Failure of antimony trioxide to induce micronuclei or chromosomal aberrations in rat bone-marrow after sub-chronic oral dosing

Antimony trioxide (Sb2O3, CAS 1309-64-4) is widely used as a flame retardant synergist in a number of household products, as a fining agent in glass manufacture, and as a catalyst in the manufacture of various types of polyester plastics. It does not induce point mutations in bacteria or mammalian cells, but is able to induce chromosomal aberrations (CA) in cultured cells in vitro. Although no CA or micronuclei (MN) have been induced after acute oral dosing of mice, repeated oral dosing for 14 or 21 days resulted in increased CA in one report, but did not result in increased MN in another. In order to further investigate its in vivo genotoxicity, Sb2O3 was dosed orally to groups of rats for 21 days at 250, 500 and 1000 mg/kg day. There were no clinical signs of toxicity in the Sb2O3-exposed animals except for some reductions in body-weight gain in the top dose group. Toxicokinetic measurements in a separate study confirmed bone-marrow exposure, and at higher levels than would have been achieved by single oral dosing. Large numbers of cells were scored for CA (600 metaphases/sex group) and MN (12,000 PCE/sex group) but frequencies of CA or MN in Sb2O3-treated rats were very similar to controls, and not biologically or statistically different, at all doses. These results provide further indication that Sb2O3 is not genotoxic to the bone marrow of rodents after 21 days of oral administration at high doses close to the maximum tolerated dose.     

Sensitive biomarker of polycyclic aromatic hydrocarbons (PAHs): urinary 1-hydroxyprene glucuronide in relation to smoking and low ambient levels of exposure.

The study was conducted in a Chinese population with occupational or environmental exposures to polycyclic aromatic hydrocarbons (PAHs). A total of 106 subjects were recruited from coke-oven workers (workers), residents in a metropolitan area (residents) and suburban gardeners (gardeners). All subjects were monitored twice for their personal exposures to PAHs. The biological samples were collected for measurements of 1-hydroxypyrene (1-OHP) and cotinine in urine. The geometric means of personal exposure levels of pyrene, benz(a)anthracene (BaA) and benzo(a)pyrene (BaP) in workers were 1.470, 0.978 and 0.805 microg m-3, respectively. The corresponding levels in residents were 0.050, 0.034 and 0.025 microg m-3; and those in gardeners were 0.011, 0.020 and 0.008 microg m-3, respectively. The conjugate of 1-OHP with glucuronide (1-OHP-G) is the predominant form of pyrene metabolite in urine and it showed strong associations with exposures not only to pyrene, but also to BaA, BaP and total PAHs. Most importantly, a significant difference in 1-OHP-G was even detected between the subgroups with exposures to BaP at < 0.010 and > 0.010 but < 0.020 microg m-3, suggesting that 1-OHP-G is a good marker that can be used for the risk assessment of BaP exposure at levels currently encountered in ambient air. Furthermore, multiple regression analyses of 1-OHP-G on PAHs exposure indicated that cigarette smoke was a major confounding factor and should be considered and adjusted for while using 1-OHP to estimate PAHs exposure.     

Potential health effects of exposure to carcinogenic compounds in incense smoke in temple workers

