University of Wisconsin Milwaukee, Department of Geosciences, 3209 North Maryland Avenue, Milwaukee, WI 53211, USA.
University of Wisconsin Milwaukee, Department of Geosciences, 3209 North Maryland Avenue, Milwaukee, WI 53211, USA.
Sci Total Environ. 2020 Nov 15;743:140414. doi: 10.1016/j.scitotenv.2020.140414. Epub 2020 Jun 27.
Childhood Pb exposure is associated with a multitude of poor health outcomes. In food-insecure areas, growing fresh produce in backyard gardens or on vacant industrial properties is seen as an option for parents. The question arises, could Pb accumulate in consumable tissues of common produce when grown in metals-rich soils at concentrations that would pose a risk to children. This study investigated factors contributing to the accumulation of Pb in consumable tissues of nine common produce crops grown in metals-rich soils from backyard gardens and a former industrial property. Pb in consumable tissues was directly quantified at concentrations less than 1 μg g via X-ray fluorescence (XRF) using protocols specifically developed for use in plant matrices. The accumulation of Pb in prepared raw consumable tissues in three Pb-rich soils was the greatest in modified taproot crops (mean Pb of 11.8 ± 14.6 μg g; turnip, beetroot, radish, carrot), with lesser concentrations in fruits (mean Pb of 2.0 ± 3.0 μg g; tomato, pepper), and potatoes (mean Pb of 0.7 ± 1.1 μg g). An exposure risk evaluation using the USFDA IRL for Pb indicates that consumption of less than 1 g of certain produce grown in this study, including produce grown in garden soils from residential properties, drastically increases the risk of Pb exposure in children. This study further indicates that the proportion of Pb contributed to the daily body burden in children from food is far greater than previously understood, and in all modeled cases, the contribution of Pb from food on a daily basis far outweighs the contribution of Pb from drinking water. For an average child, after addressing over-riding soil/dust impacts, addressing food quality is critical to minimizing Pb exposure.
儿童时期的铅暴露与许多健康不良后果有关。在粮食不安全地区，在后院花园或废弃的工业物业上种植新鲜农产品被视为家长的一种选择。问题是，当在富含金属的土壤中种植时，常见农产品的可食用组织中是否会积累铅，其浓度是否会对儿童构成风险。本研究调查了后院花园和前工业物业中富含金属的土壤中种植的 9 种常见农产品可食用组织中铅积累的因素。使用专门为植物基质开发的协议，通过 X 射线荧光（XRF）在浓度低于 1μg/g 时直接定量可食用组织中的 Pb。在三种富含 Pb 的土壤中，准备好的 raw 可食用组织中的 Pb 积累量在改良的直根作物（Pb 平均值为 11.8±14.6μg/g；芜菁、甜菜根、萝卜、胡萝卜）中最高，在水果（Pb 平均值为 2.0±3.0μg/g；番茄、胡椒）和土豆（Pb 平均值为 0.7±1.1μg/g）中的浓度较低。使用美国食品和药物管理局（FDA）的 Pb 暴露风险评估指标（IRL）进行评估表明，食用本研究中种植的某些农产品（包括从住宅物业花园土壤中种植的农产品）的量少于 1g，会大大增加儿童铅暴露的风险。本研究进一步表明，从食物中摄入的 Pb 对儿童体内的每日负担的比例远远高于先前的理解，在所有模型案例中，从食物中摄入的 Pb 量每天都远远超过从饮用水中摄入的 Pb 量。对于一个普通儿童，在解决土壤/灰尘的影响之后，解决食品质量问题对于最大限度地减少 Pb 暴露至关重要。
