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PubMedDate not supplied

Infrared radiation exposure in traditional glass factories.

This article reports on a general method of evaluating exposure to infrared radiation (IR-A, IR-B, IR-C) from high temperature (T > 1000 degrees C) black body sources, simply by performing measurements with a luxometric and/or near IR detector. The method, which may be applied to any black body source, uses the universality of the Planck formula for the black body spectrum, which allows estimation of the radiated power in any wavelength range by measuring the power radiated in another range. This capability may be very useful when the range of interest is one in which radiometers are expensive and difficult to calibrate, as for the IR-B and IR-C ranges, because a more commonly available luxometer can be used instead. The results of measurements and evaluations in two traditional Italian glass factories are reported and compared with the threshold limit value given by the American Conference of Governmental Industrial Hygienists. Intense exposures in the IR-B and IR-C ranges has been found for some workers, exceeding the limit by a large factor. This exposure must be reduced, as it has been shown by epidemiologic studies that there is indeed a correlation between cataractogenesis and work with fused glass and metals.

Cataract↗
PubMedDate not supplied

[Proposals on health surveillance contained in the bill No. 2389 presented by Senator Smuraglia].

The Italian Interassociative Council for the Prevention has examined the bill n. 2389 of senator Smuraglia, expressing appreciation for the initiative (demanded since a long time by the operators of the field) and for the remarkable commitment in the drawing up of such an extensive and well-organized text. At the same time the IICP set up and forwarded to senator Smuraglia some notes and additional proposals, as well as proposals for partial changes, on the following topics:--employer's functions--relationship between the employer and the surveillance bodyprevention and protection service--medical surveillance and "Competent Doctor" threshold limit values--informational system--institutional expertise--omologation--penalty system. In this report we quote the notes expressed with reference to the chapter about the medical surveillance and the competent doctor, of interest of this meeting. We can anticipate with satisfaction that senator Smuraglia admitted many of our proposals and that on their basis he signed a few amendments. Between the proposals we suggested I would like to mention the one concerning the overcoming of the existing medical surveillance system. This is a strict system, essentially outlined by the Law 303/56 (article n. 33) and by the Law 1124/65, by now inadequate with reference to the new working reality and to the current pathology correlated to it. We submit some considerations and the first hypothesis on the constructions of a model of medical surveillance more flexible and open, in conformity with the new reality and the recommendations of the E.U.

Clinical Competence↗
PubMed2000

Regression method to estimate provisional TLV/WEEL-equivalents for non-carcinogens.

There is a huge and changing number of chemicals in commerce for which workplace exposure criteria have not been assigned. Assigning an exposure criterion by an expert committee is resource-intensive-not soon available for the large majority of chemicals in current use. In the absence of assigned criteria, we have provided a regression method to estimate a first-screen estimate of a 'TLV/WEEL-equivalent' inhalation time-weighted average exposure criterion for a pure chemical (or chemical group) from a measure of a non-stochastic toxic exposure to elicit a chronic or sub-chronic health effect, known as a lowest observable adverse effect level (LOAEL) or a (highest) no observable adverse effect level (NOAEL). Results are presented for six data sets for which both a threshold limit value (TLV) or workplace environmental exposure level (WEEL) exposure criterion is presently assigned, and a LOAEL or NOAEL measure of toxic health effect was available from the United States Environmental Protection Agency Integrated Risk Information System data base. The results can be applied as a first estimate of exposure to substances for which no TLV or WEEL (TLV/WEEL) exists, and also serve as a mechanism for identifying substances for potential re-evaluation of their exposure limit, based on their relative position about the prediction models.

Air Pollutants, Occupational↗
PubMed2001

On the validity of classifying chemicals for persistence, bioaccumulation, toxicity, and potential for long-range transport.

It is argued that chemical substances can be meaningfully ranked or classified according to their persistence (P), bioaccumulation (B), toxicity (T), and potential for long-range transport (LRT) only if these attributes can be shown to be intensive, as distinct from extensive, properties of the substance, i.e., they are independent of quantity of substance. It is shown that P, B, and LRT can be considered intensive or quasi-intensive properties, but toxicity is more problematic. To obtain an intensive metric of toxicity requires selection of one of several possible extensive quantities that define exposure or dose. Ranking of a group of chemicals by toxicity is shown to be very dependent on which quantity is selected. It is suggested that toxicity metrics, such as lethal concentration to 50% of the population (LC50), lethal dose to 50% of the population (LD50), and threshold limit value (TLV) suffer the severe disadvantage of being dependent on the efficiency of delivery of the substance to the site(s) of toxic action in the organism. The use of measured or calculated internal dose is a preferable measure of toxicity since it reduces ambiguities inherent in the other metrics. Also, the primary concern is not the quasi-intensive property of toxicity; rather, it is the risk of toxic effects, an extensive quantity. To adequately assess the risk of toxic effects, both the toxic hazard and the degree of exposure must be characterized. Since exposure cannot be estimated without knowledge of the emission rate of chemicals to the environment, a compelling case can be made that screening to identify priority P, B, T, and LRT substances should be expanded to include quantity released to the environment as an additional factor.

