Lack of information on gender differences in the package inserts of prescription drugs in Japan.

The package inserts of prescription drugs provide essential information for the proper administration of pharmacotherapy. The incidence of adverse reactions for several drugs is known to be higher in women than in men. However, no studies have examined whether information on gender differences is included in Japanese package inserts. Therefore, this study investigated information on gender differences in the package inserts of Japanese prescription drugs, using the drug information database JAMES provided by the Medical Information System Development Center and the Japan Pharmaceutical Information Center. Non-proprietary names of prescription drugs were yielded 1,679 in Japan. Of the 1,679 ingredients in package inserts of prescription drugs, 76 (4.5%) included information on gender differences. The number of inserts that contained information on gender differences in the "DOSAGE AND ADMINISTRATION," "ADVERSE REACTIONS," and "PHARMACOKINETICS" sections was 3, 16, and 62, respectively. Furthermore, in the "ADVERSE REACTIONS" section, 15 of the 16 inserts mentioned a higher frequency of adverse reactions in women compared with men. Importantly, most of the inserts with information on gender differences in the "PHARMACOKINETICS" section mentioned a higher area under the curve for women than for men. Most of the package inserts of prescription drugs with information on gender differences provide useful information aimed at preventing risks in women. However, there is an extreme lack of information on gender differences in the package inserts of prescription drugs in Japan, and we consider enhancing information on gender difference as an urgent issue.

[Survey of occupational health-related activities conducted at hospitals in the Kanto region (2020)].

OBJECTIVE: To survey occupational health-related activities conducted at hospitals certified by the Japan Council for Quality Health Care in the Kanto region of Japan. METHODS: The survey tool was sent to 470 hospitals and comprised the following items: hospital size, occupational health system, infection control practices, mental health services, promotion of work system reforms, and priorities in achieving occupational health. RESULTS: A total of 140 hospitals completed the survey. A monthly workplace inspection was conducted in approximately 60% of the hospitals. Testing of new employees for hepatitis and four other viruses was conducted in approximately 65% of the hospitals, and influenza vaccination was administered to the employees in all the hospitals. Most hospitals provided mental health services to their workers, which included consultation with an occupational physician. Work system reforms for changing conference time and task shifting or sharing were adopted in approximately 50% of the hospitals. Prevention of blood-borne pathogens, respiratory infections, and healthcare coverage for healthcare workers was identified as areas of improvement in several hospitals. CONCLUSIONS: Legally required infection control and occupational health-related practices were conducted in most hospitals. Additionally, several hospitals undertook work system reforms, including the management of changes in conference time and task shifting or sharing.

Prolonged carriage of ESBL-producing enterobacterales and potential cross-transmission among residents in geriatric long-term care facilities.

Previous studies indicated residents in geriatric long-term care facilities (LTCFs) had much higher prevalence of extended-spectrum ß-lactamase-producing Enterobacteriaceae (ESBL-E) carriage than the general population. Most ESBL-E carriers are asymptomatic. The study tested the hypothesis that residents with ESBL-E carriage may accumulate inside geriatric LTCFs through potential cross-transmission after exposure to residents with prolonged ESBL-E carriage. 260 residents from four Japanese LTCFs underwent ESBL-E testing of fecal specimens and were divided into two cohorts: Cohort 1,75 patients with ≥ 2 months residence at study onset; Cohort 2, 185 patients with < 2 months residence at study onset or new admission during the study period. Three analyses were performed: (1) ESBL-E carriage statuses in Cohort 1 and Cohort 2; (2) changes in ESBL-E carriage statuses 3-12 months after the first testing and ≥ 12 months after the second testing; and (3) lengths of positive ESBL-E carriage statuses. Compared with the residents in Cohort 1, a significantly larger proportion of residents in Cohort 2 were positive for ESBL-E carriage (28.0% in Cohort 1 vs 40.0% in Cohort 2). In the subsequent testing results, 18.3% of residents who were negative in the first testing showed positive conversion to ESBL-E carriage in the second testing, while no patients who were negative in the second testing showed positive conversion in the third testing. The maximum length of ESBL-E carriage was 17 months. The findings indicated that some residents acquired ESBL-E through potential cross-transmission inside the LTCFs after short-term residence. However, no residents showed positive conversion after long-term residence, which indicates that residents with ESBL-E carriage may not accumulate inside LTCFs. Practical infection control and prevention measures could improve the ESBL-E prevalence in geriatric LTCFs.