Incense smoke is a potential hazard to human health due to various airborne carcinogens emitted from incense burning. This study aimed to evaluate the potential health effects of exposure to benzene, 1,3-butadiene, and polycyclic aromatic hydrocarbons (PAHs) emitted from incense smoke in temple workers. Exposure and health risks were assessed through the measurement of ambient exposure as well as through the use of biomarkers of exposure and early biological effects. Ambient air measurement showed that incense burning generates significantly higher levels of airborne benzene (P<0.01), 1,3-butadiene (P<0.001) and total PAHs (P<0.01) inside the temples, compared to those of the control workplace. Temple workers were exposed to relatively high levels of benzene (45.90 microg/m(3)) 1,3-butadiene (11.29 microg/m(3)) and PAHs (19.56 ng/m(3)), which were significantly higher than those of control workers (P<0.001). The most abundant PAHs were chrysene, B[ghi]P, B[a]P, B[a]F and fluoranthene. Concentrations of B[a]P and B[a]P equivalents in air samples to which temple workers were exposed were 63- and 16-fold, higher, respectively, than those to which control subjects were exposed (P<0.001). Biomarkers of exposure to benzene (blood benzene and the urinary metabolites trans,trans-muconic acid and S-phenylmercapturic acid), 1,3-butadiene (urinary monohydroxy-butenyl mercapturic acid) and PAHs (1-hydroxypyrene) were all significantly higher in temple workers than those in control workers. DNA damage and DNA repair capacity were measured as biomarkers of early biological effects. Temple workers had a significant increase in DNA damage observed as a 2-fold increase in the levels of leukocyte 8-hydroxy-2'-deoxguanosine (8-OHdG) and DNA strand breaks (P<0.001). A significant reduction of DNA repair capacity in temple workers determined by the radiation challenge assay was also observed. These results indicate that exposure to carcinogens emitted from incense burning may increase health risk for the development of cancer in temple workers.     

Lack of reversal effect of EDTA treatment on cadmium induced renal dysfunction: a fourteen-year follow-up

The aim of this study was to evaluate the effect of ethylenediaminetetraacetic acid (EDTA) on cadmium (Cd) induced renal dysfunction. Seventeen workers (14 males, 3 females) were diagnosed with occupational Cd poisoning in 1986. These individuals had between 7 to 39 years of Cd exposure. From 1986 to 1999, patients received periodic EDTA therapy as part of their follow-up, all at the same hospital. Levels of urinary cadmium (UCd) and urinary beta2-microglobulin (B2M) were measured before and after each annual EDTA treatment period. Renal dysfunction was defined as urinary B2M > 0.8 mg/g Cr (creatinine). In these workers, patients with UCd level higher than 10 microg/g Cr in 1986 had abnormal B2M excretions (> or = 0.8 mg/g Cr) or trended to have abnormal B2M levels during the treatment period. However, in subjects with UCd concentration lower than 10 microg/g Cr in 1986, their urinary B2M excretions either remained normal (< 0.8 mg/g Cr) or returned to normal during the treatment period. The prevalence of renal dysfunction increased during the follow up period regardless of whether UCd levels increased or not, indicating a progressive renal dysfunction despite removal from Cd exposure. Our results suggest that reversibility of renal dysfunction caused by Cd related to the level of Cd exposure at the time of removal from exposure: renal dysfunction could be reversed if initial UCd < 10 microg/g Cr, but was irreversible when UCd > 10 microg/g Cr. Repeated examinations on these 17 Cd exposed workers from 1986 to 1999 also revealed that periodic administration of EDTA had no beneficial effects on chronic Cd-induced renal dysfunction.     

Evaluation of environmental and biological monitoring methods for toluene exposure assessment in paint industry

The aim of this study was to assess the exposure to Toluene in paint industry and to evaluate the environmental and biological monitoring techniques for the assessment of occupational exposure to this aromatic hydrocarbon. In this study, personal active and passive air sampling for toluene measurements, blood and urine sampling respectively for B-Tol and HA or U-Tol analyses for eight workers from two paint and thinner production factories were collected during four successive working days. Correlations were analyzed between biological indicators and environmental toluene exposure levels.The concentration of Toluene measured in air samples ranged from 0.2 to 414.0 ppm (mean = 59.8 ppm), with high variability of atmospheric levels between activities and between days. No significant difference was found between airborne toluene concentrations measured by the two sampling methods. The correlation between air concentrations sampled by the diffusive sampling method and the biomarkers was the best for HA (r = 0.902, p < 0.01), followed by B-Tol (r = 0.820; p < 0.01), o-Cr (r = 0.691; p < 0.01) and U-Tol (r = 0.607; p < 0.05). The correlation was better between air concentrations and urinary metabolites HA and o-Cr for exposure levels higher than 50 ppm (r = 0.931; p < 0.01), and lower than 300 ppm (r = 0.827; p < 0.01), respectively.According to our results, workers in the studied industries are highly exposed to Toluene. Given the high correlation found between toluene concentrations in samples taken on dosimeters and those actively sampled on charcoal tubes, it may be assumed that both sampling methods are valuable. Despite the influencing factors, HA was found to be a reliable biological indicator for the monitoring of occupational exposure to toluene for high exposure levels. However, B-Tol seems to be an interesting alternative, since it is more specific and showed the best correlations with airborne toluene levels.     

