bluuebunny/crossref_metadata_2025 huggingface dataset:
Neurotoxicity among pesticide applicators exposed to organophosphates.
Authors: Stokes L , Stark A , Marshall E , Narang A
Published: December 2008

OBJECTIVES--An epidemiological study of 90 male pesticide applicators licensed in New York was conducted to investigate the effect of exposure to organophosphate pesticides on the peripheral nervous system. METHODS--A cohort of farmers and pesticide applicators from New York State were questioned off season (November 1988-February 1989) and again during the spraying season (April 1989-August 1989) about the presence of several acute signs and symptoms. Short term exposure was validated by measuring the concentration of dimethylthiophosphate (DMTP), a metabolite of guthion, in urine. Chronic signs of subtle peripheral nerve damage were determined by vibration threshold sensitivity of the farmers and applicators tested during November 1988-February 1989 and compared with controls drawn from the general population who were tested during the same time period the next year (November 1989-February 1990). Vibration threshold sensitivity was determined for both the hands and feet. Long term exposure to pesticides was determined by questionnaire. RESULTS--Paired t tests show that mean vibration threshold scores were significantly higher for the dominant (P < 0.00) and non-dominant (P < 0.04) hands among pesticide applicators when compared with scores for population based controls individually matched on age, sex, and county of residence. CONCLUSIONS--A significant increase in mean vibration threshold sensitivity for the dominant and non-dominant hand suggests previous organophosphate exposure among pesticide applicators was associated with a loss of peripheral nerve function.
Hepatic ultrasonic changes in workers exposed to perchloroethylene.
Authors: Brodkin C A , Daniell W , Checkoway H , Echeverria D , Johnson J , Wang K , Sohaey R , Green D , Redlich C , Gretch D
Published: December 2008

OBJECTIVE--To determine if subclinical hepatotoxicity is associated with exposure to perchloroethylene at concentrations commonly experienced in the workplace, and whether surveillance with serum hepatic transaminase activity underestimates such effects. METHODS--Hepatic parenchymal echogenicity on ultrasonography and serum hepatic transaminase activity were compared in 29 community based dry cleaning operators exposed to perchloroethylene, and a control group of 29 non-exposed laundry workers. Perchloroethylene exposure was assessed by work history and air monitoring. RESULTS--Mean hepatic transaminase activities were minimally increased in dry cleaners compared with laundry workers. Increased alanine aminotransferase activities, between 1.0 and 1.5 times the normal limits, were found in five of 27 (19%) dry cleaners compared with one of 26 (4%) laundry workers. In contrast, diffuse parenchymal changes in echogenicity, as determined by hepatic ultrasonography, were increased nearly twofold in dry cleaners, occurring in 18 of 27 (67%) dry cleaners compared with 10 of 26 (39%) laundry workers (P < 0.05), and were most strongly associated with increased perchloroethylene exposure in older dry to dry or wet transfer operations (odds ratio 4.2, 95% confidence interval 1.1-15.3). Mean eight hour time weighted average perchloroethylene exposure for dry cleaners was 16 ppm, which is less than the permissible exposure limit of 100 ppm in the United States. CONCLUSIONS--It was concluded that mild to moderate hepatic parenchymal changes occur more frequently in workers exposed to perchloroethylene than in populations not exposed to chemical solvents, and that these effects are underestimated by serum hepatic transaminase activity.
Reports of work related musculoskeletal injury among home care service workers compared with nursery school workers and the general population of employed women in Sweden.
Authors: Ono Y , Lagerström M , Hagberg M , Lindén A , Malker B
Published: December 2008

OBJECTIVES--To describe the nationwide occurrence of work related musculoskeletal injuries among all home care service workers in Sweden, and to identify relative risks and risk factors of the injuries. METHODS--The study was based on work related injuries reported to the Swedish occupational injury information system in 1990-1. The work related musculoskeletal injuries were divided into overexertion accidents and musculoskeletal diseases. The incidence of the injuries in female home care service workers was compared with those in nursery school workers and all other employed women in Sweden. RESULTS--In home care service workers, the annual incidence of injury from overexertion accidents and musculoskeletal diseases were 19.2 and 15.1 per 1000 workers, respectively, which was higher than those in nursery school workers and all employed women in Sweden. For five injury locations including the back, all the age standardised relative risks (SRR) of overexertion accidents exceeded 4.0, and most of those for musculoskeletal diseases were 1.5 or more in home care service workers compared with all other employed women in Sweden. Total duration of sick leave due to overexertion accidents was 7.7 times, and musculoskeletal diseases 3.5 times, longer than in nursery school workers. National loss due to sick leave resulting from only musculoskeletal injuries in home care service workers was about 8.2% of the total work related sick leave in all employed women in Sweden, although the number of home care service workers represented only some 5% of this population. Lifting other people was most frequently reported as the main risk cause of overexertion accidents in both kinds of workers. CONCLUSIONS--The results support the hypothesis that home care service workers have higher annual injury incidence of musculoskeletal injuries than nursery school workers due to physically stressful tasks that are far less common in nursery school workers.
Ventilation rate in office buildings and sick building syndrome.
Authors: Jaakkola J J , Miettinen P
Published: December 2008