[Effective education on infection control for workers dispatched overseas].

OBJECTIVES: The number of workers dispatched to developing countries has increased recently. The sanitary conditions in these countries are different from those in developed countries and from what the workers are used to. Therefore, health control, especially infection control, is an important consideration for working there. In this study, we investigate workers' needs as well as the occupational physicians' skills concerning working in developing countries. We propose a more effective education system for health control. METHODS: Regarding workers who have lived in developing countries, we surveyed the company profiles, duration of stay, vaccination status, infectious education, medical assistance, and satisfaction with infection control strategies of their employer companies. Regarding occupational physicians, we surveyed their profiles, their experiences in consultation, and advice from/to the workers dispatched to developing countries as well as their suggestive advice for staying there. RESULTS: Factors that contributed to workers' satisfaction with their employment companies were prior education and health consulting services in addition to company size. Many occupational physicians believed that this kind of information should be supplied but they did not have the confidence to provide it. CONCLUSIONS: Workers who are dispatched overseas should receive prior education and access to health consulting services. It is necessary for information providers such as occupational physicians to be knowledgeable in travel medicine.

Improvement of hand hygiene adherence among staff in long-term care facilities for elderly in Japan.

INTRODUCTION: Hand hygiene is crucial for infection control in long-term care facilities for elderly (LTCFEs), because it can be easily implemented in the low-resource settings of LTCFEs. This study investigated the actual status of hand hygiene adherence in LTCFEs, identified the factors inhibiting its appropriate implementation, and evaluated the effectiveness of a hand hygiene promotion program. METHODS: In this before-and-after study, participants were staff members (n = 142) at two LTCFEs in Gunma Prefecture, Japan. We modified the World Health Organization's "five moments for hand hygiene" and assessed participants' hand hygiene adherence rates in four situations: (1) Before touching around a resident's mucous membrane area; (2) Before medical practice or clean/aseptic procedures; (3) After body fluid exposure/risk or after touching around a resident's mucous membrane area; and (4) After touching a resident's contaminated environments. The study was divided into four phases. In Phase 1, participants self-assessed their hand hygiene adherence using a questionnaire. In Phase 2, we objectively assessed participants' pre-intervention adherence rates. In Phase 3, an intervention comprising various hand hygiene promotion measures, such as education and hands-on training on hand hygiene practices and timings, was implemented. In Phase 4, participants' post-intervention adherence rates were objectively measured. RESULTS: Although most participants reported high hand hygiene adherence rate in the self-assessment (93.1%), the pre-intervention evaluation revealed otherwise (16.8%). Participants' post-intervention adherence rates increased for all four situations (77.3%). CONCLUSION: The intervention program helped increase participants' hand hygiene adherence rates, indicating its effectiveness. Similar interventions in other LTCFEs may also improve adherence rates.

Influenza Outbreak and a Group Meal in a Geriatric Long-term Care Facility in Japan.

Influenza outbreaks at geriatric long-term care facilities (g-LTCFs) can be deadly and their prevention is important. However, the factors influencing disease transmission in g-LTCFs remain controversial. In this descriptive study, we tried to identify the potential risk factors influencing influenza outbreaks that occurred in different influenza seasons within a single g-LTCF with 100 residents in Gunma Prefecture. We reviewed the detailed facility records for all influenza cases in both residents and staff between January 2012 and June 2020. Facility preventive measures were also reviewed. We found that community meals may have been a potential source of transmission leading to the outbreaks. When influenza infection is noted, implementation of strict preventive measures and restriction of meal provision to resident rooms may help to prevent disease transmission and the development of an outbreak. Such measures may also be useful to prevent the transmission of other serious droplet-borne diseases within g-LTCFs.

