Liver function alterations in synthetic leather workers exposed to dimethylformamide

A cross-sectional study of the prevalence of chronic liver function alterations was performed in 75 workers employed in a synthetic leather factory, exposed to dimethylformamide (DMF) air concentrations below threshold limit values (30 mg/m³). Biological monitoring among workers revealed acceptable urine levels of monomethylformamide (NMF) on average, but the very wide range indicated that occasional overexposure was possible. The worker survey showed a high percentage of disulfiram-like symptoms (50%) and liver function abnormalities (22.7%), compared with a demographically similar group of unexposed workers. Covariance analysis (ANCOVA) revealed that enzyme levels were significantly higher in exposed workers than in controls after data were corrected for age, alcohol consumption, body mass index, and cholesterol levels. The authors conclude that DMF can cause liver diseases even if air TLVs are respected, because accidental contact with liquid DMF can significantly increase DMF uptake. In this situation, air monitoring is no longer sufficient to evaluate worker exposure. Am. J. Ind. Med. 32:255-260, 1997. © 1997 Wiley-Liss, Inc.     

Changes in water vapor loss from the skin of metal industry workers monitored during exposure to oils

Vapor loss (VL) from nonsweating skin (SVL), a surrogate measure for transepidermal water passage, was ascertained electronically from 54 newly recruited metal workers. A weekly measurement was taken for 12 weeks from each worker in the three groups studied: 17 unexposed workers, 13 workers exposed to water-soluble oils and 24 workers exposed to straight mineral oil. During the 12-week period four workers in the group exposed to mineral oil developed contact dermatitis, with a markedly increased SVL. Among the 50 workers whose skin remained normal, the mean initial SVL was 6.8 g X m-2 X h-1 for the back of the hand, 4.4 for the extensor, and 4.7 for the volar forearm. There was a slight but nonsignificant increase in all three SVL levels in the group exposed to water-soluble oils as compared to the unexposed group. In the group exposed to mineral oils the SVL of the extensor and volar forearm rose to a significantly higher level as compared to those of the unexposed group. This difference persisted after statistical adjustment for age, sex, ethnic group, and initial SVL level. These findings indicate that SVL measurement has potential as a monitoring parameter for workers at risk of occupational contact dermatitis.     

Decreased serum free testosterone in workers exposed to high levels of di-n-butyl phthalate (DBP) and di-2-ethylhexyl phthalate (DEHP): a cross-sectional study in China

BACKGROUND: Observations of adverse developmental and reproductive effects in laboratory animals and wildlife have fueled increasing public concern regarding the potential for various chemicals to impair human fertility. OBJECTIVE: Our objective in this study was to assess the effect of occupational exposure to high levels of phthalate esters on the balance of gonadotropin and gonadal hormones including luteinizing hormone, follicle-stimulating hormone, free testosterone (fT), and estradiol. METHODS: We examined urine and blood samples of 74 male workers at a factory producing unfoamed polyvinyl chloride flooring exposed to di-n-butyl phthalate (DBP) and di-2-ethylhexyl phthalate (DEHP) and compared them with samples from 63 male workers from a construction company, group matched for age and smoking status. RESULTS: Compared to the unexposed workers, the exposed workers had substantially and significantly elevated concentrations of mono-n-butyl phthalate (MBP; 644.3 vs. 129.6 microg/g creatinine, p < 0.001) and mono-2-ethylhexyl phthalate (MEHP; 565.7 vs. 5.7 microg/g creatinine, p < 0.001). fT was significantly lower (8.4 vs. 9.7 microg/g creatinine, p = 0.019) in exposed workers than in unexposed workers. fT was negatively correlated to MBP (r = -0.25, p = 0.03) and MEHP (r = -0.19, p = 0.095) in the exposed worker group. Regression analyses revealed that fT decreases significantly with increasing total phthalate ester score (the sum of quartiles of MBP and MEHP; r = -0.26, p = 0.002). CONCLUSION: We observed a modest and significant reduction of serum fT in workers with higher levels of urinary MBP and MEHP compared with unexposed workers.     

