Health risk for children from lead and cadmium near a non-ferrous smelter in Bulgaria.

In an interdisciplinary approach the exposure to lead and cadmium of the population living in the vicinity of a Bulgarian non-ferrous metallurgical plant was studied to determine the routes of exposure. Two exposed villages situated 4 and 6 km SW and W, respectively,--in the plume of the plant's emissions--and a village for comparison situated 14 km SE of the plant were selected for the study. The blood of children aged 3-13 years from the exposed villages (n = 111) and the village for comparison (n = 18) was analyzed for lead (PbB) and cadmium (CdB) as well as for free erythrocyte protoporphyrin (FEP) and haematological parameters. A personal questionnaire concerning nutrition habits and life-style was filled in by interviewers of the children's parents. The cadmium levels in blood were within the variation range stated for Bulgaria. The exposed children had a mean CdB of 0.38 +/- 0.18 microgram/l (range 0.10-0.90 microgram/l) and the comparison group 0.31 +/- 0.35 microgram/l (0.06-1.42 micrograms/l). The mean PbB value measured in the exposed children was 240 +/- 96 micrograms/l (77-631 micrograms/l), while the mean value of PbB for the reference group was 149 +/- 57 micrograms/l (63-285 micrograms/l). Individual PbB levels > 150 and > 200 micrograms/l were found in 85% and 62%, respectively, of the exposed children and FEP > 80 micrograms/dl erythrocytes was detected in 21%. There was a concentration-response and a concentration-effect relationship (r = 0.51, D > 0.001) between PbB and FEP. According to the questionnaire only 10.3% of the interviewed families in the two exposed villages buy all food from the market, the others produce a significant part of their food themselves. The PbB levels of children who consume certain foods of local production (cabbage, cereals, poultry, and beef) were significantly higher compared to the PbB values of children whose families purchase these foods from the market. No significant relationship between lead in children's blood and the use of tin and ceramic utensils, drinking and irrigation water, hygiene habits, family tobacco smoking habits, playgrounds and traffic intensity were revealed. There was a significantly higher incidence of prematurely born babies in the exposed population. The proven relationship between lead intake via the food chain and existing significant health risks is the basis for risk communication. Measures aimed at healthier nutrition and life-style intend to contribute to decreasing the risk of the population living in the smelter region.

[Toxicologic evaluation of propyneb on the Wistar rat]. / Evaluation toxicologique du propyneb chez le rat Wistar.

This experiment was performed in Wistar rats of both sexes exposed subchronically to 1:100, 1:500, 1:1000 and 1:1500 LD50. The evaluation was based on endpoints measured on the 30th and 90th after starting exposure and after a recovery period of 30 days: these included clinical signs, functional changes, hematological parameters, urine analysis, biochemical, histochemical, immunomorphological endpoints, electron microscopy of internal organs, chromosome examination of bone marrow. A high lethality was shown to occur with a characteristic clinical picture: interruption of weight gain, behavioural changes, leucopenia mainly involving neutrophil leucocytes, biochemical changes characteristic of liver, cardio-vascular system (myocardium and aorta) together with pathologic, biochemical, histochemical and ultrastructural changes in liver, brain, thyroid gland, myocardium, spleen and bone marrow. Endpoints were shown to be clearly dose-dependently related with small variations with the low dose, i.e. 1:1500 LD50 (5 mg/kg-1 bw).

[Biochemical and histological changes after acute oral poisoning with the acetanilide herbicide acetochlor]. / Modifications biochimiques et histologiques de l'intoxication orale aiguë par l'herbicide acétanilidique "acétochlore".

Changes in the liver of male rats were studied on the 1, 3, 5, 7, 10 and 14 days after a single oral application of 1/5 DL 50 of the chloracetanilic herbicide Acetochlor (DL50 = 1063 mg/kg-1). Two main periods in the action of acetochlor can be identified: between 1-2 days when the influence of the compound itself is predominant and between 5-7 days, when the toxic action of the slowly eliminated metabolites is most pronounced. These two periods provoke a biphasic activation/inhibition response of the liver. Remarkable is the compensatory effect of the cytochrome P-450 system responsible for the metabolism of acetochlor. The phase-specific changes were are followed by pathomorphological observations of liver tissue as well as by the time-course of the biochemical parameters studied in different liver fractions.