A recent paper entitled “Assessing the Release of Microplastics and Nanoplastics from Plastic Containers and Reusable Food Pouches: Implications for Human Health” (1) was published in this journal. The authors assessed the release of microplastics and nanoplastics (MNPs) under various consumer usage conditions of baby food containers or pouches, such as refrigeration, room-temperature storage, or microwave heating (MH). They found that compared to other usage scenarios, MH caused the highest release of MNPs. We do not dispute the highest release of MH in the authors’ group setting. However, MH is characterized by a rapid heating rate, achieving higher temperatures within the same time compared to conventional heating methods. Additionally, a high temperature is an important risk factor for microplastic release. (2,3) It is necessary for us to point out, therefore, that the release of MNPs in the MH group might be caused by the high-temperature heating of the plastic containers. MH, a fast and convenient heating method, is widely used in everyday heating scenarios. We are worried that their statements might misdirect consumers about the unsafe use of microwaves in food heating. Our team has been dedicated to exploring the application of microwave technology in food processing for more than 15 years. MH exhibits distinct differences in energy input and heating rate compared with traditional heating methods. To mitigate the effects of microwave’s rapid heating, we commonly compare MH with other traditional heating methods, for example, water bath heating (WH), at equivalent heating rates. Likewise, we propose that the impact of MH on the release of MNPs should be compared to that of a water bath at equivalent heating rates. Hence, we accessed the release of MNPs from microwave-safe baby food containers heated by microwave and water bath at the same heating rates. Three containers, labeled polypropylene (PP), were purchased from Amazon and Taobao. Our results showed that different heating methods showed comparable orders of magnitude in their impact on MNPs (Figure 1a). The release of nanoplastics reached ∼10⁷ particles/cm², while the release of microplastics was ∼10⁶ particles/cm². More microplastics were released at higher temperatures, and the microplastic release at 40 °C was 1 order of magnitude lower than that at higher temperatures (Figure 1b). Furthermore, we assessed the release from the three brands of baby food containers heated to 95 °C at an enhanced heating rate. MNPs released from three brands under two heating methods remained within the same order of magnitude. Surprisingly, increasing the rate of heating produced fewer microplastics [decreased by 3 orders of magnitude (Figure 1c,d)] (relative percentage of particle size shown in Figures S2 and S4). Additionally, we employed Py-GCMS to detect the total amount of PP released from brand 1 heated to 95 °C. The amounts of PP in the MH and WH groups were 0.025 and 0.009 μg/cm², respectively (Figure S5). These figures, although relatively small compared to those of the other samples, (4,5) still pose unknown risks. Figure 1. Release of nanoplastics and microplastics. (a and b) Counts of nanoplastics and microplastics at the same heating rates at different temperatures. (c and d) Counts of nanoplastics and microplastics of different brands released at increased heating rates at 95 °C. Our findings preliminarily confirm that different heating methods showed comparable orders of magnitude in their impact on MNPs; in other words, MH does not excessively increase the release of MNPs over WH at equivalent heating rates. Moreover, a high heating rate might reduce the release of microplastics. Thus, the highest release of MNPs in their experiments is likely due to the high temperature achieved during MH. We reiterate that our comment does not negate the results of Hussain et al. Instead, we aim to alleviate unnecessary panic regarding the use of microwaves for heating. Because heating is inevitable in daily scenarios and microwaves serve as an efficient way of daily heating, controlling the appropriate power and heating time and selecting suitable containers make it a safe and effective heating method for consumers. In our opinion, more emphasis should be placed on parameter control and appropriate container selection for MH. The Supporting Information is available free of charge at https://pubs.acs.org/doi/10.1021/acs.est.4c02467. Further experimental details, heating curves, and relative percentage of particle size (PDF) Most electronic Supporting Information files are available without a subscription to ACS Web Editions. Such files may be downloaded by article for research use (if there is a public use license linked to the relevant article, that license may permit other uses). Permission may be obtained from ACS for other uses through requests via the RightsLink permission system: http://pubs.acs.org/page/copyright/permissions.html. This research was supported by the National Natural Science Foundation of China (32225040 and 32272472). The authors would like to thank professor Zhenyu Wang and associate professor Xiaona Li from the School of Enviornment and Ecology of Jiangnan University for their methodological guidance. This article references 5 other publications. This article is cited by 1 publications. Figure 1. Release of nanoplastics and microplastics. (a and b) Counts of nanoplastics and microplastics at the same heating rates at different temperatures. (c and d) Counts of nanoplastics and microplastics of different brands released at increased heating rates at 95 °C. This article references 5 other publications. The Supporting Information is available free of charge at https://pubs.acs.org/doi/10.1021/acs.est.4c02467. Further experimental details, heating curves, and relative percentage of particle size (PDF) Most electronic Supporting Information files are available without a subscription to ACS Web Editions. Such files may be downloaded by article for research use (if there is a public use license linked to the relevant article, that license may permit other uses). Permission may be obtained from ACS for other uses through requests via the RightsLink permission system: http://pubs.acs.org/page/copyright/permissions.html.

