Identification and assessment of work-related nervous system lesions.

Short historical data on occupational neurotoxicology, as well as on the pathogenic mechanisms of the nervous system impairments due to occupational factors are described. The main difficulties in the assessment of peripheral and central nervous system lesions are stressed.

[Early neuropsychological dysfunctions in workers exposed to benzene and its homologues].

Psychological examinations using five tests of interference and four tests of motoric reaction were carried out in a group of 28 men occupationally exposed to mixtures of benzene, toluene and xylene compounds. The examinations indicated diminished function of the cortical associative centre, excessive susceptibility to stimuli disturbing psychic processes slowing of the orientation ability and motor reaction time. Tests of habitual interference, reaction time to visual stimuli and Ricossay's test proved to be most useful in the detection of early psychic dysfunctions.

[Medical prevention of chronic occupational intoxications due to metallic mercury].

A group of workers exposed to elemental mercury was monitored over a period of 14 years (1983-1996) at the Institute of Occupational Medicine and Environmental Health, Sosnowiec. Mercury was used as a catalyst in the synthesis of acetic aldehyde and obtaining of chlorine. Every year medical examination was performed in the group of 163-277 persons.

[Prevention of vibration syndrome in selected occupational groups in the metallurgy industry].

Medical examinations were carried out in a group of 297 men exposed to hand-arm vibration in the metallurgical industry. The group consisted of 93 rammers, 77 grinders and 127 chippers. The level of vibration at workposts was also measured.

[Changes in the nervous system due to occupational metallic mercury poisoning].

At the Institute of Occupational Medicine and Environmental Health, during 12 years, chronic mercury intoxication was diagnosed in 34 persons. There were male workers tending technological processes in which Hg was used as a catalyst (synthesis of acetic aldehyde and obtaining chlorine). The length of professional exposure was 13-34 years (mean 20.

[Neurologic aspects of vibration syndrome].

The authors present divergent opinions on the pathogenesis of vibratory syndrome, and primarily on its angio-neurological form, i.e. vascular, neurogenic and immunological theory.

Raynaud's phenomenon in different groups of workers using hand-held vibrating tools.

The dose-effect relationship showed in the Annex A of the ISO standard 5349-1986 can be used for preventing vibration-induced white fingers (VWF) because it allows to calculate the latent period for the lowest risk of VWF. The aim of this study was to assess the risk of VWF in three different occupational groups of workers whose members operated the same vibrating power tools and the same industrial processes throughout the workday. Each occupational group was employed in two foundries and they were considered to be very stable with a low turnover rate.

[Evaluation of health risk in machine operators exposed to whole body vibration].

A total of 45 machine operators employed at the same power station were examined with special emphasis put on the musculoskeletal system. A group of 15 bulldozer operators, 19 engine operators and 11 tractor drives were exposed to the whole-body vibration with average vertical equivalent acceleration ranging from 0.2 mg-2 to 0.

[Examination of health effects after exposure to metallic mercury vapors in workers engaged in production of chlorine and acetic aldehyde. I. Evaluation of general health status].

Physical, neurological and psychological examinations as well as laboratory tests were performed in the group of 147 workers, engaged in the production of chlorine, acetic aldehyde and soda lye, exposed to metallic mercury vapours and in the control group (n = 49). In the evaluation of laboratory tests, morphology of peripheral blood, liver function tests and lipid balance were analysed in the first part of the work. Electroencephalography, electrocardiography and chest X-ray were also performed as auxiliary examinations.

[Assessment of early psychic dysfunctions due to metallic mercury].

The aim of the study was to find the most sensitive psychological test battery, useful for evaluation of the earliest dysfunctions in workers exposed to metallic mercury (Hg). To assess the above mentioned disorders, six tests of interference and four tests of motor reactions were applied. The examinations were performed in 44 male workers exposed to Hg in the process of acetic aldehyde synthesis.

[Aluminum neurotoxicity].

Adverse health effects of aluminium (Al), especially its possible role in aetiology of some human neurodegenerative disorders, e.g. dialysis encephalopathy syndrome, Alzheimer disease, amyotrophic lateral sclerosis of Guam, dementia, are presented.

[Influence of low frequency electromagnetic fields on the nervous system].

The methods present a short review of the literature dealing with non-thermal bioeffect of electromagnetic fields (EMF), mainly of low and extremely low frequency. The main attention is paid to the information about disorders of the nervous system and about epidemiologic studies of brain tumors in the population exposed to EMF. All quoted authors have stressed great difficulties in the right assessment of adverse effects due to EMF's because of their non-specific influence on the biological structures.

