Plastic are synthetic polymers widely used in the modern daily life in a wide range of applications from e.g. packaging, building and construction, household, as well as consumer products. Plastics have however become a global environmental threat as an anthropogenic pollution to the marine environment and plastics ubiquitous existence in oceans and seas are in the last decade well documented. Although there are a growing number of literatures in the last two decades that has improved our understanding about the sources, fate and impacts of microplastics in the marine environment, the knowledge is today still in its infancy due to a lack of consistency as there is no standardized definition of microplastics in terms of physical (upper and lower limits in size, shape, density, colour etc) and chemical attributes (polymeric content, solubility etc). The present research focus on the shipping industry and the blue economy according to 1) provide a critical overview of the present knowledge and proposed definitions of microplastics within the scientific and regulatory community, 2) classify types of marine coatings used on merchant vessels on scheduled and non-scheduled maintenance, including a methodology to calculate the paint consumption by the world merchant fleet, 3) provide a meta-analysis study of the current knowledge on microplastic emissions from marine coatings within the scientific and regulatory communities from a risk assessment perspective and 4) develop a cost- benefit analysis of hull coatings to test the energy efficiency technology against CO2 emissions, as well to review if regulations or commercial incentives drive stakeholders behaviors of their choice of coatings.