Inhalation of ash can be of great concern for affected communities, during and after volcanic eruptions. Governmental and humanitarian agencies recommend and distribute a variety of respiratory protection (RP), most commonly surgical masks. However, there is currently no evidence on how effective such masks are in protecting wearers from volcanic ash. In Part I of this study (Mueller et al., 2018), we assessed the filtration efficiency (FE) of 17 materials from different forms of RP against volcanic ash and a surrogate, low-toxicity dust, Aloxite. Based on those results, we now present the findings from a volunteer simulation study to test the effect of facial fit through assessment of Total Inward Leakage (TIL). Four different disposable RP types that demonstrated very high median FE (>= 96% for Aloxite; >= 89% for volcanic ash) were tested without provision of training on fit. These were an industry-certified mask (N95-equiv.); a surgical mask from Japan designed to filter PM2.5; a flat-fold basic mask from Indonesia; and a standard surgical mask from Mexico, which was also tested with an added medical bandage on top, as an additional intervention to improve fit. Ten volunteers (6 female, 4 male) were recruited. Each RP type was worn by volunteers under two different conditions simulating cleaning-up activities during/after volcanic ashfall. Each activity lasted 10 min and two repeats were completed for each RP type per activity. Dust (as PM2.5) concentration inside and outside the mask was measured with two TSI SidePak aerosol monitors (Models AM510 and AM520, TSI, Minnesota, USA) to calculate TIL. A questionnaire was administered after each test to collect perceptions of fit, comfort, protection and breathability. The best-performing RP type, across both activities, was the industry-certified N95-equiv. mask with 9% mean TIL. The standard surgical mask and the basic flat-fold mask both performed worst (35% TIL). With the additional bandage intervention, the surgical mask mean TIL improved to 24%. The PM2.5 surgical mask performed similarly, with 22% TIL. The N95-equiv. mask was perceived to provide the best protection, but was also perceived as being uncomfortable and more difficult to breathe through. This study provides a first objective evidence base for the effectiveness of a selection of RP types typically worn around the world during volcanic crises. The findings will help agencies to make informed decisions on the procurement and distribution of RP in future eruptions.

Objectives Many residents in Beijing use disposable face masks in an attempt to protect their health from high particulate matter (PM) concentrations. Retail masks may be certified to local or international standards, but their real-life performance may not confer the exposure reduction potential that is marketed. This study aimed to evaluate the effectiveness of a range of face masks that are commercially available in China. Methods Nine masks claiming protection against fine PM (PM2.5) were purchased from consumer outlets in Beijing. The masks’ filtration efficiency was tested by drawing airborne diesel exhaust through a section of the material and measuring the PM2.5 and black carbon (BC) concentrations upstream and downstream of the filtering medium. Four masks were selected for testing on volunteers. Volunteers were exposed to diesel exhaust inside an experimental chamber while performing sedentary tasks and active tasks. BC concentrations were continuously monitored inside and outside the mask. Results The mean per cent penetration for each mask material ranged from 0.26% to 29%, depending on the flow rate and mask material. In the volunteer tests, the average total inward leakage (TIL) of BC ranged from 3% to 68% in the sedentary tests and from 7% to 66% in the active tests. Only one mask type tested showed an average TIL of less than 10%, under both test conditions. Conclusions Many commercially available face masks may not provide adequate protection, primarily due to poor facial fit. Our results indicate that further attention should be given to mask design and providing evidence-based guidance to consumers.