The monitoring of cholinesterases in farm workers and tradesmen exposed to phosphoric esters and carbamates]

Cholinesterase (ChE) levels (Ellman method) were monitored in 90 subjects (69 males and 21 females) exposed to carbamate and organophosphate pesticides (78 agricultural workers and 12 pesticide vendors). Pre-exposure baseline values of plasma and red blood cell cholinesterase activities were defined for each subject with two blood samples (23 workers) or three blood samples (59 workers) taken almost thirty days after the last exposure. After control of intra-individual variation, 8 subjects with only one pre-exposure value and 13 with a coefficient of variation above 30% were excluded. For the other 59 subjects, the intra-individual variation of erythrocyte ChE (16%) was similar to the inter-individual one (15%), whereas the inter-individual variation of plasma ChE (21%) was higher than the intra-individual one (14%). Laboratory variation for plasma ChE measurements was 8%. Baseline values were analyzed (ANOVA) for sex, age, task and hour and season of sampling. Both erythrocyte and plasma enzymes, corrected for hematocrit, were lower in females. Plasma cholinesterase activity was lower in "re-entry" agricultural workers and in pesticide vendors. Post-exposure cholinesterase activity was measured in 54 workers within a few (1-21) days after last handling. Average relative reduction was 15.2% (95% C.I. = 4.9%-25.5%) in erythrocyte cholinesterase activity and 29.1% (95% C.I. = 18.2%-40.1%) in plasma cholinesterase activity. The one-way variance analysis showed marked plasma ChE reduction in mixers, loaders and appliers (36%, 95% C.I. = 24%-48%) and in parathion handlers (35%, 95% C.I. = 21%-49%. No significant reduction in blood cell cholinesterase activity in relation to task and to pesticide handled was observed. We conclude that the intra-individual variations of the baseline values were higher for three repetitions (88% and 84% of the population were within a variability of less than 30%, for AChE and for ChE respectively) than for two repetitions (91% and 88% of the population were within 30% of variability for AChE and for ChE respectively). The figures show a greater sensitivity of plasma ChE activity in acute exposure, probably due to a poor reliability in detection of erythrocyte ChE by local laboratories. The maximum reduction (38%, 95% C.I. = 22%-53%) in plasma ChE activity was observed within six days of the last exposure in loaders and appliers.     

Variability and determinants of wood dust and resin acid exposure during wood pellet production: measurement strategies and bias in assessing exposure-response relationships

Production of wood pellets is a relatively new and expanding industry in which the exposure profiles differ from those in other wood-processing industries like carpentries and sawmills where there are lower levels of wood dust. Sixty-eight personal exposure measurements of wood dust (inhalable and total dust) and resin acids were collected for 44 participants at four production plants located in Sweden. Results were used to estimate within- and between-worker variability and to identify uniformly exposed groups and determinants of exposure. In addition, overexposure, whether the risk of the long-term mean exposure of a randomly selected worker exceeding the occupational exposure limit is acceptably low, was calculated as well as the underestimation of the exposure-response relationship (attenuation). Greater variability in exposure between work shifts than between workers was observed with the within-worker variation accounting for 57-99% of the total variance in the individual-based model. Several uniformly exposed groups were detected but were mostly associated with a between-worker variation of zero which is an underestimation of the between-worker variation but an indication of uniformly exposed groups. Cleaning was identified as a work task that increases exposure slightly; so reducing workers' exposure during this operation is advisable. The levels of wood dust were high and were found to pose unacceptable risks of overexposure at all plants for inhalable dust and at three out of four plants for total dust. These findings show that exposure to dust needs to be reduced in this industry. For resin acids, the exposure was classed as acceptable at all plants. According to an individual-based model constructed from the data, the level of attenuation was high, and thus there would be substantial bias in derived dose-response relationships.     