Urinary and air biomonitoring of occupational exposure to benzene in oil pit workers

Abstract

The purpose of this study is to evaluate the personal exposure to benzene and its relationship with biomonitoring and quantitative risk assessment among the personnel working and living near oil pits. This study was conducted in one of oil subsidiary companies in Kharg in 2017. Airborne benzene exposure was evaluated over 8-h periods during work-shift by using personal active samplers. Urinary O-Cresol levels were determined using GC-FID for separation and detection. The highest mean concentration of airborne benzene was at monitoring location, A (0.53?ppm), monitoring location H (0.59?ppm) in the spring, monitoring location M (0.72?ppm) and monitoring location P (0.8?ppm) in the summer, which was more than suggested by the American Conference of Governmental Industrial Hygienists. No direct linear relationship was found between the concentration of airborne benzene, age, work experience, urinary creatinine, and O-Cresol in this study (p?>?.05). No significant difference was observed between urinary O-Cresol and benzene in occupational groups and different seasons (p?>?.05). The highest mean quantitative risk of cancers was observed in summer (1.21?±?0.47). According to the results of this study, urinary biomarker O-Cresol is not a suitable measure for evaluating exposure to environmental benzene.     

Domestic exposure to fungi and total serum IgE levels in asthmatic children

We measured the number of airborne, viable fungi and house dust mite (HDM) allergen levels in the homes of a group of asthmatic children. Blood samples were drawn and the amounts of total and specific serum IgE were determined. The association between the number of fungal colonies, dust mite allergen exposure, and specific and total IgE was evaluated. The number of viable airborne fungi was high (20,543 CFU/m(3)) in those investigated houses. Der p1 concentrations on child's mattress exceeding 2 microg/g were found in 78.6% of the houses. A quantitative dose-response relationship was demonstrated between the exposure to viable, airborne molds and the amount of total IgE (r = 0.4399 and P = .0249) and the level was further increased in children with coexposure to viable fungi and HDM.     

Evaluation of individually ventilated cage systems for laboratory rodents: occupational health aspects

New ventilated caging systems for laboratory animals were compared with conventional caging regarding allergen distribution, ergonomic suitability, cage environment and animal welfare. This paper presents occupational health evaluations. Mice were placed in individually ventilated cage (IVC) systems, a ventilated cabinet, and in cages on open shelves (conventional husbandry). The IVC systems were studied at negative and positive airflow. Aeroallergens were sampled on filters (n = 204, including controls) in undisturbed rooms and during cage changing. Concentrations of mouse urinary allergen (Mus m 1) in filter eluates were measured using sandwich ELISA. An ergonomic evaluation was performed with measurement of traction forces. Staff exposure during cage changing was high in all systems, range 116-4430 ng Mus m 1/m3. In undisturbed animal rooms, allergen levels were orders of magnitude higher when using conventional caging compared with ventilated systems; P < 0.001. At positive pressure both IVCs leaked allergen (median Mus m 1 concentration was < 0.08 ng/m3 at negative, but 6.5 ng/m3 (IVC1) and 0.8 ng/m3 (IVC2S) at positive pressure). The IVC systems had ergonomic disadvantages compared with the conventional husbandry and the ventilated cabinet, for instance with cages in unsuitable working heights. Ventilated husbandry solutions reduce levels of airborne allergen substantially at negative pressure, but are ergonomically less suitable. To prevent allergen exposure during cage changing, we propose that this procedure should be performed under ventilated conditions. Producers and users must cooperate in optimizing animal caging systems for both animals and staff.     

