Arsen i jego związki nieorganiczne. Metoda oznaczania w powietrzu na stanowiskach pracy

Arsenic is a chemical element classified as metalloids (semi-metals). Some arsenic compounds have been classified (according to CLP) as carcinogens, causing cancers of skin, respiratory system, liver and leukemia. In the industry, workers are exposed to arsenic and its compounds in its extraction, in metallurgy of non-ferrous metal ores, in metal refining processes, in the production of alloys, semiconductors, pigments and insecticides. In Poland, binding value of the hygienic standard (NDS) at workplace air, for the inhalable fraction of arsenic aerosol and its inorganic compounds, converted into As is 0.01 mg/m3 . A determination method has been developed that enables the determination of this substance in the air of 0.1 − 2 values of the hygiene standard, in accordance with the requirements of Standard PN-EN 482. Arsenic is determined with the atomic absorption spectrometry with electrothermal atomization (ET-AAS), in the concentration range of 5.00 − 100.0 μg/l which allows the determination of arsenic and its compounds in workplace air in the range of 0.0010 − 0.021 mg/m3 (for 480-L air sample). The presented procedure enables the determination of this substance with the use of individual dosimetry. This article discusses the problems of occupational safety and health, which are covered by health sciences and environmental engineering.

Detection of SARS-CoV-2 in Exhaled Breath from Non-Hospitalized COVID-19-Infected Individuals: A Proof-of-Concept Study

Background: The diagnosis of COVID-19 is based on detection of SARS-CoV-2 in oro-/nasopharyngel swabs, but because of uncomfortness and minor risk for the tested individual during the swab procedure, detection of SARS-CoV-2 has been investigated in other biological matrixes.Methods: In this proof-of-concept study, confirmed SARS-CoV-2-infected individuals performed a daily air sample through five days. Air samples were obtained through a non-invasive electrostatic air sampler. Detection of SARS-CoV-2 RNA were determined with qRT-PCR. The association of positive samples with clinical characteristics was evaluated through mixed-effect models.Results: We obtained 665 air samples from 111 included patients with confirmed SARS-CoV-2 infection. Overall, 52 individuals (46.8%) had at least one positive air sample, and 129 (19.4%) air samples were positive for SARS-CoV-2. Patients with symptoms or a symptom duration ≤ four days had significantly higher odds of having a positive air sample. Cycle threshold values were significantly lower in samples obtained ≤ 4 days from symptom onset. Neither variant of SARS-CoV-2 nor method of air sampling were associated with a positive air sample.Conclusion: We demonstrate that SARS-CoV-2 is detectable in human breath, and suggest further evaluation of air sampling considering the non-invasive, point-of-care method.

Aerobiology from an Inactive Pyrite Mine: the Genome Sequence of the Airborne Pseudomonas sp. Strain L5B5

Pseudomonas sp. strain L5B5 is an antimicrobial-producing bacterium isolated from an air sample collected in a pyrite mine in Lousal, Portugal. Genomic analyses predicted genes involved in virulence factors. Here, we report the complete genome sequence of this bacterium, which consists of a circular chromosome with a length of 6,811,662 bp.

Application of gas analyzers for the control of fuel in the air environment of rocket and space industry enterprises

The presented work shows the necessity of organization of individual instrumental control of the content of rocket fuel and its products in the air of rocket-space industry enterprises. No accurate analysis of gas analyzers presented on the Russian market, providing individual instrumental control of concentrations of heptyl and its derivatives in the workplace air is available. Therefore, the task of express, automatic, selective and simultaneous monitoring of heptyl vapors and derivatives of its transformation in the air of industrial premises by one instrument and replacing the imported gas analyzers remains urgent. It is shown that the solution of the posed problem is possible on the basis of the optical absorption method. The requirements to be met by the gas analyzer are formulated. Approximate wavelengths at which simultaneous measurement of concentrations of heptyl and its derivatives in an air sample is possible have been determined. The ways of realization of individual gas analyzers having small mass-size characteristics are outlined. Structural schemes for infra-red gas analyzers have been proposed: multi-channel; single-channel (with frequency modulation of radiation). Tasks for further research are formulated.