有机磷农药生产工人心血管功能调查

分析了８７名有机磷接触工人的健康档案,发现接触甲胺磷、乐果、异稻瘟净的工人心电图异常发生率显著高于对照组（Ｐ≤０．０１）;后两组农药接触组心电图异常的检出率均显著高于接触前（Ｐ〈０．０５）。心电图改变具有多样性、可逆性特点;心电图的改变与胆碱酯酶的抑制无明显相关且不随工龄的增加而增高;提示乙酰胆碱的积聚不是有机磷所致心脏毒作用的主要原因。     

有机磷农药接触工人酯酶活力特征及基因多态对酶活力的影响

目的 研究接触有机磷农药对丁酰胆碱酯酶（BchE）、羧酸酯酶（CarbE）、对氧磷酶（PonE）和乙酰胆碱酯酶（AChE）活力的影响,并探讨酯酶基因多态性对长期接触有机磷农药工人酯酶活力的影响.方法 241名长期接触有机磷农药的生产工人为直接接触组,151名农药厂后勤人员为间接接触组,160名无有机磷农药接触的外厂工人为对照组.检测各组4种酯酶活力;用ABI 7900基因序列检测系统和基因芯片技术确定PON192、PON55和BchE基因型.结果对照组CarbE、BchE和PonE活力无年龄、性别差异.直接接触组、间接接触组的CarbE和BchE活力均明显低于对照组;直接接触组PonE活力明显低于对照组;直接接触组AChE活力明显低于间接接触组,差异均有统计学意义（P＜0.01）.直接接触组BchE基因型（UU、UK、KK）频率分别为74.3%、24.1%和1.6%;等位基因频率BCHE＊U=0.863、BCHE＊K=0.137.PON192基因型（AA,AB,BB）频率分别为15.0%、45.5%和39.5%;等位基因频率PON＊A=0.378、PON＊B=0.622.PON55基因型（MM、LM、LL）频率分别为96.2%、3.8%和0%;等位基因频率PON＊M=0.981、PON＊L=0.019.PON192和PON55不同基因型PonE活力差异有统计学意义（P＜0.01和P＜0.05）.结论 长期接触有机磷农药在不同程度上抑制4种酯酶的活力,PON192和PON55基因多态性影响有机磷接触工人PonE活力.     

Fifteen years of experience in cholinesterase monitoring of insecticide applicators

INTRODUCTION: Measuring cholinesterase(ChE) enzyme levels in red blood cells (RBC) and plasma has become a useful tool in the early detection of organophosphate and carbamate poisoning in insecticide handlers. Since 1974 the State of California has required testing of pesticide applicators to prevent disease. This study is a review of the testing experience of two physicians and using one laboratory so that a comparison can be made to previous studies by the author and others. METHODS: The files of 366 workers who were referred by their employers for ChE activity monitoring were abstracted for patient data, employer identification, and testing data. Results were entered into the EPIINFO program for analysis. RESULTS: A total of 366 workers from 45 companies were tested over a 15-year period between 1989 and 2004. Most were applicators. There were 690 attempts to establish baselines, of which 545 (79%) were successful. There were 519 monitoring tests on 228 workers, resulting in the removal from exposure of 18 employees, most in 1996. Self-reported exposure history and symptoms resulted in only 3 responses (.6%). The costs were significant ($47,160 total and $36 per test), especially when considering the failure of 145 (21%) employees to establish baselines. There was monthly and yearly variation in plasma and RBC baselines, monthly variance in plasma monitoring tests, and no monthly variance in RBC monitoring. The use of a third baseline test when the first two varied by 15% avoided two false positives. The mean time for recovery from ChE depression was 5.38 weeks. DISCUSSION: The California ChE monitoring program remains a valuable tool. There was significant monthly and yearly variation in values for both baseline and monitoring plasma and RBC values, with the exception of RBC monthly variance. Self-reported symptoms were not found to be a valuable tool in measuring exposure. Rates of recovery from ChE depression were highly variable. The warning feature of the program was very effective. The costs of monitoring were substantial, but possibly not as great as a single workers' compensation case. CONCLUSIONS: The California ChE monitoring program serves as a useful and cost-effective means of preventing organophosphate and carbamate overexposure. Elimination of the third baseline test requirement should be considered.     

