Do agricultural microplastics undermine food security and sustainable development in developing countries?

Lead Research Organisation: Bangor University
Department Name: Sch of Natural Sciences


THE GLOBAL PROBLEM: The presence of large amounts of plastic in terrestrial, freshwater and marine ecosystems appears almost ubiquitous, with frequent reports of negative impacts of plastics on ecosystem health. This has led to the United Nations Environment Programme declaring plastic pollution as one of the top 10 global environmental problems. The problem of plastic pollution is particularly acute in low and middle-income countries (LMICs) where it is impairing the health and wellbeing of billions of the world's poorest and most vulnerable people. In addition, it is compromising our ability to deliver many of the UN's Sustainable Development Goals (SDG). While much research effort has been spent understanding the behaviour of microplastics in marine systems, the impact of plastics in terrestrial environments, and especially agricultural systems, remains poorly understood. This is surprising considering that 80% of plastics arriving in the oceans were produced, used, and often disposed of on land. It has also led to speculation that it is within terrestrial systems that microplastics might actually be of greatest concern.

THE PLASTIC PARADOX IN LMICs: Over the last 50 years, many governments and overseas aid agencies have actively encouraged the use of plastics within agriculture to promote greater resource use efficiency and food security. The adoption of plastic mulch films in particular, has transformed the livelihoods of millions of smallholder farmers across the world, however, this has been achieved at a large environmental cost. Difficulties in removing plastic from fields, a lack of appreciation for its impact on agroecosystem health, and socioeconomic/practical barriers to its effective disposal have left a plastic pollution legacy that will last for many generations to come. There is therefore an urgent need to critically evaluate the environmental and human health risks posed by these legacy plastics and to devise effective ways and social structures to prevent further accumulation and to try and remediate plastic contaminated fields.

TACKLING THE ISSUE: To address the problem and help deliver tangible solutions, we have brought together a multidisciplinary team of natural and social scientists from 5 contrasting LMICs (China, Egypt, India, Sri Lanka and Vietnam). We chose these 5 countries as this is where the problem of agricultural plastic pollution is most acute and because they are at different stages of tackling the problem. Together, these countries use 3 million tonnes of agricultural plastic film each year covering 25 million hectares of agricultural land. They also span a wide range of climates and possess a range of governance structures which will enable our outcomes to be readily translated to other similar LMICs. Consequently, the overall aim of our research is to quantify the risk that conventional macro-, micro- and nano-plastics pose to the long-term health of agricultural ecosystems. This information will be used to critically evaluate the likely impact of conventional agricultural plastic use on food security and rural livelihoods. In addition, we aim to identify practical, economic, socially acceptable and politically viable solutions to help remediate land contaminated with plastic and prevent further pollution from occurring through lasting behaviour and policy change.

PROJECT LEGACY: Our fundamental approach will be to co-design context-specific, locally-owned interventions to reduce the plastic legacy, while still maintaining sustainable farming practices and livelihoods. It is vital that we generate legacy to ensure that the tools, technology, knowledge and partnerships we develop persist well beyond the project end-date and that the outcomes continue to spread to other LMICs. We have embedded legacy into the fabric of our project. For example we will upskill LMIC researchers, build research capital, create an information portal and design novel decision support tools.


10 25 50

publication icon
Ding F (2021) Does long-term use of biodegradable plastic mulch affect soil carbon stock? in Resources, Conservation and Recycling

Description The GCRF project has conducted extensive research examining the occurrence, behavior, and impacts of microplastics in agricultural soils. A major focus has been understanding the accumulation and degradation of plastic mulch films, a key source of soil microplastics, as well as impacts on soil health and functioning.

Key highlights of the project include:

- Quantifying microplastic accumulation in soils from major vegetable production regions in China after mulch film use. High levels were found, from 1.8 x 104 to 4 x 104 particles per kg soil, indicating accumulation over time. Polyethylene and polypropylene dominated. Regions and mulching methods explained over 30% of contamination variation.

- Assessing impacts of pristine low density polyethylene (LDPE) and polypropylene (PP), as micro- and macro-plastics, in soil-plant mesocosms across a wide concentration gradient spanning 1-50 years worth of plastic mulch film residues. They found negligible impacts at <10 years loading rates, but reductions in plant growth and microbial biomass at higher loadings.

- Studying effects of LDPE microplastics versus biodegradable PLA-PBAT plastic films on fate of nitrogen fertilizer applied to soil-barley mesocosms. LDPE altered soil nitrogen pools and cycling. But limited impacts on plant health suggested functionality thresholds were not crossed even at high loading rates.

