Risk Assessment of Ochratoxin A (OTA)

Abstract

Ochratoxin A (OTA) is a mycotoxin produced by fungi of two genera: Penicillium and Aspergillus. OTA is a worldwide spread mycotoxin that contaminates various food commodities and with harmful effects to animals and humans. OTA has been shown to be nephrotoxic, hepatotoxic, teratogenic and immunotoxic to several species of animals and to cause kidney and liver tumours in mice and rats. The genotoxic status of OTA is still controversial because contradictory results were obtained in various microbial and mammalian tests, notably regarding the formation of DNA adducts. In humans, intake of high amount of OTA has been linked to Balkan endemic nephropathy (BEN), a chronic nephropathy described in several rural regions of Bulgaria, Romania, Serbia, Croatia and Bosnia. Risk analysis of a toxicant (such as OTA) is made up of three parts: risk assessment, risk management and risk communication. The risk assessment of the food-borne OTA is the scientific evaluation of its known or potential adverse health effects resulting from human exposure throughout foods. It provides a qualitative and quantitative estimation of the severity and probability of harm resulting from exposure to these hazards. The “hazard” is defined as the intrinsic property of a biological, chemical or physical agent (in this case, OTA) to cause adverse health effects under specific conditions. This definition implies some certainties that, under similar conditions, the agent will cause similar adverse health effects. “Risk” is defined as the estimated probability of an adverse health effect occurring in humans as a result of exposure to a biological, chemical or physical agent in food. Risk assessment involves a complete toxicological assessment, an epidemiological assessment, an exposure assessment and a risk characterization. Two international organizations, the Joint FAO/WHO Expert Committee on Food Additives (JECFA) and the Scientific Committee for Food of the European Commission (SCF) assessed the risk for the human associated with the consumption of foods containing OTA (SCF 1996, 1998; WHO/FAO 1991, 1996, 2001). More recently, a workshop on “Ochratoxin A in Food” organised by the International Life Science Institute Europe in Baden (Hazel and Walker 2005) provided an updated view on the recent research on OTA. This chapter offers a concise review of these different issues and of other new information on OTA risk assessment.