During volcanic eruptions and their aftermath, communities may be concemed about the impacts of inhaling volcanic ash. Access to effective respiratory protection (RP) is therefore important for many people in volcanic areas all over the world. However, evidence to support the use of effective RP during such crises is currently lacking. The aim of this study was to build the first evidence base on the effectiveness of common materials used to protect communities from ash inhalation in volcanic crises. We obtained 17 forms of RP, covering various types of cloth through to disposable masks (typically used in occupational settings), which communities are known to wear during volcanic crises. The RP materials were characterised and subjected to filtration efficiency (FE) tests, which were performed with three challenge dusts: ashes from Sakurajima (Japan) and Soufriere Hills (Montserrat) volcanoes and aluminium oxide (Aloxite), chosen as a low-toxicity surrogate dust of similar particle size distribution. FE tests were conducted at two concentrations (1.5 mg/m(3) and 2.5 mg/m(3)) and two flow rates (equivalent to 40 and 801/min through 15.9 cm(2) sections of each RP type). Each material was held in a sample holder and PM2.5 dust concentrations were measured both outside the mask material and inside the sample holder to determine FE. A limited number of tests were undertaken to assess the effect on FE of wetting a bandana and a surgical mask, as well as folding a bandana to provide multiple filter layers. Overall, four RP materials performed very well against volcanic ash, with median FEs in excess of 98% (N95-equiv., N99-equiv., PM2.5 surgical (Japan), and Basic flat-fold (Indonesia)). The two standard surgical masks tested had median FEs of 89-91%. All other materials had median FEs ranging from 23 to 76% with no cloth materials achieving > 44%. Folding a bandana resulted in better FE (40%; 3 x folded) than single-layered material (29%). Wetting the bandana and surgical mask material did not improve FE overall. This first evidence base on the FE of common materials used to protect communities in volcanic crises from ash inhalation has been extended in a companion study (Steinle et al., 2018) on the total inward leakage of the best-performing masks when worn by human volunteers. This will provide a complete assessment of the effectiveness of these RP types.

Objective To determine if a low-cost particle counter, the Dylos DC 1700, can be used in homes to quantify second-hand smoke (SHS) concentrations.Methods Participants were recruited from a hospital-based study of attitudes on smoking. Two photometric devices (Dylos DC1700 and Sidepak AM510 Personal Aerosol Monitor) capable of measuring and logging concentrations of particulate matter were placed in smoking and non-smoking homes for approximately 24h. Acquired data were randomly allocated to one of two groups: one was used to generate a calibration equation using regression techniques; the second was used for validation of the generated model. The mean difference and limits of agreement between the two instruments were calculated using the validation dataset. Summary air-quality results were also compared across the entire dataset.Results Over 500 001 minute concentration measurements were collected from 34 homes. 25 301 randomly selected paired-measurements were used to generate a calibration equation (R-2 0.86) converting the particle number concentration from the Dylos to a mass concentration of PM2.5 as measured by the Sidepak. The mean difference (limits of agreement) between the remaining 25 102 paired measurements was -0.09 (-49.7 to 49.5) with 3.2% of values outside the limits of agreement. Differences in the air quality information generated by the two instruments were generally small and unlikely to impact on user interpretation.Conclusions The Dylos appears to be a valid instrument for measuring PM2.5 in household settings. The Dylos may be useful in air quality-based interventions designed to change smokers' behaviours with the possibility of encouraging cessation and/or smoke-free homes.

Indoor combustion of solid biomass fuels such as wood and charcoal is common in large parts of the world and has been demonstrated to lead to high levels of exposure to fine particulate matter and gases such as carbon monoxide. Such exposures have been shown to be linked to increased risk of respiratory and cardiovascular illness and may contribute to as many as 2 million early deaths globally per annum. There are a range of interventions currently being trialled including improved cookstoves and changes in fuel type. Small household biogas digesters are now available and are likely to have the capacity to significantly reduce household concentrations of respirable particulate matter and carbon monoxide. Although no direct evidence is available, comparison with households using Liquified Petroleum Gas (LPG) would suggest that improvements in indoor air quality may be of the order of 66–99%. Such improvements in households taking up this technology could bring respiratory and cardiovascular health benefits of the order of 20–25% reduction in risk of a wide range of diseases. There is a need for well-designed longitudinal studies to examine the impact of introducing biogas digesters to communities on both exposure to indoor air pollution and the health effects this may bring.

OBJECTIVE:Using data on fine particulate matter less than 2.5 μm (PM2.5) concentrations in smoking and non-smoking homes in Scotland to estimate the mass of PM2.5 inhaled by different age groups. METHODS:Data from four linked studies, with real-time measurements of PM2.5 in homes, were combined with data on typical breathing rates and time-activity patterns. Monte Carlo modelling was used to estimate daily PM2.5 intake, the percentage of total PM2.5 inhaled within the home environment and the percentage reduction in daily intake that could be achieved by switching to a smoke-free home. RESULTS:Median (IQR) PM2.5 concentrations from 93 smoking homes were 31 (10-111) μg/m(3) and 3 (2-6.5) μg/m(3) for the 17 non-smoking homes. Non-smokers living with smokers typically have average PM2.5 exposure levels more than three times higher than the WHO guidance for annual exposure to PM2.5 (10 μg/m(3)). CONCLUSIONS:Fine particulate pollution in Scottish homes where smoking is permitted is approximately 10 times higher than in non-smoking homes. Taken over a lifetime many non-smokers living with a smoker inhale a similar mass of PM2.5 as a non-smoker living in a heavily polluted city such as Beijing. Most non-smokers living in smoking households would experience reductions of over 70% in their daily inhaled PM2.5 intake if their home became smoke-free. The reduction is likely to be greatest for the very young and for older members of the population because they typically spend more time at home.

