Audiometric notch and extended high-frequency hearing threshold shift in relation to total leisure noise exposure: An exploratory analysis.

BACKGROUND: Studies investigating leisure noise effect on extended high frequency hearing are insufficient and they have inconsistent results. The aim of this study was to investigate if extended high-frequency hearing threshold shift is related to audiometric notch, and if total leisure noise exposure is associated with extended high-frequency hearing threshold shift. MATERIALS AND METHODS: A questionnaire of the Ohrkan cohort study was used to collect information on demographics and leisure time activities. Conventional and extended high-frequency audiometry was performed. We did logistic regression between extended high-frequency hearing threshold shift and audiometric notch as well as between total leisure noise exposure and extended high-frequency hearing threshold shift. Potential confounders (sex, school type, and firecrackers) were included. RESULTS: Data from 278 participants (aged 18-23 years, 53.2% female) were analyzed. Associations between hearing threshold shift at 10, 11.2, 12.5, and 14 kHz with audiometric notch were observed with a higher prevalence of threshold shift at the four frequencies, compared to the notch. However, we found no associations between total leisure noise exposure and hearing threshold shift at any extended high frequency. CONCLUSION: This exploratory analysis suggests that while extended high-frequency hearing threshold shifts are not related to total leisure noise exposure, they are strongly associated with audiometric notch. This leads us to further explore the hypothesis that extended high-frequency threshold shift might be indicative of the appearance of audiometric notch at a later time point, which can be investigated in the future follow-ups of the Ohrkan cohort.

[Environmental health relevance of airborne microorganisms in ambient and indoor air]. / Umweltmedizinische Relevanz von luftgetragenen Mikroorganismen im Außen- und Innenbereich.

Airborne microorganisms occur ubiquitously in the ambient air. Besides allergic and irritative-toxic effects, they can cause infections after inhalation. Occupational studies have shown that an increased incidence of respiratory diseases is found in adequately exposed workers. In addition to respiratory diseases, severe systemic infections can also occur in particular cases, such as in the case of a hantavirus infection that is recognized as an occupational disease. In studies from environmental medicine, respiratory diseases have also been observed in residents living in the vicinity of livestock facilities and evaporative cooling towers. In the latter case, an infection risk may be caused by inhalation of legionella-contaminated aerosol from the exhaust air of such systems.Currently, there are no health-related exposure limits for airborne microorganisms released from such facilities. Environmental risk assessment can be carried out on the basis of the guideline VDI 4250 part 1, which relies on an excess of natural background concentration by facility-specific emissions. For the approval practice, the LAI-Leitfaden Bioaerosole is a uniform, standardized method for the determination and assessment of bioaerosol exposure.In indoor spaces, only a few mold types, such as Aspergillus fumigatus are able to trigger infections by local or systemic infection of the human organism. In particular, persons with an immune deficiency or allergies must be informed about the risks of mold exposure in indoor air. In general, mold growth in indoor spaces is a hygienic problem and must not be accepted as a matter of principle.

AWMF mold guideline "Medical clinical diagnostics for indoor mold exposure" - Update 2023 AWMF Register No. 161/001.

None.

The Relevance of Leisure Noise to Hearing Threshold Shifts: A Longitudinal Analysis Among Adolescents.

PURPOSE: The aim of this study was to analyze the association of total leisure noise exposure and hearing threshold shifts over 5 years among adolescents enrolled in the Ohrkan cohort study. METHOD: The Ohrkan cohort of 2,148 students aged 13-19 years was recruited from 2009 to 2011 and followed up 5 years later. Complete baseline and follow-up reports on exposure and outcome were available for 989 participants. Leisure noise exposure was assessed by questionnaires, and clinical audiometric examinations were performed. Two outcomes were defined: occurrence of the Niskar notch pattern and audiometry showing maximum hearing threshold values at 3, 4, and 6 kHz (both ears). Longitudinal analysis using generalized estimating equations was performed. RESULTS: High total leisure noise exposure, defined as an energy equivalent of a 40-hr week of > 85 dBA, was estimated for 32.7% of students at baseline and 63.8% at follow-up. A noise notch was observed in 1.1% of adolescents at baseline and 3.3% at follow-up. At baseline, the maximum measured threshold shift was 55 dB, which increased to 85 dB at the follow-up. Longitudinal analysis did not reveal an association between leisure noise exposure and hearing thresholds. Hearing threshold shifts or noise notches were associated with sex, school type, and time point of measurement. CONCLUSIONS: No relationship was found between leisure noise and hearing thresholds. Male adolescents and those attending secondary general schools, with graduation following completion of ninth or 10th grade, had a greater likelihood of developing hearing threshold shifts. Prevention programs should focus on these risk groups. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.19233462.