Effects of chronic exposure to low doses of trichloroethylene on steroid hormone and insulin levels in normal men.

The aim of this study was to examine the serum levels of insulin and some adrenal steroid hormones in men chronically exposed to low doses of trichloroethylene (TCE). A total of 85 workers participated in this study. Each worker had urine collected and analyzed for trichloroacetic acids (UTCA) on the same day that a blood sample was taken for analyses of serum testosterone, sex hormone-binding globulin (SHBG), androstenedione, cortisol, aldosterone, and insulin. The mean concentration of environmental TCE was 29.6 ppm and the mean UTCA was 22.4 mg/g creatinine (range 0.8-136.4). TCE exposure did not cause any significant changes to the adrenal steroid hormone productions. The results showed that UTCA was significantly correlated to serum insulin levels. Insulin and SHBG responded in tandem, with the highest levels found in workers exposed to TCE for less than 2 years; levels of both parameters were significantly lowered in those exposed for more than 2 years. A triphasic response in insulin levels to TCE, which depended on the duration of exposure, was noted. Initial exposure caused an acute rise in insulin levels. This was followed by a fall to normal levels in those exposed 2-4 years and then a slight rise in those exposed for more than 6 years. The mechanism for this pattern of response to TCE exposure is yet unknown.     

Aniline in hydrolyzed urine and plasma--possible biomarkers for phenylisocyanate exposure

There are few studies on phenylisocyanate (PhI) exposure, although there are studies indicating that PhI is a very potent chemical sensitizer. The aim of this study was to evaluate aniline in urine and plasma as possible biomarkers of exposure to PhI. Occupational airborne exposure to PhI was measured during one day for 11 workers exposed to thermal degradation products from polyurethane with filters impregnated with 2-methoxyphenyl piperazine. A urine sample was collected from each worker on measurement day, and plasma samples were collected within the following 2 weeks. Urine and plasma samples also were collected from four unexposed subjects. The biological samples were hydrolyzed and analyzed with gas chromatography mass spectrometry. The time-weighted averages (TWA) for the workers were between 0.1 and 1.6 microg/m3. Aniline levels in urine were in the same range for the exposed and unexposed workers, but there was a significant correlation between air and urinary levels (Pearson's correlation coefficient r = 0.518; p = 0.05). All exposed workers had higher levels in the plasma samples than the highest control, and there was a significant correlation between the plasma levels and measured air levels (r = 0.675; p = 0.008). The conclusion is that aniline in hydrolyzed urine and plasma are possible biomarkers of exposure to PhI, and that the plasma biomarker is more sensitive, at least at this rather low exposure.     

Peripheral neurotoxicity in workers exposed to inorganic mercury compounds

Nerve conduction velocity (NCV) of the median motor, median sensory, and sural nerves was assessed in 16 workers chronically exposed to various inorganic mercury compounds. Exposed workers were compared with an unexposed control group using t test analyses. Slowing of the median motor nerve NCV was found, which was correlated with both increased levels of mercury in blood and urine, and with increased number of neurologic symptoms. Sensitive evaluation of neural function was found to be practical and informative for investigating mercury toxicity. Such evaluation can help determine safe mercury levels at the workplace.     

