Dry-cleaning Workers Research Articles

Oxidative stress and pro-inflammatory cytokines following perchloroethylene exposure in young female dry-cleaning workers.

The involvement of Perchloroethylene (PCE) in the development of autoimmune diseases has been reported. However, few studies investigated immunotoxicity in PCE-exposed workers. To study changes in the oxidative stress and cytokine profile of young female dry-cleaning workers exposed to PCE. Thirty-eight exposed workers and 38 unexposed controls were recruited. All the participants were young nonsmoker females. Individual interviews were conducted by a physician. Blood samples were collected and hematological tests were performed by an automated Coulter Counter. Plasma PCE levels were determined using gas chromatography/flame ionization detection. Plasma total antioxidant capacity (TAC), Catalase (CAT), Superoxide dismutase (SOD), and Malondialdehyde (MDA) levels were measured using the colorimetric method. The levels of plasma cytokines interleukin-1β (IL-1β), IL-2, IL-4, IL-6, IL-8, tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) were measured by commercially kits. The levels of plasma PCE averaged 561±96 ng/ml in the exposed group compared with 1.3±0.5 ng/ml in the controls. The hematological tests failed to find abnormalities in the exposed workers. Exposed workers presented significantly increased plasma levels of MDA, SOD and CAT. There were no significant differences between the two groups for level of plasma TAC. Significantly increased plasma IL-1β and TNF-α and decreased IL-2 and IL-8 levels were seen in the exposed workers. There were no significant differences between the two groups for IL-4, IL-6, and IFN-γ. PCE exposure resulted in changed cytokine profile in dry-cleaning workers, suggesting the potential immunotoxicity of PCE at low exposure levels.

Health Hazards, Hematological and Biochemical Alterations in Dry-Cleaning Workers using Perchloroethylene.

Perchloroethylene (PERC) is commonly used as a dry-cleaning solvent, it is attributed to many deleterious effects in the biological system. The study aimed to investigate the harmful effect associated with PERC exposure among dry-cleaning workers. The study was carried out on 58 adults in two groups. PERC-exposed group; include thirty-two male dry-cleaning workers using PERC as a dry-cleaning solvent and twenty-six healthy non-exposed subjects. History of PERC exposure, use of personal protection equipment (PPE), safety measurement of the exposed group was recorded. Blood sample was taken from each participant for measurement of hematological markers, liver and kidney function tests. The results showed that 28.1% of the workers were using PPE regularly while 71.9% of the workers were not. Most of the workers 31(96.9%) were disposed of their waste products in improper way. Non-significant differences were observed in hematological indices between PERC-exposed group and non-exposed group. Serum level of kidney and liver function markers of the dry-cleaning workers were higher with statistically significant difference compared with the non-exposed group. In conclusion, a non-significant alteration in hematological parameters, while significant changes in part of liver and kidney functions indices have been demonstrated. Clinical observation indicated a harmful effect in PERC-exposed group.
 Key words: Occupational, PERC, personal protective equipment, dry cleaner

Literature Review: Biological Monitoring of Occupational Tetrachloroethylene Exposure in Workers

Introduction: One of the most common chlorinated solvents in the world is tetrachloroethylene (TCE) because it is widely used in various industries. Exposure to tetrachloroethylene can cause health problems so biological monitoring is necessary to do. The aim of this research is to assess which one is more feasible to use among the various types of biological monitoring for tetrachloroethylene exposure, based on the evidence-based literature. Methods: The literature searching was performed via electronic databases from PubMed, Scopus, and Proquest. The keywords used were “biological monitoring”, “biomonitoring”, “tetrachloroethylene”, “perchloroethylene”, “work” and “occupation”. The articles were chosen based on the given inclusion and exclusion criteria. Selected articles were then critically appraised. Results: Initially 29 papers were collected, but only6 cross-sectional articles were selected after the screening process and manual searching. Based on the selected evidence-based literatures, statistically meaningful associations were found between tetrachloroethylene exposure and tetrachloroethylene in blood in pre- and end-of-shift, in urine at end of shift, and in exhaled air at end-of-shift. Moreover, micronucleus frequency and DNA damages between dry cleaning workers and the controls differed significantly. Conclusion: The level of tetrachloroethylene in blood, urine, and exhaled air becomes an appropriate biological exposure index for assessing tetrachloroethylene exposure in dry-cleaning workers. In Indonesia, biomonitoring that is more feasible to be implemented is micronucleus frequency evaluation from buccal mucosal epithelial smears since it is a simpler, faster, and less expensive procedure.Keywords: biological monitoring, biomonitoring, occupational exposure, tetrachloroethylene

