Exposure Of Users Research Articles

Comparison of sampling methods for the determination of volatile organic compounds in consumer aerosol sprays

Many studies have evaluated the hazardous substances contained in various household chemical products. However, for aerosol spray products there is currently no international standard sampling method for use in a component analysis. The aim of this study was to develop an appropriate sampling method for the analysis of volatile organic compounds (VOCs) in consumer aerosol sprays. Two different sampling methods, spraying (into a vial) and perforating (and transferring the contents into a vial), were used to evaluate the levels of 16 VOC components in eight different aerosol spray products. All eight products contained trace amounts of hazardous VOCs, and a quantitative analysis showed that, for the same product, VOC concentrations were higher when spraying than when perforating. Using the spraying method, average toluene, ethylbenzene, p-xylene, o-xylene, and styrene concentrations were 1.80-, 2.10- 2.25-, 2.03-fold, and 1.28-fold higher, respectively, than when using the perforating method. The spraying method may provide more realistic estimates of the user's exposure to harmful substances and the associated health risks when using spray products. Of the two representative methods widely used to analyze harmful substances in consumer aerosol sprays, the spraying method is recommended over the perforating method for the analysis of VOCs.

Cyberbullying in text content detection: an analytical review

Technological advancements have resulted in an exponential increase in the use of online social networks (OSNs) worldwide. While online social networks provide a great communication medium, they also increase the user's exposure to life-threatening situations such as suicide, eating disorder, cybercrime, compulsive behavior, anxiety, and depression. To tackle the issue of cyberbullying, most existing literature focuses on developing approaches to identifying factors and understanding the textual factors associated with cyberbullying. While most of these approaches have brought great success in cyberbullying research, data availability needed to develop model detection remains a challenge in the research space. This paper conducts a comprehensive literature review to provide an understanding of cyberbullying detection.

Real-time monitoring of the emission of volatile organic compounds from polylactide 3D printing filaments

Establishing the emission profile of volatile organic compounds generated during fused deposition modeling 3D printing using polymer filaments is important in terms of both understanding the processes taking place during thermal degradation of thermoplastics, and assessing the user's exposure to potentially harmful volatiles. However, obtaining detailed, real-time qualitative and quantitative results poses a challenge. In this paper solid-phase microextraction-gas chromatography-time-of-flight mass spectrometry and proton transfer reaction time-of-flight mass spectrometry were used to identify and monitor the emission of volatiles during thermal degradation of polylactide filaments and during 3D printing. Filaments of two different grades and three colours were used. It was possible to obtain detailed, time- and temperature-resolved emission profiles of the main products of thermal decomposition of lactide and polylactide 3D printing filaments at concentration levels of a few μg/g. This revealed different temperature-dependent emission characteristics of particular volatiles, such as, among others, lactide, acetaldehyde, acetic acid, and 2-butanone between various polylactide 3D printing filaments. This approach can be used to monitor the emission associated with printing with various other types of polymer 3D printing materials.

Disconfirmation effect on online review credibility: An experimental analysis

The rise of e-commerce has led to the increased reliance of users on electronic word-of-mouth (eWOM) to evaluate the products and services offered. Previous research has attempted to determine which reviews are more credible than others, as credible reviews tend to impact readers more than non-credible ones. However, one of the research questions in this domain that has not been addressed so far is the impact of circumstances of review writing itself, which may influence the way the review is written and affect its credibility. In this paper, we describe a controlled experiment to study the impacts of a user's exposure to past reviews and the user's own product experience on the perceived credibility of reviews written by the user. We have employed attitude-behavior linkage theories and the disconfirmation effect to study this phenomenon. Our results indicate that disconfirmation, or the difference between a user's own experience and expected experience, has a significant impact on the way a user writes reviews and hence on the review's perceived credibility with the subsequent readers of the review. We find that disconfirmation and perceived review credibility follow a U-shaped relationship, in which perceived credibility is high for the highest and lowest values of disconfirmation.

The influence of thermal comfort conditions on user's exposure time in open spaces.

This paper discusses the influence of the user thermal comfort conditions on the time spent in open spaces through a case study performed in Bauru, Sao Paulo, Brazil. The study was carried out in two subspaces of a zoo, under warm and wet conditions. Although the subspaces had different levels of shading, they were of similar interest to visitors. The methodology adopted the collection of objective (air and globe temperature, humidity, and velocity) and subjective data (by application of questionnaires), for a sample of 174 users, and local observations with photographic records each 3min. Data and images obtained enabled the characterization of the local microclimates and contributed to evaluate (1) user's thermal perception (7-point scale), (2) affective evaluation of the thermal comfort (4-point scale), (3) thermal preference (7-point scale), (4) calculated thermal perception (through PET (physiological equivalent temperature) index), and (5) user's exposure time in each subspace. The great contributions of this work were to identify that in the subspace with bigger shading and less rigorous microclimatic conditions, users had exposure time longer than another more exposed to solar radiation and to validate a method to measure user's exposition time through sequential photos. These results contribute to a discussion that has yet been little explored in the literature of the area, proving the strong influence of the thermal comfort conditions in the users' exposure time in open spaces.

