Nasal Air Samplers Research Articles

Detection of Influenza Infection by IMS of Nasal Air Sampling

Detection of Influenza Infection by IMS of Nasal Air Sampling

NIAID, NIEHS, NHLBI, and MCAN Workshop Report: The indoor environment and childhood asthma—implications for home environmental intervention in asthma prevention and management

Environmental exposures have been recognized as critical in the initiation and exacerbation of asthma, one of the most common chronic childhood diseases. The National Institute of Allergy and Infectious Diseases; National Institute of Environmental Health Sciences; National Heart, Lung, and Blood Institute; and Merck Childhood Asthma Network sponsored a joint workshop to discuss the current state of science with respect to the indoor environment and its effects on the development and morbidity of childhood asthma. The workshop included US and international experts with backgrounds in allergy/allergens, immunology, asthma, environmental health, environmental exposures and pollutants, epidemiology, public health, and bioinformatics. Workshop participants provided new insights into the biologic properties of indoor exposures, indoor exposure assessment, and exposure reduction techniques. This informed a primary focus of the workshop: to critically review trials and research relevant to the prevention or control of asthma through environmental intervention. The participants identified important limitations and gaps in scientific methodologies and knowledge and proposed and prioritized areas for future research. The group reviewed socioeconomic and structural challenges to changing environmental exposure and offered recommendations for creative study design to overcome these challenges in trials to improve asthma management. The recommendations of this workshop can serve as guidance for future research in the study of the indoor environment and on environmental interventions as they pertain to the prevention and management of asthma and airway allergies.

Effect of a novel temperature-controlled laminar airflow device on personal breathing zone aeroallergen exposure.

Temperature-controlled laminar airflow improves symptoms in atopic asthmatics, but its effects on personal allergen exposure are unknown. We aimed to evaluate its effects on personal cat allergen and particulate exposures in a simulated bedroom environment. Five healthy volunteers lay under an active and an inactive temperature-controlled laminar airflow device for 175min, in a simulated bedroom containing bedding from a cat owner. Total airborne particles (≥0.5 - ≥10μm diameter) were quantified with a laser particle counter. Airborne allergen was sampled with Institute of Occupational Medicine filters. Inhaled exposure was sampled with nasal air samplers. Allergen-containing particles were quantified by immunoassay. Treatment reduced total airborne particles (>0.5μm diameter) by >99% (P<0.001) and reduced airborne allergen concentration within the breathing zone (ratio of median counts=30, P=0.043). Treatment reduced inhaled allergen (ratio of median counts=7, P=0.043). Treatment was not associated with a change in airborne allergen concentration outside of the breathing zone (P=0.160). Temperature-controlled laminar airflow treatment of individuals in an allergen-rich experimental environment results in significant reductions in breathing zone allergenic and non-allergenic particle exposure, and in inhaled cat allergen exposure. These findings may explain the clinical benefits of temperature-controlled laminar airflow.

Usefulness of a new malodour-compound detection portable device in oral malodour diagnosis

A new device (BB Checker®) able to detect malodour compounds has recently been made available. This retrospective analysis aimed at evaluating the usefulness of this device as adjunct tool for the diagnosis of oral malodour. Data from 100 consecutive volunteers with bad breath complaints attending their first consultation at a halitosis clinic were analysed. In addition to the standard protocol (organoleptic ratings from mouth and nose air, and from tongue coating when present; OralChroma™ and Halimeter® measurements from mouth air; and intra-oral examinations), oral, exhaled and nasal air samples were examined with the BB Checker®. We could not establish a correlation between the BB Checker® values and the organoleptic scores, or the sulfur-compound levels determined by the OralChroma™ or the Halimeter® (R < 0.3, p > 0.05). The overall sensitivity and specificity of the new device did not exceed the 50%. The correlations between the organoleptic scores and the OralChroma™ and the Halimeter® measurements were good and in line with previous reports (R between 0.56 and 0.73). Our results do not favour the use of the BB Checker® as adjunct tool in the diagnosis of oral malodour.

