Health-ecological Investigation of Soil Pollution with Heavy Metals and Arsenic in a Metallurgical and ore output region

The investigation is executed in a central Bulgarian region with both well developed agricultural and metallurgical activities. The agricultural land is approximately 38,700 decares. Geographically the region is estimated as closed valley with dominating winds into south-west and south-east direction. The survey of the heavy metal soil pollution is executed in the south-west part of the valley, characterized with high density of ore-dressing factories and landfills for industrial hazardous wastes. Executed is collection of soil samples and analysis of probes from 4,500 decares including agricultural land and three living areas, two of the last situated 1,000 m to the north-east (Chavdar village) and south (Benkovski village) from the landfill for industrial wastes. Determined are the following average concentrations for heavy metals: lead – 110 mg/kg soil; copper – 280 mg/kg; zinc – 130 mg/kg; cadmium – 0.75 mg/kg; arsenic – 18 mg/kg. Studied are also the heavy metals content in plants. The soil and plant pollution in the region is realized mainly through the aerosol pathway. Proved is the existence of possibilities for dispersion of dust particles, coming from the landfill for industrial wastes. Analyzing the morbidity rate for the region for groups of the population (children and adults), found are respiratory and allergic disturbances to be with higher frequency rate compared with the average data for the country. The general conclusion of the achieved results proves that the pollution of the soils comes primarily from the found 12 km in east direction non-ferrous ore-dressing and metallurgical plant. The correlation between the soil pollution and the morbidity of the population allows the creation of prophylactic programs including change in the land used for agricultural purposes, sowing only definite plant cultures and some other measures aiming at limitation of the health risk.