Preliminary Study: Environmental Assessment of Perchloroethylene in Dry-Cleaning Facilities in the UAE.

Background Perchloroethylene (PERC) is a widely spread cleaning solvent, used in nearly all dry-cleaning facilities. It has been declared as “probable human carcinogen” by the International Agency for Research on Cancer (IARC) due to its hazardous and toxic effects on human health. The study aimed at assessing the exposure of PERC among dry-cleaning workers at four different dry-cleaning facilities in the UAE. Methods The four dry-cleaning facilities, using PERC in one of the cities of the UAE, were selected. Draeger perchloroethylene 10/b detector tubes along with a Draeger accuro pump were used to estimate the levels of PERC exposure in three main selected positions in each of the facilities. Results The results showed that the second selected position had the highest amounts of PERC exposure above the international and local standards in 3 out of 4 selected facilities. The workers at position 2, who were not using any of the provided personal protective equipment, were at the highest risk of developing PERC-related health problems. Conclusion It is important to install local exhaust ventilation systems and monitoring devices of PERC concentrations in these facilities, along with raising the awareness of workers about the health effects of PERC and the importance of using personal protective equipment (PPE) while performing their job.

Trace analysis in end-exhaled air using direct solvent extraction in gas sampling tubes: tetrachloroethene in workers as an example.

Simple and cost-effective analytical methods are required to overcome the barriers preventing the use of exhaled air in routine occupational biological monitoring. Against this background, a new method is proposed that simplifies the automation and calibration of the analytical measurements. End-exhaled air is sampled using valveless gas sampling tubes made of glass. Gaseous analytes are transferred to a liquid phase using a microscale solvent extraction performed directly inside the gas sampling tubes. The liquid extracts are analysed using a gas chromatograph equipped, as usual, with a liquid autosampler, and liquid standards are used for calibration. For demonstration purposes, the method's concept was applied to the determination of tetrachloroethene in end-exhaled air, which is a biomarker for occupational tetrachloroethene exposure. The method's performance was investigated in the concentration range 2 to 20 μg tetrachloroethene/L, which corresponds to today's exposure levels. The calibration curve was linear, and the intra-assay repeatability and recovery rate were sufficient. Analysis of real samples from dry-cleaning workers occupationally exposed to tetrachloroethene and from nonexposed subjects demonstrated the method's utility. In the case of tetrachloroethene, the method can be deployed quickly, requires no previous experiences in gas analysis, provides sufficient analytical reliability, and addresses typical end-exhaled air concentrations from exposed workers.

Biomonitoring Study of Dry Cleaning Workers Using Cytogenetic Tests and the Comet Assay

