A new sampling method of nicotine in ETS was developed by using a semi-active sampler, which enables simultaneous collection of nicotine in the gas phase and that adsorbed on the fine particles in the ETS. The semi-active sampler is a tube-type sampler made of aluminum in which a polyurethane form (PUF) was placed as an adsorption medium for nicotine. Air sample is introduced to the sampler by the flow induced by a small fun installed at the outlet of the sampler. Nicotine of both gas phase and adsorbed on particulates in the sampled air would be captured onto the adsorbent, PUF. The PUF used as an adsorbent was pretreated with L-ascorbic acid, which improved the holding performance of the collected nicotine onto the PUF. The average concentration of nicotine in a smoking room sampled and determined by the active sampling method using XAD-4 showed a good linear relationship (R² = 0.99) with the amount of nicotine collected by the semi-active sampling method. The sampling rate of the semi-active sampler was determined 578 mL/min, which is 60 times greater than that of a conventional passive sampler (modified MoNIC). The present method was applied to some field studies on the measurement of personal exposure to nicotine in the ETS, with which the inhaled cigarette equivalent (CE) by a passive smoker can be estimated.

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With the improvement of airtightness of Japan house, it has become easy for fungi to proliferate in the high humidity environment such as bathroom. The primary purpose of this study is to clarify the density and composition of dirt on various parts of prefabricated bathroom and to elucidate relationship between the dirt density and fungal density. In addition, the assimilating test with actual dirt was conducted by Cladosporium sp., a typical fungi species in bathroom.
Our results showed that dirt density was in the range of 57-790 μg/cm². Ceiling had the lowest and outlet port wall region had the highest dirt density among the different parts in each tested bathroom. The mean compositions of keratin protein, triglycerides and sodium fatty acids in dirt were 50, 24, and 15%, respectively and those three components consisted about 90% of the total dirt. Fungal density was significantly positively correlated with keratin protein and triglyceride density.
The assimilating test showed that human dirt in a bathroom can be a source of nutrients for Cladosporium sp.. A component of sebum, triglyceride, in addition to keratin protein promoted the mycelial growth of Cladosporium sp..
From the observation in this study, we showed that the kinetics of outbreak, adhesion, discharge and persistence of dirt were different depending on the part of a bathroom. In addition, we also showed that keratin protein and a sebum component (triglyceride) were important to the proliferation of Cladosporium sp.. This is the first report that showed Cladosporium sp. can proliferate with dirt density that occurs in actual bathroom environment.

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There exist some people who claim his/her body odor provokes allergy-like reactions of people in their near vicinity, which include sneezing, runny nose, cough, itchy eyes, and red eyes. Such a diathesis, called "people allergic to me (PATM)", has been gradually recognized in other countries. However, the term "PATM" has been hardly heard in Japan, and there have been no reports focusing on PATM in academic journals so far. After receiving a request for advice from a male subject, we conducted a medical interview, measurement of trace gases released from human skin surface, measurement of volatile chemicals from the subject's underwear, and microbiological test of the nasal cavity of the patient. The results showed that greater amounts of chemicals, such as toluene and xylene, were detected in skin-gas samples from the subject than in those from a control subject. Moreover, some chemicals, such as hexane, propionaldehyde, and toluene, which showed relatively high levels of emission from the subject's skin, were also detected in the underwear of the subject. The microbial species that was isolated from the nasal cavity of the subject with the highest abundance was Staphylococcus epidermidis (Bacilli; Bacillales), which is known as a resident skin flora. In addition, Arthrobacter phenanthrenivorans (Actinobacteria; Micrococcales), which releases a ditch-like smell, was cultured on isolation medium, and its presence might have a relationship with the PATM condition. Furthermore, Rhodotorula mucilaginosa (Basidiomycota; Sporidiales), which is a fungus that is known to cause red water scale in bathrooms/washrooms, was isolated from the nasal cavity of the subject. To the best of our knowledge, the isolation of this latter species from the human nasal cavity has not previously been reported. Taken together, there is a possibility that PATM is not a product of patients' imagination but represents a genuine disease that has yet-to-be-investigated.

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Oxidative stress induced by fine particulate matter 2.5 (PM_2.5) is a potential cause of adverse health effects due to production of reactive oxygen species (ROS). Currently, dithiothreitol (DTT) assay is mostly used in epidemiological studies for the measurement of oxidative potential (OP) of PM_2.5. However, the number of applications is somewhat limited because the assay requires tedious procedures with care due to use of photodegradable reagents. Then, we have developed a simple and rapid methodology for the measurement the OP of PM_2.5 by applying Flow Injection Analysis (FIA) to the DTT assay. This paper describes theoretical backgrounds of the FIA-DTT assay including concept of oxidative stress, and principle of DTT assay, and briefly demonstrates results of field measurement of OP of PM_2.5 collected in outdoor and indoor air.

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Passive sampling method for measuring total volatile organic compounds (TVOC) in indoor air was explained in this article. TVOC means the amount of volatile organic compounds (VOC) in indoor air. TVOC measurements have been beneficial in determination of indoor air pollution by VOC. In many studies, TVOC measurements have been done as Sum of VOCs which is the total value of individual VOC. But, TVOC measurements occasionally have been done as total area with response factor of toluene. Passive sampling for TVOC is suitable for indoor air quality survey, because it is convenient. Since TVOC is composed of different VOC of various physical-chemical properties, adsorbents that have high adsorption / desorption efficiency are recommended to use for the passive sampler. And samplers that have high SR are recommended to select. TVOC measurements by passive sampler are expected to have high performance as screening method. Furthermore, it will be necessary to consider recalculation of TVOC concentration carried out by applying unique sampling rate values of some VOC and estimated value of sampling rate to the retention time of total ion chromatogram for accurate quantification.

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Thirdhand smoke (THS) is the residual tobacco smoke after extinguishing a cigarette. Some constituents of the tobacco smoke may stay in the air after extinguish, but most of them will be adsorbed onto the surfaces such as wallpapers, clothes. The adsorbed components will be gradually re-emitted into the atmosphere for a long period of time, and could be taken up by a human body. In our daily life, THS can be noticed through malodor or color changes of the wallpaper of a smoking room. However, THS has been recognized as a new type of passive smoking issue since Winckoff et al. published a paper on THS in 2009. In 2010, Sleiman et al. reported the de novo formation of tobacco-specific nitrosamines (TSNAs), known as carcinogens, and their findings have boomed the research on THS. In this article we aimed to overview the current state of the THS research activities from the viewpoints of the characteristics, chemistry, field surveys, toxicity, health effects, and exposure assessments of THS. THS is characterized by the four "R"s, namely, Remain, Reaction, Re-emit, and Re-suspended. THS remains in the environment for a long period, and be aged, and the chemical composition of THS is different from that of ETS, and THS contains some compounds specific to THS, due to the chemical reactions during the aging. Field surveys of THS have been conducted by the direct air measurements, wiping the surfaces, analysis of dust-adsorbed compounds. The higher concentrations of nicotine and detection of TSNAs have been reported for the smoking environments. Exposures to the THS extract induced various kinds of DNA damages. The metabolic or immunity systems were affected by the THS extract exposure to test animals. Exposure assessments suggest the THS exposures to infants will be more serious than to adults. More studies should be necessary on the health effects by the THS exposures as well as malfodor of THS as a new type of passive smoking issue.

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