Brussels, 25/06/2015 (Agence Europe) - Long-term exposure by consumers to chlorate in food, and particularly in drinking water, is a potential risk to the health of children - especially those with mild or moderate iodine deficiency, since, over time, exposure to chlorate can inhibit the absorption of iodine - but there is no need to revise the tolerable daily intake (TDI), says a scientific opinion published by the European Food Safety Authority (EFSA) on Wednesday 24 June.
Even taking the highest estimated levels of this chemical compound, EFSA scientific experts say it is unlikely that the total intake in a day will exceed the recommended levels for consumers of all ages.
This scientific opinion on the chronic and acute risks for public health linked to dietary exposure to chlorate, including through drinking water, had been sought by the European Commission to inform decisions to be taken in the EU at a time when the Commission and the member states are re-examining the measures in place to limit consumer exposure to chlorate in food.
Water, fruit, vegetables and frozen foods. Drinking water is the main source of chlorate in the diet, contributing up to 60% of chronic exposure for infants. Chlorate may also be present in food following the use of chlorinated water in food processing or in disinfecting food processing equipment. Fruit and vegetables are the categories of food most likely to contain chlorate. And within each category of food, it is the frozen commodities that most often showed the highest levels of chlorate. The levels probably depend on the quantity of chlorate in the chlorinated water used in processing the foods, EFSA states.
Chronic exposure. According to EFSA, the highest estimates of chronic exposure for infants, toddlers and other children (up to the age of ten) are above the tolerable daily intake of 3 micrograms per kilogramme (µg/kg) of body weight per day, set by EFSA. This is a cause for concern for all children with mild or moderate iodine deficiency.
Acute exposure. The EFSA assessment showed that the highest estimates of acute dietary exposure for all age groups were lower than the “safe” daily intake (or acute reference dose) of 36 µg/kg of body weight of chlorate, recommended by EFSA. This acute reference dose was set because a high daily intake of chlorate is potentially toxic for human beings, since it can restrict the capacity of the blood to absorb oxygen and can lead to kidney failure.
EFSA was also asked by the Commission to assess the impact on dietary exposure of implementation to all foods covered by EU legislation of the guideline level recommended by the World Health Organisation (WHO) for chlorate in drinking water (0.7 milligrams per kilogramme). The experts considered that, were 0.7 mg/kg were to be set as the maximum level in food for the evaluation of dietary exposure to chlorate (excluding food products and water containing chlorate above this level), exposure would be reduced only minimally and, consequently, would not affect the potential risk. Under the scenario - in their view, highly unlikely - of chlorate concentrations of 0.7 mg/kg in all foods and in drinking water, they say that dietary exposure would be significantly higher than current levels. They point to gaps in the available data (in part resulting from the limited amount of time they had for the evaluation) in concluding that the effect of scientific uncertainty on the risk assessment is great.
In preparing this scientific opinion, the assessment of risks was carried out by EFSA in close collaboration with the German Federal Risk Assessment Institute (BfR). EFSA points out that it did not examine the impact of chlorate residue on the microbiological safety of food; its experts considered only the toxicological aspects. (Aminata Niang)