#EnvChem2020: Chemistry of the Whole Environment Research
Laura Alcock
Edwards Ltd
laura.alcock@edwardsvacuum.com
ECG Bulletin January 2021
Edwards Ltd
laura.alcock@edwardsvacuum.com
ECG Bulletin January 2021
This one-day conference was jointly organised by the ECG, and UK Branch of the Society for Environmental Toxicology and Chemistry (SETAC).
Intended to take place in York, #EnvChem2020 was our first online event. Despite technical challenges such as the reorganisation of face-to-face posters, this successful event allowed participation from far-spread delegates. The format involved nine speakers delivering 15 minute presentations, and a key-note. Posters were delivered as flash (three minute) presentations in “breakout” rooms.
Main presentations
Michelle Bloor chaired the first session, introducing Dr Nadine Borduas-Dedekind (ETH Zurich). Dr Borduas-Dedekind’s presentation Reactive oxygen species (ROS), including singlet oxygen, production within irradiated aqueous organic aerosols began with a Zurich sunset, which represented a variety of atmospheric chemistries including photochemistry, cloud types, and industrial emissions. Dr Borduas-Dedekind covered the formation of singlet oxygen, exploring its in-laboratory generation using organic aerosols. Analysis was achieved by filtration and dissolution. Probe decay was used to measure singlet oxygen over time and liquid chromatography for total organic carbon. Quantum yields were calculated to normalise steady state concentrations using liquid chromatography–UV/visual light spectroscopy, which compared well to aquatic environments. The proceeding discussion highlighted the importance of singlet oxygen in the atmosphere, which is produced in high concentrations, compared to other ROS, and shows higher quantum yields.
Ayushi Priyam (Deakin University), next presented Investigation for ecosafety and transformation of phosphorus based nanofertilizers by using Caenorhabditis elegans as a terrestrial model. The presentation focused on the effects of nano-fertilisers on C. elegans. Uptake of nano-hydroxyapatite was monitored by fluorescent isothermal titration calorimetry (ITC) tagging. Different methods of producing the nano-fertiliser resulted in different shapes and sizes of the products and, whilst all formulations had a minimal effect on the survival of organisms, rock phosphate showed the greatest impact. The study determined that nanofertiliser formulations had a greater biocompatibility than bulk rock phosphate; thus, provided the correct compound is selected for the application, they cause less detriment to the environment than bulk fertilisers.
Jamie Harrower (Glasgow Caledonian University), closed the first session with a presentation on on Monitoring antibiotics in urban river environments using in-situ calibrated Polar Organic Chemical Integrative Samplers (POCIS), grab sampling and analysis by SPE-LC-MS/MS. POCIS samples were collected at accessible points upstream and downstream of a wastewater treatment plant (WWTP) in Scotland and were calibrated over a 12-day period. Factors affecting function were identified and, where possible, mitigating actions taken. Monitoring demonstrated that the WWTP effluent contained high concentrations of pharmaceutical compounds, especially penicillin, and highlighted potential contamination by landfill sites. Proposed further work includes comparison to river sediments, using fugacity modelling (see page 29).
Dr Rowena Fletcher-Wood chaired the second session and introduced the keynote speaker Professor Iseult Lynch (University of Birmingham) who spoke on Multi-generational assessment of nanomaterials (NMs) toxicity: Particle ageing reduces toxicity and ageing effect of the NMs on D. magna. Water fleas (D. magna) rely on an eco-corona, composed of a wide range of biomolecules, that affect what can bind or be combined within it. A selection of nanomaterials were introduced to the environment. Agglomeration of the particles increased uptake by D. magna, as no significant uptake of particles < 50 nm in diameter was observed. The impact of nanomaterial exposure on the brood, generational timelines and brood survival rates were explored. Initial exposure to uncoated TiO2 prevented reproduction entirely. The exposure concentration was reduced, resulting in successful reproduction, but significantly lower brood survival rate. Dissolution and accumulation of the nanomaterials, and the growth and reproduction of D. magna, including changes in morphology, were also discussed. Accelerated ageing was observed. Gene expression changes resulted from nanomaterial exposure, and protein corona differences were examined. Professor Lynch concluded that the effects of aged nanomaterials on the D. magna were significantly less severe than that of new materials. Natural organic matter reduced the surface energy of the nanomaterials. The presence of nanomaterials did not simply result in oxidative stress in the D. magna, but also in accelerated ageing.
John Collins chaired the first afternoon session and introduced Oluseun Sunday Olubode (University of Ibadan), who presented on Allelopatic effects of Celosia trigyna L. on germination and growth of three widely cultivated African indigenous vegetables in Ibadan, southwest Nigeria. Dr Olubode outlined how solutions extracted from the shoots and roots of the weed (C. trigyna) were prepared across a range of concentrations (0, 12.5, 25, 37.5, 50 g/L) and applied to 30 seeds per plant. Germination rate was then assessed 2, 4 and 6 days after sowing. Germination was found to be inhibited by treatment, whilst the shoot extract stimulated germination. Plumule and radicle growth were also assessed, with the shoot extract promoting plumule growth and inhibiting that of radicles.
Alexandra Richardson (King's College London) then presented Using LC-MS, passive sampling and predictive modelling to understand the occurrence and environmental impact of contaminants in a London urban river system. There was a particular focus on contaminants of emerging concern (CECs; pharmaceuticals, pesticides and personal care products), the seasonal changes in these contaminants, and predicting the bioconcentration factor in invertebrates by machine learning. Ms Richardson outlined the methods of sample collection during summer and winter sampling campaigns. Sample extracts were prepared and analysed by reverse-phase liquid chromatography coupled to a quadrupole-time of flight (Q-TOF) method and a reversed-phase biphenyl coupled with a rapid quadrupole (MS/MS) method – particularly for water samples. All samples were compared to a set of 164 standards and 34 CECS were found in the winter water samples, compared to 53 in the summer water samples. 58 CECs were found in the winter passive sampler extracts, compared to 67 in the summer. A four-layer perceptron-based machine learning model for predicting the bioconcentration factor in Gammarus pulex was applied. Following training, optimisation and testing, the model achieved an R2 performance of 0.98 and 0.91 for verification and blind tests, respectively and externally validated using experimental data from animals. The different numbers of CECs found in Thames river water between winter and summer were attributed to differences in the resident population of London during the two periods. The most prevalent compounds were selected for bioaccumulation testing.