OBJECTIVE--To examine the relation between ventilation rate and occurrence of symptoms of the eyes, nose, throat, and skin as well as general symptoms such as lethargy and headache, often termed the sick building syndrome. METHODS--A cross sectional population based study was carried out in 399 workers from 14 mechanically ventilated office buildings without air recirculation or humidification, selected randomly from the Helsinki metropolitan area. The ventilation type and other characteristics of these buildings were recorded on a site visit and the ventilation in the rooms was assessed by measuring the airflow through the exhaust air outlets in the room. A questionnaire directed at workers inquired about the symptoms and perceived air quality and their possible personal and environmental determinants (response rate 81%). The outcomes were weekly work related symptoms experienced during the previous 12 months and symptom groups defined either by their anatomical location or hypothesised mechanism. RESULTS--In logistic regression analysis, the adjusted odds ratio (OR) for any symptom of interest was 3.03 (95% confidence interval (95% CI) 1.13 to 8.10) in the very low ventilation category of below 5 l/s per person and 2.24 (0.89 to 5.65) in the high ventilation category of over 25 l/s per person compared with the reference (15- < 25 l/s). The ORs for ocular (1.27, 1.11 to 1.46), nasal (1.17, 1.06 to 1.29), skin symptoms (1.18, 1.05 to 1.32), and lethargy (1.09, 1.00 to 1.19) increased significantly by a unit decrease in ventilation from 25 to 0 l/s per person. CONCLUSION--The results suggest that outdoor air ventilation rates below the optimal (15 to 25 l/s per person) increase the risk of the symptoms of sick building syndrome with the sources of pollutants present in mechanically ventilated office buildings. The Finnish guideline value is 10 l/s per person.
Substantial decrease of blood lead in Swedish children, 1978-94, associated with petrol lead.
Authors: Strömberg U , Schütz A , Skerfving S
Published: December 2008

OBJECTIVES--To study the potential impact of environmental exposure to petrol lead, residential area, age, sex, and lead exposing hobby, on blood lead concentrations (BPb) in children. METHODS--In the south of Sweden, yearly from 1978-94, BPb was measured in 1230 boys and 1211 girls, aged between 3 and 19 (median 10; quartiles 9 and 12) years. RESULTS--For the samples of 1978, the geometric mean (GM) was 67 (range 30-250) micrograms/l in boys and 53 (18-161) micrograms/l in girls, whereas the corresponding GMs for 1994 were 27 (12-122) and 23 (12-97) micrograms/l. The sex difference was present only in children over eight. Moreover, residential area affected BPb; in particular, children living near a smelter area had raised BPbs. There was a clear ecological relation between BPb (adjusted GM) and annual lead quantity in petrol sold in Sweden, which was estimated to be 1637 tonnes in 1976 and 133 tonnes in 1993 (P < 0.001, ecological linear regression analysis, where a two year lag of petrol lead was applied). In the 171 boys and 165 girls who were sampled twice with an interval of one to four years, the decreases in BPb were estimated to be 6% (95% confidence interval 4%-8%) and 10% (8%-13%)/year, respectively. CONCLUSIONS--The present report points out the considerable beneficial effect of the gradual banning of petrol lead on the lead exposure affecting the population and differential sex specific BPb patterns due to a pronounced age effect in girls, which may be caused by older girls' lower food intake per kg of body weight, lower lung ventilation, cleaner life style, and loss of blood lead through menstrual bleedings.
Chronic effects of welding exposure on pulmonary function tests and respiratory symptoms.
Authors: Ozdemir O , Numanoğlu N , Gönüllü U , Savaş I , Alper D , Gürses H
Published: December 2008

OBJECTIVES--The respiratory effects of exposure to welding fumes have been investigated in numerous studies; but results of these studies have not been consistent. The aim of the present study was to investigate the respiratory effects of welding exposure in a large group of manual are welders exposed primarily to mild steel welding processes in confined spaces without respiratory protection. METHODS--Respiratory symptoms and spirometry were studied in 110 welders and 55 controls. The welders and controls were of similar average age and height; smoking habits of the groups were similar. Chest x ray films were taken to exclude people with radiological abnormalities that may influence pulmonary function tests. Welders were grouped according to smoking habits and duration of employment (< 20 years or > 20 years). RESULTS--No gross radiological abnormalities were found. Respiratory symptoms and chronic bronchitis were more prevalent in welders (P < 0.05). Welders who were smokers showed a higher frequency of chronic bronchitis than controls who smoked (P < 0.05). No significant difference in the occurrence of chronic bronchitis was found between welders who smoked and welders who were non-smokers or exsmokers. Compared with the controls, forced vital capacity (FVC), forced expiratory volume in one second (FEV1), peak expiratory flow (PEF), and maximum midexpiratory flow (MMEF) were significantly lower in welders (mean values of FVC for welders and controls were 86.06 (25.74) and 96.40 (13.03); and values for FEV1 were 87.54 (13.70) and 95.36 (12.40) respectively; P < 0.01). There was no significant difference in pulmonary function tests between welders who were non-smokers and controls who were non-smokers; whereas FVC, FEV1, PEF, and MMEF were significantly lower in welders who smoked than controls who smoked (P < 0.01). There were no significant differences in pulmonary function tests and occurrence of chronic bronchitis between welders with more or less than 20 years at work. CONCLUSION--Welders working in conditions of inadequate ventilation, have increased risk of chronic bronchitis and impairment of pulmonary function.
A pilot study of the effect of low level exposure to mercury on the health of dental surgeons.
Authors: Ritchie K A , Macdonald E B , Hammersley R , O'Neil J M , McGowan D A , Dale I M , Wesnes K
Published: December 2008