Perchloroethylene (PCE) is the main solvent used in the dry cleaning industry worldwide. The aim of the present work was to evaluate the genotoxic potential of occupational exposure to PCE in dry cleaning workers. The study was carried out in 59 volunteers (30 workers, 29 controls). The genotoxic effect was evaluated by analyzing chromosome aberrations (CAs), and micronuclei (MN) and DNA damage (assessed by the comet assay) in peripheral blood lymphocytes. Environmental monitoring of exposure was carried out on personal breathing zone air samples collected during two consecutive working days by measuring the concentration of PCE air levels. The mean PCE concentration in workplace air of dry cleaning workers was 31.40 mg/m3. There were no significant differences in CA frequency between dry cleaning workers and the controls, but analysis showed a significant association of CA frequency with employment duration and frequency of exposure to PCE. The MN frequency and DNA damage detected by alkaline comet assay were significantly increased in dry cleaning workers compared to the controls. The results suggest that (a) chronic occupational exposure to dry cleaning solvents below permissible occupational exposure limit of 70 mg/m3 (i.e., ∼10.3 ppm) may lead to an increased risk of genetic damage among dry cleaning workers, and (b) CA, MN tests, and comet assay are useful to monitor populations exposed to low doses of PCE.

Simultaneous determination of trichloroethylene, perchloroethylene and trichloroacetic acid in human urine using solid-phase microextraction fibre coated with single-walled carbon nanotubes

A reliable and sensitive method for simultaneous determination of perchloroethylene (PCE), trichloroethylene (TCE), and trichloroacetic acid (TCA) in human urine by gas chromatography-mass spectrometry (GC/MS) is described after extraction and preconcentration by a new solid-phase microextraction (SPME) adsorbent. The potential of single-walled carbon nanotubes (SWCNTs) as SPME adsorbent for the pre-concentration of environmental pollutants has been investigated in recent years. This work was carried out to investigate the feasibility of SWCNTs as a headspace SPME adsorbent for the determination of chloroethylenes in human urine. SWCNTs were attached onto a stainless steel wire through an organic binder. Potential factors affecting the extraction efficiency, including extraction time, extraction temperature, desorption time, desorption temperature, and salinity were optimized. The developed method showed good performance. For PCE and TCE, calibration curves were linear (r 2 ≥ 0.994) over the concentration ranges from 15 to 8000 ng L−1 and the limit of detection (LOD) at signal-to-noise (S/N) ratio of 3 was 5 ng L−1. The analytical procedure also involves derivatization of TCA with dimethyl sulfate, before headspace sampling. For TCA the linear range and LOD were 45-8000 (r 2 ≥ 0.992) and 15 ng L−1, respectively. In addition, a comparative study between the SWCNT and a commercial carboxen/polydimethylsiloxane (CAR/PDMS) SPME fibre for the determination of chloroethylenes in human urine was carried out. SWCNT fibre showed higher extraction capacity, better thermal stability (over 350°C) and longer life span (over 200 times) than the commercial CAR/PDMS fibre. The developed method was successfully applied to determine chloroethylenes in human urine samples. As the results indicated, the mean concentrations of TCE, PCE and TCA in exposed workers (dry-cleaning industry workers) were significantly greater than that of control group.

Exposure Assessment to Trichloroethylene and Perchloroethylene for Workers in the Dry Cleaning Industry

Perchloroethylene and trichloroethylene are two particular organochloro compounds, are often used for dry-cleaning. In the present study the excretion of urinary Perchloroethylene and trichloroethylene were evaluated as biomarkers of exposure to these compounds. The mean value of Perchloroethylene in breathing zone and the total Perchloroethylene uptake during the work shift of the three groups of dry-cleaning workers according to the capacity of the dry-cleaning machine (8, 12 and 18kg) were 31.04, 50.87 and 120.99mgm(-3) and 11.46, 22.6 and 41.6μgL(-1), respectively, which were significantly greater than the occupationally nonexposed groups. A good correlation (r=0.907) between the mean values of Perchloroethylene in breathing zone and the urinary concentrations was observed.

