Data for: Uptake of arsenic by irrigated vegetables and cooked food products in Burkina Faso

As compared to the Asian lowlands, environmental exposure to arsenic (As) in West Africa has received little attention. Recent studies have found geogenic As contamination of groundwater in many regions in Burkina Faso. As-contaminated groundwater is used for drinking and increasingly also for the irrigation of staple foods. This study assessesthe extent to which irrigation and cooking of staple foods in Burkina Faso influence plant uptake and dietary consumption of As, respectively. Using a greenhouse experimental setup, we evaluated the transfer of As from irrigation water spiked with 0, 100, 500, and 1,000 μg/L As(V) to the organs and edible parts of seven commonly consumed vegetables (amaranth, carrot, green bean, lettuce, okra, spinach, and tomato). Next, we cooked the greenhouse-cultivated vegetables and externally purchased foods with As-free and As-spiked waters. The As content in all plant organs increased with increasing As in the irrigation water. With 500 μg/L, the concentrations of As in the edible parts (ordered from highest to lowest) were as follows: spinach (6.6 ± 0.5μg/g); lettuce (3.9 ± 0.1μg/g); carrot (3.5 ± <0.1μg/g); amaranth (2.2 ± <0.1μg/g); okra (0.9 ± <0.1μg/g); green bean (0.8 ± <0.1μg/g); and tomato (0.2 ± <0.1μg/g). The edible parts of leafy vegetables irrigated with As-spiked water had a higher average As content (4.9 ± 4.5μg/g) than root (2.9 ± 2.0μg/g) and fruit/pod vegetables (0.8 ± 1.1μg/g). Cooking with an excess volume of As-free water reduced the As content in the cooked vegetables by 39% on average, while cooking with As-contaminated water transferred As to the cooked food. The As content in steamed foods was 8 to 18 times lower than in boiled foods. Based on human health risk estimates, we recommend planting leafy vegetables in areas with low concentrations of As in irrigation water and we propose the maximum As concentrations of 100 μg/L for the cultivation of carrot, and 500 μg/L for green bean, spinach, lettuce, and amaranth. In As-contaminated areas, mitigation strategies include the cultivation of fruit vegetables such as tomato and okra and steaming the food instead of boiling.

相较于亚洲低地地区，西非地区的环境砷（arsenic, As）暴露问题尚未受到足够关注。近期研究发现，布基纳法索多个区域的地下水存在地质源性砷污染。受砷污染的地下水不仅被用于饮用，还日益被用于主食作物的灌溉。本研究旨在评估布基纳法索的主食作物灌溉与烹饪分别在多大程度上影响砷的植物吸收与膳食摄入。本研究采用温室实验装置，评估了分别添加0、100、500和1000 μg/L五价砷（As(V)）的灌溉水中的砷向7种常见食用蔬菜的各器官及可食用部分的迁移情况，涉及的蔬菜包括苋菜、胡萝卜、青豆、生菜、秋葵、菠菜与番茄。随后，研究团队将温室种植的蔬菜与外购食材分别用无砷水和含砷水进行烹饪。实验结果显示，所有植物器官中的砷含量均随灌溉水中砷浓度升高而增加。当灌溉水中砷浓度为500 μg/L时，可食用部分的砷含量从高到低排序如下：菠菜（6.6 ± 0.5 μg/g）、生菜（3.9 ± 0.1 μg/g）、胡萝卜（3.5 ± <0.1 μg/g）、苋菜（2.2 ± <0.1 μg/g）、秋葵（0.9 ± <0.1 μg/g）、青豆（0.8 ± <0.1 μg/g）以及番茄（0.2 ± <0.1 μg/g）。进一步分析表明，用含砷水灌溉的叶菜类可食用部分的平均砷含量（4.9 ± 4.5 μg/g）高于根茎类蔬菜（2.9 ± 2.0 μg/g）与果荚类蔬菜（0.8 ± 1.1 μg/g）。使用过量无砷水烹饪可使蔬菜中的砷含量平均降低39%，而使用含砷水烹饪则会将砷转移至烹制食物中。蒸制食物中的砷含量较水煮食物低8至18倍。基于人体健康风险评估，本研究建议在灌溉水砷浓度较低的区域种植叶菜类蔬菜，并提出胡萝卜种植的最大允许砷浓度为100 μg/L，青豆、菠菜、生菜与苋菜的最大允许砷浓度为500 μg/L。在砷污染区域，可采取的污染防控措施包括种植番茄、秋葵等果菜类蔬菜，以及采用蒸制而非水煮的烹饪方式。