Aoife Quinlivan (University of Nottingham) finished the session by presenting Preventing the rising tide of AMR: Utilising stable water MOFs to remove antibiotics from wastewater. She identified anthropogenic water pollution as a primary contributor to antimicrobial resistance (AMR) within the environment and explored the stability and effectiveness of metal-organic frameworks (MOFs) for removing CECs from water. Current WWTPs are not equipped to deal with antimicrobial compounds. MOFs consist of metal anodes connected by organic linkers, giving them high structural porosity. They have a large surface area, resulting in a high capacity for adsorption; their linkers can also be functionalised, allowing for specification and selectivity to prevent removal of desirable compounds from the water, whilst maximising removal of the target compounds. Ms Quinlivan presented criteria for industrial viability and functionality, with an overview of the specific MOF – MIL-100 (Fe), synthesised by microwave irradiation and then characterised. She outlined MIL-100 (Fe) stability as a function of time, temperature and quantity of adsorbent used to remove ciprofloxacin from water. Following each test, the MOF was centrifuged and dried. Functional groups were identified and pH monitored over time, giving a rapid initial drop. Stability was affected by seasonal temperature, which may affect industrial applications. There was a logarithmic relationship between the relative masses of the MOFs and the pH of the water matrix. Water containing ciprofloxacin was dosed with MIL-100 and analysed, at incremental time periods, by liquid chromatography-mass spectroscopy (LC-MS). Over time, the concentration of the antibiotic compounds within the water samples decreased.
Dr Tom Sizmur chaired the final session of the day and introduced Jize Jiang (University of Edinburgh), who presented on Developing a climate-dependent model of ammonia emissions from agriculture discussing human impact on the nitrogen cycle, through agricultural emissions of ammonia. Fertiliser usage accounts for over 85% of all atmospheric release of ammonia in western countries. Temperature and water interactions significantly impact ammonia volatilisation, calling into question official ammonia emissions values, based on the calculation of these figures from statistical data with limited analysis of meteorological data. Mr Jiang’s model aimed at providing more reliable estimates of ammonia emissions, considering meteorological effects like temperature, relative humidity and pH, and temporal variations. Chicken farming was used as a model, requiring the collection of detailed ammonia emissions data. The model considered global emissions of ammonia from chicken farms and calculated that the highest emissions would occur in tropical areas of high temperature and humidity. Conversely, hot, dry areas were predicted to produce much lower emissions. Mr Jiang and his colleagues next plan to quantify emissions from other livestock sources and develop a bi-directional exchange model. His answers to questions highlighted the fact that the most significant factor in agricultural ammonia emissions is human management.
Alberto Celma (University Jaume I of Castelló) then delivered a presentation on The combination of bioanalyses with ion mobility high-resolution mass spectrometry for an enhanced environmental screening. His project combined in vitro bioassays with chemical analyses to identify the presence of organic contaminants within coastal lagoons across Spain’s Mediterranean coast. High resolution mass spectrometry (HRMS) and ion mobility separation (IMS) were employed for wide-scope analysis, and prior separation of the analyte. Coupling these techniques provides huge scope and resolution, but unwieldy datasets. The team also carried out a series of eight bioassays. Results were combined with target and non-target analysis by IMS-HRMS. The different toxicity profiles of the samples allowed identification of a range of organic contaminants present in the lagoons’ surface waters, as well as identifying a potential influence on anomalous data, in the form of WWTP effluent.
Intended to take place in York, #EnvChem2020 was our first online event. Despite technical challenges such as the reorganisation of face-to-face posters, this successful event allowed participation from far-spread delegates. The format involved nine speakers delivering 15 minute presentations, and a key-note. Posters were delivered as flash (three minute) presentations in “breakout” rooms.
Main presentations
Michelle Bloor chaired the first session, introducing Dr Nadine Borduas-Dedekind (ETH Zurich). Dr Borduas-Dedekind’s presentation Reactive oxygen species (ROS), including singlet oxygen, production within irradiated aqueous organic aerosols began with a Zurich sunset, which represented a variety of atmospheric chemistries including photochemistry, cloud types, and industrial emissions. Dr Borduas-Dedekind covered the formation of singlet oxygen, exploring its in-laboratory generation using organic aerosols. Analysis was achieved by filtration and dissolution. Probe decay was used to measure singlet oxygen over time and liquid chromatography for total organic carbon. Quantum yields were calculated to normalise steady state concentrations using liquid chromatography–UV/visual light spectroscopy, which compared well to aquatic environments. The proceeding discussion highlighted the importance of singlet oxygen in the atmosphere, which is produced in high concentrations, compared to other ROS, and shows higher quantum yields.
Ayushi Priyam (Deakin University), next presented Investigation for ecosafety and transformation of phosphorus based nanofertilizers by using Caenorhabditis elegans as a terrestrial model. The presentation focused on the effects of nano-fertilisers on C. elegans. Uptake of nano-hydroxyapatite was monitored by fluorescent isothermal titration calorimetry (ITC) tagging. Different methods of producing the nano-fertiliser resulted in different shapes and sizes of the products and, whilst all formulations had a minimal effect on the survival of organisms, rock phosphate showed the greatest impact. The study determined that nanofertiliser formulations had a greater biocompatibility than bulk rock phosphate; thus, provided the correct compound is selected for the application, they cause less detriment to the environment than bulk fertilisers.