Personal exposure to grass pollen: relating inhaled dose to background concentration

BackgroundVery few studies on human exposure to allergenic pollen have been conducted using direct methods, with background concentrations measured at city center monitoring stations typically taken as a proxy for exposure despite the inhomogeneous nature of atmospheric pollen concentrations. A 2003 World Health Organization report highlighted the need for an improved understanding of the relation between monitoring station data and actual exposure. ObjectiveTo investigate the relation between grass pollen dose and background concentrations measured at a monitoring station, to assess the fidelity of monitoring station data as a qualitative proxy for dose, and to evaluate the ratio of dose rate to background concentration. MethodsGrass pollen dose data were collected in Aarhus, Denmark, in an area where grass pollen sources were prevalent, using Nasal Air Samplers. Sample collection lasted for approximately 25 to 30 minutes and was performed at 2-hour intervals from noon to midevening under moderate exercise by 2 individuals. ResultsA median ratio of dose rate to background concentration of 0.018 was recorded, with higher ratio values frequently occurring at 12 to 2 pm, the time of day when grass species likely to be present in the area are expected to flower. From 4 to 8 pm, dose rate and background concentration data were found to be strongly and significantly correlated (rs = 0.81). Averaged dose rate and background concentration data showed opposing temporal trends. ConclusionWhere local emissions are not a factor, background concentration data constitute a good quantitative proxy for inhaled dose. The present ratio of dose rate to background concentration may aid the study of dose–response relations.

London Plane Tree bioaerosol exposure and allergic sensitization in Sydney, Australia

Exposure to London Plane Tree (Platanus) bioaerosols in Sydney, Australia has been anecdotally linked to respiratory irritation, rhinitis, and conjunctivitis. To determine the relationships between Platanus bioaerosol exposure, allergic sensitization, and symptoms. Sixty-four subjects with self-reported Platanus symptoms were recruited from inner-urban Sydney. Allergic sensitization was determined by skin prick test (SPT) to 13 allergens. Airborne concentrations of Platanus pollen, trichomes, and achene fibers, and other pollen and fungal spores, were measured over the spring and summer of 2006-2007. Subjects' allergic symptoms were monitored concurrently. The Halogen immunoassay (HIA) was used to measure subjects' immunoglobulin E (IgE) reactivity to collected bioaerosols. Platanus pollen constituted 76% of total pollen between July 2006 and April 2007. Airborne concentrations of Platanus pollen peaked from August until October. Non-Platanus pollen peaked from July to December. Elevated concentrations of trichomes and achene fibers occurred from September to December and August to October, respectively. As determined by SPT, 85.9% of subjects were sensitized, 65.6% to any pollen tested, 56.3% to Lolium perenne, and 23.4% to Platanus. Higher mean daily symptom scores were only associated with high counts of non-Platanus pollens. HIA analysis demonstrated IgE binding to Platanus pollen in all Platanus sensitized subjects. Personal nasal air sampling detected airborne trichomes that were capable of being inhaled. Platanus trichomes or achene fibers did not bind IgE from any subject. Platanus bioaerosols exist in high concentrations between August and November in inner-urban Sydney but were not associated with seasonal symptoms. Platanus trichomes are inhaled and may constitute a respiratory irritant. Clinicaltrials.gov Identifier: NCTXXXXX.

