Nahum Ashfield
PhD Researcher

Profile

Biography

Nahum is a PhD researcher with an interest in the fate and uptake of pharmaceutical chemicals in agricultural soils and the impacts this has in terrestrial environments. Encompassing soil science, ecotoxicology, environmental chemistry and terrestrial ecology, Nahum’s research aims to increase the current understanding of pharmaceutical behaviours in agricultural systems.

Prior to starting his PhD Nahum completed a BSc in Environmental Science at the University of York, with his dissertation project focusing on nutrient pollution in rivers and its influence on phytoplankton communities. Following this Nahum went on to work as a research associate in herbicide research and development for Syngenta, where he found his interest in the relationships between the agricultural industry the environment. Nahum is excited to utilise his experience in soil science, ecotoxicology and the agricultural industry to shed some new light in this area of research during his PhD.

Career

• 2022-Present: PhD Environmental Science (University of York)
• 2021-2022: Research Associate, Weed Control Biology (Syngenta)
• 2018-2021: BSc Environmental Science (University of York)

Research

Overview

Pharmaceuticals undoubtably play a crucial role in society treating both human and animal medical conditions. As a result of this widespread use, substances are transported to the environment through excretion and their subsequent presence in wastewater and manures. Research in recent decades has focused on exposure in the aquatic environment and identifying the risks of this exposure to organisms and ecosystems. However, evidence of pharmaceutical presence and persistence in the terrestrial environment as a consequence of sewage sludge and manure amendments to agricultural soils, in addition to irrigation with reclaimed water, has exemplified the need to further our understanding of pharmaceutical behaviours in terrestrial systems. 

New active pharmaceutical ingredients now undergo environmental risk assessments during the registration process. However, the environmental impacts of a significant proportion of the 1000+ legacy pharmaceuticals in use globally have not been assessed.  As part of the IMI (Innovative Medicines Initiative) PREMIER project this PhD project aims to prioritise pharmaceutical substances likely to reach terrestrial ecosystems, with the potential to present ecological hazards. Experimental studies will subsequently investigate pharmaceutical behaviours in soils and uptake into soil dwelling organisms, addressing the extent to which substances may pose a threat to terrestrial organisms at higher trophic levels. The ambition is that this will help in providing a method to predict the impacts of legacy pharmaceuticals in the terrestrial environment. 

Supervisors

1. Professor Alistair Boxall
2. Dr Rosie Lennon 

Funding

This Project is funded by the IMI Prioritisation and Risk Evaluation of Medicines in the Environment (PREMIER) Project.