OBJECTIVES--This project was conducted to examine whether the computerised analysis of psychomotor responses available from Cognitive Drug Research is appropriate for measuring an effect of low level exposure to mercury in dentists. METHODS--A computerised battery of psychomotor tests was given to two groups of dentists (older dentists and trainees) and to two age matched control groups. As well as the psychomotor tests, volunteers were required to complete a questionnaire to identify potential influences on psychomotor performance and to provide a sample for analysis of urinary mercury. RESULTS--Statistical analysis of the results showed that the older dentists had slightly higher concentrations of urinary mercury although most were around background levels and they were all within occupational limits. Five of the psychomotor tests showed no differences between the performance of the four groups. The older dentists showed significantly better performance on the simple reaction time test and significantly poorer performance in the immediate word recall and delayed word recall tests. CONCLUSIONS--Poorer performance in memory recall tests confirms previously reported studies. This together with the confirmation that this test system is a practical tool in the occupational setting suggests that a larger study of the effects of mercury exposure on dentists would be appropriate.
Some altered concentrations of elements in semen of workers exposed to trinitrotoluene.
Authors: Liu H X , Qin W H , Wang G R , Yang Z Z , Chang Y X , Jiang Q G
Published: December 2008

OBJECTIVES--A cross sectional study was performed to find the concentrations of elements contained in the semen of workers exposed to trinitrotoluene (TNT). SUBJECTS AND METHODS--Semen of exposed workers in two TNT plants located in He-Nan Province in 1992 were examined. RESULTS--The average TNT concentrations in the workplace, except the packing site, were found to have exceeded the maximal allowable concentration (MAC, 1 mg/m3); skin contaminations of male workers exposed to TNT were higher after a shift than in controls, and correlated with the total blood concentrations of TNT, 4-amino-2, 6-dinitrotoluene (4A), and 2-amino-4, 6-dinitrotoluene (2A). Cu, Zn, Na, Mg, and Se concentrations were significantly decreased, but K, Ca, Co, Mn and Li contents were not significantly changed in the semen of workers exposed to TNT. Compared with the control group, the percentage of liquifying time of semen, the sperm malformation incidence, and viability in the men exposed to TNT were all significantly changed. CONCLUSIONS--Men exposed to TNT have decreased concentrations of some elements is semen and altered semen physiology.
Are the respiratory health effects found in manufacturers of ceramic fibres due to the dust rather than the exposure to fibres?
Authors: Burge P S , Calvert I A , Trethowan W N , Harrington J M
Published: December 2008

OBJECTIVES--To determine whether the respiratory symptoms and decrements in lung function found in manufacturers of ceramic fibres are related to exposure to the respirable fibre or inspirable mass constituents of the air in the working environment. METHODS--Cross sectional survey of all current European primary producers of ceramic fibre was carried out, with measurement of exposure to respiratory fibres by personal samplers that measured inspirable and total mass, together with a health survey with an expanded respiratory questionnaire and standardised measurement of lung function. Odds ratios were calculated for symptoms and current exposure by multiple logistic regression, and multiple linear regression coefficients for lung function related to cumulative exposures controlled for the effects of respirable fibre and inspirable mass separately and together. RESULTS--Significant effects of current exposure to both inspirable dust and respirable fibres were related to dry cough, stuffy nose, eye and skin irritation and breathlessness. The decrements found in smokers and to some extent in ex-smokers in forced expiratory volume in one second and forced expiratory flow from 25% to 75% of expiratory volume, seem to be related to the respirable fibres rather than the inspirable mass constituents of the environment. CONCLUSIONS--Current symptoms were related to both current exposure to inspirable dust and respirable fibre. The decrements in lung function were related to the fibre constituent of the exposure.
Neuropathy in female dental personnel exposed to high frequency vibrations.
Authors: Akesson I , Lundborg G , Horstmann V , Skerfving S
Published: December 2008

