Biological environmental specimen banking in Slovakia.

Biological environmental specimens, including samples of human tissues, were stored for 5-10 years after solubilizing by mineralization in boiling nitric acid. The sampling procedure, transport treatment and storing was standardized. Documentation identifying the sample and its origin were used. Data on toxic metals in dust-fall, in the individual components of the environment as soil, air, ground and surface water, plants, animals, food and human tissues (liver, kidney, lung, brain, heart and plasma) are reported for the 6 most heavily contaminated regions of Slovakia. In some areas xenobiotics in the environment seriously affected the flora and fauna, including man. Banking of specimens has been stressed as the necessity for future analyses.

Health and chemical environment in Czecho-Slovakia, international cooperation context.

This review provides a record of the present situation with regard to public health and environmental degradation and its underlying causes in Czecho-Slovakia, taking into account "ways of life," which is a synonym for its two components: environment and behavior. It gives attention to the priorities which include air and water pollution and food contamination. "Environmental protection" includes the human health protection from air, water, land, and groundwater pollution, ecological protection and natural resource preservation, use of pesticides, food and consumer product safety, and safety associated with the introduction of new chemicals into commerce. Further, this review focuses on the fundamental building blocks for a new environmental policy and management system (Constitution Act, 1991; Environmental Law, 1991; Chemical Act, in preparation; standards regarding chemicals, etc.). With regard to the international concern about the dangers of chemicals for humanity and the natural environment, attention is drawn to the collaboration of Czecho-Slovakia in chemical safety with WHO, IRPTC, and OECD. An important task is to determine what scientific research is needed and to educate administrators, politicians, and the general public in chemical safety.

Blood and placental concentrations of cadmium, lead, and mercury in mothers and their newborns.

Placental transfer of cadmium, lead and mercury was studied under the conditions of environmental exposures of pregnant women to these heavy metals. Fifty pregnant women from industrial area and a similar control group from a semirural area were examined. Cadmium, lead and total mercury levels were determined in maternal erythrocytes and plasma, in placenta, and in erythrocytes and plasma of umbilical cord blood using atomic absorption spectrophotometry. Except for the cadmium plasma concentration in the control area, levels of the three metals were higher in maternal than in cord blood. The mean plasma values (arithmetic mean) of cadmium, lead, and mercury in industrial area were 0.53, 6.37, and 0.37 micrograms.100 ml-1 in maternal blood and 0.30, 4.82, and 0.31 micrograms.100 ml-1 in cord blood. Highest values of the correlation coefficients were found between the cadmium and mercury concentrations in maternal and cord blood erythrocytes. No striking effect of the place of residence of pregnant women on the heavy metal concentrations in biological materials could be found.

Pesticides.

The last 30 years have been marked by concern regarding the effects of pesticides on human health and on the environment. Unwanted and adverse effects on man and other nontarget organisms have been reported from many countries. The health effects recorded for thousands of people yearly are mainly caused by the inappropriate handling of pesticides or by accidents. The important task is to identify and evaluate the specific hazards of the handling and application of pesticides and the need to collaborate with the World Health Organization (WHO) and other organizations on promoting the health protection of exposed workers. The selectivity of chemical control methods can often be markedly improved by the proper choice of formulation and application techniques and, of course, by an appropriate choice and use of the pesticide itself. This work is an integral part of the international program on chemical safety based on and incorporating current WHO activities. The situation in the developing countries creates a new dimension for the work to be done. In these countries the working populations are affected by the general diseases prevailing in the community, as well as by many uncontrolled hazardous agents at work.

To the question of maximal permissible load with chemical substances in man.

The authors introduce an over-all evaluation of a maximum admissible drug load in man, as related to professional exposure, environmental atmosphere, water, soil, and foodstuffs. To minimize the occurrence of lesions, it is necessary to disclose and classify the environmental factors responsible for homeostasis of the human organism. Moreover, it is desirable to establish the limits of biologically adverse changes of the medium. A real adaptation is possible provided the above changes are sufficiently slow and enable development of optimum mechanisms of reactions within the biological homeostasis. The establishment of an effective system for optimalization of man's environment necessitates further advancement and improvement of methods and their more adequate selection. This adequacy should respond to the real conditions of evaluation of relationships of man and populations with dynamically changing environment. The understanding of general regularities and mechanisms of this complex action will be indispensable. The to-date experience implies that the criteria for determination of the maximum permissible load of environment and man with chemical compounds are quantitative relationships between intensity, frequency and duration of exposure to chemicals in the atmosphere, and the magnitude of undesirable changes in man and his environment. The classification of acceptable or permissible limits of concentration (or other index of exposure) of chemical substances in the atmosphere pursues the protection of the population from undesirable effects under variable conditions of exposure (chemical compounds in working places, atmosphere, alien foreign substances in food, water or soil). The number of potentially toxic substances to be evaluated both hygienically and toxicologically, amounts to about 25 000. Newly introduced chemical compounds annually make about 1000-5000, of which approximately 10% need a thorough examination. The limits can be divided into several groups: Maximum permissible concentrations of chemical compounds (MAC) in working and external atmosphere, water, and partially in soil and food. For these a denomination "derived working limits". Limits of chemical compounds based on their intake by the human organism are sometimes called "primary protection standard". These may correlate with the acceptable daily intake of foreign substances (additives and contaminating substances). The longest tradition enjoys the classification of food additives, which has been supervised since 1956 by the Joint Committee of FAO experts and WHO experts for pesticide residues (1).(ABSTRACT TRUNCATED AT 400 WORDS)