Jamie Harrower (Glasgow Caledonian University), closed the first session with a presentation on on Monitoring antibiotics in urban river environments using in-situ calibrated Polar Organic Chemical Integrative Samplers (POCIS), grab sampling and analysis by SPE-LC-MS/MS. POCIS samples were collected at accessible points upstream and downstream of a wastewater treatment plant (WWTP) in Scotland and were calibrated over a 12-day period. Factors affecting function were identified and, where possible, mitigating actions taken. Monitoring demonstrated that the WWTP effluent contained high concentrations of pharmaceutical compounds, especially penicillin, and highlighted potential contamination by landfill sites. Proposed further work includes comparison to river sediments, using fugacity modelling (see page 29).
Dr Rowena Fletcher-Wood chaired the second session and introduced the keynote speaker Professor Iseult Lynch (University of Birmingham) who spoke on Multi-generational assessment of nanomaterials (NMs) toxicity: Particle ageing reduces toxicity and ageing effect of the NMs on D. magna. Water fleas (D. magna) rely on an eco-corona, composed of a wide range of biomolecules, that affect what can bind or be combined within it. A selection of nanomaterials were introduced to the environment. Agglomeration of the particles increased uptake by D. magna, as no significant uptake of particles < 50 nm in diameter was observed. The impact of nanomaterial exposure on the brood, generational timelines and brood survival rates were explored. Initial exposure to uncoated TiO2 prevented reproduction entirely. The exposure concentration was reduced, resulting in successful reproduction, but significantly lower brood survival rate. Dissolution and accumulation of the nanomaterials, and the growth and reproduction of D. magna, including changes in morphology, were also discussed. Accelerated ageing was observed. Gene expression changes resulted from nanomaterial exposure, and protein corona differences were examined. Professor Lynch concluded that the effects of aged nanomaterials on the D. magna were significantly less severe than that of new materials. Natural organic matter reduced the surface energy of the nanomaterials. The presence of nanomaterials did not simply result in oxidative stress in the D. magna, but also in accelerated ageing.
John Collins chaired the first afternoon session and introduced Oluseun Sunday Olubode (University of Ibadan), who presented on Allelopatic effects of Celosia trigyna L. on germination and growth of three widely cultivated African indigenous vegetables in Ibadan, southwest Nigeria. Dr Olubode outlined how solutions extracted from the shoots and roots of the weed (C. trigyna) were prepared across a range of concentrations (0, 12.5, 25, 37.5, 50 g/L) and applied to 30 seeds per plant. Germination rate was then assessed 2, 4 and 6 days after sowing. Germination was found to be inhibited by treatment, whilst the shoot extract stimulated germination. Plumule and radicle growth were also assessed, with the shoot extract promoting plumule growth and inhibiting that of radicles.
Alexandra Richardson (King's College London) then presented Using LC-MS, passive sampling and predictive modelling to understand the occurrence and environmental impact of contaminants in a London urban river system. There was a particular focus on contaminants of emerging concern (CECs; pharmaceuticals, pesticides and personal care products), the seasonal changes in these contaminants, and predicting the bioconcentration factor in invertebrates by machine learning. Ms Richardson outlined the methods of sample collection during summer and winter sampling campaigns. Sample extracts were prepared and analysed by reverse-phase liquid chromatography coupled to a quadrupole-time of flight (Q-TOF) method and a reversed-phase biphenyl coupled with a rapid quadrupole (MS/MS) method – particularly for water samples. All samples were compared to a set of 164 standards and 34 CECS were found in the winter water samples, compared to 53 in the summer water samples. 58 CECs were found in the winter passive sampler extracts, compared to 67 in the summer. A four-layer perceptron-based machine learning model for predicting the bioconcentration factor in Gammarus pulex was applied. Following training, optimisation and testing, the model achieved an R2 performance of 0.98 and 0.91 for verification and blind tests, respectively and externally validated using experimental data from animals. The different numbers of CECs found in Thames river water between winter and summer were attributed to differences in the resident population of London during the two periods. The most prevalent compounds were selected for bioaccumulation testing.
Aoife Quinlivan (University of Nottingham) finished the session by presenting Preventing the rising tide of AMR: Utilising stable water MOFs to remove antibiotics from wastewater. She identified anthropogenic water pollution as a primary contributor to antimicrobial resistance (AMR) within the environment and explored the stability and effectiveness of metal-organic frameworks (MOFs) for removing CECs from water. Current WWTPs are not equipped to deal with antimicrobial compounds. MOFs consist of metal anodes connected by organic linkers, giving them high structural porosity. They have a large surface area, resulting in a high capacity for adsorption; their linkers can also be functionalised, allowing for specification and selectivity to prevent removal of desirable compounds from the water, whilst maximising removal of the target compounds. Ms Quinlivan presented criteria for industrial viability and functionality, with an overview of the specific MOF – MIL-100 (Fe), synthesised by microwave irradiation and then characterised. She outlined MIL-100 (Fe) stability as a function of time, temperature and quantity of adsorbent used to remove ciprofloxacin from water. Following each test, the MOF was centrifuged and dried. Functional groups were identified and pH monitored over time, giving a rapid initial drop. Stability was affected by seasonal temperature, which may affect industrial applications. There was a logarithmic relationship between the relative masses of the MOFs and the pH of the water matrix. Water containing ciprofloxacin was dosed with MIL-100 and analysed, at incremental time periods, by liquid chromatography-mass spectroscopy (LC-MS). Over time, the concentration of the antibiotic compounds within the water samples decreased.
