Barbara Kolarik

The Association between Phthalates in Dust and Allergic Diseases among Bulgarian Children

Background Recent studies have identified associations between the concentration of phthalates in indoor dust and allergic symptoms in the airways, nose, and skin. Objectives Our goal was to investigate the associations between allergic symptoms in children and the concentration of phthalate esters in settled dust collected from children’s homes in Sofia and Burgas, Bulgaria. Methods Dust samples from the child’s bedroom were collected. A total of 102 children (2–7 years of age) had symptoms of wheezing, rhinitis, and/or eczema in preceding 12 months (cases), and 82 were nonsymptomatic (controls). The dust samples were analyzed for their content of dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DnBP), butyl benzyl phthalate (BBzP), di(2-ethylhexyl) phthalate (DEHP), and di-n-octyl phthalate (DnOP). Results A higher concentration of DEHP was found in homes of case children than in those of controls (1.24 vs. 0.86 mg/g dust). The concentration of DEHP was significantly associated with wheezing in the preceding 12 months (p = 0.035) as reported by parents. We found a dose–response relationship between DEHP concentration and case status and between DEHP concentration and wheezing in the preceding 12 months. Conclusions This study shows an association between concentration of DEHP in indoor dust and wheezing among preschool children in Bulgaria.

PVC--as flooring material--and its association with incident asthma in a Swedish child cohort study.

UNLABELLED The Dampness in Buildings and Health study (DBH) started in the year 2000 in Värmland, Sweden, with a baseline questionnaire sent to all children (n = 14,077) aged 1-6. Five years later, a follow-up questionnaire was sent to the children who were 1-3 years at baseline. A total of 4779 children participated in both the baseline and the follow-up studies and constitute the study population in this cohort study. The aim of this study was to examine the association between exposure to PVC-flooring in the childs and parents bedroom in homes of children aged 1-3 and the incidence of asthma, rhinitis, and eczema during the following 5-year period. Adjusted analyses showed that the incidence of asthma among children was associated with PVC-flooring in the childs bedroom (AOR 1.52; 95% CI 0.99-2.35) and in the parents bedroom (1.46; 0.96-2.23). The found risks were on borderline of significance and should therefore be interpreted with caution. There was further a positive relationship between the number of rooms with PVC-flooring and the cumulative incidence of asthma. PVC-flooring was found to be a stronger risk factor for incident asthma in multifamily homes when compared with single-family houses and in smoking families compared with non-smoking families and in women. PRACTICAL IMPLICATIONS These longitudinal data from the DBH study found an association between the presence of PVC-flooring in the home and incident asthma in children. However, earlier results from the DBH study have shown that PVC-flooring is one important source for phthalates in indoor dust, and exposure to such phthalates was found to be associated with asthma and allergy among children. This emphasizes the need for prospective studies that focus on the importance of prenatal and neonatal exposure to phthalates in the development of asthma and allergy in children.

Emission of Isothiazolinones from Water-Based Paints

The isothiazolinone preservatives methylisothiazolinone (MI), methylchloroisothiazolinone (MCI), and benzisothiazolinone (BIT) are used in a wide variety of products including paint and cosmetics, and they are known to cause allergic contact dermatitis. Among painters they are one of the most common causes of contact dermatitis. Furthermore, they are all volatile, and severe reactions caused by emissions of especially MI from paint have been reported recently. In this study the concentrations of MI, BIT, and MCI in water-based paint were analyzed by LC-MS-MS, and the emissions from the paints were measured in climate chambers and in an apartment. Nineteen paints were analyzed for the content of MI, MCI, and BIT. All 19 paints contained MI, 16 contained BIT, and 4 contained MCI. In the chamber experiment emission of MI peaked within hours of application but then continued at a slow rate for more than 42 days. MCI was emitted more slowly and peaked after several days. BIT emissions were all around the limit of detection. In the apartment we were able to detect emission of MI several days after application. Long lasting evaporation and thus chronic exposure give credibility to the clinical observations that MI can be an important cause of airborne contact dermatitis among painters and consumers.

Plasma polychlorinated biphenyls in residents of 91 PCB-contaminated and 108 non-contaminated dwellings-an exposure study.

BACKGROUND In the1950s-1970s polychlorinated biphenyls (PCBs) were used in several countries as plasticizers in elastic sealants in buildings. OBJECTIVE The primary objective was to study whether residents of PCB-contaminated dwellings had higher plasma levels of PCBs than their neighbours in non-contaminated dwellings. The secondary objective was to study possible associations between concentrations of PCBs in the indoor air and in the plasma of residents. METHODS Stratified cross-sectional study of residents of a housing estate with four sections, of which only one section had PCB-containing sealants. The determination of 27 PCB congeners in plasma was performed among 134 exposed and 139 non-exposed residents. Air measurements were conducted in 104 flats. RESULTS Significant differences in plasma PCBs between exposed versus non-exposed were found for most of the lower chlorinated and many of the higher chlorinated congeners. The median of sum of 27 PCBs was approximately four times higher in exposed compared with non-exposed residents. The elevated PCB concentrations persisted in multivariable analyses controlling for relevant cofactors. We found significant correlations between PCB indoor air concentrations and the PCB concentration in the plasma of the residents for ten of the lower chlorinated congeners. CONCLUSION Our study confirms that indoor air exposure to PCBs from PCB containing sealants may result in a considerable internal PCBs exposure of the residents. For the first time we were able to demonstrate that the internal exposure to low chlorinated PCBs is significantly associated with the indoor air concentration of these congeners.