P27 Personal allergen exposures are increased by changes in sleep position and improved by temperature-controlled laminar airflow

<h3>Introduction and Objectives</h3> Aeroallergens are released directly from bedding into the breathing zone, and contribute importantly to asthma symptoms. Adults change their sleep position between 3 and 45 times per night. The effect of these turns on inhaled particulate exposures is unknown. We aimed to investigate the effects of changing position on breathing zone particulate exposures and the effect of a novel Temperature-controlled Laminar Airflow (TLA) device on reducing such exposures. <h3>Methods</h3> A simulated bedroom was constructed containing bedding from a cat owner. Five healthy volunteers lay recumbent under an active and an inactive TLA device for 175 min. Volunteers made scheduled turns in bed to simulate normal sleep. Real-time total particle levels (≥0·5 μm diametre) within the breathing zone were measured by laser particle counting. Inhaled cat allergen exposure was measured by nasal air sampling. Time series analysis was used to evaluate changes in particulate exposures with turning. <h3>Results</h3> A greater proportion of larger particles than smaller ones were disturbed by turning over (F=20.6, df=5, p&lt;0.001). With the TLA switched off, 9% (95% CI 4 to 18) of total overhead particles &gt;10 μm diametre were accounted for by turning over, compared with 0.2% (95% CI 0.07 to 0.5) of particles &gt;0.5 μm diameter. TLA treatment reduced total particle numbers (size &gt;0.5 μm) by 3010-fold (p&lt;0.001) and significantly reduced the turn-associated increase for all particle sizes (Abstract P27 Figure 1, p&lt;0.015). Similar turn-associated increases in nasal air sampler cat particle counts were seen. TLA treatment reduced nasal cat allergen exposures by sevenfold (p=0.043). <h3>Conclusions</h3> Turning over in bed causes a significant increase in breathing zone exposures to particulates which are within the respirable size range. TLA treatment dramatically reduces overhead breathing zone total particulate exposures and also reduces nasal cat allergen exposure. TLA treatment attenuates the increase in particulate exposures caused by turning over. Treatments which result in better sleep quality and a reduced number of bodily turns may result in a reduction in personal breathing zone particulate exposures in bed.

Advances in environmental and occupational disorders 2006

In 2006, there continued to be significant contributions to the Journal in the area of environmental and occupational allergy. In addition to very strong clinical observations, there were a number of studies that examined the effect of environmental agents on cellular and molecular processes in allergy, and molecular approaches were also used in investigations of allergen structure and biology. The Journal also received a number of very strong epidemiologic studies examining several aspects of environmental and occupational allergy. Thus, this particular area of our specialty thrives as a result of clinical, mechanistic, epidemiologic, and translational observations. This article reviews a number of these papers presented in the Journal in 2006.

Nasal Air Sampling for Measuring Inhaled Wheat Allergen in Bakeries With and Without Facemask Use

Occupational asthma caused by flour is common in bakers. We applied novel intranasal air samplers (INAS) to assess wheat allergen exposure and evaluate respiratory protection in bakeries. Two models of INAS (INAS-M1 and INAS-M2) were compared with simultaneous personal air sampling of inhalable dust, both with and without facemasks. Wheat allergen levels were measured using a sensitive sandwich enzyme immunoassay. Allergenic particles were immunostained for microscopic visualization. Personal air sampling correlated well with INAS-M1 (r = 0.89) and INAS-M2 (r = 0.75). INAS-M2 collected particles more effectively than INAS-M1. Facemasks reduced inhalation of wheat allergen by 96% and 93% measured using INAS-M1 and INAS-M2, respectively. Nasal air sampling can complement personal air sampling to measure short-term exposure and evaluate respiratory protection. To prevent baker's asthma, facemasks may be an effective solution in addition to improving workplaces.

Intranasal air sampling in homes: Relationships among reservoir allergen concentrations and asthma severity