The aims of the present study were to measure domestic PM 2.5 exposure and explore relationships with indices of asthma severity and control in children prescribed inhaled corticosteroids (ICSs). Disease severity was determined by questionnaire and spirometry. Asthma control was assessed by 5-day peak flow variability (PFV) and children's asthma control test (CACT) on the 1st and 5th day of peak flow testing. Concentrations of PM 2.5 were measured over a 24-h period. Twenty-two children were recruited, mean age 11.0 years. Across the 22 homes the median time weighted average (TWA) PM 2.5 concentration (range) was 7.4 μg/m 3 (2.0–150.0) and was significantly higher in the seven homes where smoking was reported (24.0 μg/m 3 ) than non-smoking homes (6.0 μg/m 3 ), p=0.001. There was a positive association between TWA PM 2.5 and PFV (rho = 0.55, p = 0.015, n = 19) and a negative association between TWA PM 2.5 and CACT (rho = − 0.56, p = 0.010, n = 20). TWA PM 2.5 exposure was not related to indices of asthma severity. Peak PM 2.5 concentration was not associated with any outcome. This exploratory study suggests that even at relatively low concentrations, there is an exposure–response relationship between increasing indoor air PM 2.5 concentrations and poorer asthma control in children prescribed ICSs.

Objective To measure levels of fine particulate matter in the rear passenger area of cars where smoking does and does not take place during typical real-life car journeys.Methods Fine particulate matter (PM2.5) was used as a marker of secondhand smoke and was measured and logged every minute of each car journey undertaken by smoking and non-smoking study participants. The monitoring instrument was located at breathing zone height in the rear seating area of each car. Participants were asked to carry out their normal driving and smoking behaviours over a 3-day period.Results 17 subjects (14 smokers) completed a total of 104 journeys (63 smoking journeys). Journeys averaged 27 min (range 5-70 min). PM2.5 levels averaged 85 and 7.4 mu g/m(3) during smoking and non-smoking car journeys, respectively. During smoking journeys, peak PM2.5 concentrations averaged 385 mu g/m(3), with one journey measuring over 880 mu g/m(3). PM2.5 concentrations were strongly linked to rate of smoking (cigarettes per minute). Use of forced ventilation and opening of car windows were very common during smoking journeys, but PM2.5 concentrations were still found to exceed WHO indoor air quality guidance (25 mu g/m(3)) at some point in the measurement period during all smoking journeys.Conclusions PM2.5 concentrations in cars where smoking takes place are high and greatly exceed international indoor air quality guidance values. Children exposed to these levels of fine particulate are likely to suffer ill-health effects. There are increasing numbers of countries legislating against smoking in cars and such measures may be appropriate to prevent the exposure of children to these high levels of secondhand smoke.

Objective To determine current secondhand smoke (SHS) concentrations in bars previously assessed as part of an evaluation of Scottish smoke-free legislation 5 years ago. Design Comparison between SHS levels measured in 2006 and 2011 in 39 pubs in 2 Scottish cities.Methods Fine particulate matter (PM2.5) was measured discreetly for 30 min in each bar on one or two visits 5 years after the previous visit in May/June 2006. These 5-year follow-up visits were undertaken on the same day of the week and at approximately the same time of day.Results Average PM2.5 levels measured in a total of 51 bar visits in 2011 were 12 mu g/m(3) (range 2-155 mu g/m(3)) compared to 20 mu g/m(3) (range 6-104 mu g/m(3)) in the period immediately after the ban in 2006. Fine particulate concentrations in all but two visits in 2011 were comparable to PM2.5 levels measured in outside ambient air on the same day, with 92% of visits (n = 47) providing 30-min average PM2.5 concentrations less than 25 mu g/m(3).Conclusions These results are one of the longest follow-up of any national smoke-free legislation and indicate that, 5 years after introduction, compliance is high and that the legislation continues to provide bar workers and non-smoking customers protection from SHS.

