미세플라스틱의 건강 피해 저감 연구 = A Study on Risk Management of Microplastics

다국어 초록 (Multilingual Abstract)

Ⅰ. Background and Objectives
□ Background and need
ㅇ Due to the increasing volume of microplastics used over the last several decades, there are concerns that continued use of microplastics will have consequences unless regulations are put in place. There is a need to investigate the sources and release of microplastics to examine their potential impact on the environment.
ㅇ Recently, the number of studies on microplastics have been increasing, but scientific evidence on microplastics’ impact remains lacking. Big data research is required to combine and analyze the abundance of studies, and careful consideration is needed in devising a risk assessment methodology to scientifically assess the impacts of microplastics.
ㅇ Some countries have established regulations for microbeads, and the European Chemicals Agency (ECHA) is planning to expand regulations on the use of microplastics that are intentionally added. A method of microplastics management by source and product group that takes the characteristics of microplastics into consideration should be prepared.
□ Research objectives for the project duration (3 years, 2019 - 2021)
ㅇ Confirm the sources of primary and secondary microplastics and estimate some product groups’ release into the environment
ㅇ Design a risk assessment methodology for microplastics
ㅇ Suggest reduction and management plans on the risk of microplastics by source and product group
ㅇ Establish a foundation for a microplastics research-related information platform
□ Research objectives and major content of research in 2019 (the first year)
ㅇ Review basic status of microplastics-related investigations, data collection, and policy design directions
ㅇ Major research content of the first year
- Estimation of some product groups’ release of microplastics into the environment
- Analysis of latest research results related to environmental pollution
- Analysis of previous studies on exposure and impact
- Analysis of domestic and international regulations
- Selection of priority target materials for macroplastics management
- Suggestions for microplastic management policies
Ⅱ. Estimation of Sources and Release of Microplastics
□ Sources of microplastics
ㅇ Primary microplastics
- Summarized as personal care products such as cosmetic products, detergents such as laundry detergents, medicinal products or medical devices, agriculture and horticulture, chemicals used in the oil and gas sector, construction materials and the construction industry, paints, coatings, and inks
ㅇ Secondary microplastics
- Produced through use of products (wear and tear): Particles released by worn tires, microfibers released during the washing of clothes, loss of pellets during production and transportation, weathering of agricultural mulching films, road peeling, microplastics relased by building and ship paints, etc.
- Post-use (marine plastic wastes, macro plastics): Disposal of used plastics into open water, carriage via floodwater, disposal of fishing gear such as ropes, nets, and buoys and other waste from seafaring vessels
□ Estimation of microplastic relaese
ㅇ The use and release of primary microplastics
- Domestic production and polymer content were estimated for the six product groups, including paints and detergents.
- The estimated polymer content of domestically-produced paint products was 414,076 tons/year at minimum, and 552,102 tons/year at maximum, averaging 483,089 tons/year.
- The total annual production of detergent products estimated ― based on the replies to surveys of targeted companies ― was approximately 266,968 tons/year, and among them, the estimated polymer content was 126.4 tons/year at minimum and 12,045.1 tons/year on average.
ㅇ Release estimation results of secondary microplastics caused by tire wear
- The total release of secondary microplastics caused by tire wear particles was estimated by applying the tire wear particle emission coefficient to the domestic automobile model. The result was 49,228 to 55,007 tons/year (51,118 tons/year).
Ⅲ. Research and Analysis of Environmental Pollution
□ The status of environmental pollution has typically involved the investigation of shallow seawater layers and research on oceanic deepwater and tidal flats are insufficient.
□ Compared to the marine environment sector, there is a lack of research on pollution in the terrestrial environment sector. Especially, research on soil and the atmosphere is highly insufficient, and there are only a small number of studies on microplastic concentrations in surface soil and the distribution of microplastics in the atmosphere.
□ With respect to research on the status of environmental pollution, there is a problem whereby large variations exist between researchers in terms of sampling tools, analytical methods employed, and base units used in concentration calculations.
Ⅳ. Analysis of Previous Studies on Exposure and Impacts
1. Emissions, fate and transport
□ Research on the inflow, fate, and transport of microplastics in the environment has been concentrated on the marine environment, and therefore research on the terrestrial environment is very limited.
2. Biomagnification
□ It is known that microplastics move through the food chain. However, other research has shown conflicting results regarding whether movement in the foodweb leads to bio-concentration of microplastics and microplastic-associated organic pollutants. This appears to be an ongoing debate.
3. Exposure
□ Because microplastics are detected in soil and freshwater organisms as well as in seawater organisms, it is estimated that exposure to microplastics is occurring at a broad scale across the ecosystem.
ㅇ Human exposure occurs mainly through ingestion and inhalation, and microplastics have been detected in fish, shellfish, shrimp, salt, beer, honey, sugar, mineral water, tap water, and even human feces. Therefore, there is concern regarding the impact of microplastic exposure on human digestive organs.
