[Chlorinated pesticide residues and polychlorinated biphenyls in fish from various locations in Czechoslovakia]. / Rezidua chlórovaných pesticidu a polychlórovanych bifenylu v rybách pocházejících z ruzných lokalit CSR.

Samples of 14 fishes (175 samples on the whole) were examined in 1984 to 1986 for residues of chlorinated pesticides and polychlorinated biphenyls. Residues of the given substances were present in all the samples. The contents of chlorinated pesticide residues in fish are influenced mainly by the food spectrum; significant influence was also exerted by the contamination of the environment where the fish lived, by the age of the fish, and by the amount of their body fat in which the lipophile chlorinated carbohydrates are stored. No tolerance limits have been proposed in Czechoslovakia for the residues of chlorinated carbohydrates in fish bodies, except for the sum of DDT = 2.00 mg per kg of fat. When the data on the fish samples were compared with the highest admissible content of chlorinated pesticides per unit mass of fish muscle tissue tolerated in the FRG and the content of PCB tolerated in the USA, the fish from the Vltava river downstream of Prague fail to comply with these FRG and US regulations; all fish from all other places comply with them. Owing to large differences in the contents of fat in muscle between different fishes, it is more conclusive from the point of view of food hygiene to express the results as data per 1 kg of muscular tissue; these data represent real contents in fish as foodstuff.

[Residues of chlorinated pesticides and polychlorinated biphenyls in pork and ham in past years and today]. / Rezidua chlórovaných pesticidu a polychlórovaných bifenylu ve veprovém mase a sunkách v minulých letech a v soucasnosti.

The contents of the residues of chlorinated pesticides and polychlorinated biphenyls (PCB) were investigated in 682 samples of ham and 926 samples of pork that were collected in the export meat plants. The investigation, based on the gas chromatography method with an EC detector, was performed in 1986. The tolerance of the residues of chlorinated pesticides was exceeded in 0.4% of the hams and 0.3% of the pork samples in that year. The PCB limit, proposed for pork (1.0 mg per kg of fat) was exceeded in 0.7% of the hams and 0.8% of pork samples; it can be seen from these data that the residue contents were considerably reduced in comparison with the year 1983 when this limit was exceeded in 7.0% of the hams and 6.2% of the pork samples. This decrease is due to the fact that the production of PCB was stopped, their use has been restricted, and the persons working with preparations containing PCB have been better informed about the chemical persistence, problems of residues and the like. The meat of wild boars is more contaminated than is the meat of the domestic pigs reared in large herds; this applies, first of all, to the residues of the DDT series (12.7% of the meat samples of the wild boars exceeded the limit of 2.0 mg per kg of fat) and also to the residues of HCB, lindane, and PCB. As for the PCB residues, the maximum tolerated residue content was never exceeded. A decrease in the contents of chlorinated pesticide and PCB residues resulting from the limited use of these chemicals is faster in the meat of the domestic pigs than in that of the wild boars.

[Residual chlorinated pesticides and polychlorinated biphenyls in the eggs and adipose tissue of wild birds]. / Rezidua chlórovaných pesticidu a polychlórovaných bifenylu ve vejcích a tukových tkáních volne zijících ptáku.

In 1983 and 1984, in the State Veterinary Institute at Jihlava, 129 samples of eggs of wild birds of 14 species were analyzed coming from different regions of the Czech Socialist Republic for the presence of residues of chlorinated pesticides and polychlorinated biphenyls (PCB). Apart from this, nine samples of hawk fat and 27 samples of buzzard fat were examined. The method of gas chromatography with a detector of electron capture was used for the analysis. The analyzed samples were found to contain residues of PCB, DDT (and mainly its metabolite DDE), HCB, alpha-HCH, gamma-HCH. No residues of other chlorinated carbohydrates were detected. The residue levels of these substances in the eggs and fatty tissues of different species of wild birds vary within a very wide range. A significant influence is exerted on these levels by the differences in food spectrum, the age of the birds, lack of food causing mobilization of food reserves, and mainly the environment where the birds live. The highest levels of residues were found in the eggs and fatty tissues of predatory birds with a narrow spectrum of food, i.e. those feeding on other birds (sparrow-hawk 33.00 mg.kg-1 in the dry matter of eggs, hawk 239.98 mg.kg-1 in fat) or those associated with water (great crested grebe 11.97 mg.kg-1, sea-gull 11.24 mg.kg-1 in the dry matter of eggs). Much lower levels of the residues of the chemicals were recorded in the species feeding mainly on small rodents (kestrel 0.681 mg.kg-1, buzzard 2.456 mg.kg-1 in the dry matter of eggs and 11.398 mg.kg-1 in fat). Some of the samples under study contained dead embryos. These embryos had particularly high residue levels, often higher than the levels regarded in literature as toxic.

Removal of biogenic elements, polychlorinated diphenyls and heavy metals during the biological final treatment of waste-waters.

Algae were cultivated in the effluents from a treatment plant processing communal sewage and waste-water from a large-scale hoggery. The content of nitrogen. phosphorus and also COD and BOD were estimated in the effluent before and after cultivation of algae. It was found that the removal of nitrogen and phosphorus by Chlamydomonas geitleri from the effluent was optimal at highest at the high effluent concentrations while the purification efficiency in relation to PCD content depends on algae used.