Animals↗
PubMedDate not supplied

[Application of transcranial magnetic stimulation for monitoring of the motor cortex condition in dynamics in healthy subjects].

Transcranial magnetic stimulation (TMS) is used already for sixteen years for studying human central nervous system. The main objective of this work was to study motor thresholds and their hemispheric asymmetry in healthy subjects during TMS. We examined 31 righthanded healthy students. Their motor thresholds were measured in May (before vacations), September (immediately after vacations), and November (two months after vacations). Magnetic stimulator Neurosoft-MS (Ivanovo, Russia) was used for TNS of the motor cortex. It was shown that in the absence of regular active functional loads on the right hand, the motor thresholds in healthy righthanders significantly increased under the TMS of the left hemisphere, and hemispheric asymmetry disappeared under conditions both of muscle relaxation and voluntary contraction. Motor thresholds under the left-side TMS decreased and hemispheric asymmetry recovered with the restart of the regular active functional loads on the right hand.

Adult↗
PubMed1976

Prevention of bony fluorosis in aluminum smelter workers. Absorption and excretion of fluoride immediately after exposure -- Pt. 1.

1. A program for the prevention of excessive fluoride absorption among aluminum smelter workers is described. This surveillance is based upon knowledge of the portals of entry, distribution, bone deposition and excretory patterns of this element. 2. The control program is based on the thesis that the concentration of fluoride in the urine two to three days after cessation of work-related exposure reflects the bony burden of this element among this occupational group. Further, this program assumes that the concentration of urinary fluoride after three to five days of shift work reflects the extent of work exposure, adequacy of hygienic and engineering controls and work practices. The limitations of such program as it applies to individual samplings of workers is emphasized. 3. A balance between inhaled fluoride and urinary excretion over a 24-hour period (beginning with work exposure) is attempted. An approximate model for aluminum smelter workers in a near equilibrium F balance is constructed. The role of particle size distribution as a determinant of body loading is emphasized. Because of considerable variation in uptake possible with differing particle size distributions, the actual body F loading potential is inadequately determined on the basis of F concentrations in air. These data also suggest that gaseous fluoride is probably adsorbed upon particulates and absorbed at the alveolar level in the same fashion as respirable particulate fluoride. 4. The regression of ambient fluoride on urinary excretion suggests that the present threshold limit value for fluoride might be more appropriately set at 2 mg/M33 for an eight-hour day.

Air Pollutants, Occupational↗
PubMed2002

[Organizational stress and noise exposure in workers at the packing plant of a brewer factory].

The purpose of this study was to identify and to evaluate the psychosocial factors that produce organizational stress in workers at the packing plant of a brewering industry, and to determine the influence of industrial noise in the occurrence of stress at work. The Questionnaire of Organizational Stress of the ILO/WHO was applied to 163 workers to evaluate psychosocial factors at work, and the socio-demographic characteristics were explored on an individual basis. The equivalent continuous sound level (Leq) was determined and the octave band were determined with a sonometer according to the COVENIN guidelines. Total stress was found in 55 workers (33.74%). Of those, 42 workers were in an intermediate level (25.76%) and 13 workers (7.98%) were in the stress level (p < 0.0001). The occurrence of pondered stress was 100%, classified as: influences of the leader (14.00 +/- 7.27; 87.7%), organizational structures (12.36 +/- 5.14; 93.3%) and organizational climate (11.83 +/- 5.09; 95.1%). The mean of total and pondered stress showed an upward tendency as age and labor antiquity increased (p < 0.05). Leq was in a range of 87.9-100 dB(A), which exceeds the threshold value limit. There was no association between Leq was stress. The level of total stress that these workers perceive is similar to that described in other studies. The pondered stress becomes a highly sensitive variable to determine which psychosocial factors produce stress. This can be used for implementing control and preventive measures of organizational stress.

