Estimation of the probability of exposure to machining fluids in a population-based case-control study

We describe an approach for estimating the probability that study subjects were exposed to metalworking fluids (MWFs) in a population-based case-control study of bladder cancer. Study subject reports on the frequency of machining and use of specific MWFs (straight, soluble, and synthetic/semi-synthetic) were used to estimate exposure probability when available. Those reports also were used to develop estimates for job groups, which were then applied to jobs without MWF reports. Estimates using both cases and controls and controls only were developed. The prevalence of machining varied substantially across job groups (0.1->0.9%), with the greatest percentage of jobs that machined being reported by machinists and tool and die workers. Reports of straight and soluble MWF use were fairly consistent across job groups (generally 50-70%). Synthetic MWF use was lower (13-45%). There was little difference in reports by cases and controls vs. controls only. Approximately, 1% of the entire study population was assessed as definitely exposed to straight or soluble fluids in contrast to 0.2% definitely exposed to synthetic/semi-synthetics. A comparison between the reported use of the MWFs and U.S. production levels found high correlations (r generally >0.7). Overall, the method described here is likely to have provided a systematic and reliable ranking that better reflects the variability of exposure to three types of MWFs than approaches applied in the past. [Supplementary materials are available for this article. Go to the publisher's online edition of Journal of Occupational and Environmental Hygiene for the following free supplemental resources: a list of keywords in the occupational histories that were used to link study subjects to the metalworking fluids (MWFs) modules; recommendations from the literature on selection of MWFs based on type of machining operation, the metal being machined and decade; popular additives to MWFs; the number and proportion of controls who reported various MWF responses by job group; the number and proportion of controls assigned to the MWF types by job group and exposure category; and the distribution of cases and controls assigned various levels of probability by MWF type.].

Evaluation of Hypersensitivity Pneumonitis Among Workers Exposed to Metal Removal Fluids

Hypersensitivity pneumonitis (HP) was identified among employees in an automobile parts manufacturing facility. Mycobacteria immunogenum (MI) was identified as a metal removal fluid (MRF) contaminant at this facility and had been identified as a contaminant in other facilities where HP had occurred. We therefore questioned whether measurement of MI-specific cell-mediated immunity would be associated with HP in this facility. We also questioned whether measures of cell-mediated immunity would be more informative about the presence of HP than evaluation of serum anti-MI antibody levels. Workers were categorized for exposure and disease status by questionnaire and review of medical records. Cell-mediated immunity to MI was assessed by measuring in vitro secretion of cytokines (interleukin 8, tumor necrosis factor alpha, and interferon-gamma) from peripheral blood mononuclear cells or anticoagulated whole blood induced by culture with MI antigen. Serum antibodies against MI were also measured. Six study participants met our survey definition for HP and 48 did not. As has been reported for various agents causing HP, serum antibody levels against MI were increased in both exposed workers and workers with HP. Serum antibodies did not distinguish between the two. When expressed as a percentage of secretion induced by lipopolysaccharide, MI induced a significant increase in interleukin-8 secretion in exposed participants' whole blood cultures. There were trends for increased MI-induced secretion of interferon-gamma by peripheral blood mononuclear cells from both exposed workers and workers with HP. However, these trends did not attain statistical significance. Thus, several measures of immunity to MI distinguished between exposed and unexposed workers but not between workers with and without HP. These evaluations of cell-mediated immunity were not more informative than measurement of serum antibodies. As was done at this facility, institution of a comprehensive safety and health plan for MRF is necessary to eliminate (or minimize) health effects related to occupational exposures in the machining environment.

A novel total petroleum hydrocarbon fractionation strategy for human health risk assessment for petroleum hydrocarbon-contaminated site management

Human health risk assessments for petroleum, oil, and lubricant (POL)-contaminated sites are more complicated than for sites contaminated by single compounds due to the complex composition and various analytical methods associated with total petroleum hydrocarbons (TPH). Although several TPH fractionation methods are commonly used, including that of the TPH Criteria Working Group (TPHCWG), an efficient and economical human health risk assessment method is not yet available. To address this concern, a new modified fractionation strategy is recommended in this study, which resolves the problems of the current TPH fractionation methods while retaining reliability in the results. For the purpose of this study, the distribution characteristics of the 13 TPHCWG fractions were examined, and human health risk assessments for the POL-contaminated sites were performed. The results show that aliphatic EC8-16 and aromatic EC10-21 among the 13 TPH fractions are major contributors to human health risks along all exposure routes, making up approximately 96% of the hazard index (HI) of the TPH fractions, on average. Therefore, it is reasonable to concentrate on aliphatic EC8-16 and aromatic EC10-21 fractions, rather than to study all of the TPH fractions, in evaluating human health risk for TPH-contaminated sites.

Environmental liability and life-cycle management of used lubricating oils

Used oil handling, as a business, requires an extensive understanding by management that environmental liabilities exist through its supply chain. Findings from a review of the legal requirements of operating a used oil handling business were: understanding the transfer of ownership of used petroleum hydrocarbons is critical to any such business and how this is documented; used oil handlers are responsible for providing training to their staff, including site personnel and any third party waste contractors, and for communicating best practice procedures relating to the management of used petroleum hydrocarbons to all those individuals and organisations involved in business relationships that the used oil handling companies have; used oil handlers should audit the performance of any third party contractors that it engages to conduct work on behalf of its customers. Hypothetical situations of a company planning to enter the used oil handling market are described in relation to petroleum hydrocarbon wastes it handles to illustrate the range of potential liabilities. Companies proposing to establish a used oil handling business should ensure that they provide accurate advice to its employees, its customer's employees and to its third party contractors, all of which may be responsible for handling used petroleum hydrocarbons as part of the service it intends to provide, and that it has a well documented system addressing how environmental issues are managed.

