Multimodal characterisation of nanomaterials in the environment

Lead Research Organisation: University of Bristol
Department Name: Interface Analysis Centre

Abstract

Engineered nanomaterials (ENMs) are found in many consumer products including cosmetics and personal hygiene goods. Nanomaterials are also found in additives for diesel fuels to improve fuel efficiency. These materials will come into contact with the environment, for example, if they are washed down the sink, or if they become airbourne, however we currently have no idea about whether they are hazardous or not and regulations are not in place to control their release or treatment. The life cycle of ENMs in the environment is not known and there exist large knowledge gaps in this field. The reason for this is that the concentrations and properties of ENMs in consumer products are largely unknown (or not indicated bycompanies). Very little is known about the behaviour or lifetime of ENMs in the water effluent and soils as it's extremely hard to monitor this behaviour, as we do not have the tools to detect these tiny materials in very complex environments. This project will apply new and sophisticated experimental characterization tools for predicting potential environmental risks associated with the use of selected consumer products incorporating ZnO, Ag, TiO2 and CeO2 ENMs. An overarching goal is to evaluate which are the critical charateristics of ENMs (size, chemistry etc.) which may cause damage to the environment through two of the most predominant environmental pathways - from the effluent of a waste water treatment plant to waters and also from sewage sludge to soils. This information will ultimately to provide guidance to regulators on policy and to industry about how to design "safe" classes of ENMs and mitigate against risk, while avoiding overregulation. Avoiding overregulation is vital, as we do not want to re-experience what happened e.g. at Fukushima, where 160,000 people were forced to relocated without need, since the risk presented to regulators and the government was too high. This has since resulted in 1,599 deaths, as the displaced residents are suffering from health problems, alcoholism and high rates of suicide.

Our team has an extensive track record in developing unique techniques to track these nanomaterials in complex environments and will apply their knowledge of this field to tackle this extremely pertinent concern. The projects experimental approaches include both physical science experiments and toxicological approaches, generating results to improve our limited understanding of the potential environmental hazards. The results generated from the project will also contribute to our very limited knowledge on various aspects of the fate, transport, bioavailability, and ecotoxicity of ENMs and will allow us to answer questions such as "can toxic doses of ENMs reach organisms or are these concentrations negligible at the point of exposure to the organism?", "if they are toxic, is it possible to re-engineer ENMs such that they do not present a risk", "do the nanomaterials dissolve or change their chemistry in the environment and ultimately detoxify and how does this vary between the different nanomaterials?", "which nanomaterials present the greatest risk and how do we minimise the environmental and health risks of these hazardous materials without overly precautionary regulations". This multifaceted strategy will make a major development in understanding the fate of ENMs in the environment to guide policy regulation whilst avoiding unnecessary overregulation, and ultimately guide the safe development of these materials for future commercial exploitation.

Planned Impact

With increasing commercialisation and up-scaling of silver, zinc oxide, ceria and titania nanomaterials production, comes a concomitant need to understand occupational health, public safety and environmental implications of these materials. Due to the enormous number of permutations of nanoparticles shape, dimensions, composition, and surface chemistry, only a fundamental understanding of the critical processes will allow a realistic, practical assessment of the risks of wide range of possible products. The proposed work will impact on ENM development by establishing the relative environmental risk associated with different classes of ENMs. By establishing the potential of each classes of ENM for any environmental risks, suitable precautionary measures can be identified. At the moment, the uncertainty surrounding ENM safety is a major barrier to commercial development. By establishing a higher level of confidence about safe handling of these classes of ENM, this project will have a major economic impact. Nanoscale studies of the complex environment-nano interface lie at the heart of technical challenges. Despite numerous reports, there is no consensus regarding environmental toxicity enacted by these nanomaterials due to a lack of understanding of their lifecycle in the environment. This project will make a step-change in our understanding of the fate of these nanomaterials and their ultimate bioreactivity with organisms. The following groups will benefit:

a. ENM manufacturers and their customers: Businesses will be able to make informed decisions about which technologies to pursue. Alternatively, they will be able to select effective safety measures or potentially redesign their products to avoid any potential hazards.

b. Government, society and policy makers: The Environment Agency and the Department for the Environment, Food and Rural Affairs will benefit from insight to any hazards associated with these classes of ENMs to recommend on policy and regulations to ensure safe handling in the workplace and the environment. The health and safety executive has been working hard recently to provide appropriate and balanced advice to companies working in the area; the outputs of this project will help them to refine their advice. The Royal Commission on Environmental Pollution and Royal Society are actively involved with public engagement in the field of environmental and nanotoxicology and will also benefit from this research which will feed into reports, commissions and recommendations made by these and similar societies.

c. Society: Clearly, workers in the ENM and water industries need to be protected adequately from any potential risks whilst maximizing their productivity; only with a detailed understanding of ENM toxicology, can appropriate control measures be selected. More generally, the public will benefit from the safe development and commercialisation of ENM technologies.

d. Instrument manufacturers and service providers will benefit from the development of new in situ techniques for tracking nanomaterials in complex environments, allowing them to expand their markets.

e. Improved training for early career researchers: A significant impact of this grant will be generation of highly trained PDRAs people in advanced materials characterisation and environmental science. There is a lack of skilled people in these interdisciplinary areas.

f. Timescale for benefits to be realized: In the short-term any general conclusions about ENM safety are likely to have a relatively rapid impact on health and safety policy. In the longer term, these results may contribute to an understanding of the environmental significance, if any, of ENM structure.
 