Adult↗
PubMed2002

Effects of Occupational Exposure to Mercury or Chlorinated Hydrocarbons on the Auditory Pathway.

The purpose of this study was to examine the effects of industrial exposure to mercury and chlorinated hydrocarbons (CH) on the auditory pathway. To this effect, auditory brainstem responses (ABR) were recorded from 40 workers exposed to mercury, 37 workers exposed to CH and from a control group of 36 subjects that were never exposed to neurotoxic substances. The interpeak latency (IPL) of waves I-III, III-V and I-V were measured. The mean duration of exposure to mercury and CH was 15.5 (+6.4) and 15.8 (+7.2) years respectively. The air sample monitoring of mercury was 0.008 mg/m(3) (0.32 of the Threshold Limit Value - TLV(R) as published by ACGIH 2000). The mean average air sample monitoring was found to be 98 ppm for TCE, 12.7 ppm for PCE and 14.4 ppm for TCA which is respectively between 0.28 - 0.51 of the TLV(R) of CH. The mean blood mercury (B-Hg) levels were found to be 0.5mgr% (+0.3mgr%), which is 0.13 of the upper range of the permitted biologic exposure index (BEI) published by the ACGIH 2000. The mean urine samples levels of trichloroacetic acid were between 0.11-0.2 of the permitted BEI for the CH workers. The percent of workers exposed to mercury and CH workers with abnormal prolongation of IPL I-III was higher than the control group (42.5% and 33.8% vs. 18.0% respectively p<0.02). These results are consistent with other studies and show that ABR may provide a sensitive tool for detecting subclinical central neurotoxicity caused by CH and mercury

Journal Article↗
PubMed1992

[Lead and health].

Large sums are being invested in the USA at present with a view to reducing the exposure of risk groups to lead. The Centers for Disease Control (Atlanta) have recently issued new limits for lead concentrations in children, the Occupational Safety and Health Administration is preparing to issue new threshold limit values (TLVs) for airborne lead in the USA, and a national laboratory control system is being built up.

Adult↗
PubMed2004

Health implication among occupational exposed workers in a chromium alloy factory, Thailand.

This study was conducted to assess the occupational exposure and its health impact on the chromium alloy workers. Environmental and biological monitoring, noise and audiometry measurements were done to evaluate the exposure levels in the factory. A total of 112 non-smoking workers were monitored from July 2001 to August 2002. The results showed that most of the chromium and lead exposures in the factory were below the ACGIH-TWA of 50 microg/m3 for chromium(VI) and OSHA-PEL of 50 microg/m3 for lead. The highest chromium (7.25 +/- 0.16 microg/m3) and lead (14.50 +/- 0.29 microg/m3) concentrations were measured in the vibro room. The results indicated that elevated concentrations of chromium and lead were found in both blood and urine samples especially in those areas which were characterized by poor ventilation. The metal contents in blood and urine samples were significantly correlated with airborne metal concentrations in the factory. The result demonstrated that blood and urinary levels among workers were associated with increasing age and duration of exposure. The background noise level of the factory ranged from 67.6 to 89.2 dBA and was frequently higher than the threshold limit value for noise (90 dBA). According to the audiometric test, the exposed workers showed signs of noise-induced hearing loss. Noise at work continued to be an important factor to hearing loss among exposed workers. In our statistical analysis, a significant hearing loss was established on age effect and year of exposure among the workforce.

Age Factors↗
PubMedDate not supplied

[Cardiopathy caused by physical or chemical agents].

BACKGROUND: Occupational cardiovascular diseases do not possess any specific clinical and physiopathogenetic features. OBJECTIVES: The paper summarizes the results of the most recent studies on chemical and physical cardiovascular risks, and assesses the current degree of risk for occupational cardiovascular disease. METHODS: Scientific literature and medline databases on this topic were carefully considered. RESULTS AND CONCLUSION: The scientific literature often provides interesting information on the cardiotoxicity of chemical and physical agents in workplaces; however, a large amount of data refers to high-dose exposures. On the contrary, nowadays exposure conditions have progressively improved and toxic concentrations in air in most cases are below the environmental threshold limit values. In workplaces multiple exposures to different cardiovascular risks, both occupational and non-occupational, are often present simultaneously and these cardiovascular diseases have not been adequately studied in comparison to other occupational organic and systemic diseases. Moreover, possible interferences between occupational cardiotoxic substances and cardiological therapy are still poorly investigated, even though such situations frequently occur.