Nitric oxide in exhaled and aspirated nasal air as an objective measure of human response to indoor air pollution

UNLABELLED The concentration of nitric oxide (NO) in exhaled and aspirated nasal air was used to objectively assess human response to indoor air pollutants in a climate chamber exposure experiment. The concentration of NO was measured before exposure, after 2, and 4.5 h of exposure, using a chemiluminescence NO analyzer. Sixteen healthy female subjects were exposed to two indoor air pollutants and to a clean reference condition for 4.5 h. Subjective assessments of the environment were obtained by questionnaires. After exposure (4.5 h) to the two polluted conditions a small increase in NO concentration in exhaled air was observed. After exposure to the reference condition the mean NO concentration was significantly reduced compared to pre-exposure. Together these changes resulted in significant differences in exhaled NO between exposure to reference and polluted conditions. NO in nasal air was not affected by the exposures. The results may indicate an association between polluted indoor air and subclinical inflammation. PRACTICAL IMPLICATIONS Measurement of nitric oxide in exhaled air is a possible objective marker of subclinical inflammation in healthy adults.

Concentrations of Formaldehyde in new Danish Residential Buildings in Relation to WHO Recommendations and CEN Requirements

It is uncertain if current Danish legislation regarding emission of formaldehyde from wood-based panels could assure that concentrations of formaldehyde in the indoor air of buildings containing the material would meet the World Health Organization (WHO) guideline. This is of particular concern since the recent recognition by International Agency for Research on Cancer that formaldehyde is carcinogenic to humans. Therefore, the purpose of this study was to determine whether residents of newly built Danish residential houses could be exposed to safe levels of formaldehyde. Geometric mean concentration of formaldehyde measured in 20 residential buildings was 0.04 mg m−3. Formaldehyde concentrations in two buildings (10%) exceeded the WHO guideline value. In order to explain the relatively high concentrations, a second phase was performed. The aim was to identify the significant formaldehyde sources and to discuss the source strength in relation to field measurements and WHO guidelines. The results showed wide differences between the materials tested, but all steady-state concentrations were below the European standard requirement for class E1. These measurements formed the basis for model calculations of possible resulting concentrations in residential rooms, suggesting that indoor concentrations above the WHO maximum limit could occur. The calculations applied a worst case scenario with all surfaces covered with materials emitting the maximum permissible amount of formaldehyde show indoor concentrations as high as 0.6 mg m−3.

Investigation of the importance of tertiary contamination, temperature and human behaviour on PCB concentrations in indoor air

High concentrations of polychlorinated biphenyls (PCBs) can still be measured in indoor air in many buildings built or renovated within the period from approximately 1950 until the late seventies. The increasing evidence of the importance of indoor exposure to PCBs has led to the initiation of remediation actions in many countries. Understandably, primary sources with original PCB content have been the main focus of the actions. However, removal of primary sources alone has shown to be insufficient in decreasing the high indoor PCB concentrations in contaminated buildings. The aim of this study was to investigate the importance of tertiary PCB sources to indoor air concentrations and identify predictors of PCB air concentrations in contaminated buildings. In this study, 24 PCB congeners were measured in the indoor air of 83 contaminated apartments as well as in sealants sampled in a random subset of 20 apartments. The sealants were identified to be the primary source containing the original PCBs. For total PCBs, the median air concentration was 859 ng/m3 and the median concentration in contaminated sealants was 16.5% by weight. Analyses performed in the present study indicate that the influence of tertiary sources on indoor air concentrations may be substantial and that removal of tertiary sources may be needed when performing PCB remediation in buildings.

Residential ozone and lung function in the elderly

Ground level ozone arises primarily from traffic, it is a powerful oxidant and its primary target organ is the lung. Most epidemiological studies reporting the health effects of ozone have estimated individual exposure from measurements obtained from outdoor monitors but surrogates of personal exposure may not adequately reflect personal exposures. Also, the main focus has been on infants and children. Our purpose was to assess associations between urban background ozone and indoor residential ozone levels as well as to investigate the effects of indoor residential ozone on lung function in 51 elderly non-smokers. Indoor ozone was measured passively in homes, while urban background outdoor ozone was monitored continuously at a fixed monitoring station located on the roof of the 20-m high university H.C. Ørsteds campus building in a park area. Lung function was measured at baseline as well as on three consecutive occasions, for each subject. The mean residential ozone levels were 1.33 ppb, and mean outdoor urban background levels were 27 ppb. Outdoor urban background ozone levels were not consistently associated with residential ozone. No significant changes in lung function were detected in association with residential ozone among healthy participants. In this study, we were unable to detect significant changes in lung function in association with increased levels of residential ozone amongst healthy elderly non-smokers.

Design Requirements for Sensing and Detoxification Devices to be Used in Large Public Spaces. Literature Review on Typical Pollutants and Their Concentrations

This work is a part of the NANOSECURE integrated project, supported by the European Commission under Framework Programme 6, with the objective to use nanotechnology in developing sensing and detoxification devices. Besides being sensitive, flexible, compact and inexpensive, it is important that the sensors do not respond to normal indoor air pollutants in their typical concentrations, as false-positive signals can have serious consequences. The purpose of this paper is to list typical indoor air pollutants and indicate ranges of concentrations in which they normally occur. Among others, these results may draw designers’ and manufacturers’ attention to the importance of chemical selectivity, sufficient capacity and robustness to withstand normal exposures in buildings. The main focus is on assembly buildings, airport terminals, and train and metro stations, as spaces in these buildings can be especially endangered by attacks using chemical or biological agents due to their size and population density. The literature review shows lack of information on concentrations of chemical and biological pollutants in these buildings. It also points out a need for calibration and testing in both laboratory environments with clean and well-defined air quality and in atmospheres with typical and often complex compositions.