The lethal effect of hydrotechnical concrete on freshwater Bivalvia

Abstract

Most hydrotechnical buildings under construction demand the concrete mixture to be set directly under water. The main reason for such a procedure is to limit the washing away of the the concrete binding mixture and to increase the efficiency of organisation of work so as to ensure continuity in concreting. The impact on the aquatic environment of recent developments in concrete technology and the use of new components has not yet been established. Natural pebble aggregate containing portland cement and fugacious siliceous ash as a binder was used to prepare BP concrete samples, while concrete marked LB was composed with lightweight aggregate and portland cement as a binder. The aim of this paper was to answer to the question whether hydrotechnical concrete of different compositions (BP and LB) and the technology of setting in a water habitat have any influence on the life condition of commonly occurring Dreissena polymorpha (Mollusca, Bivalvia). The lethal effect of two types of freshly hardening concrete was observed. In the case of LB concrete the lethal outcome for D. polymorpha could be the effect of a considerable increase of electrolytic conduction in the test cultivation. In the case of BP the parameters of electrolytic conductivity and pH did not exceed the values appearing in lakes. The possibility of the occurrence of toxic compounds of D. polymorpha, arising from the reaction of the aquatic / lake environment or the elution of some components should be taken into account. D. polymorpha serves as an indicator of toxicity in the aquatic environment and therefore can be used as a model organism in the analysis of the influence concrete on the natural environment. The results obtained in this study indicate the significant impact of modern chemical composition of concrete on the aquatic environment and the living organisms that cover it. They underline the need for research based on the hydrobiont reaction to the substances used in the natural environment.

Flow cytometric approach to evaluate the impact of hydro-technical concrete compounds’ release to the freshwater microbiome

“…In order to reduce the toxicity of concrete, the cubes were placed in the lake (natural reservoir, about 1500 ha), in the coastal and wave zone, 5 m from the shore, at a depth of 1 m, for 9 months (from September 2016 to June 2017) (Mariak et al, 2018;Wojtasik et al, 2019). After the exposition period, BP cubes were stained with the Rose Bengal sodium salt (Sigma-Aldrich Merck) to determine the spreading of samples by small aquatic organisms and microorganisms.…”

“…Hydro-technical concretes usually contains mineral additives (e.g., fly ash), anti-washout admixtures (AWA), and superplasticizers, e.g., high-range water-reducing admixture (HRWR), increasing the washout resistance of underwater concretes, keeping the water in the concrete mixture to prevent high leaching of cement paste (Heniegal et al, 2015), and providing with high durability (Khayat & Sonebi, 2001). The modified composition of the concretes can be dangerous to living water organisms, e.g., Bivalvia (Wojtasik et al, 2019). The bactericidal effect of some additives like silica-titania-special nanocomposite-and also a positive effect of a waste glass aggregate for bactericidal properties of cement mortars were observed (Chung et al, 2017;Sikora et al, 2017;Wei et al, 2013).…”

“…Thus, the concrete constructions and the addition of different new components to the concrete have an often unknown impact on the aquatic environment. There is very little research related to this issue, e.g., Wojtasik et al who have described the harmful effects of hydro-technical concrete on freshwater Bivalvia (Wojtasik et al, 2019).…”

Influence of selected additives and admixtures on underwater concrete and the environment

“…The preliminary results of the authors' research [22] were published at the 8th International Scientific Conference, Toxic Substances in the Environment Toxe 2017. The aim of the research was to state if there is any influence of hydrotechnical concrete components on survivability of organisms inhabiting concrete elements.…”

“…Parameters of electrolytic conductivity and pH did not exceed the values present in lakes inhabited by that types of organisms. Therefore, the possibility of presence of compounds toxic for Zebra mussel emerging as a result of reaction in aquatic environment (lake) [22][23][24][25] shall be taken into account.…”