Prolonged Respiratory Symptoms in Clean-up Workers of thePrestigeOil Spill

RATIONALE

The wreckage of the oil tanker Prestige in November 2002 produced heavy contamination off the coast of Galicia, Spain.

OBJECTIVES

To evaluate the prevalence of respiratory symptoms in local fishermen more than 1 year after having participated in clean-up work.

METHODS

Questionnaires including qualitative and quantitative information about clean-up activities and respiratory symptoms were distributed among associates of 38 fishermen's cooperatives. Both postal and telephone follow-up was performed. The association between participation in clean-up work and respiratory symptoms was evaluated using multiple logistic regression analyses, adjusted for sex, age, and smoking status.

MEASUREMENTS AND MAIN RESULTS

Between January 2004 and February 2005, data were obtained from 6,780 fishermen (response rate, 76%). Sixty-three percent had participated in clean-up operations. Lower respiratory tract symptoms (LRTS) were more prevalent in clean-up workers: odds ratio (OR), 1.73; 95% confidence interval (CI), 1.54-1.94. This association was consistent for men and women, for different fishermen's cooperatives, and for different types of respiratory symptoms, and remained after excluding those who reported anxiety or believed that the oil spill had affected their health (OR, 1.57; 95% CI, 1.37-1.80). The risk of LRTS increased with the number of exposed days, exposed hours per day, and number of activities (linear trend, P < 0.0001). The excess risk of LRTS decreased when more time had elapsed since last exposure: OR, 2.33, 1.69, and 1.24 for less than 14 months, 14-20 months, and more than 20 months, respectively.

CONCLUSIONS

Participation in clean-up work of oil spills may result in prolonged respiratory symptoms that last 1 to 2 years after exposure.

Evaluation of two self-administered questionnaires to ascertain dermatitis among metal workers and its relation with exposure to metal working fluids

We performed an exploratory study to evaluate 2 self-administered questionnaires assessing hand dermatitis and to investigate a possible exposure-response relation between dermal exposure to semi-synthetic metal working fluids (SMWF) and dermatitis. In a cross-sectional survey on dermatitis, a symptom-based questionnaire and a picture-based skin-screening list were applied in 80 SMWF-exposed workers and 67 referents. To evaluate accuracy of the questionnaires, 47 subjects were examined by a dermatologist. Dermal exposure levels to SMWF were assessed on the hands, forearms, and face with an observational method that was validated with a fluorescent-tracer method. The symptom-based questionnaire had a relatively high sensitivity (0.86) but moderate specificity (0.64), the skin-screening list had a low sensitivity (0.36) and a relatively high specificity (0.84). The skin-screening list seemed to represent the more severe cases of dermatitis and showed a significant relation to exposure, for dermatitis on hands, forearms, or face. In epidemiological surveys where workers are not seen by a dermatologist, the skin-screening list seems to be more appropriate to detect cases of dermatitis, as its higher specificity results in less false positives. Alternatively, it would be preferable to apply the symptom-based questionnaire; workers with symptoms should be seen by a dermatologist to identify false positives.

Mutagenicity assessment of produced water during photoelectrocatalytic degradation

Oilfield produced water was treated by photocatalysis, electro-oxidation, and photoelectrocatalysis, respectively. The chemical composition and toxicity of the raw effluent and treated products were assessed by chemical and mutagenicity analysis. The raw effluent exhibited mutagenic activity in both strains of Salmonella typhimurium. The lowest concentration of the dichloromethane extract capable of inducing a positive response in strains TA98 and TA100 were as low as 4 and 5 microg/plate, respectively. All three technologies could detoxify direct-acting mutagenic organic pollutants efficiently, although they could not completely eliminate mutagenicity in the water after 60 min of treatment. At equivalent doses, photoelectrocatalysis exhibited the greatest capability to reduce genotoxicity, whereas photocatalysis was the least effective and did not cause appreciable change in mutagenicity. The gas chromatography-mass spectrometry (GC-MS) analysis revealed that n-alkanes (259.4 ng/L) and phenolic compounds (2,501.4 ng/L) were the main organic constituents in the oilfield produced water. Thus, the results of both biological and chemical analysis indicate that photoelectocatalysis was the most effective technology for degradation of oilfield wastewater.

Lung Cancer Mortality and Carbon Black Exposure: A Nested Case???Control Study at a German Carbon Black Production Plant

OBJECTIVE

The objective of this study was to conduct a case-control study of lung cancer nested within a cohort of 1528 German carbon black workers, 1976-1998.

METHODS

The authors conducted risk-set sampling of two controls matched on year of birth and conditional logistic regression modeling of cumulative carbon black exposure, duration of work in different departments, feedstock contact, asbestos exposure, smoking, age at hire, exposures before the carbon black job, and serving as a soldier in World War II or being a prisoner of war. Analyses were performed with both the full cohort and members of an inception cohort subset. Exposures were lagged by 10 years.

RESULTS

Analysis of 50 lung cancer deaths showed no association to carbon black exposure.

CONCLUSIONS

Carbon black exposure was not linked to lung cancer risk. Suggestions of positive associations with asbestos exposure, feedstock contact, and work in specific departments are inconclusive due to small numbers.

[Influence of ecological factors on the frequency of respiratory diseases in children in the zone of oil catastrophe]

In the village Ninotsminda, district of Sagarejo, the important environmental contamination was provoked by the explosion of oil bore-hole. Intoxication of the children' s respiratory system with the oil-associated gases was studied. 420 children, residing at the contaminated district of Ninotsminda and 50 children, residing at the nearby ecologically clear village Badiauri (in the distance of 6 km) were investigated. The observations were done quarterly and included clinical-laboratory investigations. As a result of the study it was shown that the frequency of different diseases was increased sharply among the children from the in catastrophe zone in comparison with the control zone, diseases of upper respiratory system dominated in the nozological structures of diseases.

