Neurobehavioral Effects Of Occupational Exposure Research Articles

Neurobehavioral Effects of Occupational Exposure to Organic Solvents Among Male Printing Workers in Hong Kong

The objective of this study was to investigate the neurobehavioral effects of long-term occupational exposure to low levels of organic solvent among male printing workers in Hong Kong. A total of 115 printing workers exposed to organic solvents were recruited from the printing divisions of 3 printing factories, and 101 workers from the binding divisions of the same factories constituted the comparison group. Active and passive samplings were used to assess the occupational exposures to solvents. The World Health Organization Neurobehavioral Core Test Battery (WHO-NCTB) was applied to assess the neurobehavioral functions. Both active and passive sampling results showed that solvent levels were higher in the printing divisions than the binding divisions. The scores of Digit Symbol and Pursuit Aiming were poorer among workers in the printing divisions (all p values <.05). There were no significant differences found between the 2 divisions for other WHO-NCTB tests. The scores of Digit Symbol and Pursuit Aiming showed exposure-response relationship with various solvent exposure indices. Prolonged occupational exposure to low levels of organic solvents was associated with adverse neurobehavioral effects among male printing workers in Hong Kong.

Neurobehavioral effects of occupational exposure to acrylonitrile in Chinese workers

We examined neurobehavioral outcomes of Chinese workers exposed to acrylonitrile, a potentially neurotoxic substance. We used the WHO-recommended neurobehavioral core test battery to assess the neurobehavioral functions of all study subjects. We compared 81 workers in an acrylonitrile-monomer plant and 94 workers in an acrylic fibers plant with 174 workers with no workplace acrylonitrile exposure. Acrylonitrile workers reported increased tension, depression, anger, fatigue and confusion on the Profile of Mood States. Performances in the Simple Reaction Time, Digit Span, Benton Visual Retention and Pursuit Aiming II were also poorer among exposed workers compared to unexposed workers. Some of these poor performances in tests were also related to exposure duration. Given the findings of our study and the limitations of neurobehavioral workplace testing, we found evidence of neuropsychological impairment induced by exposure to acrylonitrile. Further studies are needed to characterize potential neurotoxicity from chronic and acute exposures to acrylonitrile.

Neurobehavioural effects of occupational exposure to cadmium: a cross sectional epidemiological study

BACKGROUNDA patient with unexplained minor behavioural changes associated with an axonal sensorimotor polyneuropathy had a history of chronic occupational exposure to cadmium (Cd). Although animal studies have shown that Cd...

A Study on the Neuropsychiatric Symptom and Neurobehavioral Effects of Occupational Exposure to Trichloroethylene

A Study on the Neuropsychiatric Symptom and Neurobehavioral Effects of Occupational Exposure to Trichloroethylene

Review : Occupational Lead Exposure

During the last 20 years a number of studies have been carried out to investi gate the neurobehavioural effects of occupational exposure to lead. These studies suggest that subtle effects on intellectual functioning may occur at exposure levels below those currently considered in many countries to be suffi cient to protect workers from harm. This paper critically reviews the evidence from these studies and considers the case for reviewing the position on stan dards for exposure to lead in the workplace.

A Study on the Neurobehavioral Effects of Occupational Exposure to Organic Solvents in Korean Workers

In order to investigate the neurobehavioral effects in workers occupationally exposed to organic solvents in Korea using WHO neurobehavioral core test battery (NCTB), a cross-sectional study of 113 male car painters and printers and 81 controls was conducted. Among the seven tests of the NCTB, only four tests-simple reaction time, Santa Ana dexterity, digit symbol, and Benton visual retention tests-were administered to the subjects because of time limitations. Painters and printers were exposed mainly to toluene, xylenes, and methyl ethyl ketone and often to solvent mixtures. The range of the solvent exposure level was 0.10-2.29 of hygienic effect. Poorer performance of Benton visual retention in the exposed group when compared to the control group was found after controlling confounders. No exposure-dependent effect was found. Further investigation with a matched control group regarding confounding factors is required for conclusive results.

Neurobehavioural effects of occupational exposure to organic solvents among construction painters.

A cross sectional study of 101 construction painters was performed to investigate the relation between exposure to mixed organic solvents and changes in central nervous system function. Solvent exposure was estimated using questionnaire data to derive an exposure index (a measure of intensity of exposure) and to estimate the duration and frequency of exposure. Adverse effects on the central nervous system were assessed by self reported questionnaires and eight tests of a computer administered neurobehavioural evaluation system. Factor analysis of both measures of effect yielded factors both biologically plausible and in agreement with other empirical evidence. A consistent positive association was observed between most measures of exposure and the occurrence of neurotoxic symptoms, notably dizziness, nausea, fatigue, problems with arm strength, and feelings of getting "high" from chemicals at work. Associations with exposure were found with the neurobehavioural evaluation system tests of symbol digit substitution and digit span; however, no consistent pattern of effect on neurobehavioural function was observed. This pattern of the occurrence of neurotoxic symptoms without clear evidence of function deficit is consistent with the type 1 toxic central nervous system disorder as classified by the World Health Organisation.

Neurobehavioural effects of occupational exposure to lead.

A set of neurobehavioural tests selected on the basis of information processing theory was used to study the effect of low level occupational lead exposure on 59 lead workers compared with a matched control group of the same number. Only one of the lead exposed group had a blood lead concentration above the current threshold limit value of 3.81 mumol/l at the time of testing (mean 2.36 mumol/l, range 1.19-3.92 mumol/l) and none had been detected above that level in the previous three years. Nevertheless, most neurobehavioural functions tested showed some impairment in the lead workers. Visual sensory function was affected and, perhaps as a consequence, sustained attention and psychomotor tasks were performed more slowly by the lead exposed group. Cognitive functions were also impaired, with sensory store memory, short term memory, and learning abilities all showing deficits in lead workers. Such cognitive deficits may also be partly due to initial degradation of the visual input. Long term memory performance compared equally with control levels possibly because of development of a compensatory strategy such as rehearsal by the lead exposed subjects. Multiple linear regression analysis relating to lead workers test performance and their lead exposure showed that performance on the sensory store memory test alone was significantly related to exposure. This was probably due to the homogeneity of the lead exposed group with regard to blood lead concentrations and the use of blood lead as a measure of chronic lead exposure.

Clinical Evaluation of Neurobehavioral Effects of Occupational Exposure to Organic Solvents and Lead

With increasing frequency clinicians are called upon to assess the neurobehavioral effects of acute or chronic exposure to a variety of neurotoxic agents found in the workplace and the general environment. These evaluations are particularly difficult in view of the limited understanding of the effects of neurotoxic chemicals on central nervous system (CNS) function and the difficulty in characterizing exposure intensity among people exposed in their communities or in their jobs. As a result of recent epidemiologic studies, summarized elsewhere in this volume (see the article by Landrigan), some information has been acquired regarding the relationship between impaired neurobehavioral function and absorption of neurotoxic agents. Since these studies deal with groups of people, statistical analyses are used to explore the relationship between exposure and effect and to attempt to clarify issues of mechanism, differential vulnerability, and reversibility. Epidemiologic studies are useful not only for setting standards for environmental exposure but also in guiding the evaluation of patients exposed to harmful agents. There are, however, many neurotoxic agents for which there are no reliable epidemiologic data that can be used when evaluating individual patients clinically. Moreover, statistical differences observed in group comparisons between exposed and