The relationship among inhaled allergen exposure, sensitization, and asthma severity is unknown. To investigate the relationship among personal allergen exposure, reservoir dust allergen concentrations, and physiological measures of asthma severity; to examine the numbers of particles inspired that react with autologous IgE and IgG4. A total of 117 patients with asthma wore 5 nasal air samplers (NASs) at home: 1 each for exposure to mite, cat and dog allergens, NAS-IgE, and NAS-IgG4. NASs were processed by HALOgen assay for allergen measurement and incubated with autologous serum for detection of NAS-IgE and NAS-IgG4. Reservoir allergen concentrations were measured by ELISA. Subjects' asthma severity was ascertained by measurement of lung function, exhaled nitric oxide, and nonspecific bronchial reactivity to histamine. Nasal air sampler counts correlated with reservoir concentrations for cat (r=0.31; P=.001) and dog (r=0.20; P=.03) but not mite allergen (r=0.001; P=1.0). There was no significant relationship between sensitization with exposure measured by NAS to any allergen and PD20FEV1 (F[3,60]=1.60; P=.20); however, sensitization with exposure in dust reservoirs had significant effects on PD20FEV1 for any allergen (F[3,59]=3.12; P=.03), cat (F[3,59]=3.77; P=.01), and mite (F[3,59]=2.78; P=.05), but not dog (F[3,59]=1.06; P=.37). We repeated the analysis with separate variables for sensitization and exposure, controlling for the confounders; sensitization but not exposure conferred lower PD20FEV1 values. However, increasing cat allergen exposure was associated with improving bronchial reactivity in not cat-sensitized patients. NAS-IgE and NAS-IgG4 counts bore no relationship to any measure of asthma severity. Nasal air samplers confer no advantage over reservoir dust analysis for studies of asthma severity. In common with other measures of exposure, single nasal air samples do not provide a useful measure of home allergen exposure for the individual patient with allergic asthma.

High‐efficiency vacuum cleaners increase personal mite allergen exposure, but only slightly

High-efficiency particulate-arrest-filter vacuum cleaners are recommended to allergy sufferers although their use increases personal cat allergen exposure. We aimed to measure personal mite allergen exposure during vacuum cleaning by nasal air sampling and to compare exposures while vacuuming and emptying the vacuum cleaner bag. Five brand new high-efficiency vacuum cleaners were selected. An old, previously used vacuum cleaner with its original microfilter in situ was used as a control. Nasal air samples were taken prior to and during vacuum cleaning in 10 homes. Samples were processed by HALOgen assay. Personal mite and cat allergen exposure was measured as the dust compartments were emptied. There was an increase in personal mite allergen exposure with vacuum cleaning, which approached significance (P = 0.058). There was no difference between the high-efficiency vacuum cleaners and the control vacuum cleaner (P = 0.141). When the dust compartments were emptied, personal mite and cat allergen exposure increased (P < 0.02). CONCLUSIONS. The increase in personal mite allergen exposure while vacuum cleaning in an area with mild to moderate mite allergen exposure is small. High-efficiency vacuum cleaners confer no benefit and cannot currently be recommended to allergy sufferers as a means of reducing personal mite allergen exposure.

Interpretation of pollen exposure data

Rationale Aerobiological sampling traditionally uses a spore trap located in a fixed location to estimate exposure to airborne pollens and fungi. We examined pollen counts made with a spore trap and personally worn pumps with the amount of pollens actually inhaled by people. Methods Pollen was collected with a Burkard spore trap (10L/min) in a park while 30 adult subjects used nasal air samplers (NAS) for 2 hours on 2 separate days. Four subjects also wore personal IOM filter samplers operating at 2 L/min. The NAS were previously shown to collect 97-99% of pollens. All subjects were in close proximity and performed similar low-level physical activities. Results Comparing counts for each day by each method indicated wide variation in the relative counts. Total pollen counts were higher on Day 2 compared to Day 1 for NAS, pump and spore trap by factors of 2.7, 1.7 and 5.5 fold respectively. On Day 2, inhaled geometric mean pollen counts over 2 hours by NAS were 53.4 (range 1-1699) for Ambrosia and 9.8 (range 2-32) for Poaceae pollen. The corresponding spore trap counts for this period were 93.5 Ambrosia and 44 Poaceae and mean personal IOM counts were 64 Ambrosia and 3 Poaceae. Conclusions The three methods gave markedly different relative counts from day to day. Personal exposure to pollen in people in the same location and performing similar activities can vary by 13-40 fold (5-95% percentiles).