OBJECTIVE--To evaluate early neuropathy in dental personnel exposed to high frequency vibrations. METHODS--30 dentists and 30 dental hygienists who used low and high speed hand pieces and ultrasonic scalers were studied, and 30 dental assistants and 30 medical nurses not exposed to vibration (all women). Vibrotactile sensibility, strength, motor performance, sensorineural symptoms and signs, and vascular symptoms in the hands, as well as mercury concentrations in biological samples and cervicobrachial symptoms, were studied. RESULTS--The two groups exposed to vibration had significant impairments of vibrotactile sensibility, strength, and motor performance, as well as more frequent sensorineural symptoms. In the dentists there were significant associations between the vibrotactile sensibility and strength, motor performance, superficial sensibility, and sensorineural symptoms. There were no associations between these findings and cervicobrachial symptoms, mercury concentrations, or smoking. There was no increase of vascular symptoms of the hands in the groups exposed to vibration. CONCLUSION--Dental hygienists and dentists had a slight neuropathy, which may be associated with their exposure to high frequency vibrations, and which may be detrimental to their work performance. Thus, development of safer equipment is urgent.
Cost and determinants of morbidity from work related disabling injuries in Taiwan.
Authors: Liu Y H , Lin M R , Wang J D
Published: December 2008

OBJECTIVES--To estimate the cost and determinants of morbidity from work related disabilities. METHODS--114 people who lived in metropolitan Taipei and who had received disability compensation from the Labor Insurance Bureau from March to June, 1991 were randomly selected. There were 77 workers interviewed through a questionnaire that inquired about possible loss of productivity including the duration of morbidity, the ability to return to work, and any change in monthly income upon returning to work. RESULTS--The mean (SD) duration of a stay in hospital was 29 (39) days, median: 15 days. The average duration between discharge from the hospital and returning to work was 111 (146) days, median: 45 days. The main determinants of the duration of the stay in hospital were the number of stays in hospital and the severity of the injury. A multivariate linear analysis showed that old age and the severity of injury determine the durations of morbidity. An ordinal logistic regression analysis showed that the severity of injury, size of the factory, and age determined the magnitude of future productivity loss. Based on these models, it was estimated that the total duration of morbidity (in hospital and at home) due to occupational disability was 660,000 person-days each year. When the percentage of the decrease in income because of permanent disability was converted into a loss of work days, the annual morbidity costs were about 19,000-26,000 person-years between 1985-1990. CONCLUSION--The morbidity cost was about five times as high as the lump sum payment that a worker usually received for disability compensation. We conclude that morbidity cost should be evaluated carefully in the future for the establishment of accurate and fair disability compensation payments.
Cancer and occupational exposure to inorganic lead compounds: a meta-analysis of published data.
Authors: Fu H , Boffetta P
Published: December 2008

OBJECTIVES--To review and summarise the epidemiological evidence on the carcinogenicity of occupational exposure to inorganic lead. METHODS--Case-control and cohort studies were reviewed and combined for meta-analysis. Fixed and random effect methods were used to estimate the summary effects. RESULTS--The combined results show a significant excess risk of overall cancer, stomach cancer, lung cancer, and bladder cancer, with relative risk ratios (RRs) and 95% confidence intervals (95% CIs) in the meta-analysis of 1.11 (1.05-1.17), 1.33 (1.18-1.49), 1.29 (1.10-1.50), and 1.41 (1.16-1.71) respectively. The RR (95% CI) for kidney cancer was also high, but did not reach significance (1.19 (0.96-1.48)). A separate analysis of studies of heavily exposed workers provided slightly increased RRs for cancers of the stomach (1.50) and lung (1.42). CONCLUSIONS--The findings from the workers with heavy exposure to lead provided some evidence to support the hypothesis of an association between stomach and lung cancer and exposure to lead. The main limitation of the present analysis is that the excess risks do not take account of potential confounders, because little information was available for other occupational exposures, smoking, and dietary habits. To some extent, the risk of lung cancer might be explained by confounders such as tobacco smoking and exposure to other occupational carcinogens. The excess risk of stomach cancer may also be explained, at least in part, by non-occupational factors. For bladder and kidney cancers, the excess risks are only suggestive of a true effect because of possible publication bias.
Study of the respiratory health of employees in seven European plants that manufacture ceramic fibres.
Authors: Trethowan W N , Burge P S , Rossiter C E , Harrington J M , Calvert I A
Published: December 2008