Exposure to air pollution in critical prenatal time windows and IgE levels in newborns.

The objective of this study was to analyze the mechanisms by which exposure to ambient air pollutants influences respiratory health may include altered prenatal immune development. To analyze associations between elevated cord serum Immunoglobulin E (IgE) levels and maternal air pollution exposure during each month of gestation. Total cord serum IgE was determined by the CAP system and mothers' total IgE levels by nephelometry for 459 births in the Czech Republic from May 1994 to mid-January 1997. Concentrations of polycyclic aromatic hydrocarbons (PAHs) and particulate matter <2.5 microns in diameter (PM(2.5) ) were measured in ambient air, and arithmetic means were calculated for each gestational month. Log binomial regression models were used to estimate prevalence ratios (PR) for elevated cord serum IgE (≥0.9 IU/ml) adjusting for district of residence, year of birth, and in further models, for maternal IgE (a surrogate for atopy) and gestational season. Heterogeneity by maternal atopy status was evaluated for associations of air pollution and of cigarette smoke. In adjusted models, PAH and PM(2.5) exposures in the second month of gestation were each associated with a lower prevalence of elevated cord serum IgE. For an average increase of 100 ng/m(3) of PAHs, the PR was 0.69 (95% confidence interval (CI): 0.50, 0.95); for 25 µg/m(3) increase in PM(2.5) , the PR was 0.77 (95% CI: 0.55, 1.07). Conversely, exposures later in gestation were associated with a higher prevalence of elevated cord IgE: in the fifth month, the PR for PAH exposure was 1.64 (95% CI: 1.29, 2.08), while for PM(2.5) in the sixth month, it was 1.66 (95% CI: 1.30, 2.13). In analyses stratified by maternal atopy, air pollutants were associated with altered cord serum IgE only among neonates with non-atopic mothers. Similarly, an association of cigarette smoke with elevated cord serum IgE was found only in non-atopic mothers. PAHs and PM(2.5) , constituents of both ambient air pollution and cigarette smoke, appear to influence fetal immune development, particularly among infants whose mothers are not atopic.

Air pollution exposure during critical time periods in gestation and alterations in cord blood lymphocyte distribution: a cohort of livebirths.

BACKGROUND: Toxic exposures have been shown to influence maturation of the immune system during gestation. This study investigates the association between cord blood lymphocyte proportions and maternal exposure to air pollution during each gestational month. METHODS: Cord blood was analyzed using a FACSort flow cytometer to determine proportions of T lymphocytes (CD3+ cells and their subsets, CD4+ and CD8+), B lymphocytes (CD19+) and natural killer (NK) cells. Ambient air concentrations of 12 polycyclic aromatic hydrocarbons (PAH) and particulate matter < 2.5 micrometer in diameter (PM2.5) were measured using fixed site monitors. Arithmetic means of these pollutants, calculated for each gestational month, were used as exposure metrics. Data on covariates were obtained from medical records and questionnaires. Multivariable linear regression models were fitted to estimate associations between monthly PAH or PM2.5 and cord blood lymphocytes, adjusting for year of birth and district of residence and, in further models, gestational season and number of prior live births. RESULTS: The adjusted models show significant associations between PAHs or PM2.5 during early gestation and increases in CD3+ and CD4+ lymphocytes percentages and decreases in CD19+ and NK cell percentages in cord blood. In contrast, exposures during late gestation were associated with decreases in CD3+ and CD4+ fractions and increases in CD19+ and NK cell fractions. There was no significant association between alterations in lymphocyte distribution and air pollution exposure during the mid gestation. CONCLUSIONS: PAHs and PM2.5 in ambient air may influence fetal immune development via shifts in cord blood lymphocytes distributions. Associations appear to differ by exposure in early versus late gestation.

Assessment of somatic complaints in environmental health.

