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- Nielsen, Jörn, et al.
(författare)
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Dust-free bleaching powder may not prevent symptoms in hairdressers with bleaching-associated rhinitis
- 2016
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Ingår i: Journal of Occupational Health. - 1341-9145 .- 1348-9585. ; 58:5, s. 470-476
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Tidskriftsartikel (refereegranskat)abstract
- Objective: Hairdressers have an increased risk for airway symptoms especially when using hairbleaching powder containing persulfate. To minimize exposure, dust-free bleaching powder (DFP) has been made available. We studied the effects of regular powder (RP) or DFP on the airway symptoms of hairdressers with hair-bleaching associated rhinitis. Methods: Twelve hairdressers each performed three hair-bleachings on a wig in an exposure chamber. Half of the subjects used RP and half used DFP. Exposure to persulfate and ammonia was measured. Before and after each bleaching, the participants stated their degree of airway symptoms on a visual analogue scale. Nasal lavage and blood were sampled before exposure, after the last bleaching, and in the morning after exposure to measure inflammatory markers. Results: Exposure to persulfate was higher when using RP compared to DFP, 22 (11-55) vs. 12 (8- 13) μg/m3; median (min-max). Exposure to ammonia did not differ between the groups. Both groups reported an increase in asthma-like symptoms and this increase was significant. Neutrophils, lymphocytes, and monocytes increased after exposure in both groups; monocytes decreased the day after. In nasal lavage, IL-8 was increased the morning after for both types of powder, and the increase was significant in the total group. IL-6 increased immediately after exposure and the day after only in the group using RP. Conclusions: Although DFP powder emits lower levels of persulfate, effects are still elicited in symptomatic hairdressers.
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| 8. |
- Nilsson, Patrik, et al.
(författare)
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Characterization of Hairdresser Exposure to Airborne Particles during Hair Bleaching.
- 2016
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Ingår i: Annals of Occupational Hygiene. - : Oxford University Press (OUP). - 1475-3162 .- 0003-4878. ; 60:1, s. 90-100
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Tidskriftsartikel (refereegranskat)abstract
- Respiratory symptoms among hairdressers are often ascribed to the use of bleaching powders that contain persulfate salts. Such salts can act as allergens and airway irritants but the mechanisms behind the negative health effects are not fully known. In order to understand why some hairdressers experience respiratory symptoms during, and after, sessions of hair bleaching, it is of importance to characterize how exposure occurs. In this work we used time and particle size resolved instrumentation with the aim to measure the concentration of particles that hairdressers are exposed to during sessions of hair bleaching. We also used filter samples to collect particles for quantitative determination of persulfate (S2O8 (2-)) content and for analysis by light microscopy. Two different types of bleaching powders were used, one marked as dust-free and one without this marking (denoted regular). The time resolved instrumentation revealed that particles <10 µm were emitted, specifically when the regular powder was prepared and mixed with hydrogen peroxide. In contrast to other research our work also revealed that supercoarse particles (>10 µm) were emitted during application of the bleaching, when both the regular and the dust-free powders were used. The measured level of persulfate, sampled in the breathing zone of the hairdressers, was on average 26 µg m(-3) when the regular powder was used and 11 µg m(-3) when the dust-free powder was used. This indicates that use of dust-free powder does not eliminate exposure to persulfates, it only lowers the concentration. We show that the site of sampling, or position of the hairdresser with regards to the hair being bleached, is of high importance in the determination of persulfate levels and exposure. This work focuses on the physical and chemical characterization of the particles released to the air and the results are important for accurate exposure assessments. Accurate assessments may in turn lead to a better understanding of why some hairdressers experience respiratory symptoms from hair bleaching sessions.
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| 9. |
- Omelekhina, Yuliya, et al.
