Respiratory and allergic health effects of dampness, mold, and dampness-related agents: a review of the epidemiologic evidence

Objectives

Many studies have shown consistent associations between evident indoor dampness or mold and respiratory or allergic health effects, but causal links remain unclear. Findings on measured microbiologic factors have received little review. We conducted an updated, comprehensive review on these topics.

Data sources

We reviewed eligible peer-reviewed epidemiologic studies or quantitative meta-analyses, up to late 2009, on dampness, mold, or other microbiologic agents and respiratory or allergic effects.

Data extraction

We evaluated evidence for causation or association between qualitative/subjective assessments of dampness or mold (considered together) and specific health outcomes. We separately considered evidence for associations between specific quantitative measurements of microbiologic factors and each health outcome.

Data synthesis

Evidence from epidemiologic studies and meta-analyses showed indoor dampness or mold to be associated consistently with increased asthma development and exacerbation, current and ever diagnosis of asthma, dyspnea, wheeze, cough, respiratory infections, bronchitis, allergic rhinitis, eczema, and upper respiratory tract symptoms. Associations were found in allergic and nonallergic individuals. Evidence strongly suggested causation of asthma exacerbation in children. Suggestive evidence was available for only a few specific measured microbiologic factors and was in part equivocal, suggesting both adverse and protective associations with health.

Conclusions

Evident dampness or mold had consistent positive associations with multiple allergic and respiratory effects. Measured microbiologic agents in dust had limited suggestive associations, including both positive and negative associations for some agents. Thus, prevention and remediation of indoor dampness and mold are likely to reduce health risks, but current evidence does not support measuring specific indoor microbiologic factors to guide health-protective actions.     

Serum IgG antibodies to mold spores in two norwegian sawmill populations: Relationship to respiratory and other work-related symptoms

Wood trimmers and planing operators from two separate sawmill populations (N = 303 and 170) were studied by serology assessment and a self-administered questionnaire. IgG antibodies to Rhizopus microsporus ssp. rhizopodiformis, Paecilomyces variotti, and Aspergillus fumigatus were measured by ELISA. The questionnaire included questions about general respiratory symptoms and symptoms after handling moldy timber. Personal exposure of wood trimmers to mold spores and wood dust was measured in one part of the sawmills. R. microsporus was the most prevalent mold assessed by serology. Antibody levels were higher and symptoms suggestive of mucous membrane irritation, chronic nonspecific lung disease, allergic alveolitis, and organic dust toxic syndrome were more frequently reported by wood trimmers than by planing operators. The mean level of IgG antibodies to R. microsporus in sawmill workers working in the same work area was the best predictor of symptoms in both populations. The consistent results indicate that exposure to spores of R. microsporus may cause several respiratory symptoms in wood trimmers. © 1993 Wiley-Liss, Inc.     

A comparison of health care use for physician-referred and self-referred episodes of outpatient physical therapy

Objective

To compare patient profiles and health care use for physician-referred and self-referred episodes of outpatient physical therapy (PT).

Data Source

Five years (2003–2007) of private health insurance claims data, from a Midwest insurer, on beneficiaries aged 18–64.

Study Design

Retrospective analyses of health care use of physician-referred (N = 45,210) and self-referred (N = 17,497) ambulatory PT episodes of care was conducted, adjusting for age, gender, diagnosis, case mix, and year.

Data Collection/Extraction

Physical therapy episodes began with the physical therapist initial evaluation and ended on the last date of service before 60 days of no further visits. Episodes were classified as physician-referred if the patient had a physician claim from a reasonable referral source in the 30 days before the start of PT.

Principal Findings

The self-referred group was slightly younger, but the two groups were very similar in regard to diagnosis and case mix. Self-referred episodes had fewer PT visits (86 percent of physician-referred) and lower allowable amounts ($0.87 for every $1.00), after covariate adjustment, but did not differ in related health care utilization after PT.

Conclusions

Health care use during PT episodes was lower for those who self-referred, after adjusting for key variables, but did not differ after the PT episode.     