OBJECTIVE:To compare the response of a new particle counting instrument (Dylos DC1700) with that produced by a device (TSI Sidepak Personal Aerosol Monitor AM510) commonly used to measure PM2.5 in settings where secondhand smoke (SHS) is encountered.METHODS:Controlled chamber experiments with different SHS concentrations were generated by burning a cigarette for varying time periods and running both devices simultaneously.RESULTS:The Dylos and Sidepak devices produced similar responses to changes in SHS concentrations up to 1000 μg/m(3). Using 591 min of contemporaneous measurements from 13 chamber experiments, an equation was developed to allow conversion of particle number concentration data from the Dylos to estimated mass concentration data for SHS aerosol.CONCLUSIONS:The Dylos DC1700 can provide real-time data that may be converted to an estimate of SHS levels in smoky environments. Given the low cost, low noise and simplicity of use, this device is likely to be a useful tool for interventions to provide feedback of SHS concentrations to help motivate changes in smoking behaviour at home.

There is a widespread but unsubstantiated belief that the practice of smoking shisha products is relatively safe, which has led to resurgence in its use. This study aimed to characterise the mainstream smoke composition of three popular smoking products for shisha:, two that contain tobacco and one herbal, a tobacco-free product. A smoking machine was used to generate mainstream smoke from shisha in a series of controlled experiments using the three shisha smoking products. Each smoking session lasted 30 minutes and used 10g shisha product. The mainstream smoke was sampled and analysed for selected metals, nicotine, carbon monoxide (CO) and selected polycyclic aromatic hydrocarbons (PAHs). The particle size distribution of the shisha smoke was also determined. Levels for most metals in the mainstream smoke were found to be lower, or close to, the limit of detection (LOD) for all three smoking products. The main exceptions were copper (total yield of 1.3 and 2.3μg for the two tobacco-containing mixtures and 1.7μg for the herbal tobacco-free product) and zinc (yield ranged from 1.1μg for a tobacco-containing mixture to 2.1μg for the herbal product). Nicotine yields for the two tobacco-containing mixtures averaged 316 and 339μg per smoking session. PAHs were detected for all three shisha products, although yields for PAHs were generally less than the LOD of <0.02μg; the highest levels were observed for acenaphthene with the herbal tobacco-free product (total yield 17.3μg). CO levels in the mainstream smoke ranged from 800 to 1000ppm, suggesting a typical CO yield of 30mg per smoking session. The mass median aerodynamic diameter of the mainstream smoke ranged from 100-150nm. Results from this study appear to be different compared to other published studies, which could be owing to a number of factors such as shisha product type, smoking behaviour and measurement methods.

Soil samples from sites around Libby, Montana, where tailings or waste from the vermiculite mine formerly operated by W.R. Grace & Co. were thought to have been deposited, have been tested. The tests examined airborne concentrations of fibre and respirable dust generated from the soils after drying and dispersion. Results showed that the concentration of all fibres, normalised to the mass concentration of respirable airborne dust, ranged from 0.01 fibres mL-1 per mg · m-3 to 6.8 fibres mL-1 per mg · m -3. The normalised asbestos fibre concentrations ranged from 0.00 to 1.41 asbestos fibres mL-1. The relative levels appeared to be consistent with the amount of fine fibre in the bulk soil samples. A synthetic soil sample tested under the same conditions gave results consistent with these and samples from previous work. The effect of moisture was examined with the synthetic soil and showed that 5% moisture substantially reduced dust and fibre emissions, and at 10% moisture content the dust and fibre emission was almost completely suppressed, reducing the airborne fibre levels by several orders of magnitude. The addition of 10% moisture to the Libby soil reduced airborne asbestos fibre concentrations to ∼4% of that from the dried dust. Finally, ambient airborne particulate dust concentrations in Libby are several orders of magnitude lower than the particulate (soil) dust levels observed in these tests. The data from these tests suggest that ambient air concentrations in Libby resulting from disturbance of soils will typically be more than 1000 times lower than those reported in this study.