Upper reference limits for biomarkers of exposure to aromatic diisocyanates

Objectives: The objectives of this study were to determine the levels of 2,4-toluenediamine, 2,6-toluenediamine, 1,5-naphthtalenediamine and 4,4-methylenediphenyldianiline in hydrolyzed urine and plasma for occupationally unexposed workers and to calculate upper reference limits (URLs). These analytes are biomarkers of exposure to 2,4-toluene diisocyanate and 2,6-toluene diisocyanate (2,4-TDI and 2,6-TDI), 1,5-naphtalene diisocyanate (NDI) and 4,4-methylenediphenyl diisocyanate (MDI), respectively. Methods: The biomarker levels were determined in urinary and plasma samples obtained from 121 occupationally unexposed workers. Based on these biomarkers levels and the biomarker levels in an occupationally exposed group of workers, URLs were calculated. The method used for these calculations was based on the receiver operator characteristic (ROC) curve method technique, and the URLs were set at the optimum of sum of sensitivity and specificity. Results: The URLs for the different diisocyanates were calculated to be in the range of 0.1–0.5 g/L. Occupationally unexposed workers had detectable biomarker levels of the diisocyanates investigated. Especially abundant was the biomarkers of MDI which were found in 97% of both urinary and plasma samples. For the other biomarkers, 0–15% of the unexposed workers had detectable levels. The detected levels were mostly close to the limit of detection (LOD), but urinary levels of biomarkers of MDI up to 60 times the LOD were found. The sensitivities and specificities for classification of the workers as occupationally exposed or not, were in the range of 88–100% and 97–100%, respectively. Conclusions: The URLs were calculated that may be applicable when screening for occupational exposure. A worker with a biomarker level above the URL will be classified as occupationally exposed. Biomarkers of aromatic diisocyanates, especially biomarkers of MDI, were present among occupationally unexposed workers, but the source and nature of the exposure is unknown.     

Symptoms and cholinesterase activity among rural residents living near cotton fields in Nicaragua.

OBJECTIVES: To explore whether symptoms resulted from pesticide spray drift on residentially exposed populations in rural Nicaragua. METHODS: 100 residents, each 10 years of age or older, were randomly selected from a Nicaraguan community surrounded by actively sprayed cotton fields (the exposed community) and from a socioeconomically similar community far from agricultural spraying (the control community). Subjects working with pesticides were excluded, and the study was conducted at the end of the 1990 cotton spraying season (August-December). Demographic information, exposure questions, and prevalence of 11 acute symptoms and 17 chronic symptoms were gathered from a structured interview. Finger stick erythrocyte cholinesterase (AChE) was measured with a portable colorimeter. Acute symptoms were grouped according to their previously known associations with cholinesterase (ChE) inhibitors into four ordinal categories (asymptomatic, non-specific, possible, probable). RESULTS: Residents from the exposed community were significantly more likely to report recently sighting a spray plane near their community, exposure to pesticide from drift, crossing recently sprayed fields, eating home grown food, and feeling ill after drift exposure. The mean AChE value was significantly lower for residents of the exposed community (4.9 v 5.3 IU/dl). The proportion of subjects complaining of one or more chronic or acute symptoms was significantly higher for the exposed community (87%) than for the controls (53%). Odds ratios for residents in the exposed community, by symptom categories, were non-specific 1.6 (95% confidence interval (95% CI) 0-8 to 3.2), possible 4.1 (95% CI 1.7 to 10.2), and probable 9.93 (95% CI 2-9 to 34.4). CONCLUSION: These findings indicate a strong association between exposure to aerial pesticides and symptoms. This study should be replicated with more quantitative exposure measures, for if confirmed, the results have relevance for millions in rural communities worldwide.     

Fifteen Years of Experience in Cholinesterase Monitoring of Insecticide Applicators

Abstract

Introduction: Measuring cholinesterase (ChE) enzyme levels in red blood cells (RBC) and plasma has become a useful tool in the early detection of organophosphate and carbamate poisoning in insecticide handlers. Since 1974 the State of California has required testing of pesticide applicators to prevent disease. This study is a review of the testing experience of two physicians and using one laboratory so that a comparison can be made to previous studies by the author and others.

