Are nanoplastics dangerous for humans and the environment?
Due to their small size (1 nm – 1 µm), nanoplastic particles can overcome certain barriers and accumulate in organisms or environmental compartments. In addition, undesirable chemicals such as flame retardants or plasticizers can bind to the nanoplastic particles and be released later, e.g. after uptake in environmental organisms. Currently, the estimated concentration of nanoplastics in the environment is very low and has no serious impact on plants and animals.
Microplastic (1 µm – 1 mm) particles currently pose a greater threat to humans and the environment due to higher measured environmental concentrations. Research groups around the world are currently working on this topic. It is expected that the number of microplastics as well as nanoplastic particles will strongly increase worldwide in the next decades via the gradual decomposition of plastics in the environment.
- For more information on this topic, please refer to the article in our cross cutting section “Nanoplastic in the environment”
How efficient are nanomaterials removed from wastewater in the wastewater treatment plant?
In the wastewater treatment plant, contaminants including nanomaterials are separated from the wastewater in several stages. According to laboratory tests, the most common nanomaterials such as silicon dioxide, titanium dioxide, silver or zinc compounds are effectively removed from the wastewater by 90-95%. Only a small fraction of nanomaterials remains in the treated water. The majority of the removed nanomaterials are found in the sewage sludge, which is further treated separately.
- For more information on this topic, please refer to the article in our cross cutting section “Nanomaterials in the wastewater treatment plant”.
Are nanomaterials a threat for our wastewater treatment plants?
No, studies to date cannot prove that nanomaterials pose a risk to our wastewater treatment plants. But a possible cause of concern is the targeted use of nanomaterials with antibacterial properties. They could kill the bacteria in the biological treatment stages. However, the amounts of nanomaterials in the wastewater and later in the sewage treatment plant are too small to disrupt the work of the bacteria in the biological purification stage.
- For more information on this topic, please refer to the article in our cross cutting section “Nanomaterials in the wastewater treatment plant”
Why are currently nanomaterial quantities in the environment mostly calculated theoretically?
Currently, it is very difficult and tedious to directly detect engineered nanomaterials in the environment. There are still large knowledge gaps about the exposure, interactions and residence time of nanomaterials in the environment. Computer models can help to simulate such complex situation. However, this requires making certain assumptions and simplifications so that the theoretical values do not reflect the real quantities of nanomaterials in the environment. Such model calculations are a good tool for estimating risks and interactions of nanomaterials in the environment.
For more information on this topic, please refer to the article in our cross cutting section “Estimating the occurrence of nanomaterials in the environment”
Do nanomaterials harm pollinating insects?
Pollinating insects may encounter nanomaterials via the pollen, which is contaminated via application of nanomaterial-containing pesticides or fertilizers brought out on crops, and from traffic exhaust. While laboratory studies showed that nanomaterial can be harmful to some insects, it is unclear whether the low concentrations of nanomaterials found in outdoor environments do harm pollinators.
Read more about this topic in our cross cutting articles