A Selective Medium for the Recovery and Enumeration of Fomitopsis meliae, Causing Lemon Canker and Wood Rot

A selective medium (FMS medium) was developed for the isolation and quantification of Fomitopsis meliae, the causal agent of lemon canker and brown wood rot, from plants, soil, and air. The optimal concentration and combination of fungicides and antibiotics was evaluated to determine the most selective condition for growing F. meliae. The resultant composition of the medium (FMS) per litre (pH 3.5) was: 16 mg thiophanate-methyl, 8 mg dichloran, 5 mg 2-phenylphenol, 100 mg fluopyram, 0.5 mg fludioxonil, 100 mg chloramphenicol, 100 mg streptomycin, 15 g malt extract, 2.5 g mycological peptone, and 15 g agar. The fungus was successfully isolated and enumerated from air, soil and plant tissues using FMS medium. Furthermore, FMS medium almost completely inhibited the growth of other plant pathogenic fungi, soil and air saprophytes. This selectivity was high enough to estimate spore inoculum of F. meliae in an air sample or as a spore trapping device in commercial lemon orchards. FMS medium will be useful for studying epidemiology and management of F. meliae.

417. COVID-19 Aerostudy: Evaluation of SARS-CoV-2 Virus in the Air of Patients Hospitalized with COVID-19

Background At the onset of the COVID-19 pandemic, hospitals implemented infection control measures with limited data on predictors of nosocomial SARS-CoV-2 transmission. We aimed to quantify SARS-CoV-2 presence in an inpatient setting to understand nosocomial risk. Methods Patients admitted with confirmed SARS-CoV-2 infection at an urban academic hospital were enrolled. Demographic/clinical characteristics, a PCR nasal swab(NS), and air samples on filter media in the near- (< 6ft) and far-field ( >6ft) of each patient for 3.5 hours were collected. PCR was used to detect SARS-CoV-2 on filter media. Associations between clinical characteristics and presence of SARS-CoV-2 in air samples used Fisher’s exact and Wilcoxon rank sum tests. Results Of 52 subjects, 46% had no detectable virus by nasal swab on the day of sampling. Of 104 room air samples, 16% had detectable virus from 25% of rooms, including 10 near and 7 far field samples. Subjects with a positive room air sample had fewer days from symptom-onset compared with those with a negative air sample (median 6 vs. 8, p=0.24). Being on room air and having a nasal swab positive increased the odds of detecting virus in air samples but were not statistically significant. Conclusion A small number of air samples with detectable SARS-CoV-2 may suggest lower nosocomial risk than previously anticipated. Multiple subject and environmental factors may have contributed to this finding including patient source control masking, anti-viral therapies and HEPA filtration. The decreased association of virus in the air of those with more days of symptoms but with the need for supplemental oxygen may be related to what is now known about the COVID-19 inflammatory response after the infectious period. Disclosures All Authors: No reported disclosures

System Design for Early Detection of Explosive and Flammable Gas Leaks Using Mobile Robot in Confined Space

The presence of explosive or flammable gases in confined space may contribute towards accidents that threaten the workers safety and industrial progress. Conventionally, the existing instrument for gas detection in confined space is manually carried by humans whereby the workers or competence person itself were exposed directly to the gases. This project is aim to develop a prototype system to detect the presence of gases leak where the robotic system replaces humans to carry gas sensors. Users only need to maneuver the robot using a mobile phone to monitor the specific area that may have an explosive or flammable gas leak which includes Liquefied Petroleum Gas (LPG) and methane gases. The sensors will detect if a change in the gas concentration has exceeded a safety limit and will activate the alarm as an alert signal. The readings of gases as input signals were sent wirelessly to the Personal Computer (PC) as a user device for monitoring purposes. This prototype is successfully developed, tested and calibrated using the samples of LPG gas, methane, smoke and environment temperature. The result proved that the developed system is able to detect an air sample using selected gas sensors and display the data in graph form with live monitoring. This will contribute significantly to acquiring a new and alternative method using the system for detecting the presence of gases in confined space application.

Spatiotemporal variations of the δ(O₂/N₂), CO₂ and δ(APO) in the troposphere over the Western North Pacific

We analyzed air samples collected onboard a cargo aircraft C-130 over the western North Pacific from May 2012 to March 2020 for atmospheric δ(O2/N2) and CO2 amount fraction. We corrected for significant artificial fractionation of O2 and N2 caused by thermal diffusion during the air sample collection by using the simultaneously-measured δ(Ar/N2). The observed seasonal cycles of the δ(O2/N2) and atmospheric potential oxygen (δ(APO)) varied nearly in opposite phase to that of the CO2 amount fraction at all latitudes and altitudes. Seasonal amplitudes of δ(APO) decreased with latitude from 34 to 25° N, as well as with increasing altitude from the surface to 6