A study on the effectiveness of training in the operation of an electric mobility aid in severely mentally and physically handicapped children.

Hideshima Y, Asami T, Ichiba M, Matsuo K, Murata T. A study on the effectiveness of training in the operation of an electric mobility aid in severely mentally and physically handicapped children. Jpn J Compr Rehabil Sci 2024; 15: 8-16. Purpose: We examined whether operation training for children with severe mental and physical disabilities using recently developed electric mobility aids improves their skills in operating such aids and their daily activities. By doing so, we aimed to clarify the effectiveness of electric mobility aid operation training for children with severe mental and physical disabilities. Method: Operation training and normal training using an electric mobility aid were conducted for 42 school-aged children with severe mental and physical disabilities, aged 8-18 years old. The trainee children were randomly assigned to two groups: 21 to the intervention group to receive operation training and 21 to the control group to receive general training. The intervention lasted 20 minutes/training session, with three sessions/week over a period of eight weeks. The Powered Mobility Program (PMP) and Pediatric Evaluation of Disability Inventory (PEDI) were used for pre- and post-intervention assessments, and SPSS was used for two-way analysis of variance (ANOVA). Results: PMP scaled scores significantly increased (p = 0.001) in both groups, but there was no interaction effect. The PEDI scaled scores did not significantly increase in either of the two groups. Discussion: The effects of the intervention and use of the electric mobility aid on the operating skills of children with severe mental and physical disabilities were explicitly demonstrated. Future long-term studies are required to clarify the effects of training in the operation of electric mobility aids on the subsequent development of severely physically and mentally handicapped children.

Assessment of dermal exposure to N,N-dimethylacetamide in spray workers by combining personal exposure monitoring, biological monitoring, and glove permeation monitoring: A pilot study.

OBJECTIVES: We assessed dermal exposure to N,N-dimethylacetamide (DMAC) in a spray worker by utilizing a combination of personal exposure monitoring, biological monitoring, and glove permeation monitoring. We also determined the protective effects of chemical protective gloves (CPGs). METHODS: Surveys with and without CPG usage were performed on different days. In the survey with CPG usage, the worker had worn leather gloves over the CPG. Personal exposure monitoring and glove permeation monitoring were performed using 3M Organic Vapor Monitor 3500 and PERMEA-TEC Pads respectively. Urinary concentration of DMAC and its metabolites (N-methylacetamide [NMAC], N-hydroxymethyl-N-methylacetamide [DMAC-OH], S-(acetamidomethyl) mercapturic acid [AMMA]) were measured in the before-shift and end-of-shift samples collected from the worker. RESULTS: Personal exposure DMAC concentration in the survey with CPG usage (0.32 ppm) was twice that in the survey without CPG usage (0.15 ppm). However, urinary concentrations of DMAC-OH and AMMA in the end-of-shift samples in the survey with CPG usage (DMAC-OH, 0.74 mg/g creatinine; AMMA, 0.10 mg/g creatinine) were lower than those in the survey without CPG usage (DMAC-OH, 1.27 mg/g creatinine; AMMA, 0.24 mg/g creatinine). Urinary concentrations of DMAC and NMAC were below the limit of detection in all samples. DMAC concentrations in PERMEA-TEC Pads that were used in the surveys with and without CPG usage were in the range of 0.3-2.1 µg/sample and 16.4-1985.2 µg/sample respectively. CONCLUSIONS: The combination of CPG usage and leather gloves was effective in preventing dermal exposure to DMAC.

Evaluation of the ceiling levels of ortho-phthalaldehyde exposure among health care workers engaged in endoscope disinfection: A new methodology using video-exposure monitoring.