OBJECTIVES--To study the relation between occupational exposure to ceramic fibres during manufacture and respiratory health. METHODS--The respiratory health of 628 current employees in the manufacture of ceramic fibres in seven European plants in three countries was studied with a respiratory questionnaire, lung function tests, and chest radiography. Simultaneous plant hygiene surveys measured subjects' current exposure to airborne ceramic fibres from personal samples with optical microscopy fibre counts. The measured exposures were combined with occupational histories to derive estimates of each subject's cumulative exposure to respirable fibres. Symptoms were related to current and cumulative exposure to ceramic fibres and lung function and findings from chest radiographs were related to cumulative exposure. RESULTS--The mean duration of employment was 10.2 years and mean (range) cumulative exposure was 3.84 (0-22.94) (f.ml-1.y). Eye and skin symptoms were frequent in all plants and increased significantly, as did breathlessness and wheeze, with increasing current exposure. Dry cough and stuffy nose were less common in the least exposed group but did not increase with increasing exposure. After adjustment for the effects of age, sex, height, smoking, and past occupational exposures to respiratory hazards, there was a significant decrease in both forced expiratory volume in one second (FEV1) and forced midexpiratory flow related to cumulative exposure in current smokers (P < 0.05) and in FEV1 in ex-smokers (P < 0.05). Small opacities were found in 13% of the chest radiographs; their prevalence was not related to cumulative exposure to ceramic fibres. CONCLUSIONS--It is concluded that exposure to ceramic fibres is associated with irritant symptoms similar to those seen in other exposures to man made mineral fibres (MMMFs) and that cumulative exposure to respirable ceramic fibres may cause airways obstruction by promoting the effects of cigarette smoke.
Sex ratios of births, mortality, and air pollution: can measuring the sex ratios of births help to identify health hazards from air pollution in industrial environments?
Authors: Williams F L , Ogston S A , Lloyd O L
Published: December 2008

OBJECTIVES--To compare the sex ratios of births and mortality in 12 Scottish localities with residential exposure to pollution from a variety of industrial sources with those in 12 nearby and comparable localities without such exposure. METHODS--24 localities were defined by postcode sectors. SMRs for lung cancer and for all causes of death and sex ratios of births were calculated for each locality for the years 1979-83. Log linear regression was used to assess the relation between exposure, sex ratios, and mortality. RESULTS--Mortalities from all causes were consistently and significantly higher in the residential areas exposed to air pollution than in the non-exposed areas. A similar, but less consistently significant, excess of mortality from lung cancer in the exposed areas was also found. The associations between exposure to the general air pollution and abnormal sex ratios, and between abnormal sex ratios and mortality, were negligible. CONCLUSIONS--Sex ratios were not consistently affected when the concentrations or components of the air pollution were insufficiently toxic to cause substantially increased death rates. Monitoring of the sex ratio does not provide a reliable screening measure for detecting cryptic health hazards from industrial air pollution in the general residential environment.
Influence of indoor air quality and personal factors on the sick building syndrome (SBS) in Swedish geriatric hospitals.
Authors: Nordström K , Norbäck D , Akselsson R
Published: December 2008

OBJECTIVES--Sick building syndrome (SBS) involves symptoms such as irritation to the eyes, skin, and upper airways, headache, and fatigue. The relations between such symptoms and both personal and environmental factors were studied in 225 female hospital workers, working in eight hospital units in the south of Sweden. METHODS--Symptoms of SBS and personal factors were measured by means of a standardised self administered questionnaire. The technical investigation comprised a building survey and measurements of room temperature, supply air temperature, air humidity, and exhaust air flow. RESULTS--The prevalence of symptoms differed from one unit to another. The mean value of weekly complaints of fatigue was 30%, of eye irritation 23%, and of dry facial skin 34%. Eye irritation was related to work stress, self reported exposure to static electricity, and was also more common in buildings with a high ventilation flow and a high noise level (55 dB(A)) from the ventilation system. Nasal symptoms were related to asthma and hay fever only. Throat symptoms were more common in smokers, subjects with asthma or hay fever, new buildings, and in buildings with a high ventilation flow. Facial skin irritation was related to a lack of control of the work conditions, and was more common in new buildings, and buildings with a high ventilation flow and ventilation noise. General symptoms, such as headache and fatigue, were related to current smoking, asthma or hay fever, work dissatisfaction, and static electricity. CONCLUSION--As the prevalence of symptoms was high, there is a need to improve the indoor environment as well as the psychosocial environment in hospitals. These improvements could include a reduction of ventilation noise, minimised smoking, and improvements in the psychosocial climate. Further research is needed to identify indoor climatic factors that cause the increased prevalence of symptoms of SBS in new buildings.
Association between NAG-B and cadmium in urine with no evidence of a threshold.
Authors: Bernard A , Thielemans N , Roels H , Lauwerys R
Published: December 2008

OBJECTIVES--To explore the significance of the increase in urinary excretion of the lysosomal enzyme beta-N-acetylglucosaminidase (NAG) at low exposures to cadmium (Cd) that is frequently found in the absence of any other sign of renal dysfunction. METHODS--The activity was measured of the two main isoenzymes of NAG (NAG-A secreted by exocytosis and NAG-B released with cell membranes) in the urine of 49 male workers employed in a Cd smelter and of 20 age matched controls. RESULTS--An increased urinary excretion of low molecular weight proteins was noted only in subjects who excreted > 10 micrograms Cd/g creatinine. The urinary activity of NAG-B showed a dose related increase that was already significant in the group excreting 0.5-2 micrograms Cd/g creatinine. In multiple regression analysis the NAG-B activity correlated with the excretion of Cd but not with that of lead or mercury. The NAG-A activity was by contrast unaffected by exposure to Cd but correlated with the urinary excretion of lead and copper. CONCLUSIONS--As NAG-B is considered to be the lesional form of NAG, the existence of a specific association between this enzyme and urinary Cd excretion with no detectable threshold suggests that this metal produces cellular alterations at exposures commonly found in the general population.
Cancer incidence and mortality near the Baglan Bay petrochemical works, South Wales.
Authors: Sans S , Elliott P , Kleinschmidt I , Shaddick G , Pattenden S , Walls P , Grundy C , Dolk H
Published: December 2008