Immunotoxicity and hematotoxicity induced by tetrachloroethylene in egyptian dry cleaning workers

The immune and hematological systems can be a target for environmental contaminants with potential adverse effects, so the purpose of this study is to provide documentation on immunotoxicity and hematotoxicity of tetrachloroethylene, which is widely used in dry cleaning in Egypt. This study was carried out on 80 adult males. Subjects designated as controls (n = 40) were healthy persons and others were tetrachloroethylene-exposed dry-cleaning workers (n = 40). The controls and tetrachloroethylene-exposed workers were then divided into four equal groups (20 individuals/group): group I, control group never smoking; group II, smoking control group; and groups III and IV, tetrachloroethylene-exposed nonsmoking and smoking workers, respectively. Blood level of tetrachloroethylene, complete blood count, immunoglobulins (IgA, IgM, IgG, and IgE), the total numbers of white blood cells (WBC), and leukocyte differential counts, as well as interferon γ (IFN-γ) and interleukin-4 (IL-4), were measured. The immunotoxicity of tetrachloroethylene appeared in the form of an increase in serum immunoglobulin E in nonsmoking and smoking tetrachloroethylene-exposed workers, while the serum immunoglobulins A, M, and G levels showed no significant change in all studied groups. In addition, our results demonstrated a significant increase in white cell count, lymphocytes, natural killer (NK; CD3+CD16CD56+) cells, and B (CD19+) lymphocytes. The increase in WBC and lymphocytes may be attributed to allergic reaction. Moreover, serum and lymphocytic interlukin-4 levels were significantly increased in nonsmoking and smoking tetrachloroethylene-exposed workers. Tetrachloroethylene exposure is associated with immunotoxicity, which may lead to the augmentation of allergic diseases or appearance of autoimmune reaction.

Bayesian Analysis of a Physiologically Based Pharmacokinetic Model for Perchloroethylene in Humans

Perchloroethylene (PCE) is a widely distributed pollutant in the environment, and is the primary chemical used in dry cleaning. PCE-induced liver cancer was observed in mice, and central nervous system (CNS) effects were reported in dry-cleaning workers. To support reconstruction of human PCE exposures, including the potential for CNS effects, an existing physiologically based pharmacokinetic (PBPK) model for PCE in the human (Covington et al., 2007) was modified by adding a brain compartment. A Bayesian approach, using Markov chain Monte Carlo (MCMC) analysis, was employed to re-estimate the parameters in the modified model by combining information from prior distributions for the model parameters and experimental data. Experimental data were obtained from five different human pharmacokinetic studies of PCE inhalation exposures ranging from 150 ppm to as low as 0.495 ppm. The data include alveolar or exhaled breath concentrations of PCE, blood concentrations of PCE and trichloroacetic acid (TCA), and urinary excretion of TCA. The PBPK model was used to predict target tissue dosimetry of PCE and its key metabolite, TCA, during and after the inhalation exposures. Posterior analysis was performed to see whether convergence criteria for each parameter were satisfied and whether the model with posterior distributions may be used to make accurate predictions of human kinetic data. With posteriors, the trend of percent of PCE metabolized in the liver at low concentrations was predicted under different exposure conditions. The 95th percentile for the fraction PCE metabolized at a concentration of 1 ppb was estimated to be 1.89%.

Occupational Exposure to Perchloroethylene in Dry-cleaning Shops in Tehran, Iran

Perchloroethylene, the most widely used solvent in dry cleaning, is toxic to the liver, kidneys and central nervous system and may be a human carcinogen. An exposure assessment was carried out in 69 dry-cleaning shops using perchloroethylene in Tehran city, Iran. The 8-h time weighted average (TWA) breathing zone air samples and end-exhaled air samples were obtained from 179 workers who worked as the job titles included machine operator (n=71), presser (n=63) and counter area (clerk) (n=45). The mean perchloroethylene concentrations in breathing zone air were 11.5 ppm, 9.6 ppm and 7.2 ppm respectively. The mean perchloroethylene concentrations in end-exhaled air of the same participants in Saturday morning (prior to shift of workweek) were 1.7 ppm, 1.5 ppm and 1.1 ppm, but in Thursday evening (end of shift at end of workweek) were 2.4 ppm, 2.0 ppm and 1.5 ppm respectively. This study found that, the mean perchloroethylene concentrations in breathing zone air and end-exhaled air in the dry-cleaning workers were lower than the TLV (25 ppm) and BEI (5 ppm) recommended by ACGIH. Regression analysis showed that the concentration of perchloroethylene in breathing zone air (TWA) was highly and significantly correlated with the concentration of perchloroethylene in end-exhaled air in Saturday morning with a regression equation Y=0.147X + 0.031 (r=0.99, p<0.001) and also in Thursday evening with a regression equation Y=0.201X + 0.072 (r=0.98, p<0.001) where X is the concentration of perchloroethylene in breathing zone air and Y is that the concentration of perchloroethylene in end-exhaled air. The results also showed the potential utility of measuring the concentration of perchloroethylene in end-exhaled air as a method for assessing relative exposure in dry cleaning shops which use it.