Dr Tom Sizmur chaired the final session of the day and introduced Jize Jiang (University of Edinburgh), who presented on Developing a climate-dependent model of ammonia emissions from agriculture discussing human impact on the nitrogen cycle, through agricultural emissions of ammonia. Fertiliser usage accounts for over 85% of all atmospheric release of ammonia in western countries. Temperature and water interactions significantly impact ammonia volatilisation, calling into question official ammonia emissions values, based on the calculation of these figures from statistical data with limited analysis of meteorological data. Mr Jiang’s model aimed at providing more reliable estimates of ammonia emissions, considering meteorological effects like temperature, relative humidity and pH, and temporal variations. Chicken farming was used as a model, requiring the collection of detailed ammonia emissions data. The model considered global emissions of ammonia from chicken farms and calculated that the highest emissions would occur in tropical areas of high temperature and humidity. Conversely, hot, dry areas were predicted to produce much lower emissions. Mr Jiang and his colleagues next plan to quantify emissions from other livestock sources and develop a bi-directional exchange model. His answers to questions highlighted the fact that the most significant factor in agricultural ammonia emissions is human management.
Alberto Celma (University Jaume I of Castelló) then delivered a presentation on The combination of bioanalyses with ion mobility high-resolution mass spectrometry for an enhanced environmental screening. His project combined in vitro bioassays with chemical analyses to identify the presence of organic contaminants within coastal lagoons across Spain’s Mediterranean coast. High resolution mass spectrometry (HRMS) and ion mobility separation (IMS) were employed for wide-scope analysis, and prior separation of the analyte. Coupling these techniques provides huge scope and resolution, but unwieldy datasets. The team also carried out a series of eight bioassays. Results were combined with target and non-target analysis by IMS-HRMS. The different toxicity profiles of the samples allowed identification of a range of organic contaminants present in the lagoons’ surface waters, as well as identifying a potential influence on anomalous data, in the form of WWTP effluent.
Qingzhe Zhang (Institut national de la recherche scientifique; INRS) provided the final presentation of the day in which he identified environmental pollution and energy demand as two primary threats to human life and proposed the use of photocatalysts to address both in his presentation Broadband solar harvesting via plasmonic and heterojunction nanostructures for environmental and energy applications. Mr Zhang explained that photocatalysis could directly harvest and utilise solar energy and addressed the challenges of this application: many photocatalysts only interact with ultraviolet (UV) and blue light, leaving much of the incident solar energy unused. The focus of the study was increasing solar energy usage for remediation of environmental samples. Plasmonic gold (Au) particles were incorporated into a semiconductor to improve photocatalytic efficiency using the “size-tuneable” localised surface plasmon resonance effect of the gold nanoparticles (AuNPs). These were then tested in the remediation of organic contaminants in wastewater samples. Lanthanide-doped NaYF4 (NYF) coupled with graphitic carbon nitride (g-C3N4) AuNPs were stable and demonstrated improved photocatalytic activity, using UV, visible, and near infrared (NIR) light to degrade organic pollutants. AuNP-loaded hierarchical TiO2 spheres also showed “strikingly high activity and selectivity” for the reduction of 4-nitrophenol to 4-aminophenol with visible light radiation. However, as Mr Zhang highlighted, gold and rare-earth metals are expensive. To improve efficiency and cost-effectiveness, and reduce environmental toxicity, a 0D/2D heterojunction was constructed, based on NIR-responsive quantum dot (QD) loaded g-C3N4 nanosheets. These exhibited the highest recorded photocatalytic activity in wastewater treatment.
Breakout room presentations
Dr Aaron Schultz (University of Alberta) presented Trouble Relaxing: polyacrylic acid coated nanoparticles impair blood vessel physiology. This was the first study to use an ex vivo perfusion method, mimicking circulation, coupled with dual-wire myography to study the effects of nanoparticles on the circulatory system. Iliac arteries from cane toads were perfused with polyacrylic acid-coated TiO2 nanoparticles, which inhibited Ach-mediated vasodilation by approximately half, attributable to damage to the epithelial layer of the lumen in the vessels.
Dr Adam Peters (WCA Environment) presented two talks. The first; Implementation of environmental quality standards for bioavailable metals: Compliance assessment, discussed the challenges faced by regulators, including numerous locations, additional resources and expertise, and the measurement of parameters other than bioavailability of metals. The second, Demonstrating the reliability of bio-met: A simple bioavailability tool for determining compliance with Environmental Quality Standards (EQS) for metals, introduced a simplified model, based on a Biotic Ligand Model for implementation of bioavailability-based EQS in European freshwaters. In a suitability study, over 80% of the predictions fell within a factor of three of the experimental findings and 99% of predictions were within a factor of two. Further validation using a larger set of European natural water samples, demonstrated reliability “over a broad range of water chemistry conditions”.
Dr Aaron Schultz (University of Alberta) presented Trouble Relaxing: polyacrylic acid coated nanoparticles impair blood vessel physiology. This was the first study to use an ex vivo perfusion method, mimicking circulation, coupled with dual-wire myography to study the effects of nanoparticles on the circulatory system. Iliac arteries from cane toads were perfused with polyacrylic acid-coated TiO2 nanoparticles, which inhibited Ach-mediated vasodilation by approximately half, attributable to damage to the epithelial layer of the lumen in the vessels.
Dr Adam Peters (WCA Environment) presented two talks. The first; Implementation of environmental quality standards for bioavailable metals: Compliance assessment, discussed the challenges faced by regulators, including numerous locations, additional resources and expertise, and the measurement of parameters other than bioavailability of metals. The second, Demonstrating the reliability of bio-met: A simple bioavailability tool for determining compliance with Environmental Quality Standards (EQS) for metals, introduced a simplified model, based on a Biotic Ligand Model for implementation of bioavailability-based EQS in European freshwaters. In a suitability study, over 80% of the predictions fell within a factor of three of the experimental findings and 99% of predictions were within a factor of two. Further validation using a larger set of European natural water samples, demonstrated reliability “over a broad range of water chemistry conditions”.