Description A significant proportion of the metal-based nano-scale particles in vehicle derived air pollution is attributable to iron oxide.
We are currently testing for signs of CeO2 nanoparticles in cities where bus/coach services use Envirox as an engine catalyst e.g. Bath

From studying sub-micron to nanoscale metal bearing particles found in aerosol samples taken in the city of Jeddah it was determined that industrial facilities were producing metal (not metal oxide) particles which were depositing onto stone and mortar building surfaces. The particles were subsequently oxidising with an associated volume expansion which was causing a hydraulic jacking of micro-crevices in the stone leading to premature degradation. The source of the metal particles was determined by using advanced elemental analysis to determine the composition and trace it back (forensically) to a specific facility. A thesis has now been published and recommendations for legislative change on air pollution limits and types has been submitted to the Saudi Ministries of Environment and Health as well as the Saudi Commission for Tourism and National Heritage.
Exploitation Route There is a growing link between air pollution and neutral illnesses e.g. dementia. Our research corroborates that of others, who have seen nano-iron oxide particles in the finest particle size fractions of air pollution in UK cities (this is well established).
Sectors Agriculture, Food and Drink,Environment,Healthcare,Transport

 
Description Recommendations on air pollution to the Saudi Ministry of Health and Saudi Commission for Tourism and National Heritage
Geographic Reach Africa 
Policy Influence Type Implementation circular/rapid advice/letter to e.g. Ministry of Health
 
Description Fahed Aloufi - Saudi Government PhD in the role of nano-metal aerosols in the degradation of historic building materials
Amount £80,000 (GBP)
Organisation Government of Saudi Arabia 
Sector Public
Country Saudi Arabia
Start 03/2016 
End 10/2019
 
Description I!4 beamtime at the Diamond Light Source - Interactions of engineered nanomaterials with green algae for improved prediction of their ecotoxicity
Amount £38,400 (GBP)
Funding ID BI21294-1 
Organisation Diamond Light Source 
Sector Private
Country United Kingdom
Start 01/2019 
End 01/2019
 
Title High Speed AFM 
Description Utilisation of the NERC funded High Speed Atomic Force Microscopy (HSAFM) capability at Bristol to provide assay of nanoparticle samples. HSAFM has proven very suitable for analysis of size and shape of NPs extracted from environmental samples onto sample substrates (glass or silicon wafers). 
Type Of Material Improvements to research infrastructure 
Year Produced 2015 
Provided To Others? Yes  
Impact No notable impact as yet but the HSAFM technique is showing increasing capability to accelerate research in both materials science and genomics research. 
 
Description Collaboration with Plymouth Marine Laboratory 
Organisation Plymouth Marine Laboratory
Country United Kingdom 
Sector Academic/University 
PI Contribution As a result of developing the HSAFM instrument we have linked with PML to help them set up the new NERC genomics facility. The HSAFM will be a core novel capability of this facility and the collaboration will be strengthened by a joint studentship starting in September 2016.
Collaborator Contribution We helped them become aware of HSAFM for genomics research as a valuable new tool which is both faster and cheaper than the current leading standard (PCR) technology.
Impact The collaboration is multi-disciplinary and has also stared to expand into marine surveying technologies.
Start Year 2015
 
Description Collaboration with the MRI Tsukuba, Japan 
Organisation Meteorological Research Institute
Country Japan 
Sector Public 
PI Contribution We have visited the MRI in October 2016 to establish a partnership in relation to metal-oxide nano-sized particles in air pollution. Working directly with Professor Yashuito Igarashi we are undertaking a transfer of samples and researchers to coordinate research on nanomaterial pollution cause by vehicles.
Collaborator Contribution The have responded with a visit to the UK and have provided us with engineering drawings and build details for the construction of a particle impactor - a device used to sample nano-pollution in the air. We have since purchased such a device for the NERC programme and are using it in central Bristol.
Impact We have yet to make a joint publication as the relationship is relatively juvenile
Start Year 2016
 
Description University of Jeddah 
Organisation Jeddah University
Country Saudi Arabia 
Sector Academic/University 
PI Contribution Providing support in determining metal aerosol pollution in the city of Jeddah and its role in accelerating the degradation of ancient (protected) buildings.
Collaborator Contribution A PhD student (Fahed Aloufi) has been fully funded by the Saudi Government plus (1) Access to sites in Jeddah for sampling and (2) provision of historic air quality data and samples for the city of Jeddah.
Impact None as yet because the project is still ongoing
Start Year 2016