Pressed for Hard Facts: Multiple Tetrachloroethylene–Cancer Links Go Unconfirmed

Vol. 114, No. 2 EnvironewsOpen AccessPressed for Hard Facts: Multiple Tetrachloroethylene–Cancer Links Go Unconfirmedis accompanied byCancer in Persons Working in Dry Cleaning in the Nordic Countries Harvey Black Harvey Black Search for more papers by this author Published:1 February 2006https://doi.org/10.1289/ehp.114-a114AboutSectionsPDF ToolsDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InReddit Recent U.S. studies have linked dry cleaners’ exposure to tetra-chloroethylene, a solvent used in the industry, to an increased risk for a number of cancers, including esophageal, lung, and cervical cancer. Results of other studies on bladder and pancreatic cancer are equivocal. Still other studies have shown an increased risk of non-Hodgkin lymphoma. Now a study by a team of Nordic researchers of cancer risk among dry-cleaning workers in Denmark, Finland, Norway, and Sweden finds that, with the exception of bladder cancer, exposure to the solvent showed no link to the disease [EHP 114:213–219].The researchers identified 46,768 dry-cleaning and laundry workers from the 1970 censuses in the four countries. The investigation was a series of case–control studies nested within this cohort of workers. Controls were matched by country, sex, and five-year group for age and year of cancer diagnosis.The team studied the period from 1964 to 1979, when tetrachloroethylene was the primary solvent used for dry cleaning in these countries. The team considered four categories of exposure: exposed workers in dry-cleaning shops with fewer than ten workers (reflecting a probability of sharing tasks and working in more cramped quarters), other workers in dry-cleaning shops (such as seamstresses and office workers), unexposed laundry workers and others not working in a dry-cleaning shop, and those who could not be classified.Blinded telephone interviews were done with cases, controls, and, eventually, next of kin in Norway and Sweden. If the subject’s occupation was dry cleaning, the interview covered length of employment in the dry-cleaning shop, number of workers in the shop, solvents used, and the subject’s smoking and drinking habits. For Denmark and Finland, pension records and other data sources were used to gather comparable information.Although exposure to tetrachloroethylene varied greatly among shops, the average annual level of exposure was fairly stable between 1964 and 1979. The team found no increase in risk of cancers of the esophagus, gastric cardia, liver, pancreas, or kidney. There was also no link to non-Hodgkin lymphoma. The study did, however, find a 44% excess risk in bladder cancer concentrated in Norway and Denmark, the two countries with the best data.The authors point to several strengths of the study, particularly its completeness. It covered all persons working in dry cleaning in 1970 in the Nordic countries. It also compared two cohorts, dry-cleaning workers and laundry workers, who had similar jobs except for the exposure to tetrachloroethylene.The authors also acknowledge the study had some weaknesses. For a high proportion of cases and controls from Sweden and Finland the authors could not determine whether the subjects worked in either a laundry or dry-cleaning business. Consequently, estimates of cancer risk were reported for all four countries together and for Denmark and Norway together. Furthermore, subjects could not be classified by exposure level to tetrachloroethylene. The researchers note, though, that because the data indicated a fairly stable level of exposure during employment, they consider length of time on the job an adequate surrogate measure of a cumulative dose.Clean sweep for dry cleaners?Tetrachloroethylene, a solvent widely used in the dry-cleaning industry, has been implicated in many cancers, but a new study of Nordic dry cleaners fails to corroborate most of those links.FiguresReferencesRelatedDetailsRelated articlesCancer in Persons Working in Dry Cleaning in the Nordic Countries13 October 2005Environmental Health Perspectives Vol. 114, No. 2 February 2006Metrics About Article Metrics Publication History Originally published1 February 2006Published in print1 February 2006 Financial disclosuresPDF download License information EHP is an open-access journal published with support from the National Institute of Environmental Health Sciences, National Institutes of Health. All content is public domain unless otherwise noted. Note to readers with disabilities EHP strives to ensure that all journal content is accessible to all readers. However, some figures and Supplemental Material published in EHP articles may not conform to 508 standards due to the complexity of the information being presented. If you need assistance accessing journal content, please contact [email protected]. Our staff will work with you to assess and meet your accessibility needs within 3 working days.

