Environmental impact of nanomaterials and green nanotechnology

Nanomaterials are used across medicine, electronics, coatings and energy. Their small size and high surface area give them properties that bulk materials do not have, which makes them useful in many applications. But the same properties that make nanomaterials interesting also raise questions about their behaviour in the environment and their effects on human health. This article explains what is known about the environmental impact of nanomaterials, how safe handling is approached and where nanotechnology is contributing to more sustainable processes.

What are engineered nanomaterials?

Engineered nanomaterials are materials deliberately manufactured at the nanoscale, typically between 1 and 100 nanometres. They differ from naturally occurring nanoscale particles, such as sea spray or volcanic ash, because their size, shape and surface chemistry are controlled during production.

The physical and chemical properties of engineered nanomaterials differ from their bulk equivalents. A higher surface area relative to volume makes them more reactive. Size-dependent optical and electronic properties make them useful in solar cells, fuel cells and displays. These same properties also affect how they interact with biological systems and the environment.

Environmental impact of nanomaterials

The environmental impact of nanomaterials depends on the material, its size, shape, surface chemistry and how it enters the environment. Most concern focuses on engineered nanoparticles that are released during manufacturing processes, use or disposal.

Human health

Nanoparticles can enter the body through inhalation, ingestion or skin contact. Inhaled nanoparticles are of particular concern because their small size allows them to penetrate deep into the lungs. Some studies suggest that certain nanoparticles, particularly carbon nanotubes and metal oxide nanoparticles, can cause inflammatory responses in lung tissue. The health effects depend strongly on the specific material and exposure level.

Engineered nanomaterials used in consumer products, such as silver nanoparticles in textiles or titanium dioxide in sunscreen, are subject to ongoing safety assessments. Regulatory frameworks for nanomaterials are still developing. In Europe, the European Commission has introduced reporting obligations for nanomaterials under REACH. In the United States, the Toxic Substances Control Act (TSCA) covers nanoscale materials under its existing chemical substances framework, though specific nano-specific regulations are still being developed.

Environmental remediation and ecotoxicity

Nanoparticles released into water, soil or air can affect ecosystems. Some metal nanoparticles, particularly silver and copper, are toxic to aquatic organisms at low concentrations. The high surface area of nanoparticles makes them reactive, which can accelerate the release of ions in aquatic environments.

At the same time, nanomaterials are used in environmental remediation. Iron nanoparticles are used in water treatment to break down organic pollutants. Titanium dioxide nanoparticles catalyse the breakdown of contaminants in water and air under UV light. The same properties that raise environmental concerns in some contexts enable environmental cleanup in others.

Safe handling of nanomaterials

Working with nanomaterials requires appropriate controls to limit exposure. Because inhalation is the main exposure route, engineering controls that prevent nanoparticles from becoming airborne are the first line of protection. This includes enclosed systems, local exhaust ventilation and HEPA filtered extraction.

Personal protective equipment, including respirators rated for fine particles, gloves and eye protection, is used where engineering controls alone are not sufficient. Standard dust masks do not filter nanoparticles effectively.

Risk assessment for nanomaterials considers the physical and chemical properties of the specific material, the form in which it is used (dry powder versus liquid suspension), the duration and frequency of exposure and the toxicity data available for that material. Many nanomaterials used in liquid formulations, such as nanoparticle inks or colloidal dispersions, pose lower inhalation risks than dry powders because the particles are suspended in liquid rather than airborne.

Green nanotechnology and sustainable applications

Green nanotechnology refers to two related ideas: using nanotechnology to develop more sustainable processes and products, and developing nanotechnology itself in a more sustainable way. Research published in Discover Sustainability outlines how green nanotechnology can contribute to sustainable development goals across energy, water treatment and materials science.

Nanotechnology for sustainability

Nanomaterials are used in several applications that support sustainability goals. In renewable energy, nanoparticles improve the efficiency of solar cells and fuel cells. Nanostructured catalysts reduce the energy needed for chemical reactions in industrial manufacturing processes. Nanoparticle-based water treatment removes contaminants more efficiently than conventional methods.

In coatings, nanomaterial-based functional layers can replace energy-intensive processes. The LaB₆ ink platform from Partners in Chemicals is an example: instead of depositing hard, infrared-absorbing coatings through CVD or PVD at 800–1800°C, the ink dries below 90°C. This reduces energy consumption during coating production significantly. For more on how this works, visit the metal borides page on Partners in Green Chemicals.

Sustainable nanotechnology production

Green synthesis methods use plant extracts or microorganisms to produce metal nanoparticles without harsh chemical reagents. These biological methods reduce waste and avoid the use of toxic solvents compared to conventional chemical synthesis.

Life cycle thinking in nanotechnology considers the full environmental impact of a nanomaterial from production through use to end of life. This includes the energy used in synthesis, the chemicals involved, the durability of the product and how the material behaves when it is eventually released into the environment.

Partners in Green Chemicals and sustainable coating technology

Partners in Green Chemicals develops and supplies functional nanomaterials with a focus on more sustainable processing. The LaB₆ ink platform is a concrete example: hard, infrared-absorbing coatings that are applied at temperatures below 90°C rather than the 800 – 1800°C needed for CVD or PVD. This reduces energy consumption during production and makes it possible to coat flexible and heat-sensitive substrates that conventional methods cannot reach.

The most promising nanotechnology applications for sustainability

Several nanotechnology applications are currently attracting attention for their potential contribution to sustainability and human health.

Energy

Nanostructured materials in solar cells increase light absorption and energy conversion. Nanoparticle catalysts in fuel cells improve efficiency and reduce the need for expensive platinum. These applications support the shift toward renewable energy.

Medicine

Targeted drug delivery using nanoparticles reduces the side effects of cancer treatment by concentrating drugs at the tumour site. Nanoparticle-based diagnostics improve the sensitivity of medical imaging. These applications could reduce the overall burden of treatment and improve patient outcomes.

Water and environment

Nanomaterial-based filters and catalysts address water scarcity and contamination, which are among the most pressing environmental challenges. Iron nanoparticles remove heavy metals and organic contaminants from groundwater. Photocatalytic nanoparticles break down pollutants in water and air.

Coatings and materials

Functional nanoparticle coatings reduce energy consumption in buildings and vehicles by blocking solar heat gain. Hard nanoparticle coatings extend the service life of materials, reducing the frequency of replacement and the resources needed for maintenance.

Frequently asked questions

Summary

Engineered nanomaterials offer significant benefits across energy, medicine, coatings and environmental remediation. Their environmental impact depends on the specific material, form and exposure route. Safe handling in occupational settings relies on engineering controls, HEPA filtered extraction and personal protective equipment. Green nanotechnology reduces the environmental footprint of both nanomaterial production and the products that use them. Low-temperature coating processes using nanoparticle inks, such as the LaB₆ ink platform, use significantly less energy than conventional CVD or PVD methods and can be applied to substrates that those methods cannot reach.