In this study, 92 butter and 100 cream cheese samples were analyzed for aflatoxin M1 (AF M1). They were obtained from retail outlets in five big cities (Istanbul, Izmir, Kayseri, Konya, Tekirdag). The occurrence and concentration range of AF M1 in the samples were investigated by competitive enzyme-linked immunosorbent assay (ELISA) method using immunoaffinity columns. At the detectable level of 10 ppt all 100% of the butter samples and 99% of the cream cheese samples contained AF M1. The incidence of AF M1 in the butter samples and the cream cheese samples ranged from 10 to 7000 ng/kg and from 0 to 4100 ng/kg, respectively. AF M1 levels in 28% of the butter and 18% of the cream cheese samples exceeded the maximum tolerable limit of the Turkish Food Codex. AF M1 levels in the samples show that there is a presence of high aflatoxin level that constitutes a human health risk in Turkey. Therefore farmers and dairy companies need to be informed about the aflatoxin and aflatoxicosis, and also the continuous monitoring of the aflatoxin level must be applied by the Turkish public health authorities. © 2007 Elsevier Ltd. All rights reserved.