Cancer in Persons Working in Dry Cleaning in the Nordic Countries

U.S. studies have reported an increased risk of esophageal and some other cancers in dry cleaners exposed to tetrachloroethylene. We investigated whether the U.S. findings could be reproduced in the Nordic countries using a series of case–control studies nested in cohorts of laundry and dry-cleaning workers identified from the 1970 censuses in Denmark, Norway, Sweden, and Finland. Dry-cleaning work in the Nordic countries during the period when tetrachloroethylene was the dominant solvent was not associated with an increased risk of esophageal cancer [rate ratio (RR) = 0.76; 95% confidence interval (CI), 0.34–1.69], but our study was hampered by some unclassifiable cases. The risks of cancer of the gastric cardia, liver, pancreas, and kidney and non-Hodgkin lymphoma were not significantly increased. Assistants in dry-cleaning shops had a borderline significant excess risk of cervical cancer not found in women directly involved in dry cleaning. We found an excess risk of bladder cancer (RR = 1.44; 95% CI, 1.07–1.93) not associated with length of employment. The finding of no excess risk of esophageal cancer in Nordic dry cleaners differs from U.S. findings. Chance, differences in level of exposure to tetrachloroethylene, and confounding may explain the findings. The overall evidence on bladder cancer in dry cleaners is equivocal.

Mortality in dry-cleaning workers: an update.

A cohort of 1,708 dry-cleaning workers identified from union records was exposed to perchloroethylene (PCE), a known animal carcinogen and probable human carcinogen, for at least 1 year before 1960. Many workers also had exposure to Stoddard solvent, a petroleum-based dry-cleaning solvent. Vital status was updated through 1996 and life table analyses conducted. The cohort had excess cancer mortality (271 deaths, standardized mortality ratio [SMR] 1.25, 95% confidence interval [CI] 1.11-1.41). Elevated SMRs for tongue, bladder, esophagus, intestine, lung, and cervical cancer, pneumonia, and diseases of the stomach and duodenum were statistically significant. The current study confirms findings of prior updates and other studies that dry-cleaning workers have excess cancer mortality at several sites. Although important lifestyle and socioeconomic risk factors exist for both cervical and esophageal cancer mortality, excesses of these sites in the PCE only subcohort and among workers with longer duration of PCE exposure suggest an association with PCE exposure.

