Vacuum Sampling of Settled Dust for Lead Analysis

In this study, we measured the occurrence of organophosphate esters (OPEs) and phthalates in the settled dust (floor and air conditioner filter dust) and in suspended particulate matter (PM10) from different microenvironments (households (n = 20), offices (n = 10) and hotels (n = 10)) of Jeddah, Saudi Arabia. Bis (2-Ethylhexyl) phthalate (DEHP) was the major pollutant (contributing >85% of total chemicals burden) in all types of indoor dust with a concentration up to 3,901,500 ng g−1. While dibutyl phthalate (DBP) and DEHP together contributed >70% in PM10 (1900 ng m−3), which indicate PM10 as a significant source of exposure for DBP and DEHP in different Saudi indoor settings. Tris (1-chloro-2-propyl) phosphate (TCPP) was the major OPE in PM10 with a concentration of up to 185 ng m−3 and the occurrence of OPEs in indoor dust varied in studied indoor settings. The estimated daily intake (EDI) of studied chemicals via dust ingestion and inhalation of PM10 was below the reference dose (RfD) of individual chemicals. However, estimated incremental lifetime cancer risk (ILCR) with moderate risk (1.5 × 10−5) for Saudi adults and calculated hazardous index (HI) of >1 for Saudi children from DEHP showed a cause of concern to the local public health.

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Melinacidin-Producing Acrostalagmus luteoalbus, a Major Constituent of Mixed Mycobiota Contaminating Insulation Material in an Outdoor Wall

Pathogens ◽

10.3390/pathogens10070843 ◽

2021 ◽

Vol 10 (7) ◽

pp. 843

Author(s):

(Aino) Maria A. Andersson ◽

Johanna Salo ◽

Raimo Mikkola ◽

Tamás Marik ◽

László Kredics ◽

...

Keyword(s):

Air Quality ◽

Indoor Air Quality ◽

Indoor Air ◽

Mass Spectrometry Analysis ◽

Major Constituent ◽

Bioactive Metabolites ◽

Its Sequencing ◽

Insulation Material ◽

Settled Dust ◽

Aspergillus Section

Occupants may complain about indoor air quality in closed spaces where the officially approved standard methods for indoor air quality risk assessment fail to reveal the cause of the problem. This study describes a rare genus not previously detected in Finnish buildings, Acrostalagmus, and its species A. luteoalbus as the major constituents of the mixed microbiota in the wet cork liner from an outdoor wall. Representatives of the genus were also present in the settled dust in offices where occupants suffered from symptoms related to the indoor air. One strain, POB8, was identified as A. luteoalbus by ITS sequencing. The strain produced the immunosuppressive and cytotoxic melinacidins II, III, and IV, as evidenced by mass spectrometry analysis. In addition, the classical toxigenic species indicating water damage, mycoparasitic Trichoderma, Aspergillus section Versicolores, Aspergillus section Circumdati, Aspergillus section Nigri, and Chaetomium spp., were detected in the wet outdoor wall and settled dust from the problematic rooms. The offices exhibited no visible signs of microbial growth, and the airborne load of microbial conidia was too low to explain the reported symptoms. In conclusion, we suggest the possible migration of microbial bioactive metabolites from the wet outdoor wall into indoor spaces as a plausible explanation for the reported complaints.

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Associations among phthalate exposure, DNA methylation of TSLP, and childhood allergy

Clinical Epigenetics ◽

10.1186/s13148-021-01061-1 ◽

2021 ◽

Vol 13 (1) ◽

Author(s):

Wan-Ru Wang ◽

Nai-Tzu Chen ◽

Nai-Yun Hsu ◽

I-Ying Kuo ◽

Hsin-Wen Chang ◽

...

Keyword(s):

Dna Methylation ◽

Methylation Level ◽

Respiratory Symptoms ◽

Smoking Status ◽

Phthalate Esters ◽

Allergic Diseases ◽

Percentage Increase ◽

Phthalate Exposure ◽

Settled Dust ◽

Butyl Phthalate

Abstract Background Dysregulation of thymic stromal lymphopoietin (TSLP) expressions is linked to asthma and allergic disease. Exposure to phthalate esters, a widely used plasticizer, is associated with respiratory and allergic morbidity. Dibutyl phthalate (DBP) causes TSLP upregulation in the skin. In addition, phthalate exposure is associated with changes in environmentally induced DNA methylation, which might cause phenotypic heterogeneity. This study examined the DNA methylation of the TSLP gene to determine the potential mechanism between phthalate exposure and allergic diseases. Results Among all evaluated, only benzyl butyl phthalate (BBzP) in the settled dusts were negatively correlated with the methylation levels of TSLP and positively associated with children’s respiratory symptoms. The results revealed that every unit increase in BBzP concentration in the settled dust was associated with a 1.75% decrease in the methylation level on upstream 775 bp from the transcription start site (TSS) of TSLP (β = − 1.75, p = 0.015) after adjustment for child’s sex, age, BMI, parents’ smoking status, allergic history, and education levels, PM2.5, formaldehyde, temperature; and relative humidity. Moreover, every percentage increase in the methylation level was associated with a 20% decrease in the risk of morning respiratory symptoms in the children (OR 0.80, 95% CI 0.65–0.99). Conclusions Exposure to BBzP in settled dust might increase children’s respiratory symptoms in the morning through decreasing TSLP methylation. Therefore, the exposure to BBzP should be reduced especially for the children already having allergic diseases.