Distribution of Extended-Spectrum ß-Lactamase Genes and Antimicrobial Susceptibility among Residents in Geriatric Long-Term Care Facilities in Japan.

A high prevalence of extended-spectrum ß-lactamase-producing Enterobacterales (ESBL-PE) may call for monitoring in geriatric long-term care facilities (g-LTCFs). We surveyed the distribution of ESBL-causative gene types and antimicrobial susceptibility in ESBL-PE strains from residents in g-LTCFs, and investigated the association between ESBL-causative gene types and antimicrobial susceptibility. First, we analyzed the types of ESBL-causative genes obtained from 141 ESBL-PE strains collected from the feces of residents in four Japanese g-LTCFs. Next, we determined the minimum inhibitory concentration values for alternative antimicrobial agents against ESBL-PE, including ß-lactams and non-ß-lactams. Escherichia coli accounted for 96% of the total ESBL-PE strains. Most strains (94%) contained blaCTX-M group genes. The genes most commonly underlying resistance were of the blaCTX-M-9 and blaCTX-M-1 groups. Little difference was found in the distribution of ESBL-causative genes among the facilities; however, antimicrobial susceptibility differed widely among the facilities. No specific difference was found between antimicrobial susceptibility and the number of ESBL-causative genes. Our data showed that ESBL-PEs were susceptible to some antimicrobial agents, but the susceptibility largely differed among facilities. These findings suggest that each g-LTCF may require specific treatment strategies based on their own antibiogram. Investigations into drug resistance should be performed in g-LTCFs as well as acute medical facilities.

Efficacy and Effectiveness of Showerheads Attached with Point-of-use (POU) Filter Capsules in Preventing Waterborne Diseases in a Japanese Hospital.

Tap water contamination is a growing concern in healthcare facilities, and despite chlorination, tap water in these facilities contains several pathogenic microorganisms causing healthcare-associated waterborne infections or nosocomial outbreaks. Shower units are particularly prone to contamination as they are conducive for bacterial growth and can even produce bioaerosols containing pathogenic bacteria. Shower units coupled with point-of-use (POU) water filters are a simple and safe option; however, their efficacy has been under-reported. Therefore, we determined the efficacy of showerheads attached with a POU filter capsule in preventing infections in our hospital. We investigated the presence of pathogenic bacteria in water sampled from three shower units. After replacing the original shower units with new ones incorporated with a sterile-grade water filter capsule (0.2 µm; QPoint™), the water samples were analyzed for up to 2 months. The POU filters removed several pathogenic bacteria (Mycobacterium, Pseudomonas, Stenotrophomonas, Aeromonas, and Klebsiella spp.). Filter effectiveness depends on regional water quality and we believe that effective tap water treatment combined with the use of POU filters (introduced at a reasonable cost in healthcare facilities) can considerably minimize waterborne diseases in hospitals and improve patient care.

Association between length of residence and prevalence of MRSA colonization among residents in geriatric long-term care facilities.

BACKGROUND: A high prevalence of methicillin-resistant Staphylococcus aureus (MRSA) colonization has been reported among residents in geriatric long-term care facilities (LTCFs). Some studies indicate that MRSA might be imported from hospitals into LTCFs via resident transfer; however, other studies report that high MRSA prevalence might be caused by cross-transmission inside LTCFs. We aimed to assess which factors have a large impact on the high MRSA prevalence among residents of geriatric LTCFs. METHODS: We conducted a cohort study among 260 residents of four geriatric LTCFs in Japan. Dividing participants into two cohorts, we separately analyzed (1) the association between prevalence of MRSA carriage and length of LTCF residence (Cohort 1: n = 204), and (2) proportion of residents identified as MRSA negative who were initially tested at admission but subsequently identified as positive in secondary testing performed at ≥2 months after their initial test (Cohort 2: n = 79). RESULTS: Among 204 residents in Cohort 1, 20 (9.8%) were identified as positive for MRSA. Compared with residents identified as MRSA negative, a larger proportion of MRSA-positive residents had shorter periods of residence from the initial admission (median length of residence: 5.5 vs. 2.8 months), although this difference was not statistically significant (p = 0.084). Among 79 residents in Cohort 2, 60 (75.9%) were identified as MRSA negative at the initial testing. Of these 60 residents, only one (1.7%) had subsequent positive conversion in secondary MRSA testing. In contrast, among 19 residents identified as MRSA positive in the initial testing, 10 (52.6%) were negative in secondary testing. CONCLUSIONS: The prevalence of MRSA was lower among residents with longer periods of LTCF residence than among those with shorter periods. Furthermore, few residents were found to become MRSA carrier after their initial admission. These findings highlight that MRSA in LTCFs might be associated with resident transfer rather than spread via cross-transmission inside LTCFs.