The impact of bedding encasing on nocturnal Der p1 exposure and asthma

Rationale Our aims were to develop a short term sampling protocol for inhaled Der p1 that was representative of nocturnal exposure; and to examine the effect of encasing bedding on mite exposure and symptoms of asthma. Methods Mite exposure was measured using nasal air samplers (NAS) and anti-Der p1 staining with Halogen assay. Variation and repeatability of sampling was established by collecting 30 mins samples upon bed entry, at 2 and 4 hours after going to bed and on waking. In a separate study, 10 mite-allergic asthmatic subjects each collected 12 NAS samples upon bed entry over 4 weeks, then encased mattresses, pillows and duvets and collected 12 more samples over the next 4 weeks. Clinical outcomes were assessed during both periods. Results Inhaled mite allergen in the 30 minutes following bed entry significantly correlated with inhaled exposure throughout the night (R2=0.57, p=0.0001). Inhaled mite exposure was repeatable between sampling periods for each subject (ICC=0.65). Encasing bedding reduced mite allergen inhaled in bed by only 1.8 fold (p=0.007) and resulted in a significant reduction in asthma and allergy symptom scores (p=0.04 and p=0.02, respectively, paired T-test), but had no significant impact on peak flow, B2-agonist use, PD20/reversibility or FEV1. Conclusions Allergen inhaled in the first 30 minutes following bed entry is a predictor of exposure throughout the night. Encasing of bedding had a small but significant effect upon inhaled Der p1 and asthma and allergy symptoms but no effect on lung function measurements.

Trend for asthma severity to be associated with total aeroallergen exposure

Rationale We examined the relation of personal total aeroallergen exposure, measured using a novel self-administered method, to markers of asthma. Methods 80 subjects (69 with positive skin prick tests, SPT+ve) collected aeroallergen in their beds using nasal air samplers for 30 mins. Aeroallergen was estimated by Halogen assay using the subject's IgE to form immunostained halos around inhaled particles. The halos were counted and their density summed. Airway hyperresponsiveness (AHR) was assessed by histamine challenge and asthma was defined as recent wheeze + AHR. Bed dust was sampled with an electrostatic cloth and cat and mite allergens measured by ELISA. Results 90% of subjects had IgE halos to their own inhaled dust, including 10 of the 11 SPT -ve subjects. The median IgE-halo count per subject was 5 (IQR 2 to 9). In the SPT +ve group, a two-fold increase in IgE-halos was associated with a small, but not significant, increase in the risk of having asthma symptoms (OR=1.21, 95% CI=0.95–1.54), more severe asthma, or AHR (OR=1.28, 95% CI=0.90–1.81). Bed dust concentrations of cat and mite allergen were not significantly related to markers of asthma. However, there was a trend for higher mite allergen levels and lower cat allergen levels to be associated with more severe asthma. Conclusions There was a small and non-significant trend for several indices of asthma severity to be associated with the number of inhaled particles that immunostained with the subject's own IgE. This new method is promising but requires further development.

Air filtration units in homes with cats: can they reduce personal exposure to cat allergen?

Domestic air filtration units have previously been shown to cause a dramatic fall in airborne pet allergen levels in homes with pets. Clinical trials of air filtration units, however, have failed to reveal a significant beneficial effect. Personal pet allergen exposure during air filtration unit use has never been measured. To determine the effect of air filtration on inhaled cat allergen exposure in homes with cats. Nasal air samplers were worn to measure personal cat allergen exposure. The study was carried out in five homes with cats on 4 separate days examining four experimental conditions (cat absent or present, air filtration off or on). The two operators collected four baseline samples and two 15-min samples/h over three consecutive hours. Cat allergen-bearing particles were detected by immunoblotting and allergen concentrations measured by amplified enzyme-linked immunosorbent assay (ELISA). There was a significant reduction in the quantity of the inhaled Fel d 1 when the air cleaner was used with the cat in the room. Fel d 1 halo counts (detransformed means) were 29.3 at baseline, 11.8 after 1 h, 10.0 after 2 h and 14.1 after 3 h, with no change on control days (P = 1.00). With the cat elsewhere in the house, a marginal, but statistically significant reduction was observed only after 3 h with the use of air cleaner (Fel d 1 halo count: baseline 12.4; 3 h 5.5; P = 0.01). The use of air filtration units appears to result in a much smaller reduction of inhaled cat allergen exposure than suggested by previous studies using standard air samplers. Cat removal remains the best advice to cat-allergic patients who experience symptoms upon exposure.