OBJECTIVES: The present study aimed to develop a method for measuring the ceiling level of ortho-phthalaldehyde (OPA) exposure and evaluate the ceiling levels of OPA exposure among health care workers who handle disinfectant solutions containing OPA for the disinfection of endoscopes. METHODS: The study consisted of a preliminary survey and main survey. In the preliminary survey, processes involving high-concentration exposure to OPA were identified by video-exposure monitoring (VEM). In the main survey, the ceiling levels of OPA exposure for high-concentration exposure processes identified from the results of the preliminary survey were determined using a measuring method combining sampling using a 2,4-dinitrophenylhydrazine-silica cartridge and analysis by high-performance liquid chromatography tandem mass spectrometry. RESULTS: In the preliminary survey, seven processes involving high-concentration exposure to OPA were identified by VEM. The duration of each process was short, lasting from 20 seconds to a few minutes. In the main survey, the OPA concentrations for the identified high-concentration exposure processes ranged from 1.18 to 4.49 ppb, which markedly exceeded the threshold limit value ceiling (TLV-C) of 0.1 ppb recommended by the American Conference of Governmental Industrial Hygienists. CONCLUSIONS: The method for measuring the ceiling level of OPA exposure was established using VEM and the highly sensitive method of chemical analysis; and we successfully evaluated the ceiling levels of OPA exposure among health care workers engaged in endoscope disinfection. This approach can also be applied to other chemical substances with recommended TLV-Cs, and important information for reducing exposure can thus be obtained.

Development of a measurement method to determine the ceiling exposure concentration of ortho-phthalaldehyde handling workers.

OBJECTIVES: The purpose of this research was to develop and validate an analytical method for rapid determination of the exposure of workers to ortho-phthalaldehyde (OPA) at the ceiling threshold concentration. METHODS: A 2,4-dinitrophenylhydrazine (DNPH)-silica cartridge was chosen as a sampler. OPA collected by the DNPH-silica cartridge was subsequently extracted with 5 mL of acetonitrile. A 50-µL aliquot of phosphoric acid/acetonitrile solution (2%, v/v) was added to 950 µL of the extraction solution and allowed to stand for 30 minutes at room temperature. This solution was then analyzed by high-performance liquid chromatography tandem mass spectrometry. The basic characteristics of the proposed method, such as recovery, repeatability, limit of quantification, and storage stability of the samples, were examined. RESULTS: The overall recoveries of OPA from OPA-spiked DNPH-silica cartridges were 93.6%-100.1% with relative standard deviations, representing the repeatability, of 1.5%-10.8%. The limit of quantification was 0.165 ng/sample. The recovery of OPA from DNPH-silica cartridges after 5 days of storage in a refrigerator exceeded 95%. CONCLUSIONS: The proposed method enabled the determination of the OPA concentration corresponding to the Threshold Limit Value-Ceiling of 0.1 ppb recommended by the American Conference of Governmental Industrial Hygienists, with a minimum sampling time of 18 seconds (corresponding to a sampling volume of 300 mL at 25°C and 1 atm). Thus, this method will be useful for estimating worker exposures to OPA.

Particular protrusion perception arising from plantar sensory input and task guidance enhances lower limb joint dynamics during gait.

[Purpose] To assess the influence of plantar sensory input and task guidance produced by a protrusion on lower limb joint dynamics during gait by changes in muscle activity and two-dimensional motion analysis. The protrusion seals on the soles of the feet, named "Perceptual Stimulus Protrusion" were used in this study. [Participants and Methods] In this study, 40 and 42 healthy adults were recruited for muscle activity and two-dimensional analysis, respectively. In addition to walking without perceptual stimulus protrusion ("Control" condition), the testing conditions included attachment of the protrusion to the heel ("Heel Condition") and the hallucal ("Hallucal Condition"). As task guidance, participants were orally instructed how to walk for each conditions. The muscle activities of the rectus femoris, vastus medialis, tibialis anterior, and medial head of the gastrocnemius were measured. The two-dimensional analysis was compared with the angle of ankle dorsiflexion and plantarflexion, the toe height during the swing phase between the test conditions, respectively. [Results] In the Heel Condition, the tibialis anterior and vastus medialis activity in the stance and swing phases, toe height, and angle of ankle dorsiflexion and plantarflexion increased. In the Hallucal Condition, tibialis anterior activity during the stance and swing phases, gastrocnemius activity during the stance phase, toe height, and angle of ankle plantarflexion increased. [Conclusion] Plantar sensory input and task guidance using perceptual stimulus protrusion influences active motion control. Therefore, the application of this procedure can be expected to support motion guidance, such as gait and load practice.

Ethanol induces skin hyperpigmentation in mice with aldehyde dehydrogenase 2 deficiency.