(författare)
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Chemical composition of airborne particles inside and outside a Swedish residence assessed by real time aerosol mass spectrometry
- 2018
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- A number of deleterious health effects have been identified from exposure to outdoor air-borne particulate matter. This issue is complicated by the fact that people are spending most of the time indoors, where particles of both indoor and outdoor origin are present. The aim of this work was to assess the differences in particle chemical composition inside and outside of the residence and gain better understanding about major contributors to the observed levels indoors. Our results showed that indoor aerosol mass concentration exceeded the outdoor values mainly due to the contribution of organic matter from indoor sources during the presence of the residents at home. The infiltration of chemical species from outdoors was not the major factor determining indoor aerosol mass concentration and chemical composition.1 INTRODUCTIONConsidering that on average in developed countries we spend about 65% (Brashe and Bis-chof) of our time in private homes, the understanding of exposure to particulate matter in homes is important, yet knowledge is sparse. Indoors, aerosol concentrations come from in-door sources, infiltrate from outdoors and can be formed through reactions of gas-phase precursors emitted both indoors and outdoors. Several characteristics and processes influence the properties of aerosols indoors, among them: active indoor sources (presence of occupants), outdoor aerosol characteristics, physicochemical particle transformations during infiltration and while indoors, ventilation type, tightness of the building envelope and particle deposition (Morawska et al., 2013). In this study, we aimed to investigate the differences in chemical composition between aerosols inside and outside of the residence and to identify the origin of major contributors to the particle levels indoors. We report preliminary results of measure-ments for a 1-month period in an occupied apartment. 2 METHODS Indoor and outdoor measurements were performed in an occupied residence in Malmö, Swe-den. It was a naturally ventilated four-room apartment (292 m3), located in a three-store con-crete building surrounded by a green zone. A Time-of-Flight Aerosol Mass Spectrometer (AMS, DeCarlo et al., 2006) was used to measure particle mass loadings and size-resolved mass distributions (size range of 50-500 nm) of indoor and outdoor organic, sulphate, nitrate, ammonium and chloride aerosols. An automatic switching valve alternated between indoor and outdoor lines with a time interval of 20 and 10 minutes in indoor and outdoor air, respectively. Both sampling lines were mounted at the ground floor level and led to the basement where the aerosol was dried and measured by AMS. Calculated residence time of the particles in line was 1.5 minutes. Indoor sampling line was heated and insulated, additional carrier flow was used to lower the resi-dence time. Indoor to outdoor (I/O) ratios were calculated and used for comparisons of differences in aerosol composition inside and outside of the residence.3 RESULTS AND DISCUSSIONThe results showed higher total average mass concentration indoors (12.9 μg/m3) compared to outdoors (5.4 μg/m3) during entire measuring period. Indoor to outdoor (I/O) ratio for or-ganics was 6.7, for nitrate 0.3, for sulphate 0.5, for ammonium 0.2 and for chloride 0.2. Or-ganic matter was the dominant species indoors, accounting for most of the total mass (92 %) due to contribution from indoor sources during the time when residents were at home, i.e. occupancy period. Figure 1A illustrates elevated particle mass concentrations when different indoor activities took place. Effects of penetration and phase change of the outdoor particle species can be observed during non-occupancy period (Figure 1B). Non-occupancy time ac-counted only to 7 % of the total monitoring period and did not have much influence on parti-cle mass concentration indoors.Ammonium nitrate (NH4NO3) and ammonium chlorine (NH4Cl) are semi-volatile aerosol species, thus, gas-to-particle partitioning depends on temperature, relative humidity, particle size and gas phase concentrations of ammonia, nitric acid and chlorine as outdoor air is transported indoors (Mozurkewich, 1993; Lunden et al., 2004). Such phase transitions are especially pronounced in the cold period of the year. The outdoor weather conditions varied during this time with Tout from -8.8 to 9.7 °C and RHout from 58 to 100 %. Indoors, Tin ranged from 20 to 26.1 °C and RHin from 27 to 50 %. Low value of I/O ratio for non-volatile sul-phate can be explained by dominating of the outdoor sources and reflects reduced infiltra-tion. The outdoor total mass concentration in urban sites measured by TOF-AMS was comparable with previous studies (Crippa et al., 2014; Jimenez et al., 2009). Some local sources, such as emissions from fireplaces by neighbours and from adjacent fast food restaurants could have contributed to the outdoor loadings. 4 CONCLUSIONSIn general, the differences in chemical composition of particles found indoors and outdoors becomes apparent from the results. Levels of organics in indoor environments were mainly influenced by indoor sources, thus, these should not be neglected when considering possible health effects. Additionally, reduced air exchange rate in the apartment in Scandinavia during wintertime enhanced aerosol accumulation and physicochemical transformation indoors.ACKNOWLEDGEMENTThis work was financed by the Swedish Research Council FORMAS (Project Dnr 942-2015-1029).