High-efficiency particulate arrest–filter vacuum cleaners increase personal cat allergen exposure in homes with cats

Background: On the basis of experimental chamber studies, vacuum cleaners with double-thickness bags and integral high-efficiency particulate arrest (HEPA) air filters are claimed to reduce airborne allergen levels and are currently recommended to allergic patients. Objectives: The objective of this study was to investigate the effect of vacuum cleaning on personal inhaled cat allergen exposure in homes with cats. Methods: Five unused new vacuum cleaners were compared with an old non-HEPA filter vacuum cleaner. Each vacuum cleaner was tested in an experimental chamber and in 5 homes with cats. Inhaled cat allergen was measured by nasal air sampling. Results: New vacuum cleaners failed to leak any allergen in the experimental chamber. There was a significant increase in inhaled cat allergen during vacuum cleaning in homes (F = 48.39, df = 1.4, P = .002) with no difference between the old vacuum cleaner and the unused new vacuum cleaners (5-fold and 3-fold increase compared to baseline, respectively; F = 0.005, df = 1.4, P = .95). Conclusions: The use of new HEPA-filter vacuum cleaners increases inhaled cat allergen in homes with cats. The use of HEPA-filter modern vacuum cleaners to reduce pet allergen exposure in the homes of pet owners should not be justified merely on the basis of experimental chamber data.

The editors' choice

The inhalation of latex aeroallergens can induce respiratory and systemic responses and is a major concern among recognized risk groups. Poulos et al (p 701) used nasal air samplers to measure and compare the amounts of inhaled latex aeroallergen (Hev b 1) when latex gloves and latex-substitute (vinyl) gloves were worn. Surface contamination with latex allergen was also monitored. It was observed that subjects inhaled 26 times more allergen when powdered latex gloves were worn than when powdered vinyl gloves were worn.

Inhalation of nasally derived nitric oxide modulates pulmonary function in humans.

The vasodilator gas nitric oxide (NO) is produced in the paranasal sinuses and is excreted continuously into the nasal airways of humans. This NO will normally reach the lungs with inspiration, especially during nasal breathing. We wanted to investigate the possible effects of low-dose inhalation of NO from the nasal airways on pulmonary function. The effects of nasal and oral breathing on transcutaneous oxygen tension (tcPO2) were studied in healthy subjects. Furthermore, we also investigated whether restoring low-dose NO inhalation would influence pulmonary vascular resistance index (PVRI) and arterial oxygenation (PaO2) in intubated patients who are deprived of NO produced in the nasal airways. Thus, air derived from the patient's own nose was aspirated and led into the inhalation limb of the ventilator. In six out of eight healthy subjects tcPO2 was 10% higher during periods of nasal breathing when compared with periods of oral breathing. In six out of six long-term intubated patients PaO2 increased by 18% in response to the addition of nasal air samples. PVRI was reduced by 11% in four of 12 short-term intubated patients when nasal air was added to the inhaled air. The present study demonstrates that tcPO2 increases during nasal breathing compared with oral breathing in healthy subjects. Furthermore, in intubated patients, who are deprived of self-inhalation of endogenous NO. PaO2 increases and pulmonary vascular resistance may decrease by adding NO-containing air, derived from the patient's own nose, to the inspired air. The involvement of self-inhaled NO in the regulation of pulmonary function may represent a novel physiological principle, namely that of an enzymatically produced airborne messenger. Furthermore, our findings may help to explain one biological role of the human paranasal sinuses.