Dr Balal Yousaf (University of Science and Technology of China) presented Role of biochar application on environmental transformation and fate of engineered nanoparticles (ENPs) in soil-plant system. Biochar material was produced and added to soils to immobilise TiO2 ENPs and reduce bioaccumulation of Ti in wheat plants. Testing showed that biochar cut the Ti concentration in wheat tissues by two thirds and the transfer rate reduced by 50% when plants were exposed to the highest concentration of Ti ENPs (1000 mg L-1).
Dr Ben Maskrey (Cefas) presented Seasonal occurrence of pharmaceuticals and related compounds in bivalve molluscs from England and Wales, reporting the bioaccumulation of active pharmaceutical compounds in oysters and molluscs collected from six sites across at four points throughout the year. Antidepressants, particularly sertraline, were identified. Seasonal and site-specific fluctuations were observed.
Bilikis Folarin (University of Lagos) delivered Antibiotic residues in chicken muscles and eggs purchased from poultry farm and local market in Lagos, Nigeria. This study investigated the presence of ciprofloxacin, oxytetracycline and tetracycline, used for food hygiene purposes in poultry farms. All three compounds were present at concentrations above the maximum residue limit (MRL) set by the Food and Agriculture Organisation of the United Nations. Ciprofloxacin was found to be highest in thigh meat, oxytetracycline and tetracycline in eggs.
Brian Durham (University of Birmingham) presented Carbon dioxide/water/ice equilibria at atmospheric partial pressures. Following a conceptual model of crystal growth, modified to account for gas hydrate formation, the project team intend to continue to grow “carbon dioxide frost” in vitro, utilising pure reagents to obtain empirical data on carbon dioxide molecule behaviour at the ice phase boundary.
Celine Moreira (Polymateria Limited) delivered Biodegradable plastics: a compatible approach to solving short- and long-term associated risk of plastic contamination in countries of the Global South. In this talk, the scale, challenges and hazards associated with plastic waste, including types and overall availability of biodegradable plastics were presented.
Christopher Howick (INOVYN Chlorovinyls Limited) discussed; The importance of nomenclature in the understanding of chloroalkanes: linking measured chlorination level and chain length found in matrices and articles to primary raw materials, His presentation linked the difficulty of manufacturing chloroalkanes to appropriate standards, due to their high isomeric content. Developments in the analysis of these compounds has led to updated standards and regulations.
Chris Hughes (Ricardo Energy & Environment), spoke on Advances in bioavailability science and application to chemical regulation, and discussed the role of bioavailability in determining the risks presented by chemicals within the environment. He also discussed the risks associated with failing to consider the fate of chemicals or the concentrations that they can reach in the environment. This can cause under- or over-estimation of the potential risks, hazards and exposure.
David Brown (Ricardo Energy & Environment) discussed Challenges and learnings from biodegradation testing of complex and difficult test substances. Challenges include unknown or variable composition, complexity of reaction products, biological materials, and testing limitations. Hydrocarbons, for example, are unsuitable. Development and validation are needed, especially since false negatives could have significant regulatory, classification and, as a result, environmental consequences.
Bilikis Folarin (University of Lagos) delivered Antibiotic residues in chicken muscles and eggs purchased from poultry farm and local market in Lagos, Nigeria. This study investigated the presence of ciprofloxacin, oxytetracycline and tetracycline, used for food hygiene purposes in poultry farms. All three compounds were present at concentrations above the maximum residue limit (MRL) set by the Food and Agriculture Organisation of the United Nations. Ciprofloxacin was found to be highest in thigh meat, oxytetracycline and tetracycline in eggs.
Brian Durham (University of Birmingham) presented Carbon dioxide/water/ice equilibria at atmospheric partial pressures. Following a conceptual model of crystal growth, modified to account for gas hydrate formation, the project team intend to continue to grow “carbon dioxide frost” in vitro, utilising pure reagents to obtain empirical data on carbon dioxide molecule behaviour at the ice phase boundary.
Celine Moreira (Polymateria Limited) delivered Biodegradable plastics: a compatible approach to solving short- and long-term associated risk of plastic contamination in countries of the Global South. In this talk, the scale, challenges and hazards associated with plastic waste, including types and overall availability of biodegradable plastics were presented.
Christopher Howick (INOVYN Chlorovinyls Limited) discussed; The importance of nomenclature in the understanding of chloroalkanes: linking measured chlorination level and chain length found in matrices and articles to primary raw materials, His presentation linked the difficulty of manufacturing chloroalkanes to appropriate standards, due to their high isomeric content. Developments in the analysis of these compounds has led to updated standards and regulations.
Chris Hughes (Ricardo Energy & Environment), spoke on Advances in bioavailability science and application to chemical regulation, and discussed the role of bioavailability in determining the risks presented by chemicals within the environment. He also discussed the risks associated with failing to consider the fate of chemicals or the concentrations that they can reach in the environment. This can cause under- or over-estimation of the potential risks, hazards and exposure.
David Brown (Ricardo Energy & Environment) discussed Challenges and learnings from biodegradation testing of complex and difficult test substances. Challenges include unknown or variable composition, complexity of reaction products, biological materials, and testing limitations. Hydrocarbons, for example, are unsuitable. Development and validation are needed, especially since false negatives could have significant regulatory, classification and, as a result, environmental consequences.
Godswill Tesi (Federal University of Petroleum Resources) spoke on Organochlorine pesticides (OCPs) in agricultural soils of Southern Nigeria: Spatial distribution, source identification, ecotoxicological and human health risks assessment. His study investigated 20 OCPs in 18 soil samples from six locations. Total concentrations ranged from 5.8 to 395 ng g-1, typically Chlordane > HCHs > DDTs > Endosulfan > Endrin > Aldrin > Dieldrin.