Occupational asthma in industry

Occupational or professional asthma is defined as adult asthma, i.e., an inflammatory respiratory disease characterized by the presence of variable airflow limitation or bronchial hyperreactivity secondary to conditions and causes associated with a given occupational or working environment - not with stimuli found outside the workplace. Depending on the physiopathological mechanism involved, a distinction is made between immune asthma (with or without IgE mediation) and non-immune asthma. It is difficult to establish the relationship among the symptoms of asthma, the patient's professional activity and the presence or absence of sensitization to certain agents in the working environment. Guided compilation of the case history and measurement of nonspecific bronchial hyperreactivity and bronchial inflammation are currently essential in the diagnostic approach to occupational asthma. Whenever possible, allergists should establish the cause-effect relationship in occupational asthma, as required by the medical-legal and social implications of the disease. Occupational asthma remains a minority diagnosis among occupational diseases in general. Adequate personnel training and the creation of diagnostic centers may help to ensure correct and rapid detection of this disease.

Occupational allergic contact dermatitis from N,N-methylene-bis-5-methyl-oxazolidine in coolant oils

Contact with metal working fluids (MWF) is an important factor in the development of occupational hand dermatitis in patients working in the metal processing industry. Biocides are added to MWF as preservatives and are known sensitizers. We analysed 318 patch test reactions to N,N-methylene-bis-5-methyl-oxazolidine 1% in petrolatum (5-methyloxazolidine, Grotan OX, CAS no. 66204-44-2, a formaldehyde releasing biocide) present in coolant oils in patients exposed to MWF and with suspected occupational dermatitis (OD). Positive allergic reactions were noted in 15 (4.7%) cases. In 7 (47%) cases, we were able to confirm relevance by examining the material safety data sheets and these showed that N,N-methylene-bis-5-methyl-oxazolidine was present in the oils used by the patients. No certain relevance could be proved in 8 cases, but in these instances, further information on the biocides used in the oils could not be obtained. Positive reactions to formaldehyde were seen in 11 (73%) patients. Sensitization either to this biocide and/or formaldehyde allergy was considered to have been likely to have made a contribution to the workers' dermatitis.

Hypersensitivity pneumonitis due to metal working fluids: Sporadic or under reported?

BACKGROUND

Occupational exposure to metal working fluids (MWF) is common with over 1.2 million workers in the United States involved in machine finishing, machine tooling, and other metalworking operations. MWF is a known cause of hypersensitivity pneumonitis (HP). Recent reports of outbreaks of hypersensitivity HP secondary to exposure to MWF are reported.

DESIGN

Cases were identified through the Occupational Disease surveillance system in the State of Michigan and from referrals for evaluation to the Division of Occupational and Environmental Medicine at Michigan State University (MSU). Each patient underwent a clinical examination including an occupational history, lung function studies, radiographic imaging, and in some cases lung biopsies. Following the diagnosis of definite HP, an industrial hygiene investigation was carried out, which included a plant walk-through, and review of the "Injury and Illness" log. Air monitoring and microbial sampling results were reviewed.

RESULTS

As part of Michigan's mandatory surveillance system for occupational illnesses, seven cases of suspected HP were identified in 2003-2004 from three facilities manufacturing automobile parts in Michigan. Each plant used semi-synthetic MWFs, and conducted a MWF management program including biocide additions. Two facilities had recently changed the MWF before the cases arose. Growth of mycobacteria was found in these two MWFs. Breathing zone samples for particulates of two employees in plant A (two cases) ranged from 0.48 to 0.56 mg/m3. In plant B (four cases), two employees' sampling results ranged from 0.10 to 0.14 mg/m3. No air sampling data were available from plant C.

CONCLUSION

Hypersensitivity pneumonitis due to exposure to MWFs is under-recognized by health care providers, and current surveillance systems are inadequate to provide a true estimate of its occurrence. HP arose from environments with exposures well below the Occupational Safety and Health Administration (OSHA) permissible exposure limit (PEL) for MWF, and in one case from exposures well below the National Institute of Occupational Safety and Health (NIOSH) recommended exposure limit (REL). The sporadic nature of reports of HP in relationship to MWF probably represents a combination of workplace changes that cause the disease and inadequate recognition and reporting of the disease when it does occur. Physician awareness of HP secondary to MWF and an effective medical surveillance program are necessary to better understanding the epidemiology and prevention of this disease.

Sarcoidal Granuloma Developing Not Only at the Entry Site of Industrial Lubricating Oil, but Also at a Regional Lymph Node and Entry Points of Venepuncture

We describe a 40-year-old male who presented with sarcoidal granulomas not only at the entry site of an industrial lubricating oil containing silicone in the right thumb, but also in a regional lymph node and at the entry points of venepuncture in both forearms. Laboratory tests and chest X-ray showed no evidence of sarcoidosis.

Proteomics analysis revealed changes in rat bronchoalveolar lavage fluid proteins associated with oil mist exposure

Exposure to oil mist has been associated with a variety of acute and chronic respiratory effects. Using proteomics approaches to investigate exposure-associated proteins may provide useful information to understand the mechanisms of associated respiratory effects. The aim of this study was to investigate changes in rat bronchoalveolar lavage fluid proteins associated with oil mist exposure using nano-HPLC-ESI-MS/MS. The results revealed that 29 proteins exhibited significant changes after exposure. These proteins included surfactant-associated proteins (SP-A and SP-D), inflammatory proteins (complement component 3, immunoglobulins, lysozyme, etc.), growth factors (e.g., transforming growth factor alpha (TGF-alpha)), calcium-binding proteins (calcyclin, calgranulin A, calreticulin, and calvasculin), and other proteins (e.g., cathepsin D, saposin, and intestinal trefoil factor). To further evaluate changes in protein levels, a simple quantitative strategy was developed in this study. A large decrease in protein levels of SP-A and SP-D (0.24- and 0.38-fold, respectively) following exposure was observed. In contrast, protein levels of TGF-alpha and calcium-binding proteins were significantly increased (4.46- and 1.4-1.8-fold, respectively). Due to the diverse functions of these proteins, the results might contribute to understand the mechanisms involved in lung disorders induced by oil mist exposure.