- Testing a bioplastic polyhydroxyalkanoate (PHBV) across a broad contamination gradient (0.01-10%) in soil-maize mesocosms. PHBV negatively impacted soil organisms, nutrient availability, plant growth and foliar health. Metabolomics indicated microbial toxicity likely driving observed effects.

- Assessing impacts of polyethylene versus biodegradable PHBV microplastics added at a realistic field rate (100 kg/ha) to a winter barley field trial. No observable effects on crop yield, soil functions or N2O fluxes were found after one cropping cycle. But N2O was reduced with polyethylene microplastics.

- Evaluating long-term plastic mulch film legacy in a >30-year interactive field trial. High macroplastic residues remained in soil surface (up to 6,800 pieces/m2) with abundance 2x higher in fertilized subplots likely due to material entanglements impeding removal. Total microplastics ranged from 2,300-10,600 particles/ kg across 0-100 cm depth profiles.

- Studying simazine herbicide degradation after spiking with polyethylene and PVC microplastics at 1-20% levels. Half-lives increased, likely due to shifts in microbial communities and reduced enzyme activities. Showed combined exposure can impede agrochemical breakdown.

Overall this project has provided novel data on the accumulation, fate and impacts of microplastics in cropland soils, indicating contamination can alter key soil and plant functions under certain conditions. But also illustrates importance of field studies and realistic exposure scenarios when evaluating risks. Their work helps inform guidelines for more sustainable use of plastics in agriculture.
Exploitation Route The project is still ongoing.
Sectors Agriculture

Food and Drink



including Industrial Biotechology

Title LDIR analysis of plastics 
Description generation of new libraries 
Type Of Material Technology assay or reagent 
Year Produced 2023 
Provided To Others? No  
Impact new method for plastics analysis in soil 
Title Nitrous oxide emissions and associated microbial diversity, soil biochemical properties and crop growth and yield from a field trial of winter barley with the addition of microplastics, Abergwyngregyn, UK, 2020-2021 
Description This dataset contains field data on nitrous oxide (N2O) emissions, microbial community composition, crop yield and growth and soil biochemical properties. The field trial consisted of three different treatments of control, conventional microplastic addition and biodegradable microplastic addition where winter barley was grown. The data presented are from field and laboratory measurements. Data was collected by the data authors. The field trial was carried out from September 2020 to July 2021 at Henfaes Field Centre, UK. Research was funded through NERC Grant NE/V005871/1. Do agricultural microplastics undermine food security and sustainable development in developing countries? 
Type Of Material Database/Collection of data 
Year Produced 2022 
Provided To Others? Yes  
Impact Accompanies a paper to be published. 
Description European Bioplastics Conference 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact conference talk
Year(s) Of Engagement Activity 2023
Description Training event Bhopal India 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Study participants or study members
Results and Impact In August 2022, Dr Mondira Bhattacharya from the University of Reading provided a week of training to staff at ICAR-IISS, Bhopal, the India project partner and Government research institute. The training focused on the use of a social survey tool and input into Kobo tool box. The training event included trialling the new skills in the field with farmers and the process helped to increase capacity of researchers at the research institute.
Year(s) Of Engagement Activity 2022
Description Training event at Mansoura University, Egypt 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Study participants or study members
Results and Impact In September 2022 Dr Mondira Bhattacharya and Prof Henny Osbahr visited Mansoura University, Egypt for a week to provide training in the social science tools and visit field locations to pilot the approach. The research team, together with extension and outreach professionals, visited field locations and had the opportunity to engage with farmers who use plasticulture, a business which collects plastic from farmers and recycles, and a plastic producer. The engagement with farmers and the private sector opened a conversation about further information about production of biodegradable plastic and the constraints within the waste management system for agricultural plastics.
Year(s) Of Engagement Activity 2022
Description Vietnam WP4 project workshop 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Study participants or study members
Results and Impact Participants from China, India, Sri Lanka, Egypt and Vietnam met at the Soils and Fertiliser Research Institute, Hanoi, Vietnam, for 3 days from 27 February 2023 to discuss progress in the data collection and preliminary insights from the data analysis for WP4. This component of the research focuses on understanding farmer level perspectives about the use of agricultural plasticulture, challenges for removal and decision making to adopt bioplastic alternatives. The workshop facilitated co-development of the research narratives, agreement on analysis methodology, publication strategy and ways to feed in the learning to other components of the wider research project, including identification of other stakeholders and legacy impact. The meeting also facilitated capacity building through training of research tools and analysis methods and included research staff and PhDs from the countries to participate, in addition to country leads.
Year(s) Of Engagement Activity 2023
Description skills workshop - netherlands 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Postgraduate students
Results and Impact skills workshop on methodology
Year(s) Of Engagement Activity 2024