Wang Meichen, Hearon Sara E, Johnson Natalie M, Phillips Timothy D
Veterinary Integrative Biosciences Department, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843, USA.
Environmental and Occupational Health, School of Public Health, Texas A&M University, College Station, TX 77843, USA.
Appl Clay Sci. 2019 Feb;168:196-202. doi: 10.1016/j.clay.2018.11.010. Epub 2018 Nov 20.
People and animals can be unintentionally exposed to complex mixtures of hazardous chemicals that can threaten the safety of food and water supplies following natural and man-made disasters and emergencies. Our research has focused on the development of broad-acting adsorbents that will tightly bind environmental contaminants in the gastrointestinal tract and decrease their bioavailability to humans and animals during these events. In this study, benzo[a]pyrene (BaP) and aldicarb were used as representative chemicals due to their high toxicity and extensive distribution in the environment. Both chemicals have been commonly detected in water and sediments in the US, and their distribution and concentrations can be enhanced during disasters. To address this problem, we have amended and functionalized montmorillonite clays with the nutrients, L-carnitine and choline to enhance their attraction for lipophilic toxins, such as BaP and aldicarb. Based on equilibrium isothermal analyses, we have demonstrated a significantly increased binding capacity (Qmax) and affinity (Kd) for BaP and aldicarb compared to the parent clay. Adsorption isotherms also showed that talc bound strongly to BaP with the highest Qmax, which was twice that of activated carbon. Additionally, cultures of adult hydra with a metabolism activation package were used as an toxicity indicator to confirm the ability of test adsorbents to protect against toxicity at low inclusion levels. We anticipate that the optimal adsorbents developed can be delivered in food and flavored water, or administered by sachet or capsule during emergencies and disasters to decrease human and animals exposures to environmental toxins.
在自然和人为灾害及紧急情况发生后，人和动物可能会意外接触到复杂的有害化学物质混合物，这些混合物会威胁到食物和水供应的安全。我们的研究重点是开发具有广泛作用的吸附剂，这种吸附剂能在胃肠道中紧密结合环境污染物，并在这些情况下降低它们对人和动物的生物利用度。在本研究中，苯并[a]芘（BaP）和涕灭威因其高毒性和在环境中的广泛分布而被用作代表性化学物质。这两种化学物质在美国的水和沉积物中都经常被检测到，并且在灾害期间它们的分布和浓度会增加。为了解决这个问题，我们用营养物质L - 肉碱和胆碱对蒙脱石粘土进行了改性和功能化处理，以增强它们对亲脂性毒素（如BaP和涕灭威）的吸附能力。基于平衡等温线分析，我们证明与原始粘土相比，对BaP和涕灭威的结合能力（Qmax）和亲和力（Kd）显著提高。吸附等温线还表明，滑石粉与BaP的结合力很强，Qmax最高，是活性炭的两倍。此外，使用具有代谢激活包的成年水螅培养物作为毒性指标，以确认测试吸附剂在低添加水平下防止毒性的能力。我们预计，开发出的最佳吸附剂可以添加到食物和调味水中，或者在紧急情况和灾害期间通过小袋或胶囊给药，以减少人和动物对环境毒素的接触。
