The use of living organisms to provide information on the quality of aquatic environments is now a widely accepted methodology for assessing contaminant bioavailability. Molluscs have developed tolerance mechanisms towards environmental stressors and can accumulate a large range of contaminants. The assessment of marine environment quality was based on heavy metals (HM), persistent organic pollutants (organochlorine pesticides – OCPs and polychlorinated biphenyls - PCBs) and polynuclear aromatic hydrocarbons (PAHs) analysis in Mytilus galloprovincialis, Rapana venosa, Anadara kagoshimensis species sampled during 2016 - 2020 along Romanian Black Sea coast. Toxic metals (cadmium, lead) had bioaccumulation levels below threshold values in most molluscs samples investigated. Cadmium registered few values (15%) surpassing maximum admissible levels, in all three species. Data evaluation demonstrated the maintenance of a high level of concentrations of persistent organic pollutants in the mollusc tissue, but also of the exceedances of the values that characterize the good ecological status of these compounds. Polynuclear aromatic hydrocarbons showed a declining trend and no exceeding of the maximum allowed limit for benzo[a]pyrene was recorded in the last years. In consequence, the overview assessment based on “OneOutAllOut” (OOAO) approach, considering all groups of substances, indicates a bad chemical status for this period.

"Macroalgal cultures, a new domain for the Romanian Black Sea coast, provide interesting information on the intermediate stages of development and reproduction of algae, and also raw algal material with exploitable potential in most of diverse fields (industrial, cosmetic, pharmaceutical). Porphyra and Pyropia species are considered the world most valuable mariculture algal products. The aim of the paper was to present the comparative aspects regarding the chemical composition (heavy metals, lipids and organic contaminants, respectively, polycyclic aromatic hydrocarbons, organochlorine pesticides and polychlorinated biphenyls) of the specimens obtained in laboratory culture with those collected from the natural environment. The analyzed biological material consisted of P. leucosticta tissue harvested from both laboratory culture and natural environment. After 5 months of experimental culture, the obtained wet biomass was 44.23 g, while the lyophilization dried biomass was 4.94 g. In the specimens obtained through reproductive elements manipulation, under laboratory-controlled conditions, 7 organic compounds were detected, which represent a much smaller number compared with the 20 compounds detected in specimens collected from natural environment. Meanwhile, the presence of all chlorinated organic pollutants was identified in the algal material collected from natural environment. Also, the lipids content was higher in cultured organisms. Heavy metal concentrations (20.72 - 31.91 µg/g d.w. Cu; 0.01-0.21 µg/g d.w. Cd; 12.14-18.69 µg/g d.w. Ni; 0.01-9.56 µg/g d.w. Cr) were comparable with the ranges reported for various macroalgae species from Black Sea region. Key-Words: macroalgae culture, chemical composition, organic contaminants, heavy metals "