Seaweed consumption in France: Key data for exposure and risk assessment

Brown seaweed as a food ingredient contributing to an adequate but not excessive amount of iodine in the European diet. A case study with bread

BACKGROUND

The large amounts of iodine in brown seaweeds may contribute towards an adequate iodine intake, but also pose a food safety risk. In the current work we estimate the maximum amount of the cultivated brown seaweeds Saccharina latissima and Alaria esculenta (blanched and non-blanched) that can be added to white loaf-type wheat-bread so European consumers are protected against excessive chronic intakes. We use data for high-level consumers of bread with special ingredients added from the EFSA comprehensive European food consumption database to construct a conservative risk management model. We bake prototype seaweed bread and use the output from the model to assess exposure to iodine and trace metals. We also assess some bread quality parameters such as sensory characteristics, crumb firmness and specific volume.

RESULTS

The maximum level of iodine in bread that would mitigate the European consumer from excess intakes was 857 μg I kg-1 bread. Assuming a typical 60% wheat flour per kilogram of bread, a maximum amount of 11.3 g of dried blanched A. esculenta (115 mg I kg-1 dry weight) could be incorporated per kilogram of wheat flour into the bread recipe whilst for non-blanched S. latissima, which contained 3500 mg I kg-1 dry weight, only a minuscule 350 mg of seaweed was the limit. For prototype breads, seaweed addition had no significant impact on the specific volume and crumb firmness. Levels of cadmium and arsenic in the bread were also of low toxicological concern.

CONCLUSION

A maximum 1-2% brown seaweed of total flour weight could be added to bread to contribute towards European consumers' adequate iodine intake without overexposure. © 2024 The Author(s). Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Dietary exposure and risk assessment to trace elements and iodine in seaweeds

INTRODUCTION

Seaweeds are a rich source of elements such as iodine, and are also able to accumulate contaminants such as trace elements.

METHODS

The aim of this study was to assess the dietary exposure as well as the risk from iodine and trace elements in edible seaweeds for the French population using current consumption data. The contribution of seaweeds to overall dietary exposure to trace elements and iodine was evaluated, and for those substances with minimal contribution to overall dietary exposure, simulations were performed to propose increased maximal limits in seaweeds.

RESULTS

Cadmium, inorganic arsenic and mercury in seaweeds were very low contributors to total dietary exposure to these contaminants (0.7 % 1.1 % and 0.1 % on average, respectively). Dietary exposure to lead via seaweed may contribute up to 3.1 % of total dietary exposure. Dietary consumption of iodine via seaweed may contribute up to 33 % of total exposure to iodine, which makes seaweeds the strongest contributor to iodine in diet.

DISCUSSION

New maximal values in seaweeds are proposed for the very low contributors to total dietary exposure: 1 mg/kg dw for cadmium, 10 mg/kg dw for inorganic arsenic and 0.3 mg/kg dw for mercury.

Probabilistic determination of a maximum acceptable level of contaminant to reduce the risk of overexposure for a novel or emerging food: the case of cadmium in edible seaweed in the French population

European and French populations are overexposed to cadmium (Cd) through their foods. The risk of increased cadmium exposure for consumers needs to be limited by reduced maximum limits (ML) for novel foodstuffs such as edible seaweed in France. The objective was to derive a low and protective cadmium concentration in edible seaweeds to limit cadmium overexposure in consumers. To do so, we applied a probabilistic approach to the data collected on French seaweed consumers, taking into account other sources of exposure for cadmium. This approach led to the identification of a cadmium concentration which should ensure that the seaweed-consuming population does not exceed the tolerable daily intake (TDI) of cadmium according to a probability of cases, when simultaneously exposed to other cadmium dietary sources. Considering the 5% of the population exceeding TDI, the estimated ML is equal to 0.35 mg Cd kg^-1dry matter of seaweed as an unprocessed food with a 95% confidence interval of [0.18,1.09]. The proposed approach is generic and could be applied to other relevant food/substance pairs when considering the setting of MLs in the regulatory system. It ensures better protection of consumer health.