Objectives were to: (1) assess toxicity of polychlorinated biphenyls on Eisenia foetida, in terms of survival (LC5O/LD5O), and suppression of coelomocytes to form secretory (SR) and erythrocyte rosettes (ER) with, and to phagocytize rabbit erythrocytes; and (2) compare results with those of Lumbricus terrestris to assess relative sensitivities to PCB. Using 5-d filter paper contact exposure protocol, LC50 and LD50 were 30.4 cg/cm2 and 4450 cg/g dry mass, respectively. Nominal PCB exposure concentrations of 5.0 and 10.0 pg/cm2 resulted in tissue levels of 1389 and 2895 pg/g dry mass causing a significant reduction in SR formation by 18 and 52%, respectively. ER formation and phagocytosis were reduced significantly (52 and 61%) only at the higher tissue concentration. Compared to reported data on lethality and immunomodulation in L. terrestris, E. foetida appears to be more resistant.

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The determination of uranium in samples of the enviroment was considered for liquadeted chemical toxicity of uranium and it is impossible to leave out a potential occurrence in drinking water. The purpose of this diploma thesis was the monitoring of preselected public water supplies in the South Moravia and post action analysis of those samples. That was all on the basis of the requierement of the Regional Hygiene Station. For determination of trace concentrations of uranium in drinking waters the method ICP-MS (Inductively Coupled Plasma with Mass Spectrometry) was chosen. All of the results were then summarized and evaluated. At the end are proposed feasible solutions and precautions for public water supplies operators.

Silver nanoparticles (AgNPs) are known to cause ecotoxic effects, but there are no existing derived ambient water quality criteria (AWQC) for these nanomaterials to protect freshwater aquatic life due to insufficient toxicological data. We exposed Hyalella azteca to silver nitrate, citrate-coated AgNPs (citrate-AgNPs), and polyvinylpyrrolidone-coated AgNPs (PVP-AgNPs) in a 10-day and 28-day water-only static renewal system with clean sand as a substrate for the amphipods and compared their point estimates with the United States Environmental Protection Agency (USEPA) AWQC for silver. We observed that all treatments decreased the survival, growth, and biomass of H. azteca, and the order of toxicity was AgNO > citrate-AgNPs > PVP-AgNPs. The LC50s of AgNO, citrate-AgNPs, and PVP-AgNPs were 3.0, 9.6, and 296.0 µg total Ag L, respectively, for the acute exposure and 2.4, 3.2, and 61.4 µg total Ag L, respectively, for the chronic exposure. Acute and chronic EC20s of citrate-AgNPs ranged from 0.5 to 3.5 µg total Ag L while that of PVP-AgNPs ranged from 31.2 to 175 µg total Ag L for growth and biomass. Both Ag released from AgNPs and the nanoparticles contributed to the observed toxicity. The dissolution and toxicity of AgNPs were influenced by surface coating agents, particle size, and surface charge. Most point estimates for AgNPs were above AWQC for silver (4.1 µg L) and the lowest concentration (0.12 µg/L) at which Ag is expected to cause chronic adverse effects to freshwater aquatic life. Our study demonstrates that the current AWQC for silver, in general, is protective of freshwater aquatic life against AgNPs tested in the present study.