In patients attributing their health complaints to environmental factors (EnvPat) evidence based medical diagnostics usually do not confirm environmental and somatic causes of symptoms. Many symptoms remain unexplained. Aim of the study was the systematic assessment of medically unexplained physical symptoms (MUPS) in EnvPat and comparison to symptom rates reported by subjects of an environmental study exposed to environmental odors (EnvExp). This specific exposure was chosen, as odors are associated by an unclear mechanism with physical symptoms. By this we aimed to enlighten the open question as to likeliness that MUPS of EnvPat are caused by hitherto unrevealed environmental exposures or result from somatization. MUPS were measured with SOMS-2 in EnvPat n=92, patients presenting in a university environmental outpatients clinic, and different study groups exposed to environmental odors (EnvExp). These were: (1) subjects exposed to annoying odors and medically relevant concentrations of bioaerosols, such as airborne microorganisms (EnvExp-1, n=74), and (2) subjects exposed to odors alone (EnvExp-2, n=282) as well as unexposed controls (Controls, n=235). Logistic regression and analysis of variance were applied to analyze rates of single complaints and the sum index of complaints (SOMS-CoIx). In EnvPat rates of MUPS were highest - significant (p<0.05) adjusted OR in 23 of 25 MUPS compared to controls - and highest SOMS-CoIx (mean 15.3 (S.D. +/-9.3). Rates of MUPS were lower in environmentally exposed subjects with difference in the two strata: while EnvExp-1 differed in several complaints, i.e., nausea and SOMS-CoIx (mean 7.2, S.D. +/-6.9) from controls (p<0.05), EnvExp-2 (SOMS-CoIx mean 4.8, S.D. +/-5.2) showed relevant differences only in two single complaints and not in the SOMS-CoIx from controls, SOMS-CoIx mean 3.9, S.D. +/-5.0. This remained when adjusting for age, gender, and school education. Rates of MUPS in environmental patients were clearly higher than in subjects with actual environmental exposure, making it unlikely that their symptoms are due to undetected environmental factors. MUPS of EnvPat show similarities to psychosomatic patients. In the environmental survey symptom assessment by SOMS-2 was sensitive to different environmental scenarios, i.e., higher rates of physical complaints were only found in subjects with hazardous residential bioaerosols pollution as well as an annoying odor exposure and interestingly not in subjects exposed to annoying odors alone. This underlines that questionnaire data of somatic complaints need to be interpreted on the basis of exposure assessment in order to unjustly attribute health complaints to annoyance.

A systematic review of experimental animal studies on microbial bioaerosols: Dose-response data for the derivation of exposure limits.

Although exposure to high levels of microbial bioaerosols can be linked to the deterioration of the human respiratory system, precise exposure levels responsible for such effects are still unknown. A previous systematic review concluded that there was not enough information in the studies in humans to derive an exposure-response relationship. Thus, the aim of this systematic review was to derive exposure limits for microbial bioaerosols based on health effects in experimental animal studies. A systematic search was done in MEDLINE (PubMed) for long-term in vivo exposure of the respiratory system via inhalation of a quantified microbial bioaerosol. A total of n = 301 studies were retrieved. Abstract screening using predefined inclusion and exclusion criteria was followed by full-text screening and standardized data extraction of study characteristics and measured outcomes. As a result, four suitable studies were identified where mice or guinea pigs were exposed for 4-12 weeks to a previously described mixture of fungal spores or conidia via inhalation. The number of macrophages, neutrophils, eosinophils and lymphocytes following subchronic exposure has been reported by all included papers and suggested a dose- and time-dependent relationship. Significant inflammation was observed following subacute exposure to Aspergillus fumigatus. However, the outcomes of the studies could not be directly compared due to the large degree of variation and poor description of the exposure conditions. It is our conclusion that more experimental research needs to be done with the specific aim of establishing a No-Observed-Adverse-Effect Level (NOAEL) and a Lowest-Observed-Adverse-Effect Level (LOAEL) for exposure to microbial bioaerosols in ambient air. Expertise of both exposure and outcome assessment should be brought together to enable standardization of experimental animal studies with properly generated aerosols aiming to derive health-based exposure limits.

Building an automatic pollen monitoring network (ePIN): Selection of optimal sites by clustering pollen stations.