Alcohol induces various cutaneous changes, such as palmar erythema and jaundice. However, alcohol-induced skin hyperpigmentation due to melanin deposition has not been reported. Aldehyde dehydrogenase 2 (ALDH2), one of 19 human ALDH isozymes, metabolizes endogenous and exogenous aldehydes to their respective carboxylic acids. Reduced ALDH2 greatly affects acetaldehyde metabolism, leading to its accumulation in the body after the consumption of alcohol and the consequent development of a wide range of phenotypes. In the present study, we report a novel phenotype manifesting in a mouse model with the altered expression of ALDH2. Aldh2 knockout (Aldh2+/- and Aldh2-/-) and wild-type (Aldh2+/+) mice were fed a standard solid rodent chow and a bottle of ethanol solution at concentrations of 0%, 3%, 10%, or 20% (v/v) for more than 10 weeks. The intensity of their skin pigmentation was evaluated by macroscopic observation. Ethanol-exposed Aldh2+/- and Aldh2-/- mice exhibited dose-dependent skin pigmentation in areas of hairless skin, including the soles of the paws and tail; no such changes were observed in wild-type mice. The intensity of skin pigmentation correlated with the number of Aldh2 alleles that were altered in the mice (i.e., 0, 1 and 2 for Aldh2+/+, Aldh2+/-, Aldh2-/-, respectively). Interestingly, the skin pigmentation changes reversed upon the discontinuation of ethanol. The histological examination of the pigmented skin demonstrated the presence of melanin-like deposits, mainly in the epidermis. In conclusion, we report a novel finding that the intake of ethanol induces skin hyperpigmentation in an ALDH2 activity-dependent manner.

Effect of limbering up of the muscles attached to the pelvis on the strength of upper and lower extremity and trunk muscles through the transitional network.

[Purpose] To study the effect that limbering up of the muscles attached to the pelvis has on muscle strength of the trunk and upper and lower extremities, which are not being exercised, and to investigate the possibilities for clinical application. [Subjects and Methods] A total of 152 healthy adult men. Sthenometry was conducted using a handheld dynamometer to assess the effect of limbering up of the upper gluteus maximus, hamstrings, and internal abdominal oblique muscles attached to thoracolumbar fascia on the trunk and upper and lower extremities. The exercises were slowly performed 20 repetitions. Subjects were divided into AB group (n=49) measuring abdominal and back muscle strength, K group (n=42) measuring knee flexor and extensor strength, and S group (n=61) measuring shoulder flexor and external rotator strength and compared to non-exercising controls. [Results] In the exercise groups, exercising either gluteus maximus or hamstrings significantly increased the strength of abdominal and back muscles; exercising gluteus maximus increased knee extensor strength, and exercising the abdominal internal oblique muscle significantly increased knee flexor strength; and shoulder flexor strength significantly increased after exercising gluteus maximus versus controls. [Conclusion] This may be useful in rehabilitation of injuries to the trunk and upper and lower extremities.

Variability and reliability of POP concentrations in multiple breast milk samples collected from the same mothers.

Risk assessment of infant using a realistic persistent organic pollutant (POP) exposure through breast milk is essential to devise future regulation of POPs. However, recent investigations have demonstrated that POP levels in breast milk collected from the same mother showed a wide range of variation daily and monthly. To estimate the appropriate sample size of breast milk from the same mother to obtain reliable POP concentrations, breast milk samples were collected from five mothers living in Japan from 2006 to 2012. Milk samples from each mother were collected 3 to 6 times a day through 3 to 7 days consecutively. Food samples as the duplicated method were collected from two mothers during the period of breast milk sample collection. Those were employed for POP (PCBs, DDTs, chlordanes, and HCB) analysis. PCB concentrations detected in breast milk samples showed a wide range of variation which was maximum 63 and 60% of relative standard deviation (RSD) in lipid and wet weight basis, respectively. The time course trend of those variations among the mothers did not show any typical pattern. A larger amount of PCB intake through food seemed to affect 10 h after those concentrations in breast milk in lipid weight basis. Intraclass correlation coefficient (ICC) analyses indicated that the appropriate sample size for good reproducibility of POP concentrations in breast milk required at least two samples for lipid and wet weight basis.