Harrison Frost (University of Surrey) discussed The Adsorption of aqueous metal(loid)s by microplastic fibres: Preliminary findings. Adsorption of 12 metals and metalloids onto polyester fibres were initially investigated, with 90% removal of Cd. Adsorption rates showed poor repeatability. Antimony leaching from the fibres was observed and attributed to the use of SbO3 as a catalyst during polyester production.
Harrison Frost (University of Surrey) discussed The Adsorption of aqueous metal(loid)s by microplastic fibres: Preliminary findings. Adsorption of 12 metals and metalloids onto polyester fibres were initially investigated, with 90% removal of Cd. Adsorption rates showed poor repeatability. Antimony leaching from the fibres was observed and attributed to the use of SbO3 as a catalyst during polyester production.
Iain Wilson (WCA Environment) discussed Addressing the challenges associated with applying bioavailability-based standards for metals in freshwaters. He highlighted the complexity of bioavailability models and the low availability of the required parameters as the primary difficulties. When combined with bio-met, a European industry-funded database initiative, he delivered new regional and ecologically relevant standards for Zn in French surface waters.
James Dinsley (University of Manchester) discussed Uranium and lead uptake and transfer within plant-fungal symbioses. This study investigated the use of plants and fungi for bioremediation of abandoned mining sites contaminated by heavy metals and naturally occurring radioactive materials (NORMs), with a focus on plant-microbe interactions. The primary concern is the risk of transfer and bioaccumulation.
Janine Elliott (Scottish Environmental Protection Agency) presented Chemical screening of surface waters – A proof of concept study. She selected 13 locations, including agricultural, urban, forestry and semi-natural typologies, whereupon 135 non-target compounds were identified and 99 quantified, including some previously unobserved. Most were pharmaceuticals and their metabolites. Patterning was attributed to chemical usage. The tool shows potential for use in incidents where the source of pollution is unknown.
Dr Kirit Wadhia (National Oilwell Varco) delivered Risk based assessment and regulatory drivers, where he discussed the variation in risk endpoints by different oil and gas producers, based on the assumptions and input parameters used (only aligned in their use of chemical guidance values). He proposed a global regulatory framework to enable uniform risk assessment and comparable outcomes between companies.
Lorraine Hutt (Environment Agency) spoke on Identifying emerging contaminants in the environment: Development of the Environment Agency’s PEWS scheme, proposing a system to allow prioritisation of emerging contaminants for regulatory management based on potential risks to wildlife and the environment (the new Prioritisation and Early Warning System (PEWS)). The system considers the levels and patterns of chemical use, occurrence in the environment, potential hazards, evidence of impact, and the level of confidence in data. An appeal was made for people willing and able to provide additional data.
Megan Griffiths (Ricardo Energy and Environment) presented Bioavailability, complex substances and overall persistence (BCOP): three themes to deliver a step-change in persistence assessments – Overview of a CEFIC-LRI project (ECO52). She proposed significant improvements to guidance, especially for difficult-to-assess substances by considering bioavailability, providing guidance for complex substances, and incorporating overall persistence using multimedia fate models.
Michael Eze (University of Göttingen), discussed Metagenomic insight into a diesel-degrading consortium for the bioremediation of diesel fuel contaminated sites. His potential solution to expensive and “environmentally unfriendly” traditional methods for remediation of fuel contaminated land and soils was plant-microbe symbiosis, which proved a cost-effective, eco-friendly bioremediation method. The study has also provided insight into the genes involved in diesel fuel degradation by plants and microbes.
Shivender Singh Saini (Central University of Himachal Pradesh) presented A simple, self ensembled, chitin based sample preparation approach for trace analysis of 17β-estradiol in water. The method presented is simple, cost-effective and eco-friendly. Testing indicated good linearity in the 0.05 – 20 ng/mL range and a lower detection limit of 0.02 ng/mL. It is hoped that the method can be applied to other emerging contaminants in the future.
James Dinsley (University of Manchester) discussed Uranium and lead uptake and transfer within plant-fungal symbioses. This study investigated the use of plants and fungi for bioremediation of abandoned mining sites contaminated by heavy metals and naturally occurring radioactive materials (NORMs), with a focus on plant-microbe interactions. The primary concern is the risk of transfer and bioaccumulation.
Janine Elliott (Scottish Environmental Protection Agency) presented Chemical screening of surface waters – A proof of concept study. She selected 13 locations, including agricultural, urban, forestry and semi-natural typologies, whereupon 135 non-target compounds were identified and 99 quantified, including some previously unobserved. Most were pharmaceuticals and their metabolites. Patterning was attributed to chemical usage. The tool shows potential for use in incidents where the source of pollution is unknown.
Dr Kirit Wadhia (National Oilwell Varco) delivered Risk based assessment and regulatory drivers, where he discussed the variation in risk endpoints by different oil and gas producers, based on the assumptions and input parameters used (only aligned in their use of chemical guidance values). He proposed a global regulatory framework to enable uniform risk assessment and comparable outcomes between companies.
Lorraine Hutt (Environment Agency) spoke on Identifying emerging contaminants in the environment: Development of the Environment Agency’s PEWS scheme, proposing a system to allow prioritisation of emerging contaminants for regulatory management based on potential risks to wildlife and the environment (the new Prioritisation and Early Warning System (PEWS)). The system considers the levels and patterns of chemical use, occurrence in the environment, potential hazards, evidence of impact, and the level of confidence in data. An appeal was made for people willing and able to provide additional data.
Megan Griffiths (Ricardo Energy and Environment) presented Bioavailability, complex substances and overall persistence (BCOP): three themes to deliver a step-change in persistence assessments – Overview of a CEFIC-LRI project (ECO52). She proposed significant improvements to guidance, especially for difficult-to-assess substances by considering bioavailability, providing guidance for complex substances, and incorporating overall persistence using multimedia fate models.