Objectives The relationship between indoor air exposure to fine particulate (PM2.5) and asthma symptoms in children is uncertain. The aim of the present study was to relate PM2.5 exposure to indices of asthma severity and control. Methods Children with asthma were recruited. Disease severity was determined by questionnaire and spirometry. Asthma control was assessed by 5-day peak flow variability and children's asthma control test (CACT) on the first and fifth day of peak flow testing. Concentrations of PM2.5 were measured over a 24-h period in the living room and the child's bedroom. Results 22 children were recruited, mean age 11.0 years. Across the 22 homes the median time weighted average (TWA) PM2.5 concentration (range) in the living room was 7.4 mg/m3 (2.0–150.0) and for the bedroom was 5.6 (3.1, 11.1) mg/m3 (p=0.04 for comparison with living room). As expected, there was a significantly higher mean TWA PM2.5 in the living rooms and bedrooms of the seven homes where smoking was reported; 22.0 mg/m3 for living rooms in smoking homes and 4.7 mg/m3 for non-smoking homes, p=0.001. There was a positive association between TWA PM2.5 in the living room and peak flow variability (r=0.51, p=0.027, see Abstract P77 Figure 1) and a negative association between TWA PM2.5 in the living room and CACT on day 5 (r=−0.48, p=0.037). TWA PM2.5 exposure was not related to indices of asthma severity including FEV1 and treatment. Peak PM2.5 concentration was not associated with any outcome.Abstract P77 Figure 1 Conclusions This small study suggests that even at relatively low concentrations, there is an exposure-response relationship between increasing indoor air PM2.5 concentrations, increased airway variability and poorer asthma control in children.

Second-hand tobacco smoke (SHS) exposure generates a large public health burden. Recent legislation has moved to prohibit smoking in public places and there are concerns that this may lead to an increase in exposures in private homes. Measurement of SHS aerosol has tended to use active pumped samples or longer-term diffusive badges. Pumped methods are noisy and poorly tolerated in home settings while diffusive badges do not provide real-time data. The UCB particle monitor (UCB-PM) is a modified smoke-alarm device capable of logging changes in airborne particulate matter over extended periods and has been used successfully to measure biomass fuel smoke concentrations in developing world settings This study has examined the use of the UCB-PM to measure SHS aerosol in both controlled laboratory conditions and a pilot field trial over a 7 day period in a smoker's home. Comparisons with a pumped sampler (TSI Sidepak Personal Aerosol Monitor) indicate good agreement over a range of exposure concentrations but there is evidence of a threshold effect at approximately 0.5 mg/m(3) of fine particulate measured as PM(2.5). While this threshold effect undermines the ability of the device to provide useful data on the time-weighted average SHS concentration, the field trial indicates that that the UCB-PM has a sensitivity of about 71% and a specificity of 98%. The device has many advantages including zero noise operation, low cost and long battery life and may be a useful tool in quitting and smoke-free home intervention studies.

In the UK, approximately 30% of cases of dermatitis reported to the national surveillance scheme are associated with wet working or exposure to aqueous mixtures. There is evidence that the duration and frequency that hands are wet are key determinants of risk, but there are no objective methods to measure these exposure factors. This research aimed to develop a practical tool to measure the duration and the number of occasions hands are wet. We developed an electronic sensor that is worn on the finger, which detects wetness from evaporative cooling. The output signal is recorded in electronic memory and the frequency and duration of exposure calculated using a simple data processing algorithm. The device has been tested in a variety of environmental conditions and for a standardized wet-work task. Wetting events were detectable in all the standardized tests, with the proportion of time the hands were wet ranging from 15 to 49% (mean 30%). The electronic sensor is slightly affected by abrupt changes in air temperature and rapid air movements, but these do not seem to impose any practical limitations. This IOM Wet-Work sampler has the potential to provide reliable measurements of exposure that may be used to assess the risk of contact dermatitis.

This report will comprise suggestions of links with other work and possible approaches for taking the work forward, providing a map of current and recent air quality related Citizen Science activities in the UK, Europe and beyond. In this deliverable, we map out the technologies and approaches currently available for air quality monitoring and provide an overview on how they could be applied in a citizen science context. In addition, we provide an overview of existing citizen science activities with relevance to air pollution. The focus of this report will be on the specific aspects of air pollution monitoring in a citizen science context; we refer to Roy et al. (2012) for a more general discourse on citizen science projects. As far as possible, we will closely link to another SEPA funded project with a focus on citizen science for environmental monitoring (by direct personal contact with colleagues at CEH), as well as other ongoing and emerging projects (e.g. EU FP7 project CitiSense, Transport Scotland, etc.). The objective of this report is not to draw final conclusions, but to provide the material and information resources for the following phases 2 and 3 of the pilot project.