Intentionally added microplastics (tiny solid polymer particles) are included in various chemical products. Like degraded microplastic waste, intentionally added microplastics are of concern because of their potential to impact human and animal health. Regulators worldwide are assessing how to address intentionally added microplastics, with the ECHA classifying them as equivalent to PBT/vPvB (persistent, bioaccumulative, toxic/very persistent, very bioaccumulative) substances and proposing a restriction on their use. Read on to find out how this restriction may affect a range of industries and what actions need to be taken by when.
Microplastics are widely used in a range of products from multiple industries
Microplastics are a common ingredient in many everyday products. From use as exfoliators in cosmetics, antifoaming agents in detergents, seed coatings in agriculture to providing controlled release mechanisms for medicines – microplastics are ubiquitous. According to the ECHA, in 2017, over 51,000 (11,000–63,000) tonnes of microplastics were used intentionally in the EEA, with about 70% (36,000 tonnes) ending up in the environment.1
The potential threat of microplastics to ecosystems and human health is complex, with a lot of uncertainty remaining.2 However, evidence is building to suggest that microplastics are accumulating in the food chain and may present hazard to marine life. They have, therefore, become a pressing concern for many chemical regulators, with the ECHA taking clear action.
Definition of intentionally added microplastic
There is no one globally accepted definition of a microplastic, leading to a lack of consistency in both scientific investigations and worldwide regulatory approaches. Existing definitions vary in relation to both the particle size and the chemical composition, with further complication added by the use of additional terms such as microbeads.
In Europe and the EEA, the ECHA under REACH regulation provides specific definitions for microplastic and microbeads – see Table 1.
Table 1: Microplastic definitions under the proposed REACH restriction1
|Microplastic||A material consisting of solid polymer-containing particles, to which additives or other substances may have been added, and where|
≥1% weight/weight (w/w) of particles have: all dimensions 1 nm ≤ x ≤ 5 mm, or for fibres, a length of 3 nm ≤ x ≤ 15 mm and length to diameter ratio of >3. Polymers that occur in nature that have not been chemically modified (other than by hydrolysis) are excluded, as are polymers that are (bio)degradable.
|Microbeads||A microplastic used in a mixture as an abrasive, i.e. to exfoliate, polish or clean.|
|Polymer||A substance within the meaning of Article 3(5) of Regulation (EC) No 1907/2006 (REACH).|
|Particle||A minute piece of matter with defined physical boundaries (a defined physical boundary is an interface).|
|Polymer-containing particle||Either: a particle of any composition with a continuous polymer surface coating of any thickness or a particle of any composition with a polymer content of ≥1% w/w.|
The ECHA, based on evidence gathered on microplastics, views them as similar to PBT/vPvB substances under Annex XV of REACH.This means thatthere does not need to be an identified hazard for substances containing microplastics to be banned. In the words of ECHA:
“…microplastics should be treated as non-threshold substances for the purposes of risk assessment, similar to PBT/vPvB (persistent, bioaccumulative, toxic/very persistent, very bioaccumulative) substances under the REACH regulation, with any release to the environment assumed to result in a risk.”
The ECHA propose three actions for products containing microplastics:
- A restriction on placing on the market microplastics on their own or in mixtures where their use will inevitably result in releases to the environment, irrespective of the conditions of use. A transitional period, to allow sufficient time for stakeholders to comply with the restriction, is in place for some uses.
- A labeling requirement to minimize inadvertent microplastic release and enhance their appropriate use and disposal.
- A reporting requirement to improve information collection on which to assess potential future risks.
To avoid falling under the restriction, manufacturers and importers of substances containing microplastics must demonstrate that their microplastic is biodegradable. However, as no harmonized framework for testing yet exists, this may prove challenging.
ECHA restriction on intentionally added microplastics
The REACH restriction on microplastics states under paragraph 1 of Annex XV:
“Polymers within the meaning of Article 3(5 )of Regulation (EC) No 1907/2006 shall not, from [entry into force (EiF)], be placed on the market as a substance on its own or in a mixture as a microplastic in a concentration equal to or greater than [0.01]% w/w.”
With many sectors using microplastics as key ingredients, achieving this may be challenging. Therefore, the ECHA provides transition periods and derogations to allow industry time and space to develop alternatives, such as biodegradable polymers.
