Abstract
OBJECTIVES—To examine the effect of lead on postural control of workers who have been exposed to lead. METHODS—63 Male, lead battery workers mean (SD) age 41.0 (7.4) were compared with 48 age matched male controls after excluding those with acute or chronic diseases. Exposed workers had mean (SD) past blood lead concentrations of 37.5 (9.2) µg/dl and 11.2 (5.7) years of employment. Postural control was measured with a computerised postural sway measurement system which measured both sway and total movements. RESULTS—Workers standing straight with eyes open on the bare plates had sway and total movements which were not notably different from controls. On the other hand increased movements were needed in the exposed workers to maintain stability (the general stability quotient 18.2 (5.4) v 15.4 (4.4) in controls, p<0.01) when standing directly on the footplates with closed eyes,, and with the head tilted (15.0 (3.8) v 11.5 (3.0) in controls, p<0.001). Exposed workers also had a trend for less ability to synchronise anterior posterior and lateral sway in the stress positions (0.0625) than had non-exposed workers . Significant but low correlations were found between the estimate of the chronic internal dose of lead and three of 10 of the postural control measurements, and present lead blood concentrations and only one of the 10 measurements and (r values ranged from 0.21 to 0.31, p⩽0.03). CONCLUSIONS—These findings suggest that lead affects postural control in asymptomatic workers. Further studies are warranted to find whether workers with decreased postural control are at increased risk of accidents and the relation, if any, of these measurements with subsequent morbidity. Keywords: postural stability; equilibrium; exposure to lead
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- Araki S., Murata K. Determination of evoked potentials in occupational and environmental medicine: a review. Environ Res. 1993 Oct;63(1):133–147. doi: 10.1006/enrs.1993.1135. [DOI] [PubMed] [Google Scholar]
- Ashby J. A. A neurological and biochemical study of early lead poisoning. Br J Ind Med. 1980 May;37(2):133–140. doi: 10.1136/oem.37.2.133. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Cavalleri A., Minoia C. Lead level of whole blood and plasma in workers exposed to lead stearate. Scand J Work Environ Health. 1987 Jun;13(3):218–220. doi: 10.5271/sjweh.2060. [DOI] [PubMed] [Google Scholar]
- Chia S. E., Chia H. P., Ong C. N., Jeyaratnam J. Cumulative concentrations of blood lead and postural stability. Occup Environ Med. 1996 Apr;53(4):264–268. doi: 10.1136/oem.53.4.264. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Chia S. E., Chua L. H., Ng T. P., Foo S. C., Jeyaratnam J. Postural stability of workers exposed to lead. Occup Environ Med. 1994 Nov;51(11):768–771. doi: 10.1136/oem.51.11.768. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Corsi G., Bartolucci G. B., Fardin P., Negrin P., Manzoni S. Biochemical and electrophysiological study of subjects with a history of past lead exposure. Am J Ind Med. 1984;6(4):281–290. doi: 10.1002/ajim.4700060406. [DOI] [PubMed] [Google Scholar]
- Discalzi G. L., Capellaro F., Bottalo L., Fabbro D., Mocellini A. Auditory brainstem evoked potentials (BAEPs) in lead-exposed workers. Neurotoxicology. 1992 Spring;13(1):207–209. [PubMed] [Google Scholar]
- Fernandez F. J. Micromethod for lead determination in whole blood by atomic absorption, with use of the graphite furnace. Clin Chem. 1975 Apr;21(4):558–561. [PubMed] [Google Scholar]
- Hirata M., Kosaka H. Effects of lead exposure on neurophysiological parameters. Environ Res. 1993 Oct;63(1):60–69. doi: 10.1006/enrs.1993.1127. [DOI] [PubMed] [Google Scholar]
- Jeyaratnam J., Devathasan G., Ong C. N., Phoon W. O., Wong P. K. Neurophysiological studies on workers exposed to lead. Br J Ind Med. 1985 Mar;42(3):173–177. doi: 10.1136/oem.42.3.173. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lille F., Margules S., Fournier E., Dally S., Garnier R. Effects of occupational lead exposure on motor and somatosensory evoked potentials. Neurotoxicology. 1994 Fall;15(3):679–683. [PubMed] [Google Scholar]
- Linz D. H., Barrett E. T., Jr, Pflaumer J. E., Keith R. E. Neuropsychologic and postural sway improvement after Ca(++)-EDTA chelation for mild lead intoxication. J Occup Med. 1992 Jun;34(6):638–641. [PubMed] [Google Scholar]
- Lockitch G. Perspectives on lead toxicity. Clin Biochem. 1993 Oct;26(5):371–381. doi: 10.1016/0009-9120(93)90113-k. [DOI] [PubMed] [Google Scholar]
- Matsumoto T., Fukaya Y., Yoshitomi S., Arafuka M., Kubo N., Ohno Y. Relations between lead exposure and peripheral neuromuscular functions of lead-exposed workers--results of tapping test. Environ Res. 1993 May;61(2):299–307. doi: 10.1006/enrs.1993.1074. [DOI] [PubMed] [Google Scholar]
- Schwartz B. S., Bolla K. I., Stewart W., Ford D. P., Agnew J., Frumkin H. Decrements in neurobehavioral performance associated with mixed exposure to organic and inorganic lead. Am J Epidemiol. 1993 May 1;137(9):1006–1021. doi: 10.1093/oxfordjournals.aje.a116757. [DOI] [PubMed] [Google Scholar]
- Tang H. W., Liang Y. X., Hu X. H., Yang H. G. Alterations of monoamine metabolites and neurobehavioral function in lead-exposed workers. Biomed Environ Sci. 1995 Mar;8(1):23–29. [PubMed] [Google Scholar]
- Yeh J. H., Chang Y. C., Wang J. D. Combined electroneurographic and electromyographic studies in lead workers. Occup Environ Med. 1995 Jun;52(6):415–419. doi: 10.1136/oem.52.6.415. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Yokoyama K., Araki S., Murata K., Morita Y., Katsuno N., Tanigawa T., Mori N., Yokota J., Ito A., Sakata E. Subclinical vestibulo-cerebellar, anterior cerebellar lobe and spinocerebellar effects in lead workers in relation to concurrent and past exposure. Neurotoxicology. 1997;18(2):371–380. [PubMed] [Google Scholar]
- Zhang W., Zhang G. G., He H. Z., Bolt H. M. Early health effects and biological monitoring in persons occupationally exposed to tetraethyl lead. Int Arch Occup Environ Health. 1994;65(6):395–399. doi: 10.1007/BF00383250. [DOI] [PubMed] [Google Scholar]