Concentration determination of urinary metabolites of N,N-dimethylacetamide by high-performance liquid chromatography-tandem mass spectrometry.

OBJECTIVES: N,N-Dimethylacetamide (DMAC) is widely used in industry as a solvent. It can be absorbed through human skin. Therefore, it is necessary to determine exposure to DMAC via biological monitoring. However, the precision of traditional gas chromatography (GC) is low due to the thermal decomposition of metabolites in the high-temperature GC injection port. To overcome this problem, we have developed a new method for the simultaneous separation and quantification of urinary DMAC metabolites using liquid chromatography-tandem mass spectrometry (LC-MS/MS). METHODS: Urine samples were diluted 10-fold in formic acid, and 1-µl aliquots were injected into the LC-MS/MS equipment. A C18 reverse-phase Octa Decyl Silyl (ODS) column was used as the analytical column, and the mobile phase consisted of a mixture of methanol and aqueous formic acid solution. RESULTS: Urinary concentrations of DMAC and its known metabolites (N-hydroxymethyl-N-methylacetamide (DMAC-OH), N-methylacetamide (NMAC), and S- (acetamidomethyl) mercapturic acid (AMMA) ) were determined in a single run. The dynamic ranges of the calibration curves were 0.05-5 mg/l (r≥0.999) for all four compounds. The limits of detection for DMAC, DMAC-OH, NMAC, and AMMA in urine were 0.04, 0.02, 0.05, and 0.02 mg/l, respectively. Within-run accuracies were 96.5%-109.6% with relative standard deviations of precision being 3.43%-10.31%. CONCLUSIONS: The results demonstrated that the proposed method could successfully quantify low concentrations of DMAC and its metabolites with high precision. Hence, this method is useful for evaluating DMAC exposure. In addition, this method can be used to examine metabolite behaviors in human bodies after exposure and to select appropriate biomarkers.

Development of suitable method for large-scale urinary glucocorticoid analysis by liquid chromatography-mass spectrometry.

Levels of urinary glucocorticoids and their concentration ratios have been analyzed as potential markers for various pathological statuses. Large-scale studies may possibly accelerate the investigations; however, a suitable method needs to be established. Analytical conditions for measurement of urinary glucocorticoids with LCMS were examined. Electrospray ionization in the positive ion mode was applied for detection of cortisol (precursor>product ion: 363.3>121.0), cortisol-d4 (internal standard, IS, 367.4>121.1), and cortisone (361.2>163.2). To maximize ionization, acetic acid-ammonium acetate buffer (18mM) at pH 5.3 was employed as eluent A. A C18 column (100mm×2.1mm, 2.7µm) at 50°C was used for the 9.5min binary gradient separation starting with 60% eluent A with methanol being eluent B. Linear correlations were observed between the concentrations and the peak areas in the concentration range of 1-300ng/mL with correlation coefficients (r) of 0.998 and 0.997 for cortisol and cortisone, respectively, without IS adjustment, and 0.999 with IS adjustment for both cortisol and cortisone. Solid-phase extraction (SPE) using a 2mL centrifuge column was performed for the urine samples, with the original and final volumes being 100µL. The SPE of 12 urine specimens could be performed within 30min. The effect of the sample matrix on the quantification of endogenous compounds present in the urine extract was limited (coefficient of variation (CV) of IS-adjusted matrix factor: 4.4-8.1%; urine extracts of 8 individuals); however, substantial peak reduction of cortisol was observed at low concentrations. Exogenous contaminants originating from the SPE centrifuge column seemed to be a main cause for this phenomenon because the pure-water extract showed similar peak reduction. A recovery of ∼50% was obtained for both cortisol and cortisone. Adjustment with the IS improved the apparent recovery, with ∼100% being obtained for both cortisol and cortisone. The recovery rate decreased when the urine samples were concentrated in the SPE step; the reduction was greater for cortisol than for cortisone. The lower limit of quantification (LLOQ) was set at 2.5ng/mL when the injection volume was 10µL, based on the reproducibility of the standards which were measured (CV of 12 repetitions: 10.1% for 0.5ng/mL cortisol and 19.6% for 1ng/mL cortisone), the matrix effect (-55% at 2ng/mL concentrations of cortisol), and the recovery rate (∼50%). Furthermore an alternative approach for preparation of the cortisol standards was required for low concentration range (2.5-20ng/mL) because of the effect of the matrix. Degradation of original urine specimens at room temperature was minimal during the first 24h. The extracted urine samples degraded over time; however, their concentrations were corrected with the IS, allowing for analysis up to 5days after extraction. In conclusion, an analytical method for urinary glucocorticoids was established, which is fast, sensitive, and well suited for practical application to large-scale study.