Michael Eze (University of Göttingen), discussed Metagenomic insight into a diesel-degrading consortium for the bioremediation of diesel fuel contaminated sites. His potential solution to expensive and “environmentally unfriendly” traditional methods for remediation of fuel contaminated land and soils was plant-microbe symbiosis, which proved a cost-effective, eco-friendly bioremediation method. The study has also provided insight into the genes involved in diesel fuel degradation by plants and microbes.
Shivender Singh Saini (Central University of Himachal Pradesh) presented A simple, self ensembled, chitin based sample preparation approach for trace analysis of 17β-estradiol in water. The method presented is simple, cost-effective and eco-friendly. Testing indicated good linearity in the 0.05 – 20 ng/mL range and a lower detection limit of 0.02 ng/mL. It is hoped that the method can be applied to other emerging contaminants in the future.
Shweta Gelhout (The Energy and Resources Institute) delivered Phytotoxicity assessment of mycosynthesized iron oxide nanoparticles on Oryza sativa (Asian Rice) in different soil types. Iron oxide nanoparticles (nFe3O4) were synthesised with a verified biogenic approach. The role of the nitrate reductase enzyme during synthesis was investigated and the effect of biogenic nFe3O4 on O. sativa and plant-growth-promoting bacteria assessed. An increase in germination rate (30%), wet (55%) and dry biomass (40%) and shoot length (10%) were observed compared to bulk controls for all soil types.
Rose Alani (University of Lagos) spoke on Concentrations profiles and exposure risks of atmospheric polycyclic aromatic hydrocarbons (PAHs) in Lagos, Nigeria, a study into spatial and temporal variation in PAHs in the air, and possible exposure risks. The results ranged from residential levels of 28.82 ng/m3 to industrial levels of 111.93 ng/m3. A seasonal industrial trend was observed, with highest values in the dry season.
Rose Alani (University of Lagos) spoke on Concentrations profiles and exposure risks of atmospheric polycyclic aromatic hydrocarbons (PAHs) in Lagos, Nigeria, a study into spatial and temporal variation in PAHs in the air, and possible exposure risks. The results ranged from residential levels of 28.82 ng/m3 to industrial levels of 111.93 ng/m3. A seasonal industrial trend was observed, with highest values in the dry season.
Saer Samanipour (University of Amsterdam) presented A novel high-resolution mass spectrometry toolbox for unravelling the chemical exposome, outlining a collection of open-source tools to improve and simplify non-target analysis workflows. These tools were tested on complex environmental samples including WWTP influent and sludge and were found to outperform commonly used methodologies.
Rachel Schwartz-Narbonne (Newcastle University) discussed Detection of methanotrophic bacteria in peatlands through a novel high temperature gas chromatographic analysis method for bacteriahopanepolyols. Bacteriohopanetetrol is produced by an aerobic peatland methanotoph. Its concentrations were analysed to identify that M. palustris may have a significant role in methane fixing and storage in peatlands.
Rebecca Rae (University of Edinburgh) delivered Remediation of hexavalent chromium and selenium using the mineral ettringite. She discussed the sequestration of hexavalent chromium and selenium anions from wastewater through incorporation into the column material ettringite. A competitive mineral phase was also identified. Next steps include the introduction of competitive ions and recycling metals via ettringite decomposition at low pH.
Phillip Colyer (University of Portsmouth) discussed A chemical and ecological assessment into elemental loading from Ford Crossing in Ashdown Forest, Sussex, United Kingdom. Biomonitoring and chemical analyses assessed harmful contaminants from road surface and vehicular run-off into waterways. Chromium, lead and zinc were elevated at one sample site. Elevation of zinc and magnesium were observed following rain, demonstrating waterway sensitivity.
Rachel Schwartz-Narbonne (Newcastle University) discussed Detection of methanotrophic bacteria in peatlands through a novel high temperature gas chromatographic analysis method for bacteriahopanepolyols. Bacteriohopanetetrol is produced by an aerobic peatland methanotoph. Its concentrations were analysed to identify that M. palustris may have a significant role in methane fixing and storage in peatlands.
Rebecca Rae (University of Edinburgh) delivered Remediation of hexavalent chromium and selenium using the mineral ettringite. She discussed the sequestration of hexavalent chromium and selenium anions from wastewater through incorporation into the column material ettringite. A competitive mineral phase was also identified. Next steps include the introduction of competitive ions and recycling metals via ettringite decomposition at low pH.
Phillip Colyer (University of Portsmouth) discussed A chemical and ecological assessment into elemental loading from Ford Crossing in Ashdown Forest, Sussex, United Kingdom. Biomonitoring and chemical analyses assessed harmful contaminants from road surface and vehicular run-off into waterways. Chromium, lead and zinc were elevated at one sample site. Elevation of zinc and magnesium were observed following rain, demonstrating waterway sensitivity.
Preston Akenga (University of Plymouth) spoke on Uptake of antiviral pharmaceutical compounds in lettuce. Reclaimed wastewater and bio-solids are commonly used as agricultural soil amendments. Four antiviral active pharmaceutical ingredients were identified, with concentrations up to 3450 ng g-1 (dry). Uptake was higher than environmentally significant exposure levels and was affected by the hydrophobicity, pH and concentration in the exposure solution.
Peng Zhang (University of Birmingham) discussed Nanomaterial transformation and phytotoxicity: Implications for food safety and application in agriculture. Two studies investigated plant-species dependent transformation of CeO2 nanoparticles and the phytotoxicity and transformation of graphene nanoparticles in rice plants.
Peng Zhang (University of Birmingham) discussed Nanomaterial transformation and phytotoxicity: Implications for food safety and application in agriculture. Two studies investigated plant-species dependent transformation of CeO2 nanoparticles and the phytotoxicity and transformation of graphene nanoparticles in rice plants.