Effects of cooking fuel smoke on respiratory symptoms and lung function in semi-rural women in Cameroon

Background:

Indoor air pollution is a major health problem in the developing world. In sub-Saharan Africa more than 90% of people rely on biomass to meet their domestic energy demands. Pollution from biomass fuel ranks 10th among preventable risk factors contributing to the global burden of diseases.

Objectives:

The present study aimed to determine the prevalence of respiratory symptoms and the factors associated with reduced lung function in a population of women exposed to cooking fuel smoke.

Methods:

A cross-sectional study was conducted in a semi-rural area in Cameroon. We compared forced respiratory volume between women using wood (n = 145) and women using alternative sources of energy (n = 155) for cooking.

Results:

Chronic bronchitis was found in 7·6% of the wood smoke group and 0·6% in the alternative fuels group. We observed two cases of airflow obstruction in the wood smoke group. Factors associated with lung function impairment were chronic bronchitis, use of wood as cooking fuel, age, and height.

Conclusion:

Respiratory symptoms and reduced lung function are more pronounced among women using wood as cooking fuel. Improved stoves technology should be developed to reduce the effects of wood smoke on respiratory health.     

A higher risk of congenital anomalies in the offspring of personnel who served aboard a Norwegian missile torpedo boat

Background

In the 1990s, congenital anomalies were reported among children whose fathers had served aboard a Norwegian missile torpedo boat (MTB). The Royal Norwegian Navy asked the University of Bergen to look into this problem as one part of a general health and work environment surveillance.

Aims

To estimate any increased risk of having children with congenital anomalies and having stillborn children among the offspring of workers that had served aboard the MTB and to investigate possible differences in exposure and other risk factors between these groups.

Methods

Data from a cross‐sectional study among all current employees of the Norwegian Navy (n = 2265, response rate 58%) were analysed.

Results

The prevalence ratio of having a child with congenital malformations associated with working on the ship was 4.0 (95% CI 1.9 to 8.6). The prevalence ratio of having a child who was stillborn or died within one week was 4.1 (95% CI 1.7 to 9.9).

Conclusion

Service aboard the MTB was associated with an increased risk of having children with congenital birth defects and having children that were stillborn. The causes of these findings are unknown.     

Risk of Asthmatic Episodes in Children Exposed to Sulfur Dioxide Stack Emissions from a Refinery Point Source in Montreal,Canada

Background

Little is known about the respiratory effects of short-term exposures to petroleum refinery emissions in young children. This study is an extension of an ecologic study that found an increased rate of hospitalizations for respiratory conditions among children living near petroleum refineries in Montreal (Canada).

Methods

We used a time-stratified case–crossover design to assess the risk of asthma episodes in relation to short-term variations in sulfur dioxide levels among children 2–4 years of age living within 0.5–7.5 km of the refinery stacks. Health data used to measure asthma episodes included emergency department (ED) visits and hospital admissions from 1996 to 2004. We estimated daily levels of SO₂ at the residence of children using a) two fixed-site SO₂ monitors located near the refineries and b) the AERMOD (American Meteorological Society/Environmental Protection Agency Regulatory Model) atmospheric dispersion model. We used conditional logistic regression to estimate odds ratios associated with an increase in the interquartile range of daily SO₂ mean and peak exposures (31.2 ppb for AERMOD peaks). We adjusted for temperature, relative humidity, and regional/urban background air pollutant levels.

Results

The risks of asthma ED visits and hospitalizations were more pronounced for same-day (lag 0) SO₂ peak levels than for mean levels on the same day, or for other lags: the adjusted odds ratios estimated for same-day SO₂ peak levels from AERMOD were 1.10 [95% confidence interval (CI), 1.00–1.22] and 1.42 (95% CI, 1.10–1.82), over the interquartile range, for ED visits and hospital admissions, respectively.

Conclusions

Short-term episodes of increased SO₂ exposures from refinery stack emissions were associated with a higher number of asthma episodes in nearby children.     

Effect of Hominis Placenta on cutaneous wound healing in normal and diabetic mice

BACKGROUND/OBJECTIVES

The number of diabetic patients has recently shown a rapid increase, and delayed wound healing is a major clinical complication in diabetes. In this study, the wound healing effect of Hominis placenta (HP) treatment was investigated in normal and streptozotocin-induced diabetic mice.