Airborne pollen is a recognized biological indicator and its monitoring has multiple uses such as providing a tool for allergy diagnosis and prevention. There is a knowledge gap related to the distribution of pollen traps needed to achieve representative biomonitoring in a region. The aim of this manuscript is to suggest a method for setting up a pollen network (monitoring method, monitoring conditions, number and location of samplers etc.). As a case study, we describe the distribution of pollen across Bavaria and the design of the Bavarian pollen monitoring network (ePIN), the first operational automatic pollen network worldwide. We established and ran a dense pollen monitoring network of 27 manual Hirst-type pollen traps across Bavaria, Germany, during 2015. Hierarchical cluster analysis of the data was then performed to select the locations for the sites of the final pollen monitoring network. According to our method, Bavaria can be clustered into three large pollen regions with eight zones. Within each zone, pollen diversity and distribution among different locations does not vary significantly. Based on the pollen zones, we opted to place one automatic monitoring station per zone resulting in the ePIN network, serving 13 million inhabitants. The described method defines stations representative for a homogeneous aeropalynologically region, which reduces redundancy within the network and subsequent costs (in the study case from 27 to 8 locations). Following this method, resources in pollen monitoring networks can be optimized and allergic citizens can then be informed in a timely and effective way, even in larger geographical areas.

Assessment of environmental worry in health-related settings: Re-evaluation and modification of an environmental worry scale.

The aim of this article was to re-evaluate and possibly modify the standardized Environmental Worry Scale (EWS) by Hodapp et al. [1996. Evaluation eines Fragebogens zur Erfassung von Umweltbesorgnis. Z. Gesundheitspsychologie IV(1), 22-36] with regard to its content and structure. In order to do this, 161 participants were chosen as a reference group to take part in a survey. The data were analyzed and a factor analysis yielded two instead of one component of worry, namely "personal" and "general" environmental worry, leading to a new evaluation method. This revised evaluation method was then applied to patients (n=227) with or without self-reported multiple chemical sensitivity (MCS) and thus used in the context of reported health complaints. The outlined results indicate that the assessment of worry as proposed by Hodapp et al. [1996. Evaluation eines Fragebogens zur Erfassung von Umweltbesorgnis. Z. Gesundheitspsychologie IV(1), 22-36] should be elaborated by the newly developed evaluation method with which a ratio determined by "personal" and "general" worry can be calculated. In addition to analyzing the absolute quantity of worry, the calculated ratio allows to draw conclusions on the structure of worry. It will be discussed to what extent the results present new insights into the role of worry among patients suffering from environmental diseases.

Early childhood lower respiratory illness and air pollution.

BACKGROUND: Few studies of air pollutants address morbidity in preschool children. In this study we evaluated bronchitis in children from two Czech districts: Teplice, with high ambient air pollution, and Prachatice, characterized by lower exposures. OBJECTIVES: Our goal was to examine rates of lower respiratory illnesses in preschool children in relation to ambient particles and hydrocarbons. METHODS: Air monitoring for particulate matter < 2.5 microm in diameter (PM(2.5)) and polycyclic aromatic hydrocarbons (PAHs) was conducted daily, every third day, or every sixth day. Children born May 1994 through December 1998 were followed to 3 or 4.5 years of age to ascertain illness diagnoses. Mothers completed questionnaires at birth and at follow-up regarding demographic, lifestyle, reproductive, and home environmental factors. Longitudinal multivariate repeated-measures analysis was used to quantify rate ratios for bronchitis and for total lower respiratory illnesses in 1,133 children. RESULTS: After adjustment for season, temperature, and other covariates, bronchitis rates increased with rising pollutant concentrations. Below 2 years of age, increments in 30-day averages of 100 ng/m(3) PAHs and of 25 microg/m(3) PM(2.5) resulted in rate ratios (RRs) for bronchitis of 1.29 [95 % confidence interval (CI), 1.07-1.54] and 1.30 (95% CI, 1.08-1.58), respectively; from 2 to 4.5 years of age, these RRs were 1.56 (95% CI, 1.22-2.00) and 1.23 (95% CI, 0.94-1.62), respectively. CONCLUSION: Ambient PAHs and fine particles were associated with early-life susceptibility to bronchitis. Associations were stronger for longer pollutant-averaging periods and, among children > 2 years of age, for PAHs compared with fine particles. Preschool-age children may be particularly vulnerable to air pollution-induced illnesses.

The DNA repair gene XPD/ERCC2 polymorphisms Arg156Arg (exon 6) and Lys751Gln (exon 23) are closely associated.