Heme oxygenase 1 protects ethanol-administered liver tissue in Aldh2 knockout mice.

A genetic polymorphism of the aldehyde dehydrogenase 2 (​ALDH2) gene, ALDH2*2, encodes an enzymatically defective ALDH2 protein. Recent epidemiological studies suggest that possessing ALDH2*2 is a protective factor for liver tissue in healthy individuals, although these studies lack a mechanistic explanation. Our animal studies have shown the same trend: levels of serum alanine transaminase (ALT), hepatic malondialdehyde (MDA), and hepatic tumor necrosis factor alpha (TNF-α) were lower in Aldh2 knockout (Aldh2(-/-)) mice than in wild-type (Aldh2(+/+)) mice after ethanol administration. To propose a mechanistic hypothesis, residual liver specimens from the previous experiment were analyzed. An anti-oxidative protein, heme oxygenase 1 (HO-1), and an oxidative stress-producing protein, cytochrome P450 2E1 (CYP2E1), were detected at higher levels in Aldh2(-/-) mice than in Aldh2(+/+) mice, regardless of ethanol treatment. Other oxidative stress-related proteins and inflammatory cytokines did not show such a significant difference. To conclude, we propose a protective role of HO-1 in individuals with A​LDH2*2. Our continued studies support the epidemiological finding that possession of ALDH2*2 is a protective factor in the liver of the healthy individual.

Does antihypertensive treatment with renin-angiotensin system inhibitors prevent the development of diabetic kidney disease?

BACKGROUND: Diabetic kidney disease (DKD) is the leading cause of end-stage renal disease worldwide. Renin-angiotensin system (RAS) inhibitors are the first-line treatment for diabetic patients with hypertension. However, whether RAS inhibitors prevent the development of DKD remains controversial. We conducted a retrospective cohort study quantifying the preventive effect of antihypertensive treatment with RAS inhibitors on DKD, using data from specific health check-ups and health insurance claims. METHODS: The study subjects were 418 patients with diabetes and hypertension, drawn from health insurance societies located in Fukuoka and Shizuoka prefectures in Japan. The subjects were divided into three groups, according to the type of antihypertensive treatment they received. They were then compared in terms of the development of DKD, using the diagnostic codes from ICD-10. RESULTS: Thirty subjects (6.2%) developed DKD during the study period between April 2011 and September 2013. RAS inhibitor treated group showed a significantly lower risk of DKD [adjusted odds ratio (AOR) = 0.35; 95% confidential interval (CI): 0.16-0.76] compared with the no treatment group. CONCLUSION: We conclude that antihypertensive treatment with RAS inhibitors is potentially useful for preventing the development of DKD.

Exposure assessment of organophosphorus and organobromine flame retardants via indoor dust from elementary schools and domestic houses.