Prophylactic use of restricted antibacterials in Czechoslovakia.

The prophylactic use of restricted antibacterials in Czechoslovakia was studied. Data from 10 hospitals were collected for approximately 10,000 therapeutic applications of eight restricted antibacterials to 8411 patients. The drugs monitored were oxacillin, kanamycin, gentamicin, carbenicillin, co-trimoxazole, colistin, cephalosporins, and lincomycin/clindamycin. Within one year in the 10 hospitals studied, 943 of 8411 patients (11.2%) received one of the restricted antibacterials for prophylaxis. In the newborn ward, 61.7% of all restricted antibacterial therapy was for prophylaxis; in the gynecology and obstetrics ward, 32.2%. Approximately 14% of patients receiving restricted antibacterials for prophylaxis received two or more, and many of them received nonrestricted antibacterials concurrently. Duration of therapy with these drugs averaged 7.9 days, and 10% of these courses of therapy exceeded 11 days. Although the selection of individual restricted antibacterials for prophylaxis was generally satisfactory, irrational prolongation of therapy was not, indicating that use of these drugs must be supervised carefully.

Prevention of health damage caused by agrochemical substances.

Present paper refers to prevention of health damage caused by agrochemical substances in Czechoslovakia. Authors introduce criteria for the approval of agrochemicals in agriculture [altogether a list of 526 pesticides in 1981]. In socialist countries uniform maximum permissible levels of pesticides in foodstuffs and uniform analytical methods are being established. The necessity of epidemiological studies and that of monitoring pesticide residues in the environment are stressed. During 1973-78 altogether 80 cases of occupational poisoning by pesticides were notified in Slovakia; out of them 45 being severe and 3 lethal ones. Emphasis is given to the need of systematic checking of the use of pesticides in agriculture from the health prevention point of view.

Chemization and human health.

A survey of the relationships between chemization and human health is presented From among approximately 50 000 chemicals being used, some 5 to 10% represent potential hazards. Classifications and transformations of chemicals in abiotic and biotic conditions, characteristics of their effects according to toxicological and ecological-toxicological criteria (physical-chemical and chemical properties, levels, necessary for the induction of biological and adverse effects, conditions of the exposure of humans and ecological systems) are being dealt with. Attention is devoted to the International Programme on Chemical Safety from the aspects of coping with chemical hazards on a global scale. The criteria of "non-safety" and "safety" of chemicals, prognostics of chemical hazards and the needs of further knowledge (quantity and "fate" of chemicals in the environment, their effects on man and ecological systems and their interaction) are discussed. In the conclusion, the need of international unification of criteria for introducing new chemicals, being of great importance not only from the aspect of the population's health protection--but also from that of facilitating foreign trade in chemical products, is stressed.

[Ecotoxicological study of chlorinated pesticides]. / Okotoxikologische Studien über chlorierte Pestizide.

The authors describe a model for the ecotoxicological investigation of pesticide residues guided by the analysis of various links of the food chain and of human materials. It is pointed to the possibility of studying the dynamics of the exposure to human beings by analyzing gynaecological material (prenatal stage) and samples obtained at necropsy from human beings of varying age (different durations of exposure). The observations of the relative accumulation of hexachlorobenzene, beta-BHC and DDT in butter, human milk and human fat in a region with intensive cultivation revealed a considerble accumulation of hexachlorobenzene which reaches the level of DDT. The conclusion drawn from ecotoxicological studies indicates that a reduction of the tolerances of pesticide residues in raw materials for baby foods is imperative. The analyses of gynaecological material (202 samples of the available content of the uterus and 24 placental and embryonic specimens) permitted to evidence a significant difference between two regions and a specific relationship of the observed substances and their metabolites to the fat-dissolving power of the analyzed materials.