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Geographic source estimation using airborne plant environmental DNA in dust

Scientific Reports ◽

10.1038/s41598-021-95702-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Chelsea Lennartz ◽

Joel Kurucar ◽

Stephen Coppola ◽

Janice Crager ◽

Johanna Bobrow ◽

...

Keyword(s):

Plant Species ◽

Fungal Spores ◽

Geographic Origin ◽

Microscopic Analysis ◽

Environmental Dna ◽

Dust Sample ◽

Accurate Estimate ◽

Plant Parts ◽

Settled Dust ◽

Great Utility

AbstractInformation obtained from the analysis of dust, particularly biological particles such as pollen, plant parts, and fungal spores, has great utility in forensic geolocation. As an alternative to manual microscopic analysis of dust components, we developed a pipeline that utilizes the airborne plant environmental DNA (eDNA) in settled dust to estimate geographic origin. Metabarcoding of settled airborne eDNA was used to identify plant species whose geographic distributions were then derived from occurrence records in the USGS Biodiversity in Service of Our Nation (BISON) database. The distributions for all plant species identified in a sample were used to generate a probabilistic estimate of the sample source. With settled dust collected at four U.S. sites over a 15-month period, we demonstrated positive regional geolocation (within 600 km2 of the collection point) with 47.6% (20 of 42) of the samples analyzed. Attribution accuracy and resolution was dependent on the number of plant species identified in a dust sample, which was greatly affected by the season of collection. In dust samples that yielded a minimum of 20 identified plant species, positive regional attribution was achieved with 66.7% (16 of 24 samples). For broader demonstration, citizen-collected dust samples collected from 31 diverse U.S. sites were analyzed, and trace plant eDNA provided relevant regional attribution information on provenance in 32.2% of samples. This showed that analysis of airborne plant eDNA in settled dust can provide an accurate estimate regional provenance within the U.S., and relevant forensic information, for a substantial fraction of samples analyzed.

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Office Environment Syndrome Study: Part II

Proceedings of the Human Factors and Ergonomics Society Annual Meeting ◽

10.1177/154193129804200804 ◽

1998 ◽

Vol 42 (8) ◽

pp. 639-642

Author(s):

Alan Hedge ◽

William A. Erickson

Keyword(s):

Case Reports ◽

Case Control ◽

Self Report ◽

Respirable Dust ◽

Diary Study ◽

Climate Conditions ◽

Office Environment ◽

Work Posture ◽

Computer Mouse ◽

Settled Dust

A longitudinal self-report diary study of SBS cases and controls identified from buildingwide surveys of 4 office buildings is described. Self-report diaries were distributed to a total of 214 workers in the 4 buildings, and complete returns were obtained for 123 workers (57% return rate). Climate conditions (CO, CO2, formaldehyde, respirable dust mass (PM3.5) and particulate counts (0.3 μm, 0.5 μm, 1 μm, 5 μm), settled dust, air temperature, %RH, illuminance) were measured at each workstation. Ergonomic factors (observed work posture, office type, desk paper coverage, desk clutter, computer, mouse, keyboard tray, age of chair, chair arms, and plants, were measured at each workstation. Results showed no differences in prevailing climate conditions measured at case/control workstations. However, case reports of symptoms and environment conditions generally were worse than those for controls, and these reports showed periodicity, peaking late each day. The differences between reports by cases and controls generally remained consistent throughout the duration of the study.

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Hot metal desulfurization by marble waste and fluorspar

Rem Revista Escola de Minas ◽

10.1590/s0370-44672012000200012 ◽

2012 ◽

Vol 65 (2) ◽

pp. 233-240 ◽

Cited By ~ 2

Author(s):

Felipe Nylo de Aguiar ◽

Felipe Fardin Grillo ◽

Jorge Alberto Soares Tenório ◽

José Roberto de Oliveira

Keyword(s):

Chemical Composition ◽

Chemical Analysis ◽

Pig Iron ◽

Hot Metal ◽

Industrial Mixture ◽

Desulfurization Process ◽

Hot Metal Desulfurization ◽

Vacuum Sampling ◽

Marble Waste

The objective of this paper is to present an analysis of the use of residual marble mixtures in the pig iron desulfurization process. The study involved the use of: marble waste, fluorspar, lime, and hot metal. Four mixtures were made and added to a liquid hot metal - with known chemical composition - at a temperature of 1450ºC. The mass of each element was calculated from its chemical analysis and compared with an industrial mixture. All of the four mixtures used in the experiments were stirred by a mechanical stirrer. Samples were collected by vacuum sampling for times of 5, 10, 15, 20, and 30 minutes, and analysis was performed to check sulfur variation in the bath with time. The results were analyzed and they verified that it was possible to use marble waste as a desulfurizer.

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