Correction to: Comparison of hepatitis B vaccine efficacy in Japanese students: a retrospective study.

Following publication of the original article [1], the authors spotted errors in their paper concerning the positive rate in the right side in Table 2.

[Analysis of occupational health activities through classifying reports from medical facilities in Japan].

OBJECTIVES: The objectives of this study were to analyze current trends in occupational health activities by classifying reports from medical facilities in Japan. METHODS: Reports of current workplace-level occupational health activities from medical activities that were collected by the Japan Medical Association Occupational Health Committee were used for the study. Of 5,000 questionnaire forms sent to medical facilities, 1,920 responses were returned. The freely described reports on ongoing occupational health activities contained in these responses were classified according to each of the following aspects of reported activities: 1) details of occupational health activities including main actors in workplace-level actions; and 2) approaches taken for occupational safety and health. The classification of the reports was implemented by a working group comprising selected occupational health practitioners and researchers. RESULTS: Among 1,920 survey responses, 581 valid texts were analyzed. Altogether, 1,044 occupational health activities currently undertaken by the facilities were extracted. The reported activities that were classified according to details of occupational health activities mainly comprised "Measures for preventing overwork, labor management, and work-style reform" (35.7%), "Measures for improving mental health" (21.0%), and "Review of occupational safety and health management systems" (19.3%). Medical facilities implementing "Measures for mental health" alongside "Measures for preventing overwork, labor management, and work-style reform" were reported in 13.2% of the responding medical facilities. "Occupational health professionals or safety and health management staff" (71.7%) were the most frequent main actors of these activities, followed by "Members of the workplace" (18.4%) and "Outsourced experts" (2.4%). "Comprehensive safety and health management" (42.0%) was the most common approach taken for occupational safety and health, followed by "Management focusing on topics" (23.8%) and "Case management" (16.5%). Most of these activities focused on primary prevention aimed at labor management including prevention of overwork, work-style reform, and mental health promotion. Another key trend could be "Teamwork among occupational safety and health staff, workers, and employers at respective workplaces as well as outsourced experts." DISCUSSION: Several key trends were extracted from current occupational health activities at medical facilities. In most cases, these measures were implemented simultaneously. This suggests the importance of combining primary prevention measures for mental health with measures for labor management including prevention of overwork. These activities reflect emerging trends that incorporate teamwork between experts, workers, and employers, and provide new perspectives on workplace-level occupational safety and health activities.

Comparison of hepatitis B vaccine efficacy in Japanese students: a retrospective study.

