This study aimed to assess the risk-benefit balance associated to fish consumption by Portuguese preschool children. For this purpose, databases (from IPMA and literature) were mined and mathematically processed by a model based on the Extreme Value Theory assuming consumption scenarios. Eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) and selenium (Se) and methylmercury (MeHg) were selected as critical components of fish, given their health impact and significant contents in some fish species. Assessment also took into account that Se may protect against MeHg toxicity.

With exception of blue shark, Se Health Benefit Value (Se-HBV), was always positive (ranging between 3.3 and 14.9) and Se:MeHg ratio was always higher than one (3.8 to 32.3). It was also estimated that the deleterious effects of MeHg on children IQ were offset by the beneficial impact of EPA+DHA in fish except for grilled black scabbardfish consumed every day. Blue shark, regardless of the culinary treatment, yielded very high probabilities of exceeding MeHg TWI (higher than 84 % with a single weekly meal), thus raising serious concerns. EPA+DHA benefits were high in salmon regardless of culinary treatment (> 84 %). Fish consumption by children is advisable with exception of blue shark and boiled and grilled tuna.

这项研究旨在评估与葡萄牙学龄前儿童食用鱼有关的风险-收益平衡。为了这个目的，数据库（来自IPMA和文献）被开采，并通过基于假设消费情景的极值理论的模型进行数学处理。二十碳五烯酸（EPA）和二十二碳六烯酸（DHA），硒（Se）和甲基汞（MeHg）被选为鱼类的关键成分，因为它们对健康有影响，并且在某些鱼类中含量很高。评估还考虑到Se可以防止MeHg毒性。

除蓝鲨外，Se健康有益价值（Se-HBV）始终为正（介于3.3和14.9之间），Se：MeHg比率始终高于1（3.8至32.3）。据估计，除了每天食用的黑black鱼以外，EPA + DHA对鱼类的有益影响也抵消了甲基汞对儿童智商的有害影响。无论采用何种烹饪方法，蓝鲨都有很高的概率超过MeHg TWI（每周一次进餐超过84％），因此引起了人们的严重关注。无论采用何种烹饪方法，鲑鱼的EPA + DHA益处都很高（> 84％）。除蓝鲨，煮金枪鱼和烤金枪鱼外，建议儿童食用鱼。