Methods: The files of 366 workers who were referred by their employers for ChE activity monitoring were abstracted for patient data, employer identification, and testing data. Results were entered into the EPIINFO program for analysis.

Results: A total of 366 workers from 45 companies were tested over a 15-year period between 1989 and 2004. Most were applicators. There were 690 attempts to establish baselines, of which 545 (79%) were successful. There were 519 monitoring tests on 228 workers, resulting in the removal from exposure of 18 employees, most in 1996. Self-reported exposure history and symptoms resulted in only 3 responses (.6%). The costs were significant ($47,160 total and $36 per test), especially when considering the failure of 145 (21%) employees to establish baselines. There was monthly and yearly variation in plasma and RBC baselines, monthly variance in plasma monitoring tests, and no monthly variance in RBC monitoring. The use of a third baseline test when the first two varied by 15% avoided two false positives. The mean time for recovery from ChE depression was 5.38 weeks.

Discussion: The California ChE monitoring program remains a valuable tool. There was significant monthly and yearly variation in values for both baseline and monitoring plasma and RBC values, with the exception of RBC monthly variance. Self-reported symptoms were not found to be a valuable tool in measuring exposure. Rates of recovery from ChE depression were highly variable. The warning feature of the program was very effective. The costs of monitoring were substantial, but possibly not as great as a single workers' compensation case.

Conclusions: The California ChE monitoring program serves as a useful and cost-effective means of preventing organophosphate and carbamate overexposure. Elimination of the third baseline test requirement should be considered.     

Variation in plasma cholinesterase activity among greenhouse workers, fruitgrowers, and slaughtermen

The purpose of the study was to compare the plasma cholinesterase (ChE) activities of 100 greenhouse workers and 43 fruitgrowers engaged in spraying insecticides with those of 113 slaughtermen who served as controls. The ChE activity in the greenhouse workers and fruitgrowers was not significantly lower than in the controls. Nevertheless the ChE activity of greenhouse workers declined with increasing exposure. The wearing of protective gloves appears to be of particular value for the safety of workers.     

The influence of personal protection, environmental hygiene and exposure to pesticides on the health of immigrant farm workers in a desert country

Farm workers in developing countries tend not to use protective measures while handling pesticides. This study investigates the use of personal protection equipment and the practice of safety and hygiene procedures in the handling of pesticides in agriculture. Methods: Through a multi-stage sampling technique, one-fifth of the farms in a region were selected and all the farm workers at these farms were included in the study. A comparison population matching in age, socio-economic status and stay in the region was selected. A specifically designed questionnaire was used to collect information on the use of protective measures and the practice of safety and hygiene during work and on the disposal of empty pesticide containers. Blood pressure and erythrocyte acetylcholinesterase (AChE) activity were measured in the exposed and the unexposed populations. Results: Protective equipment was worn by a minority of farm workers – gloves, by 35%; work coveralls, by 36%; a scarf to cover the nose and mouth, by 39%; and shoes at work, by 79%. With regard to personal hygiene measures, 83% of the workers changed clothes after work and the same proportion took a shower after work; 63% and 46% drank and ate while at work respectively; and 11% used articles of domestic use in the preparation of pesticides on the farm. Most of the farm workers (96%) were asked to prepare pesticides for spraying by the foreman and 61% were asked to spray the pesticides on the crops. AChE activity was highly significantly depleted in the exposed population as compared with the unexposed population. Conclusions: AChE depletion was found to be negatively associated with the use of gloves, of work coveralls, and of a scarf to cover the nose and mouth and with the implementation of safety and hygiene procedures on the farm. AChE depletion was positively associated with the frequency of pesticide spraying. Received: 30 January 1998 / Accepted: 19 August 1998     

Variation in plasma cholinesterase activity among greenhouse workers, fruitgrowers, and slaughtermen.