BACKGROUND: Two types of recombinant hepatitis B virus (HBV) vaccines are available in Japan. One type uses the antigen from genotype A (Heptavax-II®) and the other uses the antigen from genotype C (Bimmugen®). Potential differences in productivity of the hepatitis B virus surface (HBs) antibody between vaccines have not been studied in detail. We investigated the acquired level of immunity against HBV in association with two vaccines, their administration routes, and patient sex. We present the appropriate inoculation method based on the characteristics of each vaccine. METHODS: Data of 1135 medical and nursing students (481 men and 651 women) were used, each of whom was unvaccinated prior to recruitment and subsequently vaccinated three times prior to the study. The vaccine type and administration route differed according to the university department and enrolling year. The students were categorized into the following three groups: Bimmugen®-subcutaneous group, Heptavax-II®-subcutaneous group, and Heptavax-II®-intramuscular group. The total and sex-segregated positive rates of the HBs antibody among the three groups were compared using Pearson's chi-square test. The effect of time between the HBs antibody test and vaccine administration on the HBs antibody level was also analyzed similarly. RESULTS: The Bimmugen®-subcutaneous group showed the highest positive HBs antibody rate (92.0%) among the three groups. In the Heptavax-II® group, the positive rate was 66.3% in the subcutaneous injection group and 89.1% in the intramuscular injection group. There was a significant difference among these three groups. In terms of sex, women showed a significantly higher average positive rate than men in each group. In terms of effect of time between the HBs antibody test and vaccine administration, no significant differences were observed. CONCLUSIONS: Bimmugen® is associated with more effective HBs antibody production than Heptavax-II® in Japanese students. However, the Heptavax-II® vaccine is an appropriate choice for HBV vaccination in areas where HB is caused predominantly by HBV genotype C. With both vaccines, women tended to acquire more immunogenicity than men. Intramuscular injection may be the preferred administration route due to the possibility of local reactions.

A strategy for the reduction of formaldehyde concentration in a hospital pathology laboratory.

OBJECTIVES: Formaldehyde is routinely used in pathology laboratories. The threshold limit value of formaldehyde determined by American and Japanese organizations is 0.1 ppm, which is similar to the indoor air quality guideline value (0.08 ppm). Therefore, maintaining low formaldehyde concentrations in the workplace is imperative. The purpose of this study was to reduce the concentration of formaldehyde in a hospital pathology laboratory, in which approximately 15 000 pathological diagnoses are conducted yearly, using hardware and software interventions. METHODS: Although this laboratory had various ventilation systems, the formaldehyde concentration was high. Based on the Japanese work environment measurement system, the workplace was categorized as control class III, suggesting that improvements to workplace conditions were required. First, engineering controls were implemented and workers were asked not to block the ventilation system and not to keep waste fluid tanks open. However, the workplace required further improvement. Next, using a video camera and a formaldehyde detector, we attempted to visually educate workers about how much formaldehyde is emitted from the sample container based on the type of action undertaken. RESULTS: After the first intervention, the workplace improved to control class II. Control class II indicates that the workplace condition is between classes I and III; a good workplace condition is classified as class I. Although the work environment was still categorized as control class II after the second intervention, this intervention led to the further improvements. CONCLUSIONS: The hardware and software interventions and safe working habits were effective in improving the work environment.

An 18-Year Follow-up Survey of Dioxin Levels in Human Milk in Japan.

BACKGROUND: Globally, few published studies have tracked the temporal trend of dioxin levels in the human body since 2000. This study describes the annual trend of dioxin levels in human breast milk in Japanese mothers from 1998 through 2015. METHODS: An observational study was conducted from 1998 through 2015. Participants were 1,194 healthy mothers following their first delivery who were recruited annually in Japan. Breast milk samples obtained from participants were analyzed using gas chromatography and mass spectrometry for dioxins, including polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (PCBs). RESULTS: Mean age was 29.5 years, and 53% of participants were 20-25 years old. A declining trend in total dioxin levels was found, from a peak of 20.8 pg toxic equivalence (TEQ)/g fat in 1998 to 7.2 pg TEQ/g fat in 2014. Data from the last 5 years of the study indicated a plateau at minimal levels. In contrast, an increasing trend was found in the mean age of participants during the last 5 years. Although significantly higher dioxin levels were observed in samples from older participants, an upward trend in dioxin levels was not observed, indicating that dietary and environmental exposure to dioxins had greatly diminished in recent years. CONCLUSIONS: Dioxin levels in human breast milk may be approaching a minimum in recent years in Japan. The findings may contribute to global reference levels for environmental pollution of dioxins, which remains a problem for many developing countries.

Primary Hepatic Angiosarcoma: A Case Report with 10-Year Patient Medical Data.

