium propionate are also approved preservatives (Winter, 1994; Lindsay, 1996). By inhibiting the growth of mould and other microorganisms, propionates allow consumers the convenience of keeping soft, fresh bread in the home without having to purchase it every day. Although both calcium propionate and sodium propionate are equally effective anti-microbial agents, calcium propionate is the form commonly used throughout the world as a preservative in bread produc- tion (http://www.ams.usda.gov/nop/NationalList/TAPRe- views/SodPropionate.pdf). There have been many studies on the genotoxicity and carcinogenicity of several food additives in plants, mice, 0278-6915/$ - see front matter Ó 2008 Elsevier Ltd. All rights reserved. doi:10.1016/j.fct.2008.01.043 Abbreviations: FASEB, Federation of American Societies for Exper- imental Biology; US EPA, US Environmental Protection Agency. * Tel.: +90 346 2191010; fax: +90 346 2191186. E-mail address: turkoglu@cumhuriyet.edu.tr www.elsevier.com/locate/foodchemtox Available online at www.sciencedirect.com Food and Chemical Toxicology 46 (2008) 2035–2041