By MARTA E. DOBROWOLSKA, MSc, PhD
Microplastics are defined as particles of insoluble macromolecular polymer with a dimension between 1 nm and 5 mm. Common applications of microplastics include personal care products and laundering chemicals, though other sources include tyre abrasion and degradation products of plastic bottles. Typically, the polymers found are polystyrene, polypropylene, polyester and polyethylene. In agriculture, a discussion has started whether the polymers used in seed treatment products should be considered microplastics and what the potential consequence of that labelling would be.
During the past few years it has been recognised that the pollution of plastic and the concentration of microplastics has significantly increased in surface waters and the oceans. This could negatively impact the marine environment in which it has been found that microplastics bioaccumulate inside a wide variety of organisms.
This emerging issue has led to increased public interest and pressure on decision makers to address this matter. Recent regulatory actions include a ban of single-use plastic by 2021 by the European Parliament as well as a proposal for the restriction of intentionally added microplastics to the environment being worked on by the European Chemical Agency (ECHA).
In July 2018 the European Chemical Agency published a letter on substance identification and the potential scope of a restriction on the uses of microplastics. In it, they defined the substance and steps the Agency will take to understand the key unresolved issues.
At the end of 2018, ECHA had requested the input of various industry bodies such as the European Seed Association (ESA) and European Chemical Industry Council (CEFIC). After receiving this information, ECHA published a “proposal for a restriction” in January 2019. Stakeholders were able to provide feedback by 20th September 2019. Risk assessment committee draft and socio-economic analysis draft opinion should be ready early 2020 and the Entry Into Force (EIF) of the restriction, if adopted, would be in the course of 2021 with not yet known transition periods. Exact timelines are still unclear at this point in time.
Currently in Europe, polymers are mainly regulated by REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals) and CLP (Classification, Labelling and Packaging of Substances and Mixtures). All polymers are exempt from registration and evaluation under REACH but still need to follow CLP guidance.
Chemical and seed treatment companies bring a wide range of seed treatment products to market which have been optimised to comply with the low dust levels in Europe and to retain any plant protection products on the seed. In case of a potential restriction of the use of polymers for seed applications such as plant protection products, film coatings, encrustments and pellets, most formulations will have to be redeveloped. It is to be seen whether alternative microplastic-free formulations will be able to match existing performance (e.g. required dust levels) and have comparable seed safety. Currently, it is not yet known which tests have to be passed to classify a formulation as “microplastic-free”. Considering the time and effort needed to develop alternatives as well as have those registered, a significant transition period will be required.