Harmonized protocols for surveying and monitoring litter, plastics and microplastics - UPSTREAM project approach

Plastic pollution is a diverse contaminant that represents a continuum of properties, from macro scale litter, down to micro and nanoplastic particles, as well as the leachable compounds associated with such plastics. As such no single analytical technique can monitor “plastics” in the environment, and the region of this continuum targeted for monitoring in the Horizon Europe project UPSTREAM is dependent on the technology under development at each of the demonstration sites in the project and the analytical techniques available across the partners. A total of five demonstration sites connecting seven rivers, feeding into five sea basins are to be investigated in the UPSTREAM project. Of these demonstration sites, four technologies associated with wastewater treatment works are investigated whilst the fifth site is the Danube River itself in Serbia. At each demonstration site, either litter, microplastics, leachable compounds associated with plastics, or a combination of these are the target of monitoring. Given the diversity of analytes, locations and institutions required to achieve the monitoring goals in the project, it was essential that standards are used where available, and harmonisation of methods is encouraged where such standards do not exist. There are four critical areas for harmonisation when considering monitoring in the environment: sample collection, sample preparation, sample analysis, as well as data analysis and interpretation. Taking each of the major analytes for monitoring, these aspects of harmonisation are considered, standard operating procedures collected, and agreement reached for recommendations for harmonisation across methodologies. The ambition is to allow evaluation of demo sites themselves but also between sites.