In the context of a molecular epidemiology study dealing with the effects of individual genetic susceptibility on childhood respiratory morbidity, DNA repair genotypes for the XPD/ERCC2 gene in exon 6 (Arg156Arg) and exon 23 (Lys751Gln) have been analyzed by PCR/RFLP assays in DNA samples isolated from the fetal parts of placentas. The study was performed using a cohort of 729 children born in 1994-1998 in two districts of the Czech Republic. On the basis of these data, we tested the association between the two genotypes. The principal finding of this study is that the exon 6 and exon 23 polymorphisms in the XPD/ERCC2 gene are tightly associated, with persons who are homozygous CC in exon 23 being mostly (81%) homozygous CC in exon 6, and persons homozygous AA in exon 6 mostly (88%) homozygous AA in exon 23. This strong association may have serious consequences for the interpretation of cancer susceptibility and other molecular epidemiology studies dealing with the XPD6 and XPD23 genotypes, since the observed effects of the silent XPD6 polymorphism might be, in fact, the result of XPD23 polymorphism, which is connected with an amino acid substitution in the resulting XPD protein.

Detection of Legionella-contaminated aerosols in the vicinity of a bio-trickling filter of a breeding sow facility - A pilot study.

The urbanization of agricultural areas results in a reduction of distances between residential buildings and livestock farms. In the public debate, livestock farming is increasingly criticized due to environmental disturbance and odor nuisance originating from such facilities. One method to reduce odor and ammonia is by exhaust air treatment, for example, by biological exhaust air purification processes with bio-trickling filters filled with tap water. Higher temperatures in the summer time and the generation of biofilms are ideal growth conditions for Legionella. However, there are no studies on the presence of Legionella in the water of bio-trickling filters and the release of Legionella-containing aerosols. Therefore, the aim of this study was to investigate Legionella in wash water and emitted bioaerosols of a bio-trickling filter system of a breeding sow facility. For this purpose, measurements were carried out using a cyclone sampler. In addition, samples of wash water were taken. Legionella were not found by culture methods. However, using molecular biological methods, Legionella spp. could be detected in wash water as well as in bioaerosol samples. With antibody-based methods, Legionella pneumophila were identified. Further studies are needed to investigate the environmental health relevance of Legionella-containing aerosols emitted by such exhaust air purification systems.

Medical diagnostics for indoor mold exposure.

In April 2016, the German Society of Hygiene, Environmental Medicine and Preventative Medicine (Gesellschaft für Hygiene, Umweltmedizin und Präventivmedizin (GHUP)) together with other scientific medical societies, German and Austrian medical societies, physician unions and experts has provided an AWMF (Association of the Scientific Medical Societies) guideline 'Medical diagnostics for indoor mold exposure'. This guideline shall help physicians to advise and treat patients exposed indoors to mold. Indoor mold growth is a potential health risk, even without a quantitative and/or causal association between the occurrence of individual mold species and health effects. Apart from the allergic bronchopulmonary aspergillosis (ABPA) and the mycoses caused by mold, there is only sufficient evidence for the following associations between moisture/mold damages and different health effects: Allergic respiratory diseases, asthma (manifestation, progression, exacerbation), allergic rhinitis, exogenous allergic alveolitis and respiratory tract infections/bronchitis. In comparison to other environmental allergens, the sensitizing potential of molds is estimated to be low. Recent studies show a prevalence of sensitization of 3-10% in the total population of Europe. The evidence for associations to mucous membrane irritation and atopic eczema (manifestation, progression, exacerbation) is classified as limited or suspected. Inadequate or insufficient evidence for an association is given for COPD, acute idiopathic pulmonary hemorrhage in children, rheumatism/arthritis, sarcoidosis, and cancer. The risk of infections from indoor molds is low for healthy individuals. Only molds that are capable to form toxins can cause intoxications. The environmental and growth conditions and especially the substrate determine whether toxin formation occurs, but indoor air concentrations are always very low. In the case of indoor moisture/mold damages, everyone can be affected by odor effects and/or impairment of well-being. Predisposing factors for odor effects can be given by genetic and hormonal influences, imprinting, context and adaptation effects. Predisposing factors for impairment of well-being are environmental concerns, anxieties, conditioning and attributions as well as a variety of diseases. Risk groups that must be protected are patients with immunosuppression and with mucoviscidosis (cystic fibrosis) with regard to infections and individuals with mucoviscidosis and asthma with regard to allergies. If an association between mold exposure and health effects is suspected, the medical diagnosis includes medical history, physical examination, conventional allergy diagnosis, and if indicated, provocation tests. For the treatment of mold infections, it is referred to the AWMF guidelines for diagnosis and treatment of invasive Aspergillus infections. Regarding mycotoxins, there are currently no validated test methods that could be used in clinical diagnostics. From the perspective of preventive medicine, it is important that mold damages cannot be tolerated in indoor environments.