Derogations under Annex XV
It is possible to apply for derogation under Annex XV for the following situations:
- Substances or mixtures containing microplastics for use at industrial sites.
- Medicinal products for human or veterinary use.
- Substances or mixtures that are regulated in the EU under Regulation (EC) No xxx/xxxx on Fertilising Products
- Substances or mixtures containing microplastics where the microplastic is both
- contained by technical means throughout the whole lifecycle to prevent releases to the environment and
- any microplastic containing wastes arising are incinerated or disposed of as hazardous waste.
- Substances or mixtures containing microplastics where the physical properties of the microplastic are permanently modified when the substance or mixture is used such that the polymers no longer fulfil the Annex XV definition of a microplastic
- Substances or mixtures containing microplastics where the microplastic is permanently incorporated into a solid matrix when used.
Derogated products may still require appropriate labeling and annual reporting, however.
Entry into force (EiF)
The consolidated opinion on the microplastics restriction was published in June 2020, with the final opinion of the Committee for Socio-Economic Analysis (SEAC) expected late 2020, and entry into force (EiF) in 2022. The transition periods vary by industry. For example, restrictions on microbeads in cosmetics comes into place immediately on EiF, but for products like seed treatment this is 5 years post-EIF. See Figure 1 for restriction implementation milestones.
Figure 1: Restriction implementation milestones
Annual microplastic waste released into the environment by sector in the EEA in 2017
Testing the biodegradability of your intentionally added microplastic
To comply with the Annex XV restriction, manufacturers and importers must demonstrate that their microplastic is biodegradable. However, this may be challenging because, as Annex XV states, “…harmonised analytical methods for detecting microplastics in products are yet to be agreed and a framework of test methods and criteria for identifying (bio)degradable ‘microplastics’ will likely require additional research and development to progress beyond the ‘interim’ criteria proposed here.”
Annex XV recommends a tiered testing approach of initial screening followed by higher tier assessments.
Screening tests and higher-tier testing
The recommended screening tests focus on ready biodegradation, enhanced/modified biodegradation with inherent biodegradation and (bio)degradation relevant to a reference material employed for microplastics suspected of being less biodegradable based on their chemical structure.
It is probable that the more advanced screening tests will be required for most microplastics. However, these advanced tests take time – up to 2 years for (bio)degradation relevant to a reference material in soil – so against this context the transition periods do not look particularly generous.
The higher-tier testing recommended in Annex XV requires assessment of the microplastic’s half-life in the most relevant environmental compartment and under conditions representative of where the microplastic will end up. For example, test temperatures of 12°C for fresh/estuarine water and fresh/estuarine water sediment and soil or 9°C for marine water and marine sediment, which reflect EU averages. Annex XV recommends OECD TGs 307, 308 and 309 for higher-tier testing. These are well established for use with chemicals, but pose challenges when assessing biodegradation related to polymers.
Bespoke microplastic testing
Given existing challenges, newer methodologies are being developed and refined with the aim of showing microplastics are not persistent in the environment. While these tests do not show that the substance meets the strict definition of readily or inherently biodegradable, they do demonstrate that, under certain conditions, some plastics are not persistent. However, they do demonstrate that under certain conditions, some plastics are not persistent.
The ECHA Annex XV restriction on microplastic use will impact a wide range of industries from cosmetics to agriculture to medicines. The testing framework to support the new requirements is still evolving, but with EiF looming in 2022, innovation in both product development and biodegradability testing are both ramping up.
ECHA: European Chemicals Agency
EEA: European Economic Area
EiF: entry into force
PBT/vPvB: persistent, bioaccumulative, toxic/very persistent, very bioaccumulative
REACH: Registration, Evaluation, Authorisation and Restriction of Chemicals
SEAC: Committee for Socio-Economic Analysis
- ECHA. Submitted restrictions under consideration. Microplastics. https://echa.europa.eu/restrictions-under-consideration/-/substance-rev/22921/term
- European Commission Scientific Advice Mechanism (SAM) Environmental and Health Risks of Microplastic Pollution. Scientific Opinion 6/2019 (supported by SAPEA Evidence Review Report No. 4). Brussels, 30 April 2019. https://op.europa.eu/en/publication-detail/-/publication/f235d1e3-7c4d-11e9-9f05-01aa75ed71a1/language-en/format-PDF/source-108645429