Kidney and liver biomarkers in female dry-cleaning workers exposed to perchloroethylene

Blood and urine perchloroethylene and urine trichloroacetic acid, as markers of exposure, and serum AST, ALT, GGT and creatinine, urine total solutes and proteins, angiotensin converting enzyme, N-acetyl-ß-D-glucosaminidase and glutamine synthetase, as markers of effect, were measured in 40 dry-cleaning and 45 ironing-shop female workers. Average perchloroethylene air level in the dry-cleaning shops was 59.7 mg m-3, i.e. three-fold lower than the current A.C.G.I.H. TLV-TWA (170 mg m-3). No statistically significant difference in the mean values of any of the effect markers was observed between the two groups, except for AST which was significantly higher in drycleaners. In addition, a statistically significant correlation was observed in dry-cleaners between environmental perchloroethylene and total urinary solutes (r = 0.308, p < 0.05) or urine glutamine synthetase (r= 0.469, p < 0 .01), between glutamine synthetase and blood perchloroethylene in post-shift (r= 0.406, p < 0.01) or urinary perchloroethylene in post(r= 0.571, p < 0.001) or pre-shift (r= 0.586, p < 0.001), and between urinary perchloroethylene in pre-shift and GGT (r= 0.407, p < 0.05). Interestingly, some statistically significant correlations between exposure and effect indices were found in ironing-shop workers alone, as in all subjects. Finally, transaminases, GGT and total urinary proteins were influenced by age and alcohol consumption which were significantly higher in dry-cleaners, thus providing an explanation for some of the correlations observed. In conclusion, our results show a dose-related increase of glutamine synthetase activity,a marker of damage of the pars recta of the kidney proximal tubule, in the urine of female subjects exposed to perchloroethylene concentrations in the work environment lower than current A.C.G.I.H. TLV-TWA.

Perchloroethylene-induced nephrotoxicity in dry-cleaning workers: is there a role for free radicals?

A recent study demonstrates that dry-cleaners chronic- significant increase in a number of parameters (urinary ally exposed to perchloroethylene (PCE) show clear excretion of proteins, laminin fragments, glycosaminoevidence for renal damage [1]. PCE is a synthetic glycan, and tubular epithelial brush-border antigen) halogenated hydrocarbon. It is used extensively for indicative of PCE-induced early renal damage. The dry cleaning fabrics and for metal-degreasing opera- authors concluded that long-term monitoring is tions. PCE enters the environment when it is released required in PCE-exposed individuals for the possible to the air during handling or into the surface water development of chronic renal disease. during waste disposal. PCE has been found in at least half of the waste sites identified as hazardous by the US Environmental Protection Agency [2]. It is estim- Animal studies ated that more than 650 000 US workers may be exposed to PCE. A number of human and animal Rats exposed to 470 p.p.m. for 150 days showed studies suggest that PCE might induce a variety of increase in kidney weight and evidence for tubular cell toxic biological eVects. To prevent the toxic eVects of injury in the form of cell swelling and shedding [6 ]. PCE on workers, the US Occupational Safety and The tubular cell shedding in this animal model may be Health Administration has set limit on the amount of the severe form of what Mutti et al. [1] reported in exposure, which is 100 p.p.m. for an 8-h workday over human, i.e., ‘shedding of tubular epithelial membrane a 40-h workweek [2]. This article will review some of components’. Hayes et al. [7] examined the toxicity of the studies pertaining to the toxic eVects of PCE on PCE in the rats by administering it in their drinking the kidney and examine the evidence for a role for free water. PCE-contamination of the surface water occurs radicals in the pathogenesis of such injury. and contaminated drinking water can be a source for PCE exposure. Rats exposed to 400 and 1400 mg PCE per kg, but not 14 mg per kg, showed evidence for

Primary liver cancer and renal cell carcinoma in laundry and dry-cleaning workers in Denmark.