OBJECTIVES--To study incidence and mortality of leukaemias, cancer of the larynx, and other cancers near the petrochemical plant at Baglan Bay, in response to local concerns of an alleged cluster of cancers in the vicinity. METHODS--This is a small area study of cancer incidence, 1974-84 and of mortality, 1981-91 based on the national postcoded data held by the Small Area Health Statistics Unit and with population and socioeconomic data from the 1981 census. The study is centred on BP Chemicals Ltd, Baglan Bay, Port Talbot, West Glamorgan, South Wales and includes a general population sample of 115,721 people (1981 census) living within 7.5 km of the plant. Cancer incidence and mortality for all cancers, leukaemias, and cancer of the larynx were examined within 7.5 km and 3 km of the plant, and tests for decline in risk of these cancers with distance from the plant were carried out. Mortality from several other cancers possibly associated with the petrochemical industry was also studied. RESULTS--There were 5417 incident cancer cases and 2458 cancer deaths within 7.5 km of the plant during the periods of study. There was an 8% excess incidence of all cancers within 7.5 km, and a 24% excess of cancer of the larynx, consistent with a general excess of these cancers in West Glamorgan, but no apparent decline in incidence with distance from the plant, nor excess mortality. There was also no evidence of decline in leukaemia incidence or mortality with distance, at all ages or in children. Among the other causes included in the mortality study, there was an excess of multiple myeloma within 7.5 km, especially among women, and a significant decline in mortality from non-Hodgkin's lymphomas although there was no excess overall within 7.5 km. CONCLUSIONS--The apparent excess incidence of all cancers and cancer of the larynx within 7.5 km of the BP Chemical Ltd works was consistent with an excess more generally in West Glamorgan, possibly related, at least to some extent, to cancer registration in Wales. There was no excess mortality from these cancers. The results for multiple myeloma and especially non-Hodgkin's lymphomas may have been chance findings in view of the multiple tests of significance carried out in the study. A study of lymphatic and haematopoietic cancers near oil refineries in Great Britain is to be undertaken that will help put the findings of the present study in wider context.
Incidence of leukaemia and lymphoma in young people in the vicinity of the petrochemical plant at Baglan Bay, South Wales, 1974 to 1991.
Authors: Lyons R A , Monaghan S P , Heaven M , Littlepage B N , Vincent T J , Draper G J
Published: December 2008

OBJECTIVE--To determine whether there was an increased incidence of leukaemias and lymphomas in young people aged less than 25 years in the locality of a petrochemical plant at Baglan Bay, South Wales. METHODS--Geographical population based study to compare the observed and expected incidence of leukaemia and lymphoma with onset before the age of 25, in the years 1974 to 1991. The population was aged 0-24 years and lived within 1.5 and 3 km of the plant. The observed number of cases in various categories were compared with the expected numbers of cases calculated from the Welsh cancer registration rates. RESULTS--Although the observed numbers were generally greater than would be expected, none of the comparisons showed significant excess of leukaemias or lymphomas for any period of years. CONCLUSIONS--The study shows that the incidence of leukaemias and lymphomas in children and young people in the area around the BP Chemical site at Baglan Bay, South Wales, between the years 1974 and 1991 was not significantly greater than normal.
Chest radiography and high resolution computed tomography in the evaluation of workers exposed to silica dust: relation with functional findings.
Authors: Talini D , Paggiaro P L , Falaschi F , Battolla L , Carrara M , Petrozzino M , Begliomini E , Bartolozzi C , Giuntini C
Published: December 2008

OBJECTIVES--To compare the usefulness of high resolution computed tomography (HRCT) with chest radiography (CR) in the diagnosis and assessment of severity of silicosis. METHODS--27 workers exposed to silica underwent CR, HRCT, and pulmonary function tests. Two experienced readers independently evaluated CR by International Labour Office classification, and grouped the results into four categories. HRCT categories of nodule profusion and the extent of emphysema were graded on a four point scale; in 20 subjects the percentage distribution of lung densities were measured by HRCT. RESULTS--Concordance between readers was higher for HRCT than for CR (K statistic = 0.49 and 0.29 respectively). There was poor concordance between CR and HRCT in the early stage of silicosis. No significant difference in pulmonary function tests was found among different CR categories, but forced expiratory volume in one second (FEV1), maximal expiratory flow at 50% and 75% of FVC (MEF50, MEF75), and diffusion capacity significantly decreased with increasing HRCT categories. Subjects with simple silicosis detected by HRCT had a lower FEV1 than subjects without silicosis, whereas subjects with conglomerated silicosis showed higher residual volume and functional residual capacity than subjects with simple silicosis. These relations were not affected by smoking or symptoms of chronic bronchitis. Different grades of emphysema detected by HRCT were significantly different in diffusion capacity. Only the HRCTs of the lowest and the highest categories of profusion of parenchymal opacities were significantly different in their distribution of density classes. CONCLUSION--HRCT is more reproducible and accurate than CR, as suggested by the higher agreement between readers and the better correlation with pulmonary function tests, irrespective of smoking and chronic bronchitis; however, these data do not support the hypothesis that HRCT is more sensitive than CR in the early detection of silicosis.
Physical work load and gestational age at delivery.
Authors: Koemeester A P , Broersen J P , Treffers P E
Published: December 2008

