The Impact of Metal-Based Nanoparticles Produced by Different Types of Underwater Welding on Marine Microalgae

Underwater wet welding is commonly used in joining pipelines and in underwater construction. Harmful and hazardous compounds are added to many flux-cored wires for underwater welding and cutting, and can have a negative impact on marine life. The specific objective of this study was to evaluate the aquatic toxicity of two suspension samples obtained using welding electrode and flux-cored wire in marine microalgae Attheya ussuriensis and Porphyridium purpureum. Growth rate inhibition, cell size, and biochemical changes in microalgae were evaluated by flow cytometry. The results of the bioassay demonstrated that the suspension obtained after welding with electrode had an acute toxic impact on diatomic microalgae A. ussuriensis, and both tested suspensions revealed chronic toxicity in this microalga with a 40% growth rate inhibition after exposure to 40-50% of prepared suspensions for 7 days. Red algae P. purpureum revealed tolerance to both suspensions caused by exopolysaccharide covering, which prevents the toxic impact of metal cations such as Al, Ti, Mn, Fe, and Zn, which are considered the main toxic components of underwater welding emissions.

Automated summary

This study evaluated the aquatic toxicity of two suspension samples obtained from underwater welding using electrode and flux-cored wire on marine microalgae Attheya ussuriensis and Porphyridium purpureum. The results showed that the suspension obtained from welding with electrode had an acute toxic impact on A. ussuriensis, while both suspensions had chronic toxicity with a 40% growth rate inhibition in this microalga. However, P. purpureum showed tolerance to both suspensions due to the presence of an exopolysaccharide covering that prevented the toxic impact of metal cations.