The purpose of the study was to compare the plasma cholinesterase (ChE) activities of 100 greenhouse workers and 43 fruitgrowers engaged in spraying insecticides with those of 113 slaughtermen who served as controls. The ChE activity in the greenhouse workers and fruitgrowers was not significantly lower than in the controls. Nevertheless the ChE activity of greenhouse workers declined with increasing exposure. The wearing of protective gloves appears to be of particular value for the safety of workers.     

Exposure to peat dust: acute effects on lung function and content of bronchoalveolar lavage fluid.

Mechanised production of peat for fuel consumption is associated with high concentrations of organic dust, which is inhaled by the peat workers. In the present study 17 workers at two peat bogs in northern Sweden were examined. Personal sampling of total dust and the respirable fraction was performed during several workshifts. Dynamic spirometry was carried out before and at the end of shifts. Bronchoscopy with bronchoalveolar lavage (BAL) was performed in six subjects at the end of the working season and the results were compared with unexposed reference subjects. Peat workers using modern machines with ventilated cabins containing air filters were found to be exposed to low concentrations of peat dust. The recorded dust concentrations were below the threshold limit value for organic dust (5 mg/m3 air) in all but one worker. The respirable fraction of peat dust recorded in the breathing zone of the workers correlated significantly with a decrease in forced expiratory volume in one second (FEV1). The effect on lung function in non-asthmatic peat workers was, however, small. The concentration of lysozyme positive alveolar macrophages in BAL fluid was significantly lower in the peat workers compared with reference subjects. An inverse correlation was found between the mentioned cells and exposure to the respirable fraction of the peat dust. Furthermore, one particularly dust exposed worker had pronounced increases in alveolar macrophages, fibronectin concentration, and mast cells in BAL fluid.     

Exposure to peat dust: acute effects on lung function and content of bronchoalveolar lavage fluid

Mechanised production of peat for fuel consumption is associated with high concentrations of organic dust, which is inhaled by the peat workers. In the present study 17 workers at two peat bogs in northern Sweden were examined. Personal sampling of total dust and the respirable fraction was performed during several workshifts. Dynamic spirometry was carried out before and at the end of shifts. Bronchoscopy with bronchoalveolar lavage (BAL) was performed in six subjects at the end of the working season and the results were compared with unexposed reference subjects. Peat workers using modern machines with ventilated cabins containing air filters were found to be exposed to low concentrations of peat dust. The recorded dust concentrations were below the threshold limit value for organic dust (5 mg/m3 air) in all but one worker. The respirable fraction of peat dust recorded in the breathing zone of the workers correlated significantly with a decrease in forced expiratory volume in one second (FEV1). The effect on lung function in non-asthmatic peat workers was, however, small. The concentration of lysozyme positive alveolar macrophages in BAL fluid was significantly lower in the peat workers compared with reference subjects. An inverse correlation was found between the mentioned cells and exposure to the respirable fraction of the peat dust. Furthermore, one particularly dust exposed worker had pronounced increases in alveolar macrophages, fibronectin concentration, and mast cells in BAL fluid.     

Assessment of Genotoxic Damage in Lymphocytes of Hospital Workers Exposed to Ionizing Radiation in Argentina

The authors aimed to assess genotoxic damage in the lymphocytes of workers chronically exposed to ionizing radiation. The studied population included 15 exposed donors of the radiology unit of a public hospital in La Plata, Argentina. The control group included 15 nonexposed employers from administrative areas that the authors matched by age, sex, and smoking habits. The mean frequency of cytogenetic damage was higher in the exposed group than in the unexposed group for aneuploidy and structural chromosome aberrations. They observed the highest difference when achromatic lesions (or gaps) were considered. The comet assay showed that the frequency of cells with low damage was higher in the exposed group than in the unexposed group. A mean length analysis showed significant differences between exposed and nonexposed people. The results can be considered to be consistent evidence of occupational radiation exposure, and the results indicate that the workers must be advised to avoid or minimize their exposure.