Lead exposure and measure of IQ level among children in Alaverdi, Akhtala and Yerevan

Abstract

Background Information: Lead (Pb) pollution is considered to be one of the top ten global environmental pollution problems. Exposure to lead among children, particularly six years old and younger causes lower Intelligence Quotient (IQ), behavioral changes, concentration disorder, mental deterioration after 18 months and leads to loss of motor skills and retarded speech development. Infants and young children are more sensitive to lead exposure because the developing nervous system is much more vulnerable to the effects of lead than the adult's brain. The risk for children’s exposure is also higher because of children’s hand to mouth behavior. Alaverdi is a large industrial city in Armenia with a polymetallic smelter which emits heavy metals to the environment. The concentration of those heavy metals in residential soil exceeds the standard established by the United States (US) Environmental Protection Agency (400 mg/kg). In 2001, in Alaverdi, 34% of soil samples and 77% of loose dust samples exceeded the US Environmental Protection Agency (EPA) standard of 400 mg/kg for bare soil in children’s play areas. In 2001, 36% of floor dust samples from apartments exceeded the US EPA standard of 40 µg /ft2 . Specific Aims: The research questions of the study are: • What is the children’s IQ level in Alaverdi, Akhtala and Yerevan? • Are there differences in IQ’s of children living in Alaverdi, Akhtala and Yerevan? Objectives of the study are: • To determine IQ scores of children 4-6 years old in Alaverdi, Akhtala and Yerevan and check for differences between the places of residence • To determine the association between children’s IQ,BLL and place of residence after adjusting for other risk factors for children’s low IQ Methods/Study Design: To assess and compare IQ scores in children in cities Alaverdi, Akhtala and Yerevan, cross-sectional study will be conducted. Approximately 163 children will participate in the study. The study population will include those children whose blood lead levels were assessed during the fall 2013 as part of the study the American University of Armenia School of Public Health conducted. That study included 39 children randomly selected from Akhtala, 69 from Alaverdi and 55 from Yerevan (Erebouni region) by using information taken from polyclinic registers. Children’s IQ will be determined by using the Wechsler Intelligence Scale for Children, which is designed for children 6-16 years old. Data Entry/Data Analysis: Statistical analysis will be conducted by STATA statistical software; SPSS 17.0 software will be used for double data entry. Descriptive statistics will be used to describe the basic features of the data in the study. Simple and Multiple Linear Regression Models can identify the relationship between variables and control for possible confounding factors. Analysis of Variance (ANOVA) will be used to determine whether a difference exists between the means of three independent groups. Budget: The research team will conduct the study in 2015 and it will last 3 months. The estimated budget for implementation of the proposed study is 2,573,226AMD or 6,230 USD.