To assess the exposure of flame retardants (FRs) for school-children, organophosphorus flame retardants and plasticizers (PFRs) and organobromine flame retardants (BFRs) were determined in the indoor dust samples collected from elementary schools and domestic houses in Japan in 2009 and 2010. PFRs were detected in all the dust samples analyzed and the highest concentration of total PFRs was thousand-fold higher than that of BFRs. Among the PFRs, tris(butoxyethyl)phosphate (TBOEP) showed the highest concentration with a median (med.) of 270,000 ng g(-1) dry weight (3700-5,500,000 ng g(-1) dry weight), followed by tris(methylphenyl)phosphate (TMPPs)>triphenyl phosphate (TPHP)=tris(1,3-dichloro-2-propyl)phosphate (TDCIPP)=tris(2-chloroisopropyl)phosphate (TCIPP)=tris(2chloroethyl)phosphate (TCEP)>ethylhexyl diphenyl phosphate (EHDPP). Significantly higher concentrations of TBOEP, tri-n-butyl phosphate (TNBP), TPHP, TMPPs, and total-PFRs were found in dust samples from elementary schools than from domestic houses. It might be due to that higher concentrations of TBOEP (as leveling agent) were detected from the floor polisher/wax products collected in those elementary schools. On the other hand, significantly higher concentrations of TCEP, TCIPPs, and total chloroalkyl-PFRs were found in domestic houses than in elementary schools. Exposure assessments of PFRs via indoor dust from elementary schools and domestic houses were conducted by calculating the hazard quotient (HQ). Among PFRs, HQs for TBOEP exceeded 1 (higher than reference dose: RfD) and its highest value was 1.9. To reduce the intake of TBOEP by school-children, it is recommended that the use of floor polisher/wax containing TBOEP be reduced in schools.

Ethanol reduces lifespan, body weight, and serum alanine aminotransferase level of aldehyde dehydrogenase 2 knockout mouse.

BACKGROUND: The aldehyde dehydrogenase 2 (Aldh2) knockout mouse is an animal model of a polymorphism at the human ALDH2 locus (ALDH2*2). To detect differences in the basic phenotype of this animal model, lifespan, body weight (BW), and serum alanine aminotransferase (ALT) level were evaluated. METHODS: Aldh2(+/+) , Aldh2(+/-) , and Aldh2(-/-) mice were maintained, from 10 weeks of age, on standard solid food, with liquid supplied as ethanol (EtOH) solution at a concentration of 0 to 20% (forced EtOH consumption). RESULTS: For animals provided with water (without EtOH), mice of the distinct genotypes exhibited no difference in lifespan, with the mean values ranging from 90 to 96 weeks for female mice and 97 to 105 weeks for male mice. For animals provided with EtOH, there was a dose-dependent reduction of lifespan in Aldh2(-/-) mice with p for trend <0.001. For example, the mean lifespans of the Aldh2(-/-) females in the 0, 3, 10, and 20% groups were 95, 85, 70, and 29 weeks, respectively. No influence on lifespan was found for Aldh2(+/+) and Aldh2(+/-) mice. BW and ALT level of Aldh2(-/-) mice were significantly lower than those of Aldh2(+/+) mice when the mice were treated with EtOH. While multiple regression analysis suggested that the BW and ALT level in Aldh2(-/-) mice correlated with lifespan, adjustment for EtOH concentration revealed that this correlation was not significant (i.e., reflected EtOH dependence). CONCLUSIONS: Aldh2(-/-) mice were unchanged in terms of their basic phenotype under standard laboratory conditions. However, chronic EtOH administration (forced consumption) in these mice resulted in dose-dependent reductions in lifespan, BW, and serum ALT level.

Applicability of concentrations obtained by working environment measurement to assessment of personal exposure concentrations of chemicals.

OBJECTIVE: This study determined the applicability of Japanese working environment measurements to assessment of personal exposure concentrations of chemicals by comparing both levels of concentrations. METHODS: The chemicals measured in this study comprised eight kinds of vaporous chemicals as well as two kinds of chemicals in dust. Personal exposure measurements, Japanese working environment measurements and spot sampling measurements were undertaken in 70 companies. RESULTS: Personal exposure concentrations and the arithmetic mean value (EA2) of the working environment measurement concentrations obtained according to the Japanese working environment control system had statistically positive correlations (r=0.732-0.893, p<0.01) after logarithmic transformation. The 5th to 95th percentile values of personal exposure concentrations divided by EA2 ranged from 0.17 to 7.69 for vaporous chemicals and from 0.27 to 18.06 for dust. There was a relatively large difference between the personal exposure concentrations and the EA2 obtained in weighing, forming and bonding use-processes. In such cases, the B-value measured in ten minutes in the Japanese working environment control system, which is almost the same as the spot measurement concentration in this study, is supposed to be substituted for the EA2 value. CONCLUSIONS: Ten times the EA2 of the working environment measurement concentrations, or ten times the B-value, obtained according to the Japanese working environment control system can be used to conservatively estimate the personal exposure concentrations in EU workplaces as well as in occupational exposure scenarios of the Regulation on Registration, Evaluation, Authorisation and Restriction of Chemicals.