Comparative study of alanine-amino-peptidase and gamma-glutamyl-transferase activity in normal Wistar rat urine

24 h urinary alanine-amino-peptidase (AAP) and gamma-glutamyl transferase (GGT) activities were studied from the 3rd-7th month of life in male Wistar rats. A close relationship was found between AAP and GGT activity, except at the beginning and at the end of this period. At the end there appear 2 subgroups, the larger (70%) showing a strong correlation between AAP and GGT activity and the other (30%), demonstrating no correlation at all. A good correlation between AAP and GGT activities, creatinine, 24 h urine volume and 24 h creatinine output was found.     

Cobalt and antimony: genotoxicity and carcinogenicity

The purpose of this review is to summarise the data concerning genotoxicity and carcinogenicity of Co and Sb. Both metals have multiple industrial and/or therapeutical applications, depending on the considered species. Cobalt is used for the production of alloys and hard metal (cemented carbide), diamond polishing, drying agents, pigments and catalysts. Occupational exposure to cobalt may result in adverse health effects in different organs or tissues. Antimony trioxide is primarily used as a flame retardant in rubber, plastics, pigments, adhesives, textiles, and paper. Antimony potassium tartrate has been used worldwide as an anti-shistosomal drug. Pentavalent antimony compounds have been used for the treatment of leishmaniasis. Co(II) ions are genotoxic in vitro and in vivo, and carcinogenic in rodents. Co metal is genotoxic in vitro. Hard metal dust, of which occupational exposure is linked to an increased lung cancer risk, is proven to be genotoxic in vitro and in vivo. Possibly, production of active oxygen species and/or DNA repair inhibition are mechanisms involved. Given the recently provided proof for in vitro and in vivo genotoxic potential of hard metal dust, the mechanistic evidence of elevated production of active oxygen species and the epidemiological data on increased cancer risk, it may be advisable to consider the possibility of a new evaluation by IARC. Both trivalent and pentavalent antimony compounds are generally negative in non-mammalian genotoxicity tests, while mammalian test systems usually give positive results for Sb(III) and negative results for Sb(V) compounds. Assessment of the in vivo potential of Sb2O3 to induce chromosome aberrations (CA) gave conflicting results. Animal carcinogenicity data were concluded sufficient for Sb2O3 by IARC. Human carcinogenicity data is difficult to evaluate given the frequent co-exposure to arsenic. Possible mechanisms of action, including potential to produce active oxygen species and to interfere with DNA repair systems, still need further investigation.     

Urinary biomarkers of 1,3-butadiene in environmental settings using liquid chromatography isotope dilution tandem mass spectrometry

Although, 1,3-butadiene is a known human carcinogen emitted from mobile sources, little is known about traffic-related human exposure to this toxicant. This pilot study was designed to characterize traffic-related environmental exposure to 1,3-butadiene and evaluate its urinary mercapturic acids as biomarkers of exposure in these settings. Personal air samples and multiple urine samples were collected on two separate occasions from three groups of individuals that differed by spatial proximity as well as intensity of traffic: (i) toll collectors, (ii) urban-weekday and (iii) suburban-weekend group. Air samples were analyzed using thermal desorption followed by GC/MS and urine samples were analyzed using isotope dilution liquid chromatography tandem mass spectrometry (ID-LC-MS/MS) for two mercapturic acids of 1,3-butadiene: monohydroxy-3-butenyl mercapturic acid (MHBMA) and 1,2-dihydroxybutyl mercapturic acid (DHBMA). Exposure differed between groups (p<0.05) with median values of 2.38, 1.62 and 0.88 microg/m(3) for toll collectors, the urban-weekday group and the suburban-weekend group, respectively. A refined ID-LC-MS/MS method enabled detection of MHBMA, previously detected only in occupational settings, with high frequency. MHBMA and DHBMA were detected in 95 and 100% of urine samples at levels (mean+/-S.D.) of 9.7+/-9.5, 6.0+/-4.3 and 6.8+/-2.6 ng/mL for MHBMA and 378+/-196, 258+/-133 and 306+/-242 ng/mL for DHBMA for the three different groups, respectively. Mean biomarker levels were higher among the toll collectors compared to the other two groups, however, the differences were not statistically significant (p>0.05). This study is the first to evaluate 1,3-butadiene biomarkers for subtle differences in environmental exposures. However, additional research will be required to ascertain whether the lack of statistical association observed here is real or attributable to unexpectedly small differences in exposure between groups (<1 microg/m(3)), non-specificity of the biomarker at low exposure, and/or small sample size.     