OBJECTIVE--To assess the impact of physical activity on the gestational age at delivery in women performing physical tasks in their jobs during pregnancy. METHODS--Qualified nurses at 15 weeks of pregnancy were asked through a questionnaire to describe the tasks in their regular job, the physical activities involved, and their exposure to other occupational stressors. The physical activities to be identified were walking, standing, lifting, stooping, squatting, and sitting. RESULTS--A high degree of daily physical work load during pregnancy seemed to be a significant predictor for the gestational age at delivery, whereas chemical and infectious agents were not. CONCLUSIONS--Physical work load during pregnancy should be diminished to avoid adverse effects on gestational age at delivery.
Dose-response relation between exposure to two types of hand-arm vibration and sensorineural perception of vibration.
Authors: Virokannas H
Published: December 2008

OBJECTIVES--31 railway workers and 32 lumberjacks were examined to compare the dose-response relation between the exposure to two types of hand-arm vibration and the sensory disturbances in peripheral nerves as evaluated by the vibration perception thresholds (VPTs). METHODS--Clinical examinations were carried out that included measurements of the VPTs, and electroneuromyography (ENMG), and an inquiry to confirm the use of vibrating tools. Diseases of the central nervous system and neuropathies were checked by inquiry and a clinical examination, diabetes was excluded by a blood sample analysis, and the subjects with carpal tunnel syndrome confirmed with ENMG were excluded from the study. RESULTS--Lifetime use of hand held tamping machines (railway workers) and chain saws (lumberjacks) had a significant correlation with the VPTs at frequencies from 32 to 500 Hz. The increase of the VPTs (250 Hz) in relation to use of vibrating tools was 1.8-fold higher on average in the whole group and 2.3-fold higher in the young (< 45) railway workers who had used hand held tamping machines, than in the corresponding groups of lumberjacks, who had used chain saws, whereas the frequency weighted acceleration of vibration in tamping machines was fourfold. CONCLUSION--There was a significant dose-response relation between the exposure to hand-arm vibration and the VPTs. The VPTs as a function of the frequency weighted acceleration of vibration and the exposure to vibration gave promising results for assessment of the risk of damage to sensory nerves induced by vibration.
Physiologically based pharmacokinetic model for acetone.
Authors: Kumagai S , Matsunaga I
Published: December 2008

OBJECTIVE--This study aimed to develop a physiologically based pharmacokinetic model for acetone and to predict the kinetic behaviour of acetone in the human body with that model. METHODS--The model consists of eight tissue groups in which acetone can be distributed: the mucous layer of the inhaled air tract, the mucous layer of the exhaled air tract, a compartment for gas exchange (alveolus of the lung), a group of blood vessel rich tissues including the brain and heart, a group of tissues including muscles and skin that have low perfusion rates, a group of fatty tissues, an organ for metabolism (liver), and a compartment for urinary excretion (kidney). A mucous layer in the model is only the outermost layer of the mucus lining the wall of the air tract during inhalation and exhalation. To check the relevance of the model, the simulated results were compared with the experimental data. Next, simulation was conducted by changing the volume of the mucous layer and the respiratory rate to clarify the effect of these variables. Finally, simulation of an occupational situation was performed. RESULTS--With an appropriate value for the volume of mucous layer, the simulated acetone concentrations in arterial blood, end exhaled air, urine, and fatty tissue were found to agree well with the experimental data. The volume of mucous layer and rate of respiration were critical for the appropriate simulation. The simulated occupational situation fitted the observed regression line in field studies quite well. The simulation also enabled predictions to be made about the characteristic kinetics for water soluble solvents. CONCLUSION--The model is useful for understanding and explaining the kinetics of acetone.
Risk of acute myeloid leukaemia and multiple myeloma in workers exposed to benzene.
Authors: Wong O
Published: December 2008