Urinary 1-hydroxypyrene as a comprehensive carcinogenic biomarker of exposure to polycyclic aromatic hydrocarbons: a cross-sectional study of coke oven workers in China.

PURPOSE: Polycyclic aromatic hydrocarbons (PAHs) are multiple compounds that include many carcinogens. We conducted a cross-sectional study in steel plant workers in Anshan, China, to identify biomarkers that reflect the carcinogenicity of PAHs. METHODS: Subjects were 57 workers and 20 controls. Level of personal exposure to PAHs was measured using GC-MS. In accordance with the assessment methods defined by the United States Environmental Protection Agency (US EPA), 15 PAHs were selected for the analysis. For the measurement of urinary metabolites, urine samples were treated with ß-glucuronidase and analyzed using HPLC with a fluorescence detector. RESULTS: The mean range of personal exposure to 15 PAHs (total PAHs) was 178.85, 47.08-1,329.45 (geometric mean, 5th and 95th percentile) µg/m(3). Ten known urinary metabolites (1-hydroxynaphthalene, 2-hydroxynaphthalene, 2-hydroxyfluorene, 1-hydroxyphenanthrene, 3-hydroxyphenanthrene, 9-hydroxyphenanthrene, 1-hydroxypyrene, 3-hydroxybenz[a]anthracene, 6-hydroxychrysene, and 3-hydroxybenzo[a]pyrene) and four unknown peaks were detected. The highest correlation was between total PAHs and urinary 2-hydroxynaphthalene (Spearman r = 0.716, P < 0.01). Among the detected urinary metabolites, 2-hydroxyfluorene, 1-hydroxyphenanthrene, 3-hydroxyphenanthrene, and 1-hydroxypyrene were found to correlate significantly with the "Σ carcinogenic potency of PAHs" (sum of seven carcinogenic PAHs calculated from the levels of personal PAHs and relative potency factors), and with the greatest correlation found for 1-hydroxypyrene (Spearman r = 0.630, P < 0.01). CONCLUSIONS: The analysis of personal exposure to 15 PAHs and 10 urinary metabolites, and calculation of Σ carcinogenic potency, indicated that urinary 1-hydroxypyrene was the most comprehensive carcinogenic biomarker of exposure to PAHs.

Simultaneous measurement of urinary total nicotine and cotinine as biomarkers of active and passive smoking among Japanese individuals.

OBJECTIVES: Measuring urinary cotinine is a popular and established method of biologically monitoring exposure to tobacco smoke. However, the lower detection limit of cotinine often impedes the evaluation of passive (second-hand) smoking and this, together with unconverted nicotine, does not reflect actual levels of exposure. Furthermore, a portion of the Japanese population might have decreased ability to metabolize nicotine. The present study was therefore carried out to validate the simultaneous analysis of total concentrations of free nicotine and cotinine and their glucuronides to determine actual levels of voluntary and involuntary exposure to cigarette smoke. METHODS: Urine samples from 118 Japanese smokers and 117 non-smokers were analyzed using gas chromatography-mass spectrometry. Voluntary and involuntary smoking status was self-reported and workplace smoking restrictions were objectively evaluated. RESULTS: The integrated sum of all concentrations showed 2.2- and 2.4-fold higher total levels (free and glucuronide) of nicotine and cotinine relative to the free levels. Median (quartiles) of total nicotine and cotinine were 1635 (2222) and 3948 (3512) ng/mL in smokers, and 3.5 (5.3) and 2.8 (4.2) ng/mL in non-smokers. Concentrations of urinary nicotine were higher than those of cotinine in 21 % of smokers and in 54 % of non-smokers. Nicotine and cotinine levels were significantly associated with a smoking habit, as well as being significantly associated with the workplace and home environments of non-smokers. CONCLUSIONS: The present method can monitor voluntary and involuntary exposure to tobacco smoke. Measuring total urinary nicotine levels might be useful for analyzing exposure to cigarette smoke among non-smokers.