Philippa Kearney (University of Bath) presented Removal of endocrine disruptor bisphenol A from water. She addressed the need for eco-friendly management, proposing an electro-chemical oxidative polymerisation method, with proven concept and optimised electrode surface treatment. An extraction and fluorescence based quantitative analysis method was developed as a cheap, rapid method for quantification in ocean samples.
Olumide Emmanuel Akinrinade (University of Birmingham) delivered review on Status of flame retardants, polychlorinated biphenyls, and polycyclic aromatic hydrocarbons in air and indoor dust in Africa. The focus was on trends of persistent organic pollutants (POPs). The primary source of the principle POPs in Africa are obsolete electronics and imported waste treatment.
Olumide Emmanuel Akinrinade (University of Birmingham) delivered review on Status of flame retardants, polychlorinated biphenyls, and polycyclic aromatic hydrocarbons in air and indoor dust in Africa. The focus was on trends of persistent organic pollutants (POPs). The primary source of the principle POPs in Africa are obsolete electronics and imported waste treatment.
Paschal Iniaghe (University of Africa) presented Concentrations and human health risk assessment of polychlorinated biphenyls (PCBs) in canned sardines available in the Nigerian Market. The concentrations across 15 brands were up to 926 ng kg-1. Adult exposure was quantified up to 232 ng kg-1 bw day-1. Both carcinogenic and non-carcinogenic risks were identified associated with human consumption of these sardines.
Neville Llewellyn (Thermo Fisher Scientific) discussed The first global reconnaissance of organic pollutants in tap water. This involved non-target monitoring of 69 sites in 51 countries globally, representing the entire socio-economic spectrum. 1 mL samples were assessed via Q Exactive Orbitrap mass spectrometry. Contamination, including illicit drug compounds were more prevalent in developed locations. DEET was widespread, but high in sub-Saharan Africa.
Nina J. Schleider (Imperial College London) spoke on Bioavailability of trace metals in atmospheric particulate matter. The study investigated four particle fractions in air from Beijing. Zinc, cadmium, manganese and arsenic were detectable at high concentrations in the very mobile fraction and lead and copper in the mobile fraction. Toxic elements originate primarily from anthropogenic sources.
Miguel A. Gomez-Gonzalez (Imperial College London) delivered Intermediate speciation changes and spatially resolved transformation of ZnO nanomaterials within wastewater environments, where he reviewed a new method based on in situ X-ray fluorescence microscopy for observing real-time dissolution and morphological and chemical evolution of ZnO nanorods with 1-3 hour incubation times in influent water and primary sludge form WWTPs. After only an hour in influent water, ZnO nanorods were completely transformed to insoluble zinc sulphide (ZnS).
Moses Ogbaje (University of Kentucky) discussed Production and application of activated carbon sourced from agricultural wastes for water treatment. Results showed significant but varied removal of copper (4.64-98.7%), lead (33.3-100%), and other metals. Activated carbon made from almond fruit had higher removal of copper, zinc and magnesium than activated carbon made from African star apple shells and snail shells.
Symiah Barnett (Aston University) introduced The identification of microplastics using density analysis (page 25), which used affordable, accessible density analysis methods to identify microplastic polymer types. The method used only water, sucrose and ethanol to distinguish eight types of microplastics by their densities. A precise solution preparation protocol was developed. Different types of microplastics float or sink in the different solutions, allowing their identification.
Nina J. Schleider (Imperial College London) spoke on Bioavailability of trace metals in atmospheric particulate matter. The study investigated four particle fractions in air from Beijing. Zinc, cadmium, manganese and arsenic were detectable at high concentrations in the very mobile fraction and lead and copper in the mobile fraction. Toxic elements originate primarily from anthropogenic sources.
Miguel A. Gomez-Gonzalez (Imperial College London) delivered Intermediate speciation changes and spatially resolved transformation of ZnO nanomaterials within wastewater environments, where he reviewed a new method based on in situ X-ray fluorescence microscopy for observing real-time dissolution and morphological and chemical evolution of ZnO nanorods with 1-3 hour incubation times in influent water and primary sludge form WWTPs. After only an hour in influent water, ZnO nanorods were completely transformed to insoluble zinc sulphide (ZnS).
Moses Ogbaje (University of Kentucky) discussed Production and application of activated carbon sourced from agricultural wastes for water treatment. Results showed significant but varied removal of copper (4.64-98.7%), lead (33.3-100%), and other metals. Activated carbon made from almond fruit had higher removal of copper, zinc and magnesium than activated carbon made from African star apple shells and snail shells.
Symiah Barnett (Aston University) introduced The identification of microplastics using density analysis (page 25), which used affordable, accessible density analysis methods to identify microplastic polymer types. The method used only water, sucrose and ethanol to distinguish eight types of microplastics by their densities. A precise solution preparation protocol was developed. Different types of microplastics float or sink in the different solutions, allowing their identification.
Theodore Dibble (SUNY College of Environmental Science and Forestry) delivered Recent advances in understanding mercury redox chemistry. Bromine interactions result in oxidation of Hg, followed by a second radical reaction, usually with NO2 – both reactions take place at lower rates than previous studies indicated. BrHgO· reacts with CO, eventually becoming BrHg·, which reduces Hg(II) to Hg(I), and CO2. The rate of this is constant but uncertain, and appears to be higher than the rate of BrHgO· reacting with CH4 to form BrHgOH. This has a significant effect on Hg redox chemistry.
Vajira Perera (Sri Lanka’s Tertiary and Vocational Education Commission) discussed Development of audit criteria for Water Safety Plan, a brief overview of the WHO Water Safety Plan (WSP) criteria, including the deliberation and decision-making process, detailed hazard identification and risk assessment, routine monitoring, drinking water quality audits, and routine and emergency management procedures.