Biotechnology and Biological Sciences Doctoral Training Programme

Plants on the Pill: Presence and impact of pharmaceutical pollutants and enzymes in wastewater when used for irrigation of crops


Lab rotation project description

Water is the commodity in agriculture and food security. The quality of the water used in agriculture and food production/processing informs on the quality of the products obtained. This project will focus on the increasing use of treated wastewater as a source for irrigating crops. The wastewater treatment process was never designed to remove pollutants (e.g. pharmaceuticals, steroid hormones and metals) and so treated wastewater will contain these chemicals.

The question is what impact does these pollutants have on crop growth and development?

For the rotation project, maize plants will be grown in large rhizoboxes and treated with pharmaceuticals found in wastewater (carbamazapine – a sodium channel regulator and tramadol - one role is interaction with GABA receptors, which is also important in plant abiotic stress responses). Students will measure root growth rates, shoot growth rates. Using 15N stable isotopes students will feed roots of each species with labelled ammonium to determine nitrogen uptake is affected by the pharmaceuticals. Above and below ground biomass will be measured and some above ground physiology measurements such as chlorophyll and stress pigments will be measured with SPAD and DUALEX meters.

This rotation will also introduce students to the different approaches that underpin the linked PhD project:

  • understand the impact of pharmaceuticals in wastewater on plant growth and development of plants including root-shoot signalling and adaptive responses
  • determining the pharmaceutical load in a wastewater and the distribution of these contaminants in plant tissues and soil
  • standard parameters for determining water/soil quality including pH, biochemical oxygen demand, dissolved oxygen

Given time and interest, the students will also have the opportunity to be trained in identifying the enzymes present in the wastewater and plant tissues. Enzymes are inherent to wastewater and plants. Which enzymes and how much is present will inform on the biotransformation potential to remediate these contaminants, as well as inform on how the plant functions. Does the use of wastewater for irrigation influence the enzymatic portfolio of the plant and how that plant is able to function?

Fact file

Research theme

Agri-Food Security


Engineering / Biosciences / NIAB


LR1, LR2, LR3


2nd supervisor

BBSRC Doctoral Training Partnerships

Linked PhD Project Outline

This project focuses on water in agriculture and food security. Water is integral - from provision of suitable quality water for crop production which in turn produces wastewater, to treatment of wastewater produced from animal husbandry.

Global water stress and climate change is driving tighter water cycles and reuse including directly administering treated effluent, risking pollutants such as pharmaceuticals, steroid hormones and metals transferred to crops via root uptake.

The project aim is to understand how tighter water cycles and resulting water quality, impacts on plant growth and development through evaluating pharmaceutical drug load and impacts to the soil and whole plant. If we are to become a water efficient planet, understanding the effects of these pollutants on plant growth is necessary for crop, food security and human health.

The full project could be any combination of expertise from the three partners combining crop species (Rasmussen, SB and Else, NIAB-EMR) to study the impact of pharmaceuticals in wastewater, crops and soil (Gomes, UP) on the whole plant physiology. Plant material collected from each experiment will also be analysed for pharmaceutical levels in different tissues. Combining plant physiology, phenotyping, mathematical modelling, and novel algorithm development with high-level chemical analytics, the student will determine which and how wastewater components (e.g. pharmaceutical drugs, hormones, metals) affect plant growth and development at different scales, from cell to ecosystem.

There are many groups looking at water availability and the effect of drought or floods on crop growth, but water quality is a significant factor in improving water efficiency and crop quality. Maintaining food security and crop resilience will require increasing use of wastewater for irrigation. The pollutant load from water reuse has yet to be evaluated for impact on plant growth, which may also affect pollutant loads in food but may also have positive effects on plant physiology as some compounds affect calcium channels, central to nutrient transporter activity, and others are antibiotics which may alter the soil microbial environment and/or act as selection drivers for antimicrobial resistance. Plant response also has the potential for use as a biological ‘indicator’ - a readily available analytical tool for soil pollutant loads, compared to off-line and expensive chemical analysis.

Opportunities will also be available for collaborating with a University in Mexico studying the influence of pollutant loading in wastewater and use of wastewater irrigation on crop uptake, growth and development.

Triangle project - Yes


Biotechnology and Biological Sciences Doctoral Training Programme

The University of Nottingham
University Park
Nottingham, NG7 2RD

Tel: +44 (0) 115 8466946