Final Report Summary - NANOSH (Inflammatory and genotoxic effects of engineered nanomaterials)
Nanotechnology, - a production based on different nano-sized particles - is a rapidly increasing area of industry providing new and innovative solutions that are being introduced into many industrial sectors. In the near future, it will have a major impact on the everyday life of people in industrialised countries and, therefore, there are increasing demands by society for reliable and understandable information on the possible health effects of engineered nanoparticles. It is essential that reliable information is gathered before the widespread use of nanoparticles, to avoid potential health problems. The present research project focused on occupational exposure to nanoparticles and their health effects.
One goal of the research was to characterise the levels of exposure to specific engineered nanoparticles. Exposure levels were evaluated both under laboratory conditions and during the manufacture of the particles. The particles were characterised with respect to their morphology and particle-size distribution, surface activity, and potential for agglomerate formation.
The overall goal of the project was to delineate the health effects of selected nano-sized particles relevant to the occupational environment. The health effects studied included genotoxicity, pulmonary inflammatory responses, and effects on the vasculature.
The information gathered together with the state-of-the-art technology utilised in these studies increase our knowledge on nanoparticles and help to create a reliable basis for the evaluation of possible health risks associated with these new materials.
This project brought together expertise from different research areas highly relevant for assessing the safety of nanoparticles and will thereby significantly promote the formation of new centres of excellence and a competitive European Research Area (ERA) in this rapidly evolving area.
The findings of the project have a significant socio-economic impact on European capability of conducting research and innovation in the area of nanotechnology. Assuring the safety of new nanomaterials is a crucial prerequisite for successful promotion of nanotechnological innovations and their applications in the future. This research creates a reliable and sound foundation for the assessment of safety of the chosen nano-sized particles and products containing nanoparticles and in this way encourages nanotechnological advances to support European national economies and the prosperity and wellbeing of citizens in the EU Member States.
The project provides essential information which can be used on a wider basis for assessing occupational and other safety risks associated with the production and use of nanoparticles. Essential products that serve these scientific and technological goals are means and methods to characterise particle properties, ways to carry out reliable exposure assessments, and models for assessing key-health effects - all important components of the safety evaluation of engineered nanoparticles.
The consortium developed models for a thorough characterisation of nanoparticles and their dispersions, which were used in the toxicity tests performed during the project. The models have been published and can be utilised by others, as well. A number of nanomaterials were selected for the NANO ATLAS database (available both in printed and electronic form), providing examples of the most relevant nanomaterials used in commercial applications such as carbon nanotubes, fullerenes, metal particles, metal oxide particles, quantum dots and some experimental nanoparticles.
Furthermore a strategy for assessing exposure to ENPs in a range of workplaces was developed. Solutions for background discrimination were explored. A decision logic for determining whether workers were likely to be exposed to ENPs was developed. Measurements were carried out in many types of workplaces from university research laboratories to large-scale production plants, where a wide range of ENPs are produced or handled. The nucleus for a database was developed where results of workplace measurements are stored with the aim to be accessible for anyone to use and add data to.
Methods were developed for genotoxicity assessment of nanomaterials in vitro and in vivo. Most nanoparticles were able to damage DNA in vitro, and for TiO2 this seemed to be due to primary oxidative DNA damage. No induction of malondialdehyde DNA adducts was seen, suggesting that secondary genotoxic effects due to lipid peroxidation were not involved. Mesothelial cells were more sensitive than bronchial epithelial cells to the DNA-damaging effect of nanoparticles. Some nanomaterials were also capable of increasing chromosome damage in vitro, zinc oxide showing the clearest effect. In human lymphocytes, structural chromosomal aberrations were only obtained by a prolonged in vitro treatment. Inhalation of TiO2 did not affect the level of DNA or chromosome damage in mice. These findings were presented in a number of scientific publications.
Also assessed was the toxicity and immune activation ability of five nanomaterials on antigen presenting cells that are the first responders of the immune defence and showed an induction of macrophage activation after exposure to all the materials studied. In vivo tests showed that healthy mice elicited pulmonary neutrophilia accompanied by chemokine CXCL5 expression when exposed to nanosized TiO2. Asthmatic mice showed remarkable suppression of most mediators and signs of allergic asthma when exposed to either nanosized or coarse TiO2. We could see that levels of leucocytes, cytokines, chemokines and antibodies relevant in allergic asthma as well as airway hyperresponsiveness were all decreased or even returned to a level normal in healthy mice. Our results suggest that repeated airway exposure to TiO2 particles modulates the airway inflammation depending on the allergic status of the exposed mice. Interestingly, the level of lung inflammation could not be explained by the surface area of the particles, their primary or agglomerate particle size, or radical formation capacity, but was rather associated with the surface coating. Our findings emphasise that it is vitally important for risk assessment to take into account that modifications, e.g. by surface coating, may drastically change the toxicological potential of nanoparticles. The findings were published in the scientific literature.