Abridged version of the AWMF guideline for the medical clinical diagnostics of indoor mould exposure: S2K Guideline of the German Society of Hygiene, Environmental Medicine and Preventive Medicine (GHUP) in collaboration with the German Association of Allergists (AeDA), the German Society of Dermatology (DDG), the German Society for Allergology and Clinical Immunology (DGAKI), the German Society for Occupational and Environmental Medicine (DGAUM), the German Society for Hospital Hygiene (DGKH), the German Society for Pneumology and Respiratory Medicine (DGP), the German Mycological Society (DMykG), the Society for Pediatric Allergology and Environmental Medicine (GPA), the German Federal Association of Pediatric Pneumology (BAPP), and the Austrian Society for Medical Mycology (ÖGMM).

This article is an abridged version of the AWMF mould guideline "Medical clinical diagnostics of indoor mould exposure" presented in April 2016 by the German Society of Hygiene, Environmental Medicine and Preventive Medicine (Gesellschaft für Hygiene, Umweltmedizin und Präventivmedizin, GHUP), in collaboration with the above-mentioned scientific medical societies, German and Austrian societies, medical associations and experts. Indoor mould growth is a potential health risk, even if a quantitative and/or causal relationship between the occurrence of individual mould species and health problems has yet to be established. Apart from allergic bronchopulmonary aspergillosis (ABPA) and mould-caused mycoses, only sufficient evidence for an association between moisture/mould damage and the following health effects has been established: allergic respiratory disease, asthma (manifestation, progression and exacerbation), allergic rhinitis, hypersensitivity pneumonitis (extrinsic allergic alveolitis), and increased likelihood of respiratory infections/bronchitis. In this context the sensitizing potential of moulds is obviously low compared to other environmental allergens. Recent studies show a comparatively low sensitizing prevalence of 3-10% in the general population across Europe. Limited or suspected evidence for an association exist with respect to mucous membrane irritation and atopic eczema (manifestation, progression and exacerbation). Inadequate or insufficient evidence for an association exist for chronic obstructive pulmonary disease, acute idiopathic pulmonary hemorrhage in children, rheumatism/arthritis, sarcoidosis and cancer. The risk of infection posed by moulds regularly occurring indoors is low for healthy persons; most species are in risk group 1 and a few in risk group 2 (Aspergillus fumigatus, A. flavus) of the German Biological Agents Act (Biostoffverordnung). Only moulds that are potentially able to form toxins can be triggers of toxic reactions. Whether or not toxin formation occurs in individual cases is determined by environmental and growth conditions, above all the substrate. In the case of indoor moisture/mould damage, everyone can be affected by odour effects and/or mood disorders. However, this is not a health hazard. Predisposing factors for odour effects can include genetic and hormonal influences, imprinting, context and adaptation effects. Predisposing factors for mood disorders may include environmental concerns, anxiety, condition, and attribution, as well as various diseases. Risk groups to be protected particularly with regard to an infection risk are persons on immunosuppression according to the classification of the German Commission for Hospital Hygiene and Infection Prevention (Kommission für Krankenhaushygiene und Infektionsprävention, KRINKO) at the Robert Koch- Institute (RKI) and persons with cystic fibrosis (mucoviscidosis); with regard to an allergic risk, persons with cystic fibrosis (mucoviscidosis) and patients with bronchial asthma should be protected. The rational diagnostics include the medical history, physical examination, and conventional allergy diagnostics including provocation tests if necessary; sometimes cellular test systems are indicated. In the case of mould infections the reader is referred to the AWMF guideline "Diagnosis and Therapy of Invasive Aspergillus Infections". With regard to mycotoxins, there are currently no useful and validated test procedures for clinical diagnostics. From a preventive medicine standpoint it is important that indoor mould infestation in relevant dimension cannot be tolerated for precautionary reasons. With regard to evaluating the extent of damage and selecting a remedial procedure, the reader is referred to the revised version of the mould guideline issued by the German Federal Environment Agency (Umweltbundesamt, UBA).

Air pollution and lymphocyte phenotype proportions in cord blood.

