This bioaccumulation study was mainly carried out to detect the accumulation of toxic substances in one cell of algae and thus the possibility of introducing a toxic substance into the food chain. The green alga Desmodesmus subspicatus, which is commonly used in ecotoxicological tests, was chosen as a model organism. These algae are single cell freshwater organisms capable of heavy metals accumulation from water.

Algae cells were exposed to selected toxicants (Cr, Zn and Ni) and, after performing ecotoxicological tests (72 hours), they were captured on a filter, dried, decomposed and analysed by ICPMS/MS. Concentration ranges of the toxicant were chosen to include inhibition of algal growth in the range of 0-90%. The resulting toxicant concentration for this experiment was chosen to be 0.3 mg.L^-1, which corresponds to an inhibition of 50%. Cr, Zn and Ni were selected as elements originating from transport; specifically, Ni is not naturally present in cells.

Because this procedure of analysis is laborious and time-consuming, an alternative technique is Laser-Induced Breakdown Spectroscopy (LIBS) working with a Czerny-Turner spectrometer in a double pulse (DP) 1064-1064nm configuration.

It was found that the LIBS method is suitable for simple semi-quantitative analysis. Some interesting facts about LIBS of cellulose filter carrying algae were revealed: Contaminated algae show a monotonic decrease in line intensity with the number of layers of adhesive tape used to fix the filter to the microscope glass, blank and uncontaminated samples nearly do not. The total emissivity, electron number density, and matrix element lines are less intense on the blank than on the contaminated sample. The behaviour of analyte and matrix lines is more similar if their signal-to-noise ratio is high or have similar excitation energies, which may be important for possible internal standardization. The results obtained by both methods (ICPMS/MS and LIBS) can be compared very well.

The resulting contents of the elements in algal cells were recalculated per one cell. The yielded value represents the amount of the elements adsorbed on the surface of the cells and accumulated directly in the cells, which made it possible to assess the relationship among the sample toxicity, accumulation of pollutants and a change in the content of selected biogenic elements in algal cells.