Aplastic Anemia in a Professional Musician Exposed to Instrument Polish

Chemicals are known to cause toxin-induced aplastic anemia. However, some chemicals documented in only a few cases to possess only a possibility of toxic potential may also be responsible for the development of aplastic anemia. This report presents a case of a string musician with bone marrow failure. The patient used a certain type of polish (komalak) to shine his musical instrument and did this frequently. He presented with nasal bleeding, and a workup on admission revealed pancytopenia. Aplastic anemia was diagnosed on the basis of bone marrow histology results. An analysis for gene polymorphism related to the metabolic detoxification enzymes glutathione S-transferase and N-acetyltransferase 2 indicated that the patient was genetically susceptible to developing toxicity. This case suggests that frequent use of this polish may cause a toxic effect that leads to bone marrow failure. Musicians should be made aware of the risks associated with these types of chemicals.

A biological approach to characterizing exposure to metalworking fluids and risk of prostate cancer (United States)

OBJECTIVE

Prostate cancer is hormone-related and chemicals that interfere with hormones may contribute to carcinogenesis. In a cohort of autoworkers we characterized exposure to metalworking fluids (MWF) into age windows with homogenous biological risk for prostate cancer, and examined exposure-response relationships using semi-parametric modeling.

METHODS

Incident cases (n=872) were identified via Michigan cancer registry from 1985 through 2000. Controls were selected using incidence-density sampling, 5:1 ratio. Using a hormonal-based model, exposure was accumulated in three windows: (1) late puberty, (2) adulthood, and (3) middle age. We used penalized splines to model risk as a smooth function of exposure, and controlled for race and calendar year of diagnosis in a Cox model.

RESULTS

Risk of prostate cancer linearly increased with exposure to straight MWF in the first window, with a relative risk of 2.4 per 10 mg/m(3)-years. Autoworkers exposed to MWF at a young age also had an increased risk associated with MWF exposure incurred later in life. For soluble MWF there was a slightly increased risk in the third window.

CONCLUSIONS

Exposure characterization based on a hormonal model identified heightened risk with early age of exposure to straight MWF. Results also support a long latency period for exposure related prostate cancer.

Patch test results with the metalworking fluid series of the German Contact Dermatitis Research Group (DKG)

Based on the information of the interdisciplinary task force on allergy diagnostics in the metal branch, in 2001, the German Contact Dermatitis Research Group (DKG) compiled two metalworking fluid (MWF) test series with currently and previously used components, respectively. After 2 years of patch testing, we present results obtained with these series, based on data of the Information Network of Departments of Dermatology (IVDK). 251 metalworkers who were patch tested because of suspected MWF dermatitis in 2002 and 2003 were included in this retrospective data analysis. Of these, 206 were tested with the current MWF series and 155 with the historical MWF series. Among the current MWF allergens, monoethanolamine ranked 1st with 11.6% positive reactions. Diethanolamine (3.0%), triethanolamine (1.1%), and diglycolamine (1.9%) elicited positive reactions far less frequently. Allergic reactions to p-aminoazobenzene were frequently observed (6.0%), but the relevance of these reactions is still obscure. Positive reactions to biocides ranged from 4.5% for Bioban CS 1135 to 0.5% for iodopropynyl butylcarbamate and 2-phenoxyethanol. Concomitant reactions to formaldehyde, which caused positive reactions in 3.3%, and formaldehyde releasers occurred to varying extents without conclusive pattern. No positive reactions were seen to dibutyl phthalate, di-2-ethylhexyl phthalate, tricresyl phosphate, isopropyl myristate or benzotriazole. With the historical MWF test series, positive reactions to methyldibromo glutaronitrile (MDBGN) were observed most frequently. However, sensitization via allergen sources other than MWF seems likely, as MDBGN, during the study period, has been one of the most frequent preservative allergens in cosmetics and body care products. Other historical MWF allergens comprised morpholinyl mercaptobenzothiazole (3.3%), benzisothiazolinone (BIT; 2.0%) and Bioban P 1487(1.3%). BIT is currently used in MWF again, so it was shifted to the current MWF test series. As decreasing reaction frequencies to former MWF allergens that are no longer used can be expected, the historical series should be re-evaluated after some years. The test series with current MWF allergens has to be kept up-to-date based on information from industry and to be kept concise by eliminating test substances which never cause positive reactions.

Patch testing with metalworking fluids from the patient's workplace

In view of the wide variety of components currently used in metalworking fluids (MWF), relevant contact sensitizations may be overlooked, because commercially available MWF test series cannot cover the full spectrum. Hence, patch testing with MWF from the patient's workplace is an important additional diagnostic tool. However, recommendations on how to perform such patch tests vary. We retrospectively analyzed patch test data of the Department of Dermatology in Dortmund, 1992-2003. In 141 metalworkers tested because of suspected occupational contact dermatitis due to MWF, 829 patch tests with 306 samples of MWF were performed. Water-based MWF (wb MWF) were mainly tested in 2 dilution series, i.e. pure (workplace concentration), 10% aq. and 1% aq., and pure, 50% aq. and 10% aq. Positive reactions to wb MWF occurred in 27 patients. Patch testing with wb MWF at workplace concentration resulted in 16.1% (39/242) positive reactions, with a positivity ratio of 69% and a reaction index of 0. From the analysis of reaction patterns and concomitant reactions, we conclude that most of these positive reactions indicated true contact allergy. With lower concentrations, relevant allergic reactions may be missed. Neat oils were tested as is or diluted from 1 to 50% in olive oil, but no reactions at all were observed. For optimum benefit of patch testing with MWF from the patient's workplace, breakdown testing is recommended. To overcome the time-consuming difficulties associated with this procedure, we propose a centre for information and documentation of contact allergies due to occupational exposure. Furthermore, full declaration of MWF ingredients is desirable.

