Assessment of the environmental acceptability of potential artificial reef materials using two ecotoxicity tests: Luminescent bacteria and sea urchin embryogenesis

Artificial reefs built by 3D printing: Systematisation in the design, material selection and fabrication

“…In a recent study on leaching and bioassays (inhibition of luminescence and sea urchin embryogenesis) carried out on mortars used for this research, it was concluded that cement mortars presented better leaching behaviour than geopolymer mortars, and that mortars with the use of marine shells presented low environmental acceptance, probably due to the degradation of the organic matter adhered to the shells [63]. These behaviours seem to be unrelated to the biomass results obtained in Fig.…”

Sustainable And Bioengineered Concrete For Armor Units Of Low-Crested Structures

“…For example, the ecological additive used to construct Antifer armor units, mostly based on calcium and silica minerals with 10% of pozzolans, which allows reduction of pH of concrete from 12.5-13.5 (pH of standard concrete) to 9-10.5 Perkol-Finkel, 2015, Kenny andOfer Rozovsky, 2023). The addition of organic materials, such as shell or oyster wastes can also lower the pH of concrete surface and potentially encourage settlement of engineering species such as bivalves (Perkol-Finkel and Sella, 2014), though toxic effects have been found in concretes containing shells, probably due to the decomposition of organic matter attached to the shells (Santos et al, 2023).…”

“…The most investigated cements in the literature are CEM III (slag cements), of which some advantages have already been presented in section 2. These are: (1) increase durability of concrete due to its microstructure after hydration (Boukhelf et al, 2022), (2) increase early biological colonization of concrete due to its lower alkalinity compared to Portland cement (Natanzi et al, 2021), which provides a better substrate for attachment and growth of marine organisms (Rupasinghe et al, 2024), (3) fulfill inert landfill limits in ecotoxicological analysis, from which CEM III/B 32.5 N-SR is recommended for use in artificial reefs (Santos et al, 2023), (4) contain statistically lower amounts of metal released in controlled leaching experiments compared to concrete containing pulverized fly ash or Portland cement (McManus et al, 2018).…”

“…Limestone and glass sand (0-0.3 mm) used as a substitute for 30% sand also showed good mechanical concrete properties to construct artificial reefs (Boukhelf et al, 2022), with better bio-colonization response observed after two years in glass sand concrete than limestone concrete. Crushed glass sand from broken car windshields, used as recycled fine aggregate to partially replace limestone sand in cement mortars, showed high environmental acceptability as artificial reef material while concrete containing shells showed the highest toxic effect (Santos et al, 2023). Proposals for use of local materials to construct artificial reefs include fine marine sediments dredged from ports, limited to 12.5% of the concrete mix to ensure integrity of mechanical properties (Achour et al, 2019), and sea sand as substitute of fine aggregates of concrete mixes (Rupasinghe et al, 2024).…”

Eco-Toxicity Assessment of Industrial By-Product-Based Alkali-Activated Binders Using the Sea Urchin Embryogenesis Bioassay

“…In addition, this test has been regularly used to assess complex environmental matrices, such as contaminated dredged marine sediments (Bonaventura et al, 2021;Carballeira et al, 2012;Khosrovyan et al, 2013;Volpi Ghirardini et al, 2005). This species has also recently been used in toxicity tests of artificial reefs (Santos et al, 2023), wastewater treatment plant effluents (Mijangos et al, 2020), emerging contaminants (Asnicar et al, 2020), microplastic-associated contaminants (di Natale et al, 2022;Trifuoggi et al, 2019) and leachates of microplastic particles (Oliviero et al, 2019;Rendell-Bhatti et al, 2021).…”