Mini Review
Jeni Staykova
Abstract
For more than 55 years is the environmental pollution region of Kardzhali in Bulgaria has been due to intense emissions from mining-processing, smelter plant and processing of nonmetallic minerals. The main source of pollution in those years is smelter plant (Lead and Zinc Complex), but from 2011 to 2012 respectively, lead and zinc production was gradually stopped. One of the mechanisms to assess the health risk among the population is to conduct biological monitoring, to make biological materials to determine the concentration of heavy metals in them. The most vulnerable group is children. The aim of this study is to benchmark the results of the biological monitoring of children aged between 9 to 14 years in the city of Kardzhali for the 1991-2013 periods. Biological monitoring includes determination of lead in the blood of 356 children from two schools in the city of Kardzhali (located near and far away from OCK-AD) and one in Krumovgrad (for control). In accordance with the methodology in Bulgaria (included children), drawing of USA methodology received results in the following: According to the individual results for the period 1991-2002, when smelter plant has worked, in 71% of the children in Kardzhali values of lead in the blood are below 100 μg/l, in 24% between 100 and 200 μg/l and in 5% over 200 μg/l. In 2013, when the company ceased operation in 92% of surveyed children the levels of lead in the blood is below 100 μg/l, in 7% from 100 to 200 μg/l and in 1% above 200 μg/l. The results indicate a link between air pollution with lead aerosols and the level of lead in the blood of children In the intensive work of the plant during 1991-2002 years in 29% of children amounts of lead in the blood is above 100 μg/l. In 2013 (when closed proceedings) only 8% of children are with lead content in the blood of more than 100 μg/l. The blood of the children in the control group demonstrated no lead content at 100% of children.