In the current study, we report a case of a 46-year-old man who presented with sudden abdominal pain and was diagnosed with rupture of hepatic angiosarcoma (HAS). He underwent surgery, but died 13 days after the onset of the abdominal pain. Chronic exposure to carcinogens, such as thorium dioxide, arsenic, vinyl chloride, and radium, is associated with HAS. However, our patient had not been exposed to such carcinogens. He had submitted himself for annual medical checkups since he was employed. His liver was cirrhotic, and medical history data showed that he had had fatty liver for at least 10 years before HAS onset. Although liver cirrhosis may play a role in the occurrence of HAS, the connection of chronic fatty liver in the tumorigenesis remains unclear. Case reports regarding HAS with fatty liver are few. To the best of our knowledge, this is the first case of HAS occurring in a cirrhotic liver that advanced from persistent fatty stage. Given that HAS is a rare tumor, data collection is important for investigating its pathophysiology. Case presentations considering health conditions before HAS onset are limited; therefore, we present a case of HAS with annual health checkup data before disease onset.

Heavy metal exposure, in combination with physical activity and aging, is related with oxidative stress in Japanese women from a rural agricultural community.

This study aimed to evaluate the relationships between oxidative stress and heavy metal exposure (lead [Pb] and cadmium [Cd]), as well as co-factors such as physical activity and age, in Japanese women. This study was conducted with female subjects from a rural agricultural community in Japan. Subjects were asked to complete lifestyle-related questionnaires and undergo a group health examination. Physical activity, alcohol consumption, body mass index, and other demographic information were collected. Blood and urine samples were collected to measure urinary 8-hydroxydeoxyguanosine (8-OHdG) levels and blood and urinary Cd and Pb concentrations. Urine samples were analyzed using high performance liquid chromatography and flameless atomic absorption spectrometry; blood samples were analyzed using inductively coupled plasma-mass spectrometry. Age, physical activity, and blood and urinary Cd and Pb concentrations were included in structural equation modeling analysis. Two latent factors for heavy metal exposure and physical activity were produced to predict the total influence of the variables. The final model was good: CMIN/DF = 0.775, CFI = 1.000, GFI = 0.975, AGFI = 0.954, RMSEA = 0.000. 8-OHdG levels were positively associated with heavy metal exposure, physical activity, and age (standard ß of path analysis: 0.33, 0.38, and 0.20, respectively). Therefore, oxidative stress is associated with both, environmental and lifestyle factors, in combination with aging.

Exposure assessment of lead from food and airborne dusts and biomonitoring in pregnant mothers, their fetus and siblings in Karachi, Pakistan and Shimotsuke, Japan.

AIM: Exposure assessment of lead (Pb) and Arsenic (As) from food, water, and house dust intake were assessed among pregnant women, their children and fetuses in Pakistan and Japan, as well as their body burden of the metals in their blood. METHOD: Fifty families which included a pregnant woman, a fetus and the 1-3-year-old siblings were recruited in Karachi and Khairpur in Pakistan, and Shimotsuke and Asahikawa in Japan, respectively. Their dietary exposure to Pb and As was measured in 3-day food duplicates and drinking water by ICP-MP. Pb in house dust and respirable dust was evaluated with an energy dispersive X-ray fluorescence spectrometry. Non-radioactive isotope Pb profiles of blood specimens will be compared with those of the exposure origins, such as food duplicates, respirable house dust, the soils nearby, and gasoline. RESULTS: Judging from the data collected and analyzed so far, contribution from dietary intake is highly correlated to higher body burden of Pb among Pakistani mothers. Additional data analyses will reveal the status of Pb and As body burden in Pakistani mothers, fetuses and their siblings, and causal sources of high body burden is delineated by Pb isotope profile analysis of different sources of Pb exposure.

A study of the association between urinary aluminum concentration and pre-clinical findings among aluminum-handling and non-handling workers.

