Recent trends in application of shell waste from mariculture

Today, commercial mollusk farming is an essential component of the global aquaculture industry with a share of 23% of the world's total production and the tendency of continual growth. Small investments and low energy consumption make this production a globally interesting source of cheap and healthy food for the growing population of people on the planet. However, since shells can account for up to 75% of total bivalve body weight, contamination of the ecosystem by bivalve shells is one of the major problems of this industry branch. Seashell waste produced in vast quantities around the globe is often dumped in landfill or the sea. This waste piles up at coastal areas and causes many environmental problems. This paper aims to draw attention to the issues and risks from seashell waste and to discuss the solutions which would potentially be a step towards mitigating the environmental burden. European Union directive has vigorously enforced the development of new technologies that exploit waste as resources and contribute to the concept of sustainable development. In this regard, recent trends in shell waste applications have been reviewed, as novel ideas for reducing the waste accumulation and valorizing of shells to achieve both ecological and economic incentives.