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关于“评估塑料容器和可重复使用食品袋中微塑料和纳米塑料的释放：对人类健康的影响”的通讯


该期刊最近发表了一篇题为“评估塑料容器和可重复使用食品袋中微塑料和纳米塑料的释放：对人类健康的影响”(1) 的论文。作者评估了婴儿食品容器或袋在不同消费者使用条件下的微塑料和纳米塑料 (MNP) 释放量，例如冷藏、室温储存或微波加热 (MH)。他们发现，与其他使用场景相比，MH 导致 MNP 的释放量最高。我们对作者群体中 MH 的最高版本没有异议。然而，与传统的加热方法相比，MH的特点是加热速度快，在相同的时间内可以达到更高的温度。此外，高温是微塑料释放的一个重要风险因素。 (2,3)因此，我们有必要指出，MH组中MNPs的释放可能是由塑料容器的高温加热引起的。 MH是一种快速、便捷的加热方式，广泛应用于日常取暖场景。我们担心他们的言论可能会误导消费者，让他们认识到微波加热食物不安全。我们的团队15年来一直致力于探索微波技术在食品加工中的应用。与传统加热方法相比，MH在能量输入和加热速率方面表现出明显的差异。为了减轻微波快速加热的影响，我们通常在相同的加热速率下将 MH 与其他传统加热方法（例如水浴加热 (WH)）进行比较。同样，我们建议将 MH 对 MNP 释放的影响与同等加热速率下的水浴进行比较。 因此，我们通过微波和水浴以相同的加热速率加热的微波炉安全婴儿食品容器中释放了 MNP。三个容器，贴有聚丙烯 (PP) 标签，购自亚马逊和淘宝。我们的结果表明，不同的加热方法对 MNP 的影响具有相当的数量级（图 1a）。纳米塑料的释放量达到~10 ⁷ 颗粒/cm ² ，而微塑料的释放量为~10 ⁶ 颗粒/cm ² 。温度越高，释放的微塑料越多，40℃时的微塑料释放量比较高温度时低1个数量级（图1b）。此外，我们还评估了以更高的加热速率加热至 95 °C 的三个品牌婴儿食品容器的释放情况。三个品牌在两种加热方法下释放的 MNP 保持在同一数量级。令人惊讶的是，增加加热速率产生了更少的微塑料[减少了3个数量级（图1c、d）]（颗粒尺寸的相对百分比如图S2和S4所示）。此外，我们使用 Py-GCMS 检测品牌 1 加热至 95 °C 时释放的 PP 总量。 MH组和WH组的PP含量分别为0.025和0.009μg/cm ² （图S5）。这些数字虽然与其他样本相比相对较小，但 (4,5) 仍然构成未知的风险。图 1. 纳米塑料和微塑料的释放。 (a和b)在不同温度下相同加热速率下纳米塑料和微塑料的计数。 (c 和 d) 在 95 °C 下增加加热速率时释放的不同品牌的纳米塑料和微塑料的计数。 我们的研究结果初步证实，不同的加热方法对 MNP 的影响具有可比的数量级；换句话说，在相同的加热速率下，与 WH 相比，MH 不会过度增加 MNP 的释放。此外，高加热速率可能会减少微塑料的释放。因此，他们的实验中 MNP 的最高释放可能是由于 MH 期间达到的高温所致。我们重申，我们的评论并不否定侯赛因等人的结果。相反，我们的目标是减轻有关使用微波炉加热的不必要的恐慌。由于加热是日常生活中不可避免的事情，而微波作为日常加热的有效方式，控制合适的功率和加热时间以及选择合适的容器对于消费者来说是一种安全有效的加热方式。我们认为，MH 应该更加重视参数控制和合适的容器选择。支持信息可在 https://pubs.acs.org/doi/10.1021/acs.est.4c02467 免费获取。更多实验细节、加热曲线和相对粒径百分比 (PDF) 大多数电子支持信息文件无需订阅 ACS 网络版即可获得。此类文件可以按文章下载用于研究用途（如果有链接到相关文章的公共使用许可证，则该许可证可能允许其他用途）。可以通过 RightsLink 许可系统提出请求，从 ACS 获得许可用于其他用途：http://pubs.acs.org/page/copyright/permissions.html。该研究得到了国家自然科学基金项目（32225040和32272472）的支持。 作者感谢江南大学环境与生态学院王振宇教授和李晓娜副教授的方法指导。本文参考了其他 5 篇出版物。这篇文章被 1 篇出版物引用。图 1. 纳米塑料和微塑料的释放。 （a和b）在不同温度下相同加热速率下纳米塑料和微塑料的计数。 (c 和 d) 在 95 °C 下增加加热速率时释放的不同品牌的纳米塑料和微塑料的计数。本文参考了其他 5 篇出版物。支持信息可在 https://pubs.acs.org/doi/10.1021/acs.est.4c02467 免费获取。更多实验细节、加热曲线和相对粒径百分比 (PDF) 大多数电子支持信息文件无需订阅 ACS 网络版即可获得。此类文件可以按文章下载用于研究用途（如果有链接到相关文章的公共使用许可证，则该许可证可能允许其他用途）。可以通过 RightsLink 许可系统提出请求，从 ACS 获得许可用于其他用途：http://pubs.acs.org/page/copyright/permissions.html。