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| 10. |
- Omelekhina, Yuliya, et al.
(författare)
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Chemically-resolved particle mass composition in a Swedish residence assessed by a Time-of-Flight Aerosol Mass Spectrometer
- 2018
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Ingår i: ; , s. 1-2
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- A number of deleterious health effects have been identified from exposure to outdoor airborne particulate matter. Given that in developed countries we spend majority of our time indoors, in private homes about 65 % (Brashe et al., 2005), the understanding of this exposure is important, yet knowledge is sparse. Particle levels indoors are affected by indoor sources, infiltration from outdoors or particle mass forms through reactions of gas-phase precursors emitted both indoors and outdoors (Morawska et al., 2013). The aim of this work was to characterize a chemical composition of particle mass indoors, and to gain a better understanding about major contributors to the observed indoor levels with Aerosol Mass Spectrometer. We aimed to identify mass spectral signatures of specific indoor sources. This is preliminary results of measurements for a 1-month period.Indoor and outdoor measurements were performed in an occupied residence in Malmö, Sweden. It was a naturally ventilated four-room apartment (292 m3), located in a three-store concrete building surrounded by a green zone. A Time-of-Flight Aerosol Mass Spectrometer (DeCarlo et al., 2006) was used to measure particle mass loadings and size-resolved mass distributions (50-500 nm) of indoor and outdoor chemical species. An automatic switching valve alternated between indoor and outdoor lines with a time interval of 20 and 10 minutes, respectively. Both sampling lines were mounted at the ground floor level and led to the basement where the aerosols were dried and measured by AMS. Our results showed higher total average mass concentration indoors (12.9 μg/m3) compared to outdoors (5.4 μg/m3) over the entire measuring period. Indoor to outdoor (I/O) ratio for organics was 6.7, for sulphate 0.5, for nitrate 0.3, for ammonium 0.2 and for chloride 0.2. The dominant species indoors was organic matter, accounting for most of the total particle mass (92 %) due to contribution from indoor sources and from outdoor infiltration. Non-volatile sulphate showed reduced infiltration from outdoors. From comparison of outdoor and indoor concentrations of ammonium nitrate and ammonium chloride, which are sensitive to temperature and RH (Lunden et al., 2004), a clear reduction due to phase change was observed upon outdoor-to-indoor transport. We investigated different organic mass spectra for indoor events as recorded in the logbooks. The main events analysed comprised from various types of cooking and candle burning. They showed to emit different proportions of hydrocarbons and oxygenated organic species, which yield CxHy+, CxHyO+, CxHyOz+ ion classes. The relative intensity of CxHy+ ion class out of the total organic signal during frying was 65-68 %, deep-frying ~ 68 %, baking 60-70 %, other forms of cooking 60-68 %, candle burning 60-70%. For CxHyO+ ion class: frying 25-30 %, deep-frying 24-25 %, baking 27-32 %, cooking 25-31 %, candle burning 20-30 %. For CxHyOz+ ion family: frying 7-8%, deep-frying 7-8 %, cooking and baking 6-9 %, candle burning 6-8 %. The observed variability in organic mass spectral signature for different indoor sources should allow us to apply Positive Matrix Factorization for source apportionment and processes occurring in indoor air. This will help us to gain a better understanding about main contributors to the observed loading indoors.
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