*1.1. Nanomaterials*

Nanomaterials are incredibly small particles, as tiny as 10,000 times smaller than a human hair. To be considered as "nano", they must have at least one dimension that is less than 100 nanometers. They can be found in various everyday products, such as food, cosmetics, textiles, electronics, etc. [1,2].

Nanomaterials have unique characteristics that make them very valuable. This is due not only to their miniature size but also factors such as shape and surface area. In reality, the properties of nanomaterials may differ significantly from those of the same materials at larger scales [1,2].

Due to these distinctions in properties, nanomaterials bring new and exciting possibilities to different industries and areas, such as engineering, information technology, medicine, and pharmaceuticals. However, the same characteristics that give nanomaterials their special properties can also lead to potential impacts on human health and the environment [1–4].

**Citation:** Ramos, D.; Almeida, L. Managing Nanomaterials in the Workplace by Using the Control Banding Approach. *Int. J. Environ. Res. Public Health* **2023**, *20*, 6011. https://doi.org/10.3390/ ijerph20116011

Academic Editors: Paul B. Tchounwou and Jun Hou

Received: 22 February 2023 Revised: 1 May 2023 Accepted: 29 May 2023 Published: 31 May 2023

**Copyright:** © 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

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Nanomaterials can be found naturally, such as in volcano emissions, or as a result of human activities, such as diesel exhaust fumes or tobacco smoke. Of particular interest are manufactured nanomaterials designed specifically for a certain use, which are already being incorporated into a vast array of products and applications.

Some nanomaterials have been used for many years, such as synthetic amorphous silica in concrete and food products, while others are more recent discoveries, such as nano-titanium dioxide, used as a UV blocking agent in paints and sunscreens; nano-silver, used as an anti-microbial in textiles and medical applications; or carbon nanotubes, which are used for their mechanical strength, light weight, heat dissipation properties, and electrical conductivity in fields such as electronics, energy storage, spacecraft and vehicle structures, and sports equipment. The market for nanomaterials is rapidly growing and new generations of nanomaterials are being developed at a fast pace. Note that despite the numerous advantages of nanomaterials, there is still a significant amount of knowledge missing regarding their potential health risks [1,4].

In fact, there are significant concerns regarding the health effects of nanomaterials [4]. The Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR) found that there are proven health hazards associated with a number of manufactured nanomaterials. Not all nanomaterials necessarily have a toxic effect, however, and a case-by-case approach is necessary while ongoing research continues [2].

The most significant effects of nanomaterials have been observed in the lungs, including inflammation, tissue damage, fibrosis, and the generation of tumors. The cardiovascular system may also be affected. Some types of carbon nanotubes have been shown to have effects similar to asbestos. Nanomaterials have been found to reach other organs and tissues, such as the liver, kidneys, heart, brain, skeleton, and soft tissues. The small size and large surface area of particulate nanomaterials in powder form can pose a risk of explosion, while their coarser materials may not [2,5].

Workers can be exposed to nanomaterials in various work environments where nanomaterials are used, handled, or processed, which can cause them to become airborne and potentially inhaled or come into contact with the skin. This type of exposure is most common during the production stage, but workers throughout the supply chain may also come into contact with nanomaterials without realizing it [4]. This raises concerns about the lack of measures in place to prevent exposure, making it crucial to educate workers about the potential risks. The European Agency for Safety and Health at Work (EU-OSHA) has published several resources on risk awareness and communication related to nanomaterials in the workplace [1].