MATERIALS/METHODS

Four full thickness wounds were created using a 4 mm biopsy punch on the dorsum. HP was injected subcutaneously at the middle region of the upper and lower wounds. Wounds were digitally photographed and wound size was measured every other day until the 14th day. Wound closure rate was analyzed using CANVAS 7SE software. Wound tissues were collected on days 2, 6, and 14 after wounding for H/E, immunohistochemistry for FGF2, and Masson''s trichrome staining for collagen study.

RESULTS

Significantly faster wound closure rates were observed in the HP treated group than in normal and diabetes control mice on days 6 and 8. Treatment with HP resulted in reduced localization of inflammatory cells in wounded skin at day 6 in normal mice and at day 14 in diabetic mice (P < 0.01). Expression of fibroblast growth factor (FGF) 2 showed a significant increase in the HP treated group on day 14 in both normal (P < 0.01) and diabetic mice (P < 0.05). In addition, HP treated groups showed a thicker collagen layer than no treatment groups, which was remarkable on the last day, day 14, in both normal and diabetic mice.

CONCLUSIONS

Taken together, HP treatment has a beneficial effect on acceleration of cutaneous wound healing via regulation of the entire wound healing process, including inflammation, proliferation, and remodeling.     

Thermal-work strain in law enforcement personnel during chemical,biological, radiological,and nuclear (CBRN) training

Background:

Thermal safety standards for the use of chemical, biological, radiological, and nuclear (CBRN) ensembles have been established for various US occupations, but not for law enforcement personnel.

Objectives:

We examined thermal strain levels of 30 male US law enforcement personnel who participated in CBRN field training in Arizona, Florida, and Massachusetts.

Methods:

Physiological responses were examined using unobtrusive heart rate (HR) monitors and a simple thermoregulatory model to predict core temperature (T_c) using HR and environment.

Results:

Thermal strain levels varied by environments, activity levels, and type of CBRN ensemble. Arizona and Florida volunteers working in hot-dry and hot-humid environment indicated high heat strain (predicted max T_c>38.5°C). The cool environment of Massachusetts reduced thermal strain although thermal strains were occasionally moderate.

Conclusions:

The non-invasive method of using physiological monitoring and thermoregulatory modeling could improve law enforcement mission to reduce the risk of heat illness or injury.     

A cross sectional study of the respiratory health of workers handling printing toner dust

Background

Although recent case reports have suggested possible respiratory effects of solid toner dust inhalation, this hypothesis has not been verified by epidemiological studies.

Objectives

To conduct a cross sectional study to evaluate the association between the biological indices of lung fibrosis and toner dust exposure in an occupational cohort handling solid toner dust in their work life.

Methods

A total of 600 male toner workers and 212 control subjects were surveyed in terms of their subjective respiratory symptoms, pulmonary functions, and chest radiographic findings. In addition to the exposure history, the current working conditions and personal exposure levels to toner dust were also examined.

Results

Although subjects handling toner for more than 20 years tended to show a higher prevalence of respiratory symptoms and minimal chest x ray abnormalities, there was no consistent relation between the exposure to toner dust and the biological responses of the respiratory system.

Conclusion

Deterioration of respiratory health related to toner dust exposure is less likely to occur in current well controlled work environments, especially if the powdered toner is handled carefully. Nonetheless, it is important to collect further epidemiological evidence on the biological effects of toner dust inhalation, preferably using a longitudinal study design.     

The effects of quality improvement for depression in primary care at nine years: results from a randomized, controlled group-level trial

Objective

To examine 9-year outcomes of implementation of short-term quality improvement (QI) programs for depression in primary care.

Data Sources

Depressed primary care patients from six U.S. health care organizations.

Study Design

Group-level, randomized controlled trial.

Data Collection

Patients were randomly assigned to short-term QI programs supporting education and resources for medication management (QI-Meds) or access to evidence-based psychotherapy (QI-Therapy); and usual care (UC). Of 1,088 eligible patients, 805 (74 percent) completed 9-year follow-up; results were extrapolated to 1,269 initially enrolled and living. Outcomes were psychological well-being (Mental Health Inventory, five-item version [MHI5]), unmet need, services use, and intermediate outcomes.