ㅇ The issue of exposure and effect, which considers risk assessment methods is expected to be discussed more vigorously if more studies on the quantitative evaluation of human exposure are conducted.
4. Impacts
□ Physical/chemical impacts
ㅇ The role of microplastics as carriers of plasticizers/hydrophobic contaminants is an issue of major concern, but studies which have provided evidence of this are lacking.
ㅇ The ingestion of microplastics by aquatic organisms seems to be species-specific, and it is known that as the particle size of microplastics decreases, both ingestion rates and accumulation in an organism increase while the survival rate decreases.
ㅇ The majority of research focuses on experimental studies, but research should reflect environmental concentrations.
□ Toxic effects
ㅇ In general, studies focus on aquatic organisms. In particular, studies on marine organisms confirmed effects on breeding, growth, reproduction, filtration, and breathing at the individual level, and effects on oxidative damage, GST enzyme activation, lipid metabolism, genotoxicity, and immune response at the molecular level.
ㅇ In freshwater species, mortality, development, feeding, and reproduction problems were observed at the individual level, and effects on oxidative damage, metabolic gene expression, digestive enzymes, and neurons were observed at a molecular level.
ㅇ Little research exists on toxic mechanisms, and research targeting soil systems is even less understood.
□ Human Effects
ㅇ While studies on food exposure have been mainly conducted on fish and shellfish, toxic effects through food ingestion have not been confirmed. However, there are discussions that the effects vary depending on human cell types and the characteristics of microplastic particles.
ㅇ The possibility of exposure to airborne microplastics has been raised, and there are concerns of health damage to people who are occupationally exposed or have compromised lung functions. In addition, cases of respiratory effects associated with occupational exposure to microfibers have been confirmed.
ㅇ Potential human health effects raised by previous studies include increased inflammation, microplastic particle size-related toxicity, toxicity of absorbed chemicals, and disruption of the intestinal microbiome. The most interesting issue in regards to health effects is the transport of microplastics through the cell barrier.
ㅇ Recently, interest has been focused on the health effects of plastic additives, but studies on this issue remain scarce.
Ⅴ. Trends in Domestic and International Regulation of Microplastics
1. Autonomous activities inducing the market phase-out of microplastics
□ In some countries, industry is proactively reducing the use of microplastics with government encouragement and there are participatory programs led by a broad range of stakeholders operated based on initiative activities.
2. Regulatory policies through legislation, etc.
□ In eight countries, the policies for primary microplastics mainly take the form of restriction legislated at the national level. The following nations have some regulation in place: the USA and Canada in North America, Sweden, Italy, France, and the UK in Europe; New Zealand in Oceania and South Korea in Asia.
□ A case study on the pan-government dimension of regulation: European Chemicals Agency (ECHA)
ㅇ The ECHA is currently reviewing a proposal to restrict the use of primary plastics by including them among the restricted materials of REACH (Registration, Evaluation, Authorization and Restriction of Chemicals), currently being enforced in EU countries.
ㅇ Regulations through restricted material registration of primary microplastics consist mainly of merchandising restrictions in the market, labelling requirements, and reporting requirements. They are to be immediately applied to cosmetic products, detergents, and maintenance products containing microbeads without delay and in the cases of remaining cosmetic product types, medical devices, detergents, maintenance products and agricultural and horticultural products, a grace period will be given.
ㅇ Although some exception clauses are included for paints and coatings, the regulations deal with a broad range of microplastics. Therefore, if the corresponding proposal passes, regulations on the use of primary microplastics are expected to be strengthened in not only the EU member countries but also globally.
Ⅵ. Selection of Priority Targets for Macro-plastics Management
□ In this study, we prioritized “macro-plastics (plastics released post-use)” because there is a lack of research on sources and quantitative estimates of volumes, which would help us determine policy priorities for management.
ㅇ We consider released volumes using coast monitoring data, chemical and physical risks, recycling value, existing regulations, necessity of additional management, etc. to determine management priorities.
ㅇ EPS buoys were selected as a priority target among marine sources, and bottle caps made of PP were targeted among land sources.
Ⅶ. Conclusion and Policy Suggestion
□ As a result of this study, difficulties in policy design are expected because the size, scope and definition of microplastics are not clear. Therefore, policy-based agreement should be arranged for a conceptual definition of microplastics.
□ Information regarding the domestic production of microplastics, the basic status of which is needed for relevant policy design, is highly insufficient, and therefore efforts are needed to estimate the use and release of microplastics by all sources.
□ Chemical-related regulation fatigue is high in the industrial sector in South Korea, and various policy alternatives and incentives should be developed to encourage cooperation from industry.
□ Considering the situation in South Korea, where the rights of executing microplastics-related policies are distributed, designing systematic policies by preparing a pan-governmental decision-making organization is presently necessary.