Individual exposure to NO2 in relation to spatial and temporal exposure indices in Stockholm, Sweden: the INDEX study

Epidemiology studies of health effects from air pollution, as well as impact assessments, typically rely on ambient monitoring data or modelled residential levels. The relationship between these and personal exposure is not clear. To investigate personal exposure to NO(2) and its relationship with other exposure metrics and time-activity patterns in a randomly selected sample of healthy working adults (20-59 years) living and working in Stockholm. Personal exposure to NO(2) was measured with diffusive samplers in sample of 247 individuals. The 7-day average personal exposure was 14.3 μg/m(3) and 12.5 μg/m(3) for the study population and the inhabitants of Stockholm County, respectively. The personal exposure was significantly lower than the urban background level (20.3 μg/m(3)). In the univariate analyses the most influential determinants of individual exposure were long-term high-resolution dispersion-modelled levels of NO(2) outdoors at home and work, and concurrent NO(2) levels measured at a rural location, difference between those measured at an urban background and rural location and difference between those measured in busy street and at an urban background location, explaining 20, 16, 1, 2 and 4% (R(2)) of the 7-day personal NO(2) variation, respectively. A regression model including these variables explained 38% of the variation in personal NO(2) exposure. We found a small improvement by adding time-activity variables to the latter model (R(2)?=?0.44). The results adds credibility primarily to long-term epidemiology studies that utilise long-term indices of NO(2) exposure at home or work, but also indicates that such studies may still suffer from exposure misclassification and dilution of any true effects. In contrast, urban background levels of NO(2) are poorly related to individual exposure.     

Biological monitoring of exposure to sevoflurane in operating room personnel by the measurement of hexafluoroisopropanol and fluoride in urine

The objectives of this study were to evaluate the value of urinary hexafluoroisopropanol (HFIP) and fluoride (F^-) measurement for the biological monitoring of operating room personnel exposed to sevoflurane. Fifty members of operating room staffs from eight different hospitals took part in the study. To assess external exposure to sevoflurane, air samples were collected during the whole anaesthesia period by a passive sampling device (3M 3500 organic vapour monitor) attached close to the breathing zone of each subject. Urine was collected before (BA) and at the end of anaesthesia (EA) for the determination of HFIP, fluoride and creatinine. Average airborne concentration of sevoflurane was 19.0 ppm (range: ND-139.9 ppm) with a mean duration of anaesthesia of 221 min (range: 60-435 min). There was a better correlation between external and internal exposure as estimated by EA urinary HFIP (r = 0.78; p &lt;0.0001) compared with EA urinary F^- (r = 0.41; p = 0.0031). Furthermore determination of urinary HFIP seemed more suited than that of F^- for the assessment of sevoflurane exposure because of lower background in BA samples (86 % of BA HFIP values were under the limit of detection). Based on these results, values of 9.6 and 4.3 mg HFIP g^-1 creatinine correspond to airborne concentrations of 50 and 20 ppm of sevoflurane, respectively. Among the confounding parameters investigated (body mass index (BMI), sex, cytochrome P450 polymorphism) only BMI showed statistically significant influence on sevoflurane metabolism at these low levels of exposure. The measurement of HFIP in urine at the end of the surgical procedure constitutes a good index to assess occupational exposure to sevoflurane. Further studies will be necessary to propose an health-based limit value which remains to be determined from the relationship between effects and internal dose as can be assessed by HFIP measurement in urine.     

PAH-DNA adducts in a Chinese population: relationship to PAH exposure, smoking and polymorphisms of metabolic and DNA repair genes.