Effects of air pollution on morbidity and mortality may be mediated by alterations in immune competence. In this study we examined short-term associations of air pollution exposures with lymphocyte immunophenotypes in cord blood among 1,397 deliveries in two districts of the Czech Republic. We measured fine particulate matter < 2.5 microm in diameter (PM2.5) and 12 polycyclic aromatic hydrocarbons (PAHs) in 24-hr samples collected by versatile air pollution samplers. Cord blood samples were analyzed using a FACSort flow cytometer to determine phenotypes of CD3+ T-lymphocytes and their subsets CD4+ and CD8+, CD19+ B-lymphocytes, and natural killer cells. The mothers were interviewed regarding sociodemographic and lifestyle factors, and medical records were abstracted for obstetric, labor and delivery characteristics. During the period 1994 to 1998, the mean daily ambient concentration of PM2.5 was 24.8 microg/m3 and that of PAHs was 63.5 ng/m3. In multiple linear regression models adjusted for temperature, season, and other covariates, average PAH or PM2.5 levels during the 14 days before birth were associated with decreases in T-lymphocyte phenotype fractions (i.e., CD3+ CD4+, and CD8+), and a clear increase in the B-lymphocyte (CD19+) fraction. For a 100-ng/m3 increase in PAHs, which represented approximately two standard deviations, the percentage decrease was -3.3% [95% confidence interval (CI), -5.6 to -1.0%] for CD3+, -3.1% (95% CI, -4.9 to -1.3%) for CD4+, and -1.0% (95% CI, -1.8 to -0.2%) for CD8+ cells. The corresponding increase in the CD19+ cell proportion was 1.7% (95% CI, 0.4 to 3.0%). Associations were similar but slightly weaker for PM2.5. Ambient air pollution may influence the relative distribution of lymphocyte immunophenotypes of the fetus.

Evaluation of exposure-response relationships for health effects of microbial bioaerosols - A systematic review.

Studies suggest adverse health effects following exposure to bioaerosols in the environment and in particular at workplaces. However, there is still a lack of health-related exposure limits based on toxicological or epidemiological studies from environmental health or from the working environment. The aim of this study was to derive health-based exposure limits for bioaerosols that can protect the general population as group "at risk" via environmental exposure using analysis of peer-reviewed studies related to occupational medicine, indoor air and environmental health. The derivation of exposure limits should be conducted by the members of a bioaerosol expert panel according to established toxicological criteria. A systematic review was performed in Medline (PubMed) including studies containing both data on exposure measurements and observed health outcomes. In addition, literature recommended by the experts was considered. A comprehensive search strategy was generated and resulted in a total of n=1569 studies in combination with the literature recommendations. Subsequently, abstracts were screened using defined exclusion criteria yielding a final number of n=44 studies. A standardized extraction sheet was used to combine data on health effects and exposure to different bioaerosols. After full-text screening and extraction according to the defined exclusion criteria n=20 studies were selected all related to occupational exposures comprising the working areas wood processing, farming, waste processing and others. These studies were analyzed in collaboration with the bioaerosol expert network in terms of suitability for derivation of health-related exposure limits. The bioaerosol expert network concluded that none of the analyzed studies provided suitable dose-response relationships for derivation of exposure limits. The main reasons were: (1) lack of studies with valid dose-response data; (2) diversity of employed measuring methods for microorganisms and bioaerosol-emitting facilities; (3) heterogeneity of health effects; (4) insufficient exposure assessment. However, several indicator parameters and exposure concentrations could be identified for different bioaerosol-emitting facilities. Nevertheless, health-related exposure limits are urgently needed especially in approval procedures of facilities like composting plants or livestock farms emitting bioaerosols in the neighbourhood of residents. In the regulatory toxicology framework, it is common to use animal experimental studies for derivation of general exposure limits if appropriate environmental epidemiological studies on harmful substances are lacking. This might be another possibility to obtain health-related exposure limits for specific bioaerosol parameters. Furthermore, we recommend to use suitable measurable outcome parameters related to bioaerosols; to measure bioaerosols according to a protocol representative for exposure pattern and duration at the particular work place; to develop standardized detection methods for indicator parameters; to combine different detection methods to compensate for the limitations of each method; to apply new analysis methods to identify the real risk potential.

Ranking and frequency of somatic symptoms in residents near composting sites with odor annoyance.