These in vitro and in vivo findings strongly corroborate the view that, in addition to size and shape, the surface chemistry of nanomaterials strongly affects their fate as well as their biological effects in vitro and in vivo and thus is a crucial parameter to be considered with regard to their toxicity but also concerning potential biomedical applications. The results obtained were reported in several original articles.
One goal of the research was to characterise the levels of exposure to specific engineered nanoparticles. Exposure levels were evaluated both under laboratory conditions and during the manufacture of the particles. The particles were characterised with respect to their morphology and particle-size distribution, surface activity, and potential for agglomerate formation.
The overall goal of the project was to delineate the health effects of selected nano-sized particles relevant to the occupational environment. The health effects studied included genotoxicity, pulmonary inflammatory responses, and effects on the vasculature.
The information gathered together with the state-of-the-art technology utilised in these studies increase our knowledge on nanoparticles and help to create a reliable basis for the evaluation of possible health risks associated with these new materials.
This project brought together expertise from different research areas highly relevant for assessing the safety of nanoparticles and will thereby significantly promote the formation of new centres of excellence and a competitive European Research Area (ERA) in this rapidly evolving area.
The findings of the project have a significant socio-economic impact on European capability of conducting research and innovation in the area of nanotechnology. Assuring the safety of new nanomaterials is a crucial prerequisite for successful promotion of nanotechnological innovations and their applications in the future. This research creates a reliable and sound foundation for the assessment of safety of the chosen nano-sized particles and products containing nanoparticles and in this way encourages nanotechnological advances to support European national economies and the prosperity and wellbeing of citizens in the EU Member States.
The project provides essential information which can be used on a wider basis for assessing occupational and other safety risks associated with the production and use of nanoparticles. Essential products that serve these scientific and technological goals are means and methods to characterise particle properties, ways to carry out reliable exposure assessments, and models for assessing key-health effects - all important components of the safety evaluation of engineered nanoparticles.
The consortium developed models for a thorough characterisation of nanoparticles and their dispersions, which were used in the toxicity tests performed during the project. The models have been published and can be utilised by others, as well. A number of nanomaterials were selected for the NANO ATLAS database (available both in printed and electronic form), providing examples of the most relevant nanomaterials used in commercial applications such as carbon nanotubes, fullerenes, metal particles, metal oxide particles, quantum dots and some experimental nanoparticles.
Furthermore a strategy for assessing exposure to ENPs in a range of workplaces was developed. Solutions for background discrimination were explored. A decision logic for determining whether workers were likely to be exposed to ENPs was developed. Measurements were carried out in many types of workplaces from university research laboratories to large-scale production plants, where a wide range of ENPs are produced or handled. The nucleus for a database was developed where results of workplace measurements are stored with the aim to be accessible for anyone to use and add data to.
Methods were developed for genotoxicity assessment of nanomaterials in vitro and in vivo. Most nanoparticles were able to damage DNA in vitro, and for TiO2 this seemed to be due to primary oxidative DNA damage. No induction of malondialdehyde DNA adducts was seen, suggesting that secondary genotoxic effects due to lipid peroxidation were not involved. Mesothelial cells were more sensitive than bronchial epithelial cells to the DNA-damaging effect of nanoparticles. Some nanomaterials were also capable of increasing chromosome damage in vitro, zinc oxide showing the clearest effect. In human lymphocytes, structural chromosomal aberrations were only obtained by a prolonged in vitro treatment. Inhalation of TiO2 did not affect the level of DNA or chromosome damage in mice. These findings were presented in a number of scientific publications.
Also assessed was the toxicity and immune activation ability of five nanomaterials on antigen presenting cells that are the first responders of the immune defence and showed an induction of macrophage activation after exposure to all the materials studied. In vivo tests showed that healthy mice elicited pulmonary neutrophilia accompanied by chemokine CXCL5 expression when exposed to nanosized TiO2. Asthmatic mice showed remarkable suppression of most mediators and signs of allergic asthma when exposed to either nanosized or coarse TiO2. We could see that levels of leucocytes, cytokines, chemokines and antibodies relevant in allergic asthma as well as airway hyperresponsiveness were all decreased or even returned to a level normal in healthy mice. Our results suggest that repeated airway exposure to TiO2 particles modulates the airway inflammation depending on the allergic status of the exposed mice. Interestingly, the level of lung inflammation could not be explained by the surface area of the particles, their primary or agglomerate particle size, or radical formation capacity, but was rather associated with the surface coating. Our findings emphasise that it is vitally important for risk assessment to take into account that modifications, e.g. by surface coating, may drastically change the toxicological potential of nanoparticles. The findings were published in the scientific literature.
These in vitro and in vivo findings strongly corroborate the view that, in addition to size and shape, the surface chemistry of nanomaterials strongly affects their fate as well as their biological effects in vitro and in vivo and thus is a crucial parameter to be considered with regard to their toxicity but also concerning potential biomedical applications. The results obtained were reported in several original articles.