The present study was conducted in a Chinese population to evaluate the usefulness and sensitivity of PAH-DNA adduct as a biomarker of PAH exposure, and to examine the potential effects of smoking and polymorphisms of responsive genes on DNA adduct formation induced by PAH exposure. The polymorphisms of genes examined include GSTM1, GSTT1, CYP1A1, microsomal epoxide hydrolase (mEH) and excision repair cross-complementary group 2 (ERCC2). A total of 194 subjects with a broad range of PAH exposures were recruited, including 116 occupationally exposed workers, 49 metropolitan residents and 29 suburban gardeners. A significant exposure-response relationship was observed between PAH exposure and DNA adducts in leukocytes across the entire group of subjects (p < 0.0001). The levels of PAH-DNA adducts in the subgroup with lowest occupational exposure to PAHs (< 0.1 microg BaP m(-3)) was significantly higher than that in metropolitan residents and suburban gardeners. However, no significant difference was detected between residents and gardeners, with mean BaP concentrations of 0.028 and 0.011 microg m(-3), respectively. The polymorphisms of genes examined failed to show significant effects on PAH-induced adduct formation except ERCC2 Lys751Gln genotypes. A significantly higher level of PAH-DNA adduct was found in subjects with wild-type ERCC2 than those who have either heterozygous or homozygous variant alleles (p < 0.01). Smoking, age and gender did not substantially contribute to PAH-induced DNA adduct formation in this study. The study suggests that PAH-DNA adducts may serve as a reliable biomarker of PAH exposure in occupational settings but may not be sensitive enough to be used in populations with environmental exposures to PAHs.     

Airborne contaminants in conventional laboratory rabbit rooms

Besides the well known allergens, several other risk factors may exist for health in a laboratory animal unit. The exposure to these factors may be significant in animal units with poor general or local ventilation systems. Moreover, means to prevent the distribution of airborne contaminants may be limited in animal units housing rabbits or other bigger laboratory animals. Airborne contaminants in conventional laboratory rabbit rooms were sought to evaluate the occupational exposure of animal care personnel. Concentrations of airborne dust, bacteria, fungi, ammonia and endotoxins were measured during 2 days in three phases: before working activities began, during them and afterwards. Both stationary and some personal samples were taken. All of the contaminants sought were found in the rabbit room air. When compared to reported levels in farm animal production areas, the concentrations measured were generally low. However, moderate or high levels of airborne bacteria and fungi were found occasionally during work routines. Airborne contaminants should be considered as a potential occupational health risk for persons working with laboratory animals.     

Estimating occupational exposure to the pyrethroid termiticide bifenthrin by measuring metabolites in urine

The control of subterranean termites in Australia is predominantly through the application of chemical barriers in the soil beneath and surrounding buildings. The chemicals used to repel or kill termites are the organophosphorus insecticide, chlorpyrifos, and the synthetic pyrethroid, bifenthrin. These are applied through surface sprays and subfloor injection by licensed pest control operators. To determine the exposure of these personnel to these pesticides it is most usual to measure airborne concentrations or dermal deposition rates. However, to support information obtained from these methods it is often appropriate to determine the amount of the chemicals absorbed, using biological monitoring techniques including measurement of the chemicals or their metabolites in urine. While there are effective techniques for the monitoring of chlorpyrifos exposure by measuring either the alkyl phosphate or trichloropyridinol metabolites, there have been no published reports of suitable methods to measure bifenthrin metabolites in urine. This paper describes an extraction and HPLC-UV method used to simultaneously measure the urinary excretion of 2-methyl-3-phenylbenzoic acid (MPA), a metabolite of bifenthrin, and 3-phenoxybenzoic acid (PBA), a metabolite of several other common pyrethroid insecticides, with a detection limit for each of 2.5 ng/ml. The paper also describes the pilot application of this method to a study of South Australian pest control operators handling bifenthrin. MPA ranged from 1.8 to 31.9 microg/g creatinine and PBA from 1.3 to 30.0 microg/g in the urine of pest control workers. MPA was detected in urine of control workers without bifenthrin exposure only at low levels (1.0-1.4 microg/g creatinine), but PBA was found in both at higher levels (1.2-61.1 microg/g creatinine).     