Risk of upper aerodigestive tract cancers in a case-cohort study of autoworkers exposed to metalworking fluids

AIMS

To re-examine aerodigestive cancer risk in a cohort of autoworkers exposed to metal working fluids (MWF), using improved case definition and more recently diagnosed cases.

METHODS

The autoworker cohort included 31 100 hourly workers alive on 1 January 1985 who worked at three automobile plants in Michigan. A case-cohort design was carried out that included incident cases of cancers of the larynx, oesophagus, and stomach, and a 10% sample of the cohort. A Cox proportional hazards model was used to estimate MWF exposure effects. The smoothing method of penalised splines was used to explore the shape of the underlying exposure-response curves.

RESULTS

The most important finding was the association between larynx cancer incidence and cumulative straight MWF exposure. The results for oesophageal cancer were less consistent. For stomach cancer there was no evidence of excess risk.

CONCLUSION

This association between larynx cancer and straight MWF exposures was consistent with a previous finding in this cohort, providing further support for a causal relation.

Aerosol mapping of a facility with multiple cases of hypersensitivity pneumonitis: demonstration of mist reduction and a possible dose/response relationship

Recent outbreaks of hypersensitivity pneumonitis (HP) have been associated with exposures to metalworking (MWF) fluid aerosols. Mycobacteria present in mismanaged fluids have been suggested as the likely culprit. In January 2001, three machinists at a machining plant were hospitalized with HP. Subsequently, additional HP cases developed as well as cases of bronchitis and occupational asthma. In October 2001, an aerosol concentration map was constructed to advise on priorities for corrective actions. In April 2002 after installation of mist collectors, a second map was generated. Mist reductions varied from about 75 percent to an increase of about 20 percent. Mist concentrations increased in the areas near an uncontrolled transfer line. Subsequent to the first mapping exercise, the exposures of 30 HP cases were classified as low, medium, and high based on job location and the map. There were 6 cases among low exposure jobs (4% of exposed), 14 cases among medium exposure jobs (19% of exposed), and 10 cases among high exposure jobs (34% of exposed), suggesting a relation between exposure to contaminated metalworking fluid mist and the development of HP. A combination of interventions (fluid management, mist control, improved fresh air ventilation, and medical surveillance/restriction) eliminated any new cases 11 months after the first diagnosis of HP.

Investigating respiratory responses to metalworking fluid exposure

In response to worker and union representative concerns, the association between metalworking fluid exposure and respiratory symptoms was investigated in a cross-sectional survey, in a large automotive machining location. A self-administered respiratory symptom-screening questionnaire was sent to 2935 current employees. MWF exposure levels were assigned to respondents on a departmental basis based on average and "peak" area aerosol measurements. MWF exposure, years in the plant, and smoking status were regressed on presence or absence of daily or weekly respiratory symptoms, as well as upper and lower respiratory symptom groupings derived from principal components factor analysis. The response rate was 81 percent. Symptom prevalence was high: 29 percent of subjects reported weekly or daily phlegm; 23 percent, dry cough; 42 percent, runny or plugged nose. Average aerosol concentration in departments with exposure ranged from 0.02 to 0.84 mg/m(3), and peak levels from 0.02 to 2.85 mg/m(3). Average exposures ranging from 0.25 to 0.84 mg/m(3), as compared to exposures in the range of 0.02 to 0.09 mg/m(3), were statistically significantly associated with wheezing, chest tightness, sore throat, and hoarse throat, as well as with the upper respiratory symptom grouping. When peak exposure was included in the regression, it exerted a stronger effect than average exposure level on dry cough, phlegm, wheezing, fever/chills, and hoarse throat, as well as on upper and lower respiratory symptom groupings. These effects were independent of smoking status. Exposure-symptom trends for the average and peak departmental area concentration categories were statistically significant for the upper and lower respiratory symptom groupings and for most individual symptoms. We have observed an association of increasing upper and lower respiratory symptoms with estimated MWF exposure, measured independently, at average departmental aerosol concentrations well below the NIOSH recommended personal exposure level of 0.5 mg/m(3). The results have been used to prioritize exposure reduction efforts in the workplace.

Occupational exposure to chemical and petrochemical industries and bladder cancer risk in four western Canadian provinces

Occupational factors have been proposed to play a critical role in bladder cancer. This population-based case-control study was conducted to confirm the association between selected occupational and non-occupational risk factors and risk of bladder cancer using data collected from the four western Canadian provinces. Unconditional logistic regression analyses were based on 549 histologically confirmed bladder cancer cases and 1099 controls. Bladder cancer risk was found to increase with increasing pack-years of cigarette smoking with an odds ratio (OR) in the highest quartile of 3.32 (95% confidence interval [CI], 2.28-4.82). A dose-response relationship was demonstrated between bladder cancer and pack-years of smoking (p < 0.0001). A positive trend was observed with coffee consumption in men (p < 0.0001), with the highest risk in the highest category of exposure: drinkers of four cups or more per day had an OR of 1.77 (95% CI 1.11-2.82). Increased bladder cancer risk was associated with self-reported exposure at work to several chemicals: asbestos (OR 1.69 [95% CI 1.07-2.65]); mineral, cutting or lubricating oil (1.64 [95% CI 1.06-2.55]); benzidine (2.20 [95% CI 1.00-4.87]). The population attributable fraction (PAF) estimates were 51% for cigarette smoking, 17% for heavy coffee consumption, 10% for mineral, cutting or lubricating oil exposure, 6% for asbestos exposure, and 1% for benzidine exposure. Although self-reported chemical exposures have important limitations, the findings are suggestive of increased risk for several associations previously reported between chemical agents or industries and risk of bladder cancer.

