Personal exposure to air pollution and respiratory health of COPD patients in London

Previous studies have investigated the effects of air pollution on chronic obstructive pulmonary disease (COPD) patients using either fixed site measurements or a limited number of personal measurements, usually for one pollutant and a short time period. These limitations may introduce bias and distort the epidemiological associations as they do not account for all the potential sources or the temporal variability of pollution.We used detailed information on individuals’ exposure to various pollutants measured at fine spatio-temporal scale to obtain more reliable effect estimates. A panel of 115 patients was followed up for an average continuous period of 128 days carrying a personal monitor specifically designed for this project that measured temperature, PM10, PM2.5, NO2, NO, CO and O3 at one-minute time resolution. Each patient recorded daily information on respiratory symptoms and measured peak expiratory flow (PEF). A pulmonologist combined related data to define a binary variable denoting an “exacerbation”. The exposure-response associations were assessed with mixed-effects models.We found that gaseous pollutants were associated with a deterioration in patients’ health. We observed an increase of 16.4% (95% confidence interval: 8.6–24.6%), 9.4% (5.4–13.6%) and 7.6% (3.0–12.4%) in the odds of exacerbation for an interquartile range increase in NO2, NO and CO respectively. Similar results were obtained for cough and sputum. O3 was found to have adverse associations with PEF and breathlessness. No association was observed between particles and any outcome.Our findings suggest that, when considering total personal exposure to air pollutants, mainly the gaseous pollutants affect COPD patients’ health.

Passive-Type Radon Monitor Constructed Using a Small Container for Personal Dosimetry

The International Commission on Radiological Protection (ICRP) recently recommended a new dose conversion factor for radon based on the latest epidemiological studies and dosimetric model. It is important to evaluate an inhalation dose from radon and its progeny. In the present study, a passive radon personal monitor was designed using a small container for storing contact lenses and its performance was evaluated. The conversion factor for radon (222Rn), the effect of thoron (220Rn) concentration and the air exchange rate were evaluated using the calibration chamber at Hirosaki University. The minimum and maximum detectable radon concentrations were calculated. The conversion factor was evaluated as 2.0 ± 0.3 tracks cm−2 per kBq h m−3; statistical analyses of results showed no significant effect from thoron concentration. The minimum and maximum detectable radon concentrations were 92 Bq m−3 and 231 kBq m−3 for a measurement period of three months, respectively. The air exchange rate was estimated to be 0.26 ± 0.16 h−1, whose effect on the measured time-integrated radon concentration was small. These results indicate that the monitor could be used as a wearable monitor for radon measurements, especially in places where radon concentrations may be relatively high, such as mines and caves.

Air Pollution Exposure Monitoring among Pregnant Women with and without Asthma

Background: We monitored exposure to fine particulates (PM2.5), ozone, nitrogen dioxide (NO2), and ambient temperature for pregnant women with and without asthma. Methods: Women (n = 40) from the Breathe—Well-Being, Environment, Lifestyle, and Lung Function Study (2015–2018) were enrolled during pregnancy and monitored for 2–4 days. Daily pollutants were measured using personal air monitors, indoor air monitors, and nearest Environmental Protection Agency’s stationary monitors based on GPS tracking and home address. Results: Personal-monitor measurements of PM2.5, ozone, and NO2 did not vary by asthma status but exposure profiles significantly differed by assessment methods. EPA stationary monitor-based methods appeared to underestimate PM2.5 and temperature exposure and overestimate ozone and NO2 exposure. Higher indoor-monitored PM2.5 exposures were associated with smoking and the use of gas appliances. The proportion of waking-time during which personal monitors were worn was ~56%. Lower compliance was associated with exercise, smoking, being around a smoker, and the use of a prescription drug. Conclusions: Exposure did not vary by asthma status but was influenced by daily activities and assessment methods. Personal monitors may better capture exposures but non-compliance merits attention. Meanwhile, larger monitoring studies are warranted to further understand exposure profiles and the health effects of air pollution during pregnancy.

Pilot Study of the Use of Personal Carbon Monoxide Monitoring to Achieve Radical Smoking Reduction

Background and aims: This study examined whether providing smokers with a personal monitor for measuring expired-air carbon monoxide (CO) concentrations would be a feasible method of achieving a reduction in smoke intake. Methods: Ten smokers were given a CO monitor and asked to use it regularly throughout the day for 6 weeks with the aim of maintaining their CO reading below 10 ppm. They were advised to use nicotine replacement therapy, but this was not provided. At baseline and follow-up, smokers were asked to comment on their use of the monitors and motivation to stop smoking. Demographic characteristics, cigarette consumption, and nicotine dependence, was also assessed. Additionally, during the first 2 weeks participants were instructed to record how often they used their CO monitor, their average readings and cigarette consumption. Results: Eight smokers had an average daily CO concentration below their baseline on at least 93% of the days in the 2 weeks of daily monitoring, while three had CO levels below 10 ppm on 36% of the days. At the 6-week follow-up, all participants’ CO concentrations were below their baseline value; two were below 10 ppm. Average daily cigarette consumption reduced from 14.1 (SD 6.03) at baseline to 9.8 (SD 4.95) during the 2 weeks of daily CO monitoring (t = 2.46, df 9, p = 0.036) and 9.5 (SD 5.50) at 6 weeks follow-up (t = 1.73, df 7, p = 0.127). Use of the CO monitors was generally found to be acceptable and to increase motivation to stop smoking completely. Five smokers attempted to quit smoking. Conclusions: Regular personal CO monitoring may be a useful method for reducing smokers’ cigarette intake and increasing their motivation to stop completely. A controlled trial with long-term follow up is warranted.