Design and Validation of a Research-Grade Waterpipe Equipped With Puff Topography Analyzer.

Worldwide, commercially available waterpipes vary widely in design and durability, including differences in fabrication materials, degree of leak-tight fit, and flow path diameter. Little is known about how the components of the waterpipe may influence puffing behavior and user's exposure to toxins. To systematically evaluate exposure, it is necessary to use a standardized research-grade waterpipe (RWP) when conducting clinical and laboratory-based trials. We developed a RWP that is configured with an in-line topography system which allows real-time measurement and recording of the smoke volume drawn through the RWP. The RWP was calibrated across the flow rate range expected for waterpipe tobacco smoking and the calibration was verified for known puff volumes using a smoking machine. Operation of the RWP was qualified in a cohort of experienced waterpipe smokers, each smoker using the RWP ad libitum in a laboratory setting while smoker topography and subjective effects data were collected. RWP machine smoking was highly reproducible and yielded puff volumes that agreed well with true values. User acceptance was comparable, and puffing behavior was similar in pattern, with more frequent puffing in the beginning of the session, but significantly different in intensity from that used to estimate the majority of toxicant exposure reported in the literature. The RWP operates with known precision and accuracy and is well accepted by experienced smokers. This tool can be used to determine the extent to which puffing behaviors are affected by the waterpipe design, components, and/or accessories, tobacco nicotine content, sweet flavorings and/or additives known to increase addictiveness. This study describes a standardized RWP, equipped with a puffing topography analyzer, which can operate with known precision and accuracy, and is well-accepted by experienced smokers in terms of satisfaction and reward. The RWP is an important tool for determining if puffing behaviors, and thus estimated toxin exposures, are affected by the waterpipe design, components, and/or accessories, tobacco nicotine content, sweet flavorings, and/or additives that are known to increase addictiveness.

Assessment of real exposure to GSM mobile telephones using the SYRPOM

A mobile telephone user's exposure to the radio-frequency electromagnetic field depends heavily on the power their telephone radiates, which can vary widely according to requests from the base station. This study presents the design and development of a system called SYstem for Radiated POwer Measurement (SYRPOM), which measures the power radiated by a mobile telephone. This study also describes the tests carried out on the system itself and gives the results of two measuring campaigns it has been possible to perform in this way. The first such campaign consisted of assessing the mean power received by a typical mobile telephone user carrying out various activities. The second campaign was aimed at (1) comparing the mean radiated power when stationary and when moving and (2) assessing and contrasting different models of handsets in terms of the mean radiated power. The SYRPOM has proved to be a flexible, easy-to-use high-performance and innovative tool for carrying out this kind of studies.

What is the biological fate of mentholated cigarette smoking?

What is the biological fate of mentholated cigarette smoking?

Ozone emissions from a "personal air purifier".

Ozone emissions were measured above a "personal air purifier" (PAP) designed to be worn on a lapel, shirt pocket, or neck strap. The device is being marketed as a negative ion generator that purifies the air. However, it also produces ozone within the person's immediate breathing zone. In order to assess worst-case potential human exposure to ozone at the mouth and nose, we measured ozone concentrations in separate tests at 1, 3, 5, and 6 in. above each of two PAPs in a closed office. One PAP was new, and one had been used slightly for 3 months. Temperature, relative humidity, atmospheric pressure, room ozone concentration, and outdoor ozone concentration also were measured concurrently during the tests. Average ozone levels measured directly above the individual PAPs ranged from 65-71 ppb at 6 in. above the device to 268-389 ppb at 1 in. above the device. Ozone emission rates from the PAPs were estimated to be 1.7-1.9 microg/minute. When house dust was sprinkled on the top grid of the PAPs, one showed an initial peak of 522 ppb ozone at 1 in., and then returned to the 200-400 ppb range. Room ozone levels increased by only 0-5 ppb during the tests. Even when two PAPs were left operating over a weekend, room ozone levels did not noticeably increase beyond background room ozone levels. These results indicate that this "PAP," even without significant background ozone, can potentially elevate the user's exposures to ozone levels greater than the health-based air quality standards for outdoor air in California (0.09 ppm, 1-hour average) and the United States (0.08 ppm, 8-hour average).

Intrauterine contraceptive device and pelvic inflammatory disease.

Comprehensive, mainly epidemiological data has helped us to recognize the strongest risk factors of pelvic inflammatory disease during intrauterine contraceptive device use. These are user's exposure to sexually transmitted diseases, young age and insertion of the device. Moreover, parity of the user and type of device may affect the risk of pelvic infection.