A mortality and morbidity study of refinery and petrochemical employees in Louisiana

AIMS

To examine the mortality experience of 4221 employees from 1973 to 1999 and the illness absence patterns for 2203 employees from 1990 to 1999 of a chemical and refinery facility in Louisiana.

METHODS

Mortality and illness absence data were extracted from the Shell Oil Company's health surveillance system (HSS). The standardised mortality ratio was used as a measure of mortality risk. Morbidity frequency and duration of absence were calculated by age, sex, and four health risk factors (cigarette smoking, high blood pressure, hypercholesterolaemia, and obesity).

RESULTS

Male employees experienced a significant deficit in mortality for all causes of death, all cancers, lung cancer, heart disease, and respiratory disease compared with the corresponding US population. Brain cancer was non-significantly increased, with six observed and five expected deaths; mortality from leukaemia was consistently lower than expected. The majority of employees had no illness absences of six days or longer during the 10 year study period. The loss of productivity (in terms of days of absence) was greater for employees with health risk factors. Ever smoking male employees had a 79% increase of heart disease and more than 50% higher rates of respiratory disease and musculoskeletal disorders compared to non-smokers. Smokers were absent 2.9 and 1.6 more days than non-smokers and ex-smokers, respectively.

CONCLUSIONS

Regardless of the comparison population, significantly fewer deaths were seen for all causes combined, all cancers, lung cancer, heart disease, or non-malignant respiratory disease. Illness absence rates and duration were higher among employees with health risk factors.

Role of underlying pulmonary obstruction in short-term airway response to metal working fluid exposure: a reanalysis

BACKGROUND

Among epidemiologic studies that found evidence for associations between exposures to metal working fluids (MWF) and pulmonary function impairments, one found effects restricted to workers with fixed obstruction at baseline. We reanalyzed a previously published study on MWF exposure and cross-shift pulmonary function to further evaluate this finding.

METHODS

Pulmonary function was measured cross-shift on Monday and Friday in 131 male automotive workers. Quantitative personal MWF exposure data were available. Those with an FEV(1)/FVC ratio of <or=0.72 were considered obstructed.

RESULTS

There was a trend towards increasing incidence of cross-shift decrement in FEV(1) as MWF exposure increased in the full cohort as well as when the results were restricted to the 19 (14.5%) who were obstructed. Those with obstruction were slightly more likely to show decrements in FEV(1) on Fridays. Removing the obstructed subgroup did not appear to substantially weaken the exposure-response relation.

CONCLUSIONS

No important differences were found in cross-shift effects of MWF between obstructed and non-obstructed workers.

[Hand injuries resulting from high-pressure injection: lesions specific to industrial oil]

Nineteen cases of high pressure injection injuries in the hand were treated between 1973 and 1998. Same surgical treatment plan was followed in all cases: excision of the penetration point, irrigation, debridement and synovectomy if opening of the flexor sheath was noted, and skin closure to allow early mobilisation. All cases concerned men, work injuries, and volar aspect of the hand. The elapsed time between injection and initial surgery ranged from 1 hour to 1 month with a mean of 6.5 days. Eighteen patients out of 19 were reviewed with a mean follow up of 12 years. In 11/19 cases, (58%) oil was injected. The results of oil injection cases have been analysed: the quantity of oil and the preoperative delay (if more ten hours) are associated with poor functional results or complications. Two amputations, two cases of skin necrosis at the injection point, and one case of infection are reported. One case of oleoma of the thumb is described. The specificity of injuries by industrial oil under pressure must be known: paint or white spirit are more toxic than oil which was in all cases injected in the dominant hand (no high pressure injection tool but a defect in the pipe). An important inflammatory reaction with functional sequelae is caused by foreign bodies in oil. Extraction of oil off the injured tissues is difficult because oil is not visible. A specific information is necessary for farmers and truck driver, very exposed population.

Smoothing in survival models: an application to workers exposed to metalworking fluids

BACKGROUND In occupational epidemiology it is typically assumed that the relation between exposure, possibly transformed, and the risk of an adverse health outcome is linear in the parameters. Alternatively, exposure is transformed into a categorical variable. METHODS We used nonparametric regression to examine the linearity assumption for prostate and brain cancer mortality in a cohort of 46,400 autoworkers exposed to metalworking fluids. Using a nested case-control sample, we fit Cox proportional hazards models with penalized splines, in which we allowed the risk to be a smooth function of exposure to each of three types of metalworking fluids. Two dose metrics in addition to cumulative exposure were considered. RESULTS The shape of the dose-response curve for soluble metalworking fluids and each cancer was approximately piecewise linear, with a small increase in risk at lower exposures followed by a larger increase at exposures above a critical point. CONCLUSIONS This example illustrates that the penalized spline methodology can be easily applied to cohort studies to estimate smooth exposure-response curves.

Fragrance chemicals in domestic and occupational products

Epidemiological studies have described an increasing prevalence of fragrance allergy and indicated an association with hand eczema. 59 domestic and occupational products intended for hand exposure were subjected to gas chromatography-mass spectrometric (GC-MS) analyses to test the hypothesis that fragrance chemicals known to have the potential to cause contact allergy but not included in fragrance mix (FM) may be common ingredients in these products. A quantitative analysis of 19 selected fragrances was performed by GC-MS. Further analysis of GC-MS data revealed the presence of 43 other fragrance chemicals/groups of fragrance chemicals in the products investigated. Among the 19 target substances the most commonly detected were limonene in 78%, linalool in 61% and citronellol in 47% of the products investigated. The FM ingredients were present in these products with the following frequencies: oak moss (evernic acid methylester) 2%, cinnamic alcohol 2%, cinnamic aldehyde (cinnamal) 3%, isoeugenol 5%, alpha-amylcinnamic aldehyde (amyl cinnamal) 8%, hydroxycitronellal 12%, eugenol 27%, and geraniol 41%. Thus, the chemical analyses of domestic and occupational products indicates that investigation of potential contact allergy related to these products types should consider fragrance allergens additional to those in the FM, since these may occur with high frequency.