Previous studies have shown an excess risk of primary liver cancer among women working in laundries and dry-cleaning shops in Denmark at the time of the census in 1970. During the period 1970-1987, 14 cases of primary liver cancer were observed (standardized mortality ratio 2.7, 95% confidence interval 1.5-4.5). A nested case-referent study was undertaken in order to classify laundry workers and dry-cleaning workers separately. According to hints in the literature, renal-cell carcinomas were also included in this analysis. Original census forms from 1970 were retrieved from the Danish National Record Office for the 17 cases with primary liver cancer and the 16 cases with renal-cell carcinoma and five matched referents per case. All of the 17 patients with primary liver cancer worked in laundries in 1970, whereas only 74% of the referents worked in laundries. Neither was the risk of renal-cell carcinoma associated with dry-cleaning work (relative risk 0.7, 95% CI 0.2-2.6). The excess risk of primary liver cancer observed for women working in laundries and dry-cleaning shops in Denmark is not likely to be explained by exposure to dry-cleaning solvents. Excessive alcohol consumption is not a likely explanation either, and the excess risk therefore remains unexplained.

Indoor exposure to perchloroethylene (PCE) in individuals living with dry-cleaning workers

Perchloroethylene (PCE) is the most widely used solvent in dry-cleaning; it is toxic to the liver, kidney and central nervous system and may be a human carcinogen. PCE levels in the ambient air of dry-cleaners' homes were measured, and samples of end-exhaled air (alveolar air) from subjects who were not themselves occupationally exposed, but who were members of the household of dry-cleaners were compared with samples from the general population. Thirty apartments were visited housing dry-cleaners and their families, and located well away from the dry-cleaning premises. Indoor air samples and alveolar air samples were collected contemporaneously from the dry-cleaners (36) and members of their household (34). The same sampling procedure was followed in 25 private homes where samples of alveolar air were collected from 41 subjects who were not occupationally exposed and who acted as control group. All the samples were analysed by direct-injection gas-chromatography. PCE levels in dry-cleaners' homes proved to be significantly higher than in control houses (geometric means: 265 vs. 2 μg/m 3, P < 0.001). PCE levels in the alveolar air exhaled by dry-cleaners, their family members and control subjects were statistically different (geometric means: 5140, 225 and 3 μg/m 3, respectively; P < 0.001). PCE is a ubiquitous substance in indoor air, but is present at higher concentrations in apartments where dry-cleaners and their families live. Biological monitoring of PCE in alveolar air confirms that family members of dry-cleaners are more exposed than the general population.

Subjective symptom increase among dry-cleaning workers exposed to tetrachloroethylene vapor.

Subjective symptoms, hematology, serum biochemistry and other clinical signs were investigated in 56 dry-cleaning workers exposed to tetrachloroethylene at 20 ppm (as a geometric mean of 8-hr time-weighted average), and the results were compared with the findings in 69 non-exposed controls from the same factories. There were exposure-related increases in the prevalence of subjective symptoms during the work as well as in the past 3 month period, whereas there was no significant changes in hematology. Effects of the exposure on liver and kidney functions were also negative as judged by emission enzyme activities, BUN and creatinine in the serum.

Perchloroethylene Exposure Assessment among Dry Cleaning Workers

Perchloroethylene (Perc), the most widely used solvent in dry cleaning, is toxic to the liver, kidneys, and central nervous system and may be a human carcinogen. In the Detroit area, as part of a project investigating the health status of dry cleaning workers, an exposure assessment was carried out in dry cleaning plants using perchloroethylene. Breath samples were obtained from each participant, and time-weighted average (TWA) breathing zone air samples were obtained using passive dosimeters on a subset expected to experience a range of exposures. Perc in breath and Perc in air were highly correlated (r2=0.75, p<0.0001). On average, operators of dry cleaning equipment experienced significantly more exposure than nonoperators. Also, employees working in shops that use transfer equipment (requiring physical transfer of Perc-saturated clothing from washers to dryers) showed significantly higher exposure than those in shops utilizing dry-to-dry machinery (permitting washing and drying in one machine in a single cycle). One or more air samples in every transfer shop exceeded the recently revised Occupational Safety and Health Administration (OSHA) permissible exposure limit (PEL) of 25 ppm, while no air samples in dry-to-dry shops exceeded this limit. The results suggest concern for exposures to operators in transfer shops and that compliance with the PEL is achievable by engineering controls with presently existing technology.