Air Pollutants, Occupational↗
PubMed2004

[A group carbon monoxide poisoning].

The aim of the study was to present the group carbon monoxide poisoning in Kraków in December 2003. Despite the reanimation procedure one fatal case was stated on the spot (HbCO--60% according to post-mortem toxicological examination). CO threshold limit values were significantly exceeded in the whole building. The inhabitants (15 persons) were transported to the Department of Clinical Toxicology Jagiellonian University Medical College. Also 4 staff members of the ambulance and 2 policemen called to the incident, were diagnosed and observed. Totally, toxicology medical care was given to 21 CO exposed persons. In 8 of them acute CO poisoning of minor grade was stated. Any clinical symptoms of poisoning in the rest of CO exposed persons were noted.

Adolescent↗
PubMedDate not supplied

[Neurobehavioral tests in occupational medicine: diagnosis and prevention].

Modern neurobehavioral methods are used in the assessment of the early effects due to exposure to neurotoxic agents in working and general environment. This paper describes the history and evolution of neurobehavioral methods and their contribution for research on the effects due to the exposure to neurotoxic substances. Moreover, the paper describes the different fields of application of neurobehavioral tests: experimental, epidemiological and follow-up studies, health surveillance, clinical diagnosis, definition of job fitness and risk assessment for the definition of threshold limit values.

Air Pollutants, Occupational↗
PubMedDate not supplied

[Carpal tunnel syndrome among supermarket cashiers].

We studied Carpal Tunnel Syndrome prevalence in part time and full time female supermarket cashiers and in a control group (female primary school teachers). Subjects underwent a clinical examination in which information about personal, physiological, pathological and occupational factors were collected by a physician with a questionnaire and a self-administered Katz's hand diagram. The study protocol included median nerve conduction studies (NCS) for each worker, performed bilaterally according to the palmar technique described by J. Kimura. Case definition of Carpal Tunnel Syndrome was based on the combination of typical symptoms (classic/probable or possible) and electrodiagnostic findings according to the Consensus Criteria for the Classification of Carpal Tunnel Syndrome published by Rempel et al. in 1998. Biomechanical risk for upper limb was assessed by a group of trained observer using videotape and scales of hand activity level (HAL) and normalized peak of force (PF) proposed by the American Conference of Governmental Industrial Hygienists (ACGIH): supermarket cashier job tasks resulted on the threshold limit value line, confirming high biomechanical risk factors for CTS. Both symptoms and case prevalence resulted higher in supermarket cashiers than in control group and in full time cashiers if compared with part time ones. This difference between groups of part-/full-time cashiers could be due to total hours of exposure during the week and/or to the amount of recovery time between work sessions. Further longitudinal study could give more information about the role of different biomechanical risk factors in the onset of cumulative trauma disorders of the upper limb.

Adult↗
PubMedDate not supplied

A long-lasting pandemic: diseases caused by dust containing silica: Italy within the international context.

Diseases caused by dust containing silica represent an exemplary case study in the field of work-related diseases and in the history of the discovery of chronic industrial disease and its relationship to industrial society. Both dust and steam are indissolubly linked to the Industrial Revolution which everywhere was expected to replace slaves with masses of proletarians alike lesser gods. The identification of different nosological entities of dust-related diseases, the discovery that the most harmful dust particles in gold mines were invisible, insurance compensation and the development of the silicosis threshold limit value were all subjects of intense political negotiation that accompanied, with the connivance of doctors and scientists, a compromise between the health of workers and the economic health of industry. The preference for damage compensation (insurance system) over risk prevention (industrial hygienic measures) was also asserted and maintained in post-war Italy. Decline and modification of silicosis in Italy proceeded at the same rate as the introduction and subsequent application of more effective preventative legislation, especially with the protest movements of the working class at the end of the 1960s, together with the elimination of entire sectors of industrial activities, first those specialising in extraction and then the metallurgy.

Cultural Evolution↗
PubMed2005

[Field study of concentrations and emissions of particulate contaminants by types of swine houses in Korea].