Biomarkers of exposure to aromatic hydrocarbons and methyl tert-butyl ether in petrol station workers

This cross-sectional study was aimed at reconstructing the exposure to gasoline in 102 petrol station attendants by environmental and biological monitoring of benzene, toluene, ethylbenzene and xylene (BTEX) and biomonitoring of methyl tert-butyl ether (MTBE). Airborne BTEX were higher for manual refuelers than self-service assistants and were highly correlated with each other. Significant relationships were found between airborne BTX and the corresponding urinary solvents (U-BTX) and beween airborne B and urinary MTBE (U-MTBE). Smokers eliminated higher values of U-B, trans,trans-muconic (t,t-MA) and S-phenylmercapturic (S-PMA) acids but not U-MTBE. All these biomarkers were, however, significantly raised during the shift, independently from smoking. Linear regression confirmed that occupational exposure was a main predictor of U-MTBE, U-B and S-PMA values, both the latter confounded by smoking habits. The study supports the usefulness of biomonitoring even at low exposure levels.     

Field Evaluation of Personal Sampling Methods for Multiple Bioaerosols

Ambient bioaerosols are ubiquitous in the daily environment and can affect health in various ways. However, few studies have been conducted to comprehensively evaluate personal bioaerosol exposure in occupational and indoor environments because of the complex composition of bioaerosols and the lack of standardized sampling/analysis methods. We conducted a study to determine the most efficient collection/analysis method for the personal exposure assessment of multiple bioaerosols. The sampling efficiencies of three filters and four samplers were compared. According to our results, polycarbonate (PC) filters had the highest relative efficiency, particularly for bacteria. Side-by-side sampling was conducted to evaluate the three filter samplers (with PC filters) and the NIOSH Personal Bioaerosol Cyclone Sampler. According to the results, the Button Aerosol Sampler and the IOM Inhalable Dust Sampler had the highest relative efficiencies for fungi and bacteria, followed by the NIOSH sampler. Personal sampling was performed in a pig farm to assess occupational bioaerosol exposure and to evaluate the sampling/analysis methods. The Button and IOM samplers yielded a similar performance for personal bioaerosol sampling at the pig farm. However, the Button sampler is more likely to be clogged at high airborne dust concentrations because of its higher flow rate (4 L/min). Therefore, the IOM sampler is a more appropriate choice for performing personal sampling in environments with high dust levels. In summary, the Button and IOM samplers with PC filters are efficient sampling/analysis methods for the personal exposure assessment of multiple bioaerosols.     

Measuring personal exposure to airborne mutagens and nicotine in environmental tobacco smoke

The exposure of individuals to environmental tobacco smoke (ETS) is of increasing public health concern because epidemiological studies have associated passive smoking with increased risk of a variety of adverse health effects among non-smokers including lung cancer. As a way to measure individual exposure to the mutagenic compounds in the complex mixture of ETS, we used a sensitive Salmonella/microsome micro pre-incubation (microsuspension) assay to detect mutagenicity of particulate matter collected on filters from low volume (1.7 1/min flow rate) personal sampling pumps. Airborne nicotine was collected concurrently as a marker for ETS exposure. In pilot-field studies, individual exposure to ETS was measured in two separate indoor environments in which smokers were present: a gambling casino and a bingo parlor. Total suspended particulate matter (TSP) was collected on filters worn near the breathing zone of non-smoking individuals. Sampling times ranged from 40 min to 6 h. All extracts of filters had detectable levels of mutagenic activity (TA98, +S9) resulting in airborne mutagenic activity concentrations of 500-5000 rev/m3. The mutagenic activity of the filters from the casino and bingo parlors was significantly correlated with total particulate matter per filters (n = 12; Rho = 0.85, p less than 0.01) and with airborne nicotine per filter (n = 12; Rho = 0.95, p less than 0.01). The microsuspension assay was sufficiently sensitive to detect the mutagens associated with extracts of particulate matter from low volume samples (0.2-0.6 m3) in these indoor environments over a relatively short sampling time, and could be useful in studies of personal exposure to the mutagens in environmental tobacco smoke. Further, airborne nicotine concentrations were highly correlated with airborne mutagenicity and the mutagenic activity associated with ETS could therefore be estimated by the concentrations of nicotine.