A model for predicting endotoxin concentrations in metalworking fluid sumps in small machine shops

METHODS

In British Columbia, Canada, nineteen small machine shops which used water-based metalworking fluids (MWF) were examined. One bulk MWF sample was taken from each independent sump (N=140) and tested for endotoxin using the Limulus Amoebocyte Lysate assay. Factors that might influence the MWF sump endotoxin concentration were investigated using mixed effect multiple regression modelling to control for repeated measures within shops.

RESULTS

The geometric mean (GM) endotoxin concentration was 6791 EU/ml. Contamination of MWF with tramp oil, MWF pH, MWF temperature, and MWF type were significant predictors of sump fluid endotoxin concentration (model P=0.0001, ordinary least squares R(2) =0.36). Concentrations of endotoxin in sump fluids were increased by MWF contamination with tramp oils such as hydraulic oils, preservative oils, spindle oils, slidway lubricants, gear lubricants, and greases (model predicted GM=17400 EU/ml vs. 1600 EU/ml without tramp oil). Concentrations were also elevated where pH was lower than 8.5 (predicted GM=10600, vs 3600 EU/ml for pH 8.5 to 9.5), where soluble fluids were used (predicted GM=11800 vs. 2800 EU/ml for synthetic fluids), and where sump fluid temperatures were higher (predicted GM=2600 EU/ml at 11 degrees C vs. 21500 EU/ml at 32 degrees C). The within-shop correlation of sump bulk fluid endotoxin concentrations was 38%.

CONCLUSIONS

Minimizing tramp oil contamination, using synthetic fluids, and monitoring pH and temperature would be valuable tools for controlling endotoxin contamination in MWF sumps. In addition, since there was correlation within-shop, contamination of one sump in a shop may suggest changing the fluids in all.

Exposure to organic solvents during cosmetic finishing of cars

The objectives of this study were to assess the exposure to organic solvents during degreasing, washing and polishing of cars, and to obtain information about acute health symptoms in car-finishing workers. Fifteen car shops participated in this study, and at these locations 36 workers had car finishing as their main working task. All 36 car-finishing workers and 17 randomly selected office workers from six of these car shops completed questionnaires on acute health symptoms. Personal monitoring of exposure to organic solvents was carried out in three representative shops. The highest exposure levels were found during degreasing of new cars, the median level of aliphatic hydrocarbons (C9-C13) being 22 p.p.m. (range 7-215 p.p.m.). This exposure level represents 50% (range 20-540%) of the Norwegian 8 h limit value for additive factor for these compounds. Only 28% of the workers used gas respirators regularly during this process. Very low exposure levels were detected during washing of second-hand cars and during polishing processes. The present study shows that car-finishing workers are exposed to high levels of organic solvents only for short periods of time. It seems that they are not adequately protected during these periods. However, the presence of acute symptoms was low, i.e. comparable to the prevalences in the reference group.

Erythema multiforme-like eruption associated with contact dermatitis to cutting oil

A 48-year-old Japanese man developed coalesced erythema multiforme-like lesions on the forearms and the dorsa of hands that were exposed to a cutting oil product. Subsequently, multiple, round erythematous lesions with iris formation occurred on the trunk and four extremities that had no direct contact with the oil. It is suggested that erythema multiforme can be induced via some allergic processes following a contact reaction.

Functional outcome of high-pressure injection injuries of the hand

BACKGROUND

High-pressure injection (HPI) injury of the hand is a serious injury that can be potentially devastating. There have been a number of publications on the results of its treatment, but we are not aware of a report on the functional outcome of these hands.

METHODS

We assessed the functional outcome of 15 patients with HPI injuries. All patients were treated operatively, with a mean delay of 11.7 hours. The patients were examined by a doctor and an occupational therapist using a work simulator.

RESULTS

Our study revealed a significant reduction of static and dynamic muscle testing parameters compared with the uninjured hand. Six patients lost a digit and four patients had to change their occupation after the injury.

CONCLUSION

Deterioration of hand function is a predictable outcome of HPI injury. This information should be shared with the patient at the outset so as to avoid subsequent disappointment.

Papuloverrucous colloid milium: an occupational variant

We report a case of adult colloid milium in a 47-year-old mechanic with a long history of professional contact with lubricating oils and of sun exposure. In addition to the typical translucent papules seen on the forehead, there were warty papules on the backs of both hands with unusual histological and ultrastructural features: marked hyperplasia of the epidermis with orthokeratotic hyperkeratosis and papillary deposits of colloid material that were contiguous with the basal layer of the epidermis. The hand lesions caused by occupational exposure to mineral oils and solar radiation represent an occupational variant of adult colloid milium.

Powdering floor polish and mucous membrane irritation in secondary school pupils

OBJECTIVES

Acrylate-styrene copolymer polish has been used to protect the surface of linoleum flooring since the 1960s. Problems with powdering of floor polish were observed at an early stage. In a secondary school in Linköping, Sweden, this phenomenon occurred in the winter of 1994-1995 and the pupils frequently reported irritative symptoms from the eyes and airways. This study was undertaken to assess the potential effect of powdering floor polish on the mucous membranes of the eyes and respiratory tract.

METHODS

Repeated questionnaire-based surveys were conducted with identical questions in the spring of 1995 (during the powdering period) and in the autumn of 1995 (after the polish was removed). The questions dealt with irritative symptoms from the nose, eye, throat and lower respiratory tract.