OBJECTIVE--To determine the risk of developing acute myeloid leukaemia (AML) and multiple myeloma in a cohort of workers exposed to benzene. The results were used to show the importance of taking specificity of disease into consideration in causation analysis. METHODS--Data were derived from a cohort of workers employed at two Goodyear plants in Ohio in the manufacture of Pliofilm. Based on data in the Pliofilm study, several papers that examined the relation between exposure to benzene and leukaemia (all cell types combined) have been published. In the current analyses based on updated data in the study, standardised mortality ratios (SMRs) and 95% confidence intervals (95% CIs) were calculated for AML and multiple myeloma by cumulative exposure to benzene. The results based on AML were compared with those for leukaemia (all cell types combined) published previously. RESULTS--An exposure response relation was shown between cumulative exposure to benzene and AML. No increased risk of AML was detected for cumulative exposure to benzene below 200 ppm-years (SMR 0.91). Above 200 ppm-years, risk of AML rose drastically; reaching a significant SMR of 98.37 for > 400 ppm-years. For multiple myeloma, no relation with exposure to benzene was detected. CONCLUSION--Analysis specific to AML shows the importance of taking specificity of disease into consideration in causation analysis. This investigation shows that previous analyses based on all leukaemia cell types combined have incorrectly set the estimated threshold too low, and have underestimated risk above the threshold. Current regulatory policies that rely on previous analyses based on all leukaemia cell types combined should be re-examined.
Effect of different exposure compounds on urinary kinetics of aluminium and fluoride in industrially exposed workers.
Authors: Pierre F , Baruthio F , Diebold F , Biette P
Published: December 2008

OBJECTIVE--To conduct a field study to obtain information on the urinary concentrations of aluminium (Al) and fluoride (F-) depending on the different compounds exposed to in the aluminum industry. METHODS--16 workers from one plant that produced aluminium fluoride (AlF3), and from two plants that produced aluminium electrolytically by two different processes participated in the study for one working week. Pollutants were monitored by eight hour personal sampling every day, and urine samples were collected during the week. Al and F- were analysed in both atmospheric and urine samples by atomic absorption spectrometry and an ion selective electrode. RESULTS--The principal results show different characteristics of kinetic curves of Al and F- excretion in workers with different exposures. Some characteristics of excretory peaks were linked to specific exposures--for instance, after exposure to AlF3 there was one delayed Al peak associated with one delayed F- peak about eight hours after the end of the daily shift, and after mixed exposure to HF and AlF3, two F- peaks were noted, one fast peak at the end of the shift and another delayed peak at 10 hours synchronised with an Al peak. In one of the electrolysis plants, the exposure to Al and F- compounds led to the simultaneous excretion of Al and F- peaks, either as a single peak or two individual ones depending on the type of technology used on site (open or enclosed potlines). The average estimated half life of Al was 7.5 hours, and of F- about nine hours. Quantitative relations between excretion and exposure showed an association between the F- atmospheric limit value of 2.5 mg/m3 with a urinary F- concentration of 6.4 mg/g creatinine at the end of the shift, a peak of 7.4 mg/g creatinine, and 7.4 mg excreted a day. For Al, the exposure to 1.36 mg/m3 during the shift corresponded to a urinary concentration at the end of the shift of 200 microgram/g creatinine. Daily excretion of 200 micrograms corresponded to an exposure to 0.28 mg/m3. CONCLUSION--Particular differences in the behaviour of Al and F- in urine depended upon the original molecular form in the pollutant. These results reinforce the principle that, in biological monitoring, the sampling strategy and the choice of limit value should be dependent on kinetic data that take the exposure compound of the element in question into account.
Combined electroneurographic and electromyographic studies in lead workers.
Authors: Yeh J H , Chang Y C , Wang J D
Published: December 2008

OBJECTIVES--To evaluate the effects of chronic exposure to lead on the peripheral nervous system in lead workers. METHODS--Nerve conduction velocity and electromyographic studies were performed on 31 lead workers of a battery recycling factory and 31 sex and age matched controls. 25 cases with mild distal extensor weakness of the upper limbs were classified as the lead neuropathy subgroup and the rest of the lead workers as the lead exposure subgroup. Blood lead concentrations and haematological and biochemical data were recorded. An index of cumulative exposure to lead was calculated by the summation of multiplying the average blood concentration of lead with the duration of exposure at various jobs. RESULTS--Compared with the control group, the distal motor latency of the median nerve was significantly prolonged in the lead neuropathy subgroup, but not in the exposure subgroup. Only six of 31 workers had nerve conduction abnormalities, whereas electromyographic evidence of denervation was found in 93.5% of the lead neuropathy subgroup and 83.5% in the lead exposure subgroup. The electromyographic abnormalities found were neurogenic polyphasic waves in all 29 workers with abnormal electromyographic findings (grade in seven cases and grade ++ in the rest). Spontaneous activity was only recorded in seven workers, with grade + in four and grade ++ in three. There was a positive linear correlation between the index of cumulative exposure to lead and the distal motor latencies of the tibial nerve as well as a negative correlation with conduction velocities of the sural nerve after multivariate analysis and control of potential confounding by age and sex. No correlation could be found between the electrophysiological values and a simple duration of exposure or concentration of blood lead. A non-parametric analysis showed that there was a trend of higher index of cumulative exposure to lead with more severe electromyographic changes. Electromyographic abnormality also occurred in workers with blood lead concentrations between 17.4 and 58 micrograms/dl. CONCLUSION--Electromyographic study in the distal extensors of the upper limbs may be used as a tool for biological monitoring of effect in lead workers.