Safety of gaseous chlorine dioxide as a preservative slowly released in cold food storage areas

Following a request from the European Commission, the EFSA Panel on Food Additives and Nutrient Sources added to Food (ANS) provides a scientific opinion regarding the safety of use of gaseous chlorine dioxide as a preservative that is slowly released in cold food storage areas. Gaseous chlorine dioxide is generated from tubes that contain two reactants, which upon mixing slowly release gaseous chlorine dioxide. The tubes are to be used in cold storage rooms or in refrigerators for domestic use. In consideration of the reactive nature of gaseous chlorine dioxide, the Panel assessed to what extent chlorinated species are generated by the interaction of gaseous chlorine dioxide, under the proposed conditions of use, with some model food matrices. According to the applicant, the only by-products resulting from the proposed use of gaseous chlorine dioxide are chlorite and chlorate; therefore, the safety of these by-products has also been assessed. From the data provided by the applicant, under domestic refrigerator-like experimental conditions, the treatment of model food matrices with gaseous chlorine dioxide led to low amounts of by-products and did not produce chlorinated organic by-products. Chlorate was not detected in the model food matrices tested. Consequently, considering the negligible amounts in model food matrices of the parent compound and of its by-products chlorite and chlorate, together with the available toxicity database, the Panel concluded that, under the domestic refrigerator-like conditions of use proposed by the applicant, the consumption of foods treated with gaseous chlorine dioxide would not be a safety concern. The risk resulting from exposure of the consumer to chlorine dioxide by inhalation was not assessed, because this is outside the remit of the Panel. The Panel considered that a new assessment would be warranted in case of any change in the conditions of use.