RESULTS

A preventive effect related to the removal of polish was found for irritative symptoms in all locations mentioned above, but was particularly clear for the lower respiratory tract (prevalence rate ratio = 0.37, 95% CI = 0.23-0.59).

CONCLUSIONS

The results of this study indicate that the powdering of floor polish may cause irritative symptoms from the eyes and airways in school children.

[Occupational exposure to organic solvents and pregnancy. Review of current epidemiologic knowledge]

The findings and methodological issues of recent epidemiological studies (1989-1999) on adverse developmental effects of maternal occupational exposure to organic solvents are reviewed. Several studies suggest the possibility of a moderate increase in the risk of spontaneous abortion and congenital malformations, especially facial clefts, associated with maternal exposure to solvents. A common methodological weakness of these studies is the inaccuracy of data on exposures. Positive findings encourage further epidemiological studies of high-quality design and use of protective measures to minimize exposure to these agents from the preconceptional period to the end of pregnancy.

Mycobacterial contamination of metalworking fluids: involvement of a possible new taxon of rapidly growing mycobacteria

Contamination of air and metalworking fluid (MWF) systems with a rapidly growing mycobacterium (RGM) was detected in 1995 in a single manufacturing plant with recent cases of hypersensitivity pneumonitis (HP). Extensive environmental sampling was performed to determine the extent of the contamination and its variability over time. RGM were present in multiple indoor air samples, 100% of the central MWF storage tanks, and 75% of the freestanding cutting, drilling, and grinding machines. With one exception, contamination was limited to a recently introduced formulation (brand) of semisynthetic MWF used in 95% of the facility's machining operations. In general, the mycobacterial counts were stable over time, with the degree of contamination ranging from 10(2)-10(7) colony forming units (CFU)/mL. A few systems were culture positive for the mycobacterium (> 10(1) CFU/mL), changed to culture negative (< 10(1) CFU/mL), then changed back to culture positive without explanation. Samples obtained from diluted (5%) but unused MWF, a replenishment line with 2% unused MWF, an MWF pasteurizer, city water, and deionized water were culture negative for this species of mycobacterium. Inoculation and growth studies demonstrated that this mycobacterium does not grow in liquid samples of 5% unused MWF. By molecular techniques, the mycobacterial isolates consisted of a single strain and represented a previously undescribed taxon closely related to Mycobacterium chelonae/abscessus. The relationship of this mycobacterium to the cases of HP is unknown.

China's "market economics in command": footwear workers' health in jeopardy

This study of occupational safety and health (OSH) problems in the footwear industry in China, the world's largest shoemaker, is based on four years of research in China supplemented by research in Taiwan, Australia, and the United States. With the advent of the economic reforms of the early 1980s, the Chinese state is being driven by an economic imperative under which the profit motive overrides other concerns, causing a deterioration in OSH conditions. Footwear workers are being exposed to high levels of benzene, toluene, and other toxic solvents contained in the adhesives used in the shoe-making process. Many workers have been afflicted with aplastic anemia, leukemia, and other health problems. Most of China's current permissible exposure limits to toxins are either outdated or underenforced. As a result, the Chinese state's protection of footwear workers' health is inadequate. The article aims to draw the attention of the international OSH community to the importance of setting specific exposure standards for the footwear industry worldwide.

Influence of paternal exposure to oil and oil products on time to pregnancy and spontaneous abortions

The objective of this study was to evaluate the influence of exposure to oil and oil products among men on the time taken for their wives to conceive and on the incidence of spontaneous abortion among them. A cross-sectional study was performed by posting questionnaires to 1,269 men employed as offshore mechanics, offshore operators, offshore drilling personnel, car mechanics (the 'exposed' occupations) and carpenters ('unexposed'). The married men were asked to give a separate questionnaire to their wives for details about their pregnancies. The time elapsed between the beginning of coitus without contraception and the wife becoming pregnant (time to pregnancy) was analyzed with Cox regression analysis by calculating fecundability ratios for the pregnancies for the men exposed to oil and oil products as compared with the men who were not exposed. Spontaneous abortions were analyzed with logistic regression by calculating odds ratios for the pregnancies in which the men were exposed vs. not exposed. A total of 741 (58%) men returned the questionnaires. A total of 301 pregnancies were analyzed for time taken to conceive and 580 for spontaneous abortion. The results were adjusted for variables that could significantly influence conception time (previous infections of the reproductive system and coffee drinking) or the incidence of spontaneous abortion (mother's age, parity and smoking). The outcomes between the exposed and unexposed pregnancies showed no significant differences. Car mechanics had a lower fecundability ratio before 1992 than after 1992. Paternal exposure to hydrocarbons in the occupations studied did not seem to have had a major influence on time to conception or the incidence of spontaneous abortion among the wives of the men exposed to oil products.

Cancer mortality among workers exposed to chemicals during uranium processing

Data provided by the Comprehensive Epidemiology Data Resource allowed us to study patterns of cancer mortality as experienced by 3814 uranium-processing workers employed at the Fernald Feed Materials Production Center in Fernald, Ohio. Using risk-set analyses for cohorts, we estimated the effects of exposure to trichloroethylene, cutting fluids, and kerosene on cancer mortality. Our results suggest that workers who were exposed to trichloroethylene experienced an increase in mortality from cancers of the liver. Cutting-fluid exposure was found to be strongly associated with laryngeal cancers and, furthermore, with brain, hemato- and lymphopoietic system, bladder, and kidney cancer mortality. Kerosene exposure increased the rate of death from several digestive-tract cancers (esophageal, stomach, pancreatic, colon, and rectal cancers) and from prostate cancer. Effect estimates for these cancers increased with duration and level of exposure and were stronger when exposure was lagged.