The presented study reports the prevalence of somatic symptoms in three study samples living in the vicinity of composting plants. Microorganisms were measured in the air of the residential areas closest to the plants at the same time an epidemiological investigation was performed in the neighborhood near (150 to 1,500 m) to three plants and in corresponding control residential areas of the same district. Nine hundred and seventy-nine residents were questioned about the odor annoyance in their vicinity. An instrument measuring somatic complaints (SOMS 2 acc. Rief et al., 2001) was used to determine the unexplained somatic symptoms of the past two years and a gender-independent Total Complaint Index (TCI) was calculated. The percentages of study population reporting somatic symptoms were higher in all six samples in comparison with the German population (Rief et al., 2001) and in samples living near composting sites compared to the corresponding control samples. The study sample living close to site A (exposed to bioaerosols and odor annoyance) had the highest rates of complaints. A difference could be seen in comparison to the corresponding control sample (TCI: p[Anear vs. Acontrol] = 0.001; Mann-Whitney). In this group breathlessness was reported more than twice as often as in the other three samples. Out of the five most frequently reported symptoms four corresponded to the five complaints the German population reports most frequently in all groups. Nausea was the fifth most reported symptom in both samples reporting annoying residential odors (Anear and Bnear). The type of somatic symptoms reported most often was influenced little by environmental odors and medically relevant bioaerosol concentrations, except for nausea in context with annoying residential odors. As expected frequency of reporting general somatic symptoms was influenced by the perceived environment near the three composting sites. Concerning the sum of bodily complaints (TCI) though, this was only significant in the group exposed to medically relevant concentrations of residential outdoor bioaerosols, which was accompanied by high rates for breathlessness. The SOMS2 was able to mirror measurable, medically relevant environmental exposures in study groups and showed fewer changes concerning annoying or presumed environmental exposures.

Assessing the environmental health relevance of cooling towers--a systematic review of legionellosis outbreaks.

Bioaerosols from cooling towers are often suspected to cause community-acquired legionellosis outbreaks. Although Legionella infections can mostly be assigned to the emission sources, uncertainty exists about the release and distribution into the air, the occurrence of the respirable virulent form and the level of the infective concentration. Our study aimed to evaluate studies on legionellosis outbreaks attributed to cooling towers published within the last 11 years by means of a systematic review of the literature. 19 legionellosis outbreaks were identified affecting 12 countries. Recurring events were observed in Spain and Great Britain. In total, 1609 confirmed cases of legionellosis and a case-fatality rate of approximately 6% were reported. Duration of outbreaks was 65 days on average. For diagnosis the urinary antigen test was mainly used. Age, smoking, male sex and underlying diseases (diabetes, immunodeficiency) could be confirmed as risk factors. Smoking and underlying diseases were the most frequent risk factors associated with legionellosis in 11 and 10 of the 19 studies, respectively. The meteorological conditions varied strongly. Several studies reported a temporal association of outbreaks with inadequate maintenance of the cooling systems. A match of clinical and environmental isolates by serotyping and/or molecular subtyping could be confirmed in 84% of outbreaks. Legionella-contaminated cooling towers as environmental trigger, in particular in the neighbourhood of susceptible individuals, can cause severe health problems and even death. To prevent and control Legionella contamination of cooling towers, maintenance actions should focus on low-emission cleaning procedures of cooling towers combined with control measurements of water and air samples. Procedures allowing rapid detection and risk assessment in the case of outbreaks are essential for adequate public health measures. Systematic registration of cooling towers will facilitate the identification of the source of outbreaks and help to shorten their duration.

Physicians appeals on the dangers of mobile communication--what is the evidence? Assessment of public health data.

In October 2002 German physicians appealed to persons in the field of health care, politicians and the public with "great concern" ("Freiburger Appell", "Appeal of Freiburg") claiming "soaring incidences of symptoms and diseases in the general population" to be causally related to the "commence of radio (wave) burden", i.e. due to mobile radio technology. This first example was followed by several further appeals published nationally and Europe-wide up until today. The aim of the present paper is an evaluation of the scientific literature and databases to check incidence and prevalence of symptoms and diseases stated in the appeals to have "dramatically increased" or to have appeared in "greater frequency" in adults. If the allegations were true a clear time-trend should show up since the start of widely-used mobile communication technology. The following health conditions were considered: Alzheimer's disease, dementia, sleep disturbances, tinnitus, cerebrovascular disease, ischemic heart-diseases, headache, migraine. Data on the incidence of these conditions were assessed from 1993 through at least 2005. For this, a systematic search by keywords was performed in the online-database of the National Library of Medicine (pubmed) and other national and international (European and US) databases. For none of the considered symptoms or diseases a "dramatic increase" was found to have occurred since 1993. Because of the different diagnoses and terms used in the studies, direct comparability is somewhat difficult. Indeed, with the data available no time related increases and surely no "dramatic increase" can be identified, even if the limited comparability is considered. This analysis strongly suggests that the allegations of the quoted appeals are not supported by public health data.