Khan Anwar Ul Haq, Liu Yanju, Naidu Ravi, Fang Cheng, Shon Ho Kyong, Zhang Huiming, Dharmarajan Rajarathnam
Global Centre for Environmental Remediation (GCER), College of Engineering Science and Environment, The University of Newcastle, Callaghan, NSW 2308, Australia.
crc for Contamination Assessment and Remediation of the Environment (crcCARE), ATC Building, The University of Newcastle, Callaghan, NSW 2308, Australia.
Toxics. 2024 Aug 18;12(8):602. doi: 10.3390/toxics12080602.
The increasing utilization of zinc oxide nanoparticles (ZnO-NPs) in many consumer products is of concern due to their eventual release into the natural environment and induction of potentially adverse impacts. The behaviour and environmental impacts of ZnO-NPs could be altered through their interactions with environmentally coexisting substances. This study investigated the changes in the behaviour of ZnO-NPs in the presence of coexisting organic pollutants (such as perfluorooctanoic acid [PFOA]), natural organic substances (i.e., humic acid [HA]), and electrolytes (i.e., NaCl and CaCl) in simulated waters. The size, shape, purity, crystallinity, and surface charge of the ZnO-NPs in simulated water after different interaction intervals (such as 1 day, 1 week, 2 weeks, and 3 weeks) at a controlled pH of 7 were examined using various characterization techniques. The results indicated alterations in the size (such as 162.4 nm, 1 day interaction to >10 µm, 3 weeks interaction) and zeta potential (such as -47.2 mV, 1 day interaction to -0.2 mV, 3 weeks interaction) of the ZnO-NPs alone and when PFOA, electrolytes, and HA were present in the suspension. Different influences on the size and surface charge of the nanoparticles were observed for fixed concentrations (5 mM) of the different electrolytes. The presence of HA-dispersed ZnO-NPs affected the zeta potential. Such dispersal effects were also observed in the presence of both PFOA and salts due to their large aliphatic carbon content and complex structure. Cation bridging effects, hydrophobic interactions, hydrogen bonding, electrostatic interactions, and van der Waals forces could be potential interaction forces responsible for the adsorption of PFOA. The presence of organic pollutants (PFOA) and natural organic substances (HA) can transform the surface characteristics and fate of ZnO-NPs in natural and sea waters.
由于氧化锌纳米颗粒（ZnO-NPs）最终会释放到自然环境中并引发潜在的不利影响，其在许多消费品中的使用日益增加令人担忧。ZnO-NPs与环境中共存物质的相互作用可能会改变其行为和环境影响。本研究调查了在模拟水中，共存有机污染物（如全氟辛酸[PFOA]）、天然有机物质（即腐殖酸[HA]）和电解质（即NaCl和CaCl）存在时ZnO-NPs行为的变化。使用各种表征技术，在pH值为7的受控条件下，对不同相互作用时间间隔（如1天、1周、2周和3周）后的模拟水中ZnO-NPs的尺寸、形状、纯度、结晶度和表面电荷进行了检测。结果表明，单独的ZnO-NPs以及悬浮液中存在PFOA、电解质和HA时，其尺寸（如162.4 nm，1天相互作用到>10 µm，3周相互作用）和zeta电位（如-47.2 mV，1天相互作用到-0.2 mV，3周相互作用）发生了变化。对于不同电解质的固定浓度（5 mM），观察到对纳米颗粒尺寸和表面电荷的不同影响。HA分散的ZnO-NPs的存在影响了zeta电位。由于其大的脂肪族碳含量和复杂结构，在PFOA和盐同时存在时也观察到了这种分散效应。阳离子桥连效应、疏水相互作用、氢键、静电相互作用和范德华力可能是负责PFOA吸附的潜在相互作用力。有机污染物（PFOA）和天然有机物质（HA）的存在可以改变天然水和海水中ZnO-NPs的表面特性和归宿。