Some aspects of health problems due to local vibration.

The development of knowledge of vibration disease during the last century is given. Pathogenetic mechanisms, diagnostic methods, clinical classification, clinical picture and its stadia and diagnostic difficulties are presented here. Measures for its medical treatment and prevention are also described.

[Evaluation of mental functions in workers exposed to metallic mercury, inorganic lead and carbon disulfide].

The aim of the study was to determine the similarities and differences between the groups of dysfunctions detectable using psychologic tests in workers exposed to metallic mercury, inorganic lead and carbon disulfide. The study groups included male workers examined in the Clinic of Occupational Diseases of the Institute of Occupational Medicine in Lodz. The subjects were supposed to the chronically intoxicated with Hg (27 persons), Pb (40 persons) and CS2 (40 persons).

[Local-action vibration and mechanical stress--their hygienic characteristics and medical evaluation of exposed workers].

Medical examination and assessment of the hand-transmitted vibration and mechanical shocks were performed in 69 workers using chipping hammers, grinding tools, pneumatic hammers and forge hammers. Out of the 15 chippers examined, 5 presented vibration-induced white finger syndrome. The latency period for the syndrome was found to be similar to that predicted in the ISO guidelines no.

[Value of the studies of multimodal evoked potentials for evaluation of neurotoxic effects of combined exposure to lead, copper and zinc].

Central nervous system dysfunction was studied in workers with occupational exposure to Pb+Cu+Zn by measuring somatosensory evoked potentials of short and long latency, visual evoked potentials and brain-stem evoked auditory potentials. The tests were done in 40 workers with a history of exposure from 6 to 19 (mean 14.3) years in a copper foundry.

[Value of multimodal evoked potentials in the assessment of the neurotoxic effects of carbon disulphide].

Central nervous system dysfunction among CS2-exposed workers was studied by measuring short latency SSEPs and VEPs. The examinations were done in 40 men. Chronic CS2 intoxication was diagnosed in 21 of them.

Visually evoked potentials and simple reaction times to visual stimuli in chronic disulphide intoxication.

The relationship between parameters of visually evoked potentials (VEPs) and the results of a psychological test assessing the speed of motor reaction to visual stimuli was examined in 21 patients with chronic carbon disulphide intoxication. Correlations obtained suggest cerebral disfunction of the visual pathway and diminished ability to transform visual information to motor reaction at the level of the cortical association centre.

[Value of electroencephalographic examination in the diagnosis of chronic carbon dioxide poisoning].

The aim of this study was to assess the value of EEG examination for the diagnosis of chronic CS2 intoxication in individual cases. 100 electroencephalograms obtained from a sample of 100 workers suspected of CS2 intoxication, treated in clinical department were analysed. The mean age of the group was 51, the mean duration of exposure was 24 years.

Multimodality evoked potentials in occupational exposure to metallic mercury vapour.

Central nervous system dysfunction among workers exposed to metallic mercury was studied by measuring somatosensory evoked potentials (SSEPs) and visual evoked potentials (VEPs). The examinations were conducted in 28 workers suspected of chronic mercury intoxication. They were exposed to Hg for a period ranging from 4-34 years (mean 22.

[Visual evoked potentials and the time of motor reaction to visual stimuli in chronic metallic mercury poisoning].

In a group of 10 patients with diagnosed occupational chronic poisoning with metallic mercury a correlation was sought between the parameters of the visual evoked potentials and the results of the psychological test evaluating the rapidity of motor response to the visual stimuli. The analysis suggest a cerebral dysfunction of the visual neurons and reduced rate of visual information transformation to the motor effector at the level of the cortical association centre.

[Value of electroencephalographic studies for the evaluation of the neurotoxic effect of metallic mercury].

The results of 373 EEG investigations were analysed. They were obtained in a period of 4 years in 222 workers with occupational exposure to metallic mercury in the synthesis of acetaldehyde and salt electrolysis. Abnormal or borderline abnormal results were found in 13% of them.

[Late sequelae of recurrent occupational lead poisoning--the status of the nervous system].

In 44 men with a history of repeated occupational lead poisoning multidisciplinary clinical and laboratory investigations were carried out. The number of lead poisoning episodes was from 2 to 7. Apart from peripheral hypalgesia on the extremities (in 6 cases) no other neurological abnormalities were found.