BACKGROUND: Aluminum is considered to be a relatively safe metal for humans. However, there are some reports that aluminum can be toxic to humans and animals. In order to estimate the toxicity of aluminum with respect to humans, we measured the aluminum concentration in urine of aluminum-handling and non-handling workers and investigated the relationships between their urinary aluminum concentrations and pre-clinical findings. METHODS: Twenty-three healthy aluminum-handling workers and 10 healthy non-aluminum-handling workers participated in this study. Their medical examinations, which were otherwise unremarkable, included the collection of urine and blood. Urinary aluminum levels were analyzed using ICP analysis. As pre-clinical tests, we measured KL-6, SP-D, TRCP-5b, IL-6, and IL-8 in blood and δ-ALA and ß2-microglobulin in urine. These were considered to be lung, bone, kidney and inflammation markers. Moreover, we measured 8-OHdG in urine as an oxidative DNA damage marker. RESULTS: The aluminum concentration in urine ranged from 6.9 to 55.1 µg/g cre (median: 20.1 µg/g cre) in the aluminum-handling workers and from 5.6 to 15.6 µg/g cre (median: 8.8 µg/g cre) in the non-aluminum-handling workers, with a significant difference between them. In the pre-clinical findings, there were no significant differences between these two groups except in the case of δ-ALA. However, there were no significant relationships between aluminum concentration and the pre-clinical findings, work years, age or 8-OHdG in the aluminum-handling workers. CONCLUSIONS: While the excretion of aluminum in urine was elevated in aluminum-handling workers, our findings suggest that low-dose aluminum is not directly harmful to humans, at least when workers' urinary aluminum concentration is below 55 µg/g cre.

Biomonitoring of mercury, cadmium, and lead exposure in Japanese children: a cross-sectional study.

OBJECTIVES: To measure current Hg, Cd, and Pb exposure in Japanese children, and to estimate dietary intakes of foods responsible for high body burden. METHODS: Blood, hair, and urine samples were collected from 9 to 10-year-old 229 children in Asahikawa and measured for Hg, Cd, and Pb in these matrices. Diet history questionnaire was used to estimate intake of marine foods and other food items. Hg level was measured by cold vapor atomic absorption spectrometry. Cd and Pb levels were determined with inductively coupled plasma mass spectrometry. RESULTS: Geometric mean (GM) of blood Hg, Cd, and Pb was 4.55 µg/L, 0.34 µg/L, and 0.96 µg/dL, respectively. Urinary Cd level was 0.34 µg/g creatinine (GM) and hair Hg was 1.31 µg/g (GM). Approximately one-third (35%) of blood samples had Hg level above the U.S. EPA reference dose (RfD; 5.8 µg/L). Hair Hg level exceeded U.S. EPA RfD (1.2 µg/g) in 59 % samples. Children in the upper quartile of blood Hg level had significantly higher intake of large predatory fish species compared to those in the lower quartile of blood Hg. CONCLUSIONS: Those with high blood Hg level may be explained by more frequent intake of big predatory fish. Cd and Pb exposure is generally low among Japanese children. As no safety margin exists for Pb exposure and high exposure to MeHg is noted in Japanese population; periodic biomonitoring and potential health risk assessment should continue in high-risk populations, notably among children.

A pilot study on the stability of toluene in blood from workers.

BACKGROUND: Biological monitoring is used to assess toluene exposure in medical examinations. The American Conference of Industrial Hygienists, Japanese Society for Occupational Health and Deutsche Forschungsgemeinschaft have proposed various biological exposure determinants, such as toluene in blood and urine, and o-cresol in urine. Toluene in blood is a common biomarker among them. Toluene is a volatile organic solvent; therefore, sample preservation under appropriate conditions before measurement is necessary. However, little study has been done on the stability of toluene in workers' blood samples under conditions simulating those of a medical examination. FINDING: We carried out a pilot study on the stability of toluene in blood from humans, according to different methods of sample preservation. Toluene in blood was analyzed by head space-gas chromatography/mass spectrometry. The sealing performance of the vial was examined by using toluene-added blood and the stability of toluene in blood according to the preservation period was examined by using blood from toluene-handling workers, which was collected with vacuum blood tubes. The sealing performance of the headspace vial used in this study was good for three days and toluene in blood in tubes from workers was stable at least within 8 hours up to blood packing at 4°C. CONCLUSION: We could propose that the collected blood need only be transferred into headspace vials on the collection day and analyzed within a few days, if the samples are preserved at 4°C. Our data size is limited; however, it may be considered basic information for biological monitoring in medical examinations.