OBJECTIVES This study was conducted to evaluate association between computerized neurobehavioral performance and blood lead concentration in Korean elementary school students. METHODS The subjects were 1,077 elementary school students of Seoul, Busan, Daegu and Gwangju. Blood lead concentration was measured and computerized neurobehavioral performance tests were performed. RESULTS Blood lead concentration of the subjects was in the range of 0.20 and 7.39 microg/dl. The geometric mean of the subjects' blood lead concentration was 1.41 microg/dl. As blood lead concentration increased, reaction time to the symbol digit tended to increase significantly and linearly. As a result of LOWESS(locally weighted scatterplot smoothing), increasing reaction time to the symbol digit was observed. CONCLUSIONS As blood lead concentration under the CDC (center for disease control and prevention) reference value increased, reaction time to the symbol digit tended to increase. But, as the number of subjects over 3 microg/dl is small, it is difficult to make a definite conclusion. If confounding variables are controlled properly in a follow-up study, we can obtain a more definite conclusion.
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Association of heavy metal complex exposure and neurobehavioral function of children Minkeun Kim, Chulyong Park, Joon Sakong, Shinhee Ye, So young Son, Kiook Baek Annals of Occupational and Environmental Medicine.2023;[Epub] CrossRef
Performance assessment on the Korean Computerized Neurobehavioral Test using a mobile device and a conventional computer: an experimental study Young Seok Byun, Sung Kyu Park, Joon Sakong, Man Joong Jeon Annals of Occupational and Environmental Medicine.2018;[Epub] CrossRef
The association between lead concentration in the blood and neurobehavioral performance of children Dae-Seon Kim, Seungchul Ahn, Seungdo Yu, Eun-Hee Lee Toxicology and Environmental Health Sciences.2012; 4(2): 87. CrossRef
Evaluation of reliability of computerized neurobehavioral tests in Korean children Kyeong-Soo Lee, Man-Joong Jeon, Tae-Yoon Hwang, Chang-Yoon Kim, Joon Sakong NeuroToxicology.2012; 33(5): 1362. CrossRef
OBJECTIVES To evaluate effects of lead on the central nervous system of children by measuring blood lead concentration, computerized neurobehavioral function and intelligence of elementary school students. METHODS The study was conducted with 208 elementary school students living in the vicinity of Pohang Industrial Complex in October and November, 2005. Data on demographic characteristics, living environments and lifestyle habits were collected from subjects. RESULTS Blood lead levels of elementary school students ranged from 0.76-4.97 microg/dl, which is below the 10 microg/dl recommended level of CDC. The blood lead levels were similar with those reported in other domestic and international studies. Neurobehavioral tests revealed that most third grade students reacted slowly and their speed declined in simple reaction time (p<0.05), choice reaction time (p<0.05), symbol digit substitution (p<0.01), finger tapping speed nondominant hand (p<0.05) as blood lead levels increased. Sixth grade students demonstrated significance in test performance, and displayed blood lead levels of 2.00-4.00 microg/dl. Results of intelligence testing showed significantly low performance in IQ (p<0.05), vocabulary ability (p<0.05), reasoning ability (p<0.05), mathematical ability (p<0.05) and perception ability (p<0.05) among third grade students who displayed high levels of blood lead concentration. Sixth grade students showed significantly low performance in vocabulary ability (p<0.05) at high level of blood lead concentration. The difference in mean IQ scores between the group with blood lead level of < or =2.00 microg/dl and the group with blood lead level > or =3.00 microg/ dl was 3.21 in third grade students and 4.28 in sixth grade students. Low academic achievement was observed among third grade students (p<0.05) and six grade students (p<0.05) as the average blood lead level increased. Correlation analysis on the association of blood lead concentration with neurobehavioral tests revealed a positive correlation between blood lead levels and reaction time of choice reaction time and symbol digit substitution in third grade students. A positive correlation was observed between blood lead levels and reaction time of symbol digit substitution and finger tapping speed in sixth grade students. There was a negative correlation between blood lead levels and reasoning ability of third grade students (r=-0.247) and vocabulary ability of six grade students (r=-0.255). CONCLUSION There have been few studies on the effects of blood lead on the central nervous systems of children in Korea. The study supports the findings of earlier studies that blood lead has an impact on children. However, the study did not confirm significant association of blood lead concentration with each neurological and motor test conducted for this study due to a small sample size and relatively low blood lead levels of elementary school students. Further studies using a similar assessment methods would be helpful to evaluate the effects of low blood lead levels on the central nervous systems of children.
Citations
Citations to this article as recorded by
Association of heavy metal complex exposure and neurobehavioral function of children Minkeun Kim, Chulyong Park, Joon Sakong, Shinhee Ye, So young Son, Kiook Baek Annals of Occupational and Environmental Medicine.2023;[Epub] CrossRef
The association between lead concentration in the blood and neurobehavioral performance of children Dae-Seon Kim, Seungchul Ahn, Seungdo Yu, Eun-Hee Lee Toxicology and Environmental Health Sciences.2012; 4(2): 87. CrossRef
Evaluation of reliability of computerized neurobehavioral tests in Korean children Kyeong-Soo Lee, Man-Joong Jeon, Tae-Yoon Hwang, Chang-Yoon Kim, Joon Sakong NeuroToxicology.2012; 33(5): 1362. CrossRef
In this study the relationship between occupational lead exposure and minor hearing impairment was investigated in a cross-sectional design with 50 lead exposed workers from January to April 1994, The data were collected from the interview with the structured questionnaire which included sociodemographic variables and medical histories especially ear disease and occupational histories. Lead exposure indices which were blood lead, urine lead, zinc protoporphyrin in urine, and delta-aminolevulinic acid in urine were analyzed, Also study subjects were examined pure-tone hearing test.
The results were as follows ; 1. There were significant differences in lead indices between lead-exposed workers and non-exposed workers.
2. The duration of lead exposure did not affect the hearing impairment among lead exposed workers.
3. Minor hearing impairment were higher in lead-exposed workers than non-exposed workers, but there were not statisticatly significant.
The result from this study indicated that lead exposed workers should be monitored to prevent hearing impairment and would be needed health education.
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Citations to this article as recorded by
Occupational Hearing Loss in Korea Kyoo Sang Kim Journal of Korean Medical Science.2010; 25(Suppl): S62. CrossRef
This research was conducted to determine the usefulness of reported symptoms for the diagnosis of lead poisoning for workers exposed to lead. A group of 147 male lead smelting workers were given special physical examinations from June to September of 1989. The examinations included the reporting of ailments(symptoms) by the workers, as well as analyses of their blood lead concentrations and urinary coproporphyrine and delta-aminolevulinic acid concentrations. the associations were analyzed between the bilogical exposure indices and the symptoms described by the workers.
The results were as follows: 1. The only symptoms which were described more frequently by the lead workers compared to the control group were paresthesia of the extremities, myalgia, arthralgia, and insomnia. The frequency of other symptoms described were actually lower for the lead-exposed workers.
2. For those workers whose blood lead concentrations were above 60 microgram/dl, only the increase in the frequencies of arthralgia and paresthesia of the xtremities were statistically significant, compared to those workers whose blood lead concentrations were below 60 microgram/dl. Also, arthralgia was the only symptom which increased in frequency in workers whose ruinary coproporphyrine concentrations were above 100 microgram/l; however, this increase was not statistically significant by urinary delta-aminolevulinic acid levels.