OBJECTIVES: Particulate contaminants, such as total and respirable dusts, can harm the health of farm workers via several routes. The principal aims of this field study were to determine the concentrations and emissions of particulate contaminants: total and respirable dusts, in the different types of swine houses used in Korea, and allow objective comparison between Korea and the other countries in terms of swine housing types. METHODS: The swine houses investigated in this research were selected with respect to three criteria: the manure removal system, ventilation mode and growth stage of pigs. Measurements of total and respirable dust concentrations and emissions in the swine houses were carried out on 5 housing types at 15 different farm sites per housing type. The swine houses investigated were randomly selected from farms situated within the central districts in Korea: province of Kyung-gi, Chung-buk and Chung-nam. RESULTS: The total and respirable dust concentrations in the swine houses averaged 1.88 and 0.64 mg/m3, ranging from 0.53 to 4.37 mg/m3 and from 0.18 to 1.68 mg/m3, respectively. The highest concentrations of total and respirable dusts were found in the swine houses with deep-litter bed systems: 2.94 mg/m3 and 1.14 mg/m3, while the lowest concentrations were found in the naturally ventilated buildings with slats: 0.83 mg/m3 and 0.24 mg/m3, respectively (p<0,05). All the swine houses investigated did not exceed the threshold limit values (TLVs) for total (10 mg/m3) and respirable (2.5 mg/m3) dusts. The mean emissions of total and respirable dusts, per pig (75 kg in terms of live weight) and area (m2), from the swine houses were 97.33 and 9.55 mg/h/pig and 37.14 and 12.83 mg/h/ m2, respectively. The swine houses with deep-litter bed systems showed the highest emissions of total and respirable dusts (p<0.05). However, the emissions of total and respirable dusts from the other swine houses were not significantly different (p>0.05). CONCLUSION: The concentrations and emissions of total and respirable dusts were relatively higher in the swine houses managed with deep-litter bed systems and ventilated naturally of the different swine housing types tested. In further research, more farms than the number used in this research should be investigated, which will present objective and accurate data on the concentrations and emissions of total and respirable dusts in Korean swine houses. In addition, personal sampling should be performed to objectively assess the exposure level of farm workers to particulate contaminants.

Agriculture↗
PubMed1991

Validity of salivary thiocyanate as an indicator of cyanide exposure from smoking.

The purpose of this study was to evaluate the validity of salivary thiocyanate as an indicator of cyanide exposure from smoking. The salivary thiocyanate level showed wide variation, and the largest source of thiocyanate was hydrogen cyanide from cigarette smoke. Hydrogen cyanide in the mainstream of cigarette smoke was as high as 40-70 ppm, which is beyond the threshold limit value for occupational health (10 ppm). The hydrogen cyanide level in the sidestream smoke was lower less than 5 ppm. Thus the amount of cyanide intake was larger in active smokers than in passive ones. The correlation between the thiocyanate level in saliva and plasma was statistically significant. Thiocyanate levels in both plasma and saliva increased with the amount of cigarette smoke, and the discriminant powers (smoker versus non smoker) of thiocyanate levels in both plasma and saliva were quite similar. The smoker/non smoker ratio for salivary thiocyanate was 3.04 and that of plasma thiocyanate was 1.73. The result indicated that smoking status could be reflected more by the thiocyanate level in saliva than in plasma. The biological half life of salivary thiocyanate was estimated to be as long as 9.5 days from the changes salivary thiocyanate after stopping smoking. From the results of this study, it was concluded that salivary thiocyanate was a suitable indicator of habitual smoking exposure.

Humans↗
PubMedDate not supplied

Health hazards and nitrous oxide: a time for reappraisal.

Recent adoption by the American Conference of Governmental Industrial Hygienists of a Threshold Limit Value of 50 ppm for an 8-hour average exposure to nitrous oxide (N2O) increases the likelihood for its regulation by state and federal occupational health agencies. This review outlines current information on the health risks of N2O inhalation to provide a basis from which safe and reasonably attainable exposure limits can be proposed. Although N2O was for many years believed to have no toxicity other than that associated with its anesthetic action, bone marrow depression in patients administered N2O for extended periods of time and neurological abnormalities in health care workers who inhaled N2O recreationally have disproved this notion. Retrospective surveys of dental and medical personnel have also linked occupational exposure to N2O with a number of health problems and reproductive derangements. Nitrous oxide reacts with the reduced form of vitamin B12, thereby inhibiting the action of methionine synthase, an enzyme that indirectly supports methylation reactions and nucleic acid synthesis. Many, if not all, of the nonanesthetic-related adverse effects of N2O may be ascribed to this action. Animal and human studies indicate that the toxic effects of N2O are concentration- and time-dependent. It is suggested that a time-weighted average of 100 ppm for an 8-hour workday and/or a time-weighted average of 400 ppm per anesthetic administration would provide adequate protection of dental personnel and be achievable with existing pollution control methods.

5-Methyltetrahydrofolate-Homocysteine S-Methyltran↗