Principal Findings

At 9 years, there were no overall intervention status effects on MHI5 or unmet need (largest F (2,41)=2.34, p=.11), but relative to UC, QI-Meds worsened MHI5, reduced effectiveness of coping and among whites lowered tangible social support (smallest t(42)=2.02, p=.05). The interventions reduced outpatient visits and increased perceived barriers to care among whites, but reduced attitudinal barriers due to racial discrimination and other factors among minorities (smallest F (2,41)=3.89, p=.03).

Conclusions

Main intervention effects were over but the results suggest some unintended negative consequences at 9 years particularly for the medication-resource intervention and shifts to greater perceived barriers among whites yet reduced attitudinal barriers among minorities.     

Short-Term Changes in Respiratory Biomarkers after Swimming in a Chlorinated Pool

Background

Swimming in chlorinated pools involves exposure to disinfection by-products (DBPs) and has been associated with impaired respiratory health.

Objectives

We evaluated short-term changes in several respiratory biomarkers to explore mechanisms of potential lung damage related to swimming pool exposure.

Methods

We measured lung function and biomarkers of airway inflammation [fractional exhaled nitric oxide (FeNO), eight cytokines, and vascular endothelial growth factor (VEGF) in exhaled breath condensate], oxidative stress (8-isoprostane in exhaled breath condensate), and lung permeability [surfactant protein D (SP-D) and the Clara cell secretory protein (CC16) in serum] in 48 healthy nonsmoking adults before and after they swam for 40 min in a chlorinated indoor swimming pool. We measured trihalomethanes in exhaled breath as a marker of individual exposure to DBPs. Energy expenditure during swimming, atopy, and CC16 genotype (rs3741240) were also determined.

Results

Median serum CC16 levels increased from 6.01 to 6.21 μg/L (average increase, 3.3%; paired Wilcoxon test p = 0.03), regardless of atopic status and CC16 genotype. This increase was explained both by energy expenditure and different markers of DBP exposure in multivariate models. FeNO was unchanged overall but tended to decrease among atopics. We found no significant changes in lung function, SP-D, 8-isoprostane, eight cytokines, or VEGF.

Conclusions

We detected a slight increase in serum CC16, a marker of lung epithelium permeability, in healthy adults after they swam in an indoor chlorinated pool. Exercise and DBP exposure explained this association, without involving inflammatory mechanisms. Further research is needed to confirm the results, establish the clinical relevance of short-term serum CC16 changes, and evaluate the long-term health impacts.     

Physical Activity,Gender Difference,and Depressive Symptoms

Objective

To investigate the roles of physical activity (exercise) and sociodemographic factors in depressive symptoms among men and women in the United States.

Data Source

2011 U.S. Behavioral Risk Factor Surveillance System (BRFSS).

Study Design

Patient Health Questionnaire Depression Scale (PHQ-8) scores are aggregated and divided into five categories. An ordered switching probability model with binary endogenous physical activity is developed to accommodate ordinality of depression categories and ameliorate statistical biases due to endogeneity of physical activity.

Principal Findings

Average treatment effects suggest physical activity ameliorates depressive symptoms among mildly and moderately depressed individuals, most notably among mildly depressed women. Gender differences exist in the roles of sociodemographic factors, with age, income, race, education, employment status, and recent mental health condition playing differentiated roles in affecting depressive symptoms.

Conclusions

Regular physical activity reduces depressive symptoms among both men and women with mild to moderate depression, notably among women.     

Occupational exposure to Aspergillus and aflatoxins among food-grain workers in India

Background:

Aflatoxins are a metabolite of Aspergillus molds and are widespread in the natural environment. Workers who handle food grains are at increased risk of exposure to aflatoxins and subsequently certain respiratory conditions. In India, more than half of the employed population is engaged in some type of agricultural work, yet little known about the respiratory problems as a result of exposure to aflatoxins among workers who handle food grains in India.

Objectives:

The aim of this study was to determine the risk of occupational exposure to aflatoxins in food-grain workers compared to workers who are not occupationally exposed to food grains.

Methods:

Bronchoalveolar lavage (BAL) and serum samples from 46 food-grain workers and 44 non-food-grain workers were analyzed for the presence of aflatoxins. Microscopy and culture of BAL samples were performed to detect Aspergillus species.

Results:

Aflatoxins were detected in 32.6% of the food-grain workers and 9.1% of non food grain workers (P<0.01). A significant difference was also found in BAL culture for Aspergillus (P<0.01) between the two groups. About 47.8% of the food-grain workers and 11.4% of non-food-grain workers had chronic respiratory symptoms.

Conclusion:

Occupational exposure to aflatoxins in food-grain workers was found to be associated with the increased presence of respiratory symptoms.     

The First Identification of Encephalitozoon cuniculi Infection in an Animal Care Worker in Turkey

Background:

As a zoonotic pathogen, Encephalitozoon cuniculi is a cause of serious disease in animals and people. The present study was to evaluate the health status examination of this seropositive animal care worker in our previous study.

Methods:

Blood samples were taken from five workers. CIA test was applied to detect antibodies against E. cuniculi in blood serum. The indirect immunofluorescence antibody test was used as confirmation test. Seropositive worker had a complete medical examination.

Results:

Only one worker was found to be seropositive according to the results of the serological test. Sera positive to E. cuniculi was confirmed with IFAT and spores were detected in the urine sample of the worker. The worker was treated with albendazole.

Conclusion:

Rabbits should be examined routinely for the presence of anti-E. cuniculi antibody. People working with laboratory animal should avoid contact with urine and faeces of infected or pay attention to personal hygiene.     

Impact of Environmental Chemicals on Lung Development

Background

Disruption of fundamental biologic processes and associated signaling events may result in clinically significant alterations in lung development.

Objectives

We reviewed evidence on the impact of environmental chemicals on lung development and key signaling events in lung morphogenesis, and the relevance of potential outcomes to public health and regulatory science.

Data sources

We evaluated the peer-reviewed literature on developmental lung biology and toxicology, mechanistic studies, and supporting epidemiology.

Data synthesis

Lung function in infancy predicts pulmonary function throughout life. In utero and early postnatal exposures influence both childhood and adult lung structure and function and may predispose individuals to chronic obstructive lung disease and other disorders. The nutritional and endogenous chemical environment affects development of the lung and can result in altered function in the adult. Studies now suggest that similar adverse impacts may occur in animals and humans after exposure to environmentally relevant doses of certain xenobiotics during critical windows in early life. Potential mechanisms include interference with highly conserved factors in developmental processes such as gene regulation, molecular signaling, and growth factors involved in branching morphogenesis and alveolarization.

Conclusions

Assessment of environmental chemical impacts on the lung requires studies that evaluate specific alterations in structure or function—end points not regularly assessed in standard toxicity tests. Identifying effects on important signaling events may inform protocols of developmental toxicology studies. Such knowledge may enable policies promoting true primary prevention of lung diseases. Evidence of relevant signaling disruption in the absence of adequate developmental toxicology data should influence the size of the uncertainty factors used in risk assessments.     

Pre-treatment loss to follow-up among smear-positive pulmonary tuberculosis cases: a 10-year audit of national data from Fiji

Setting:

All tuberculosis (TB) diagnostic and treatment centres in Fiji.

Objectives:

To report on pre-treatment loss to follow-up rates over a 10-year period (2001–2010) and to examine if patients’ age, sex and geographic origin are associated with the observed shortcomings in the health services.

Methods:

A retrospective review of routine programme data reconciling TB laboratory and treatment registers.

Results:

A total of 690 sputum smear-positive TB patients were diagnosed in the laboratory, of whom 579 (84%) were started on anti-tuberculosis treatment—an overall pre-treatment loss to follow-up of 111 (16%). Peak loss to follow-up rates were seen in 2003, 2004 and 2010. Pre-treatment losses were all aged ≥15 years. In the Western Division of Fiji, 33% of sputum-positive patients were declared pre-treatment loss to follow-up; this division had over five times the risk of such an adverse outcome compared to the Central Division (OR 5.2, 95%CI 3.1–8.9, P < 0.0001).

Conclusion:

This study has identified an important shortcoming in programme linkage, communication and feedback between TB diagnostic and treatment services, leading to high pre-treatment loss to follow-up rates. This negatively influences TB services, and ways to rectify this situation are discussed.     

Trawler fuel exhaust and respiratory impairments: a cross-sectional pilot study among Indian fishermen working in informal sectors

Background:

An estimated half a billion people are engaged in fishing related occupations in India. Exposure to adulterated fuel exhaust is common among deep-sea fishermen, yet little is known about the potential impacts on the exposure to health.

Objective:

The aim of this study was to investigate whether fuel emission exposure was associated with increased respiratory impairments among fishermen who were occupationally exposed to fuel exhaust compared to fisherman occupationally unexposed to fuel exhaust.

Methods:

This cross-sectional study compared the prevalence of respiratory symptoms and lung function variables between 152 marine-water and 107 fresh water fishermen considering the use of fuel-driven trawlers. Data were obtained from questionnaires and computerized spirometer.

Results:

Fishermen exposed to trawler fuel exhaust reported more than double the number of respiratory symptoms compared to the unexposed fisherman (86.2 vs. 40.2%). They also had a significantly higher chance experiencing chronic cough (adjusted OR = 3.51, 95% confidence interval (CI) = 2.09–6.35), chronic phlegm (8.61, 4.76–15.97), and wheezing (4.29, 2.55–7.61) symptoms. Finally, there was a significant reduction of the ratio of mid portion of forced expiratory flow rate and forced vital capacity (FEF_25–75/FVC) in the exposed fishermen compared to the unexposed (0.84 vs. 0.73 second⁻¹, P = 0.015).

Conclusion:

Fuel exhaust may negatively impact on the respiratory health of Indian fishermen. More attention and surveillance of occupational health for fishermen in India is needed.     

Epidemiological Investigation of an Outbreak of Salmonellosis in Gyeongju,Korea

Objectives

A salmonellosis outbreak occurred within a community of Gyeongju residents who ingested catered food from a wedding in June 2009. We aimed to epidemiologically investigate the probable vehicle of the infection.

Methods

We conducted a retrospective cohort study on 34 local residents who ingested the wedding food.

Results

Among the 34 residents, 31 (91.2%) reported symptoms of infection after eating the food. Among all of the wedding foods, pan-fried foods were highly associated with the diarrheal attack rate. On bacteriological examination, Salmonella species were detected in the pan-fried foods among the leftover foods and in 17 of the 31 stool specimens from the cases. There were five different types of pan-fried foods, but the onset of symptoms was independent of the ingredients used. We found that the pan-fried food was prepared at a food store in Seoul and that eggs were a common ingredient.

Conclusions

The major cause of the salmonellosis in this population was presumed to be the pan-fried food prepared with contaminated eggs. These food items might have been partially undercooked because of their irregular shape, which allowed the Salmonella species to survive and multiply before ingestion.     

Mental Health and High‐Cost Health Care Utilization: New Evidence from Axis II Disorders

Objective

To analyze the associations between Axis II (A2) disorders and two measures of health care utilization with relatively high cost: emergency department (ED) episodes and hospital admissions.

Data Source/Study Setting

Wave I (2001/2002) and Wave II (2004/2005) of the National Longitudinal Survey on Alcohol and Related Conditions (NESARC).

Study Design

A national probability sample of adults. Gender-stratified regression analysis adjusted for a range of covariates associated with health care utilization.

Data Collection

The target population of the NESARC is the civilian noninstitutionalized population aged 18 years and older residing in the United States. The cumulative survey response rate is 70.2 percent with a response rate of 81 percent (N = 43,093) in Wave I and 86.7 percent (N = 34,653) in Wave II.

Principal Findings

Both men and women with A2 disorders are at elevated risk for ED episodes and hospital admissions. Associations are robust after adjusting for a rich set of confounding factors, including Axis I (clinical) psychiatric disorders. We find evidence of a dose–response relationship, while antisocial and borderline disorders exhibit the strongest associations with both measures of health care utilization.

Conclusions

This study provides the first published estimates of the associations between A2 disorders and high-cost health care utilization in a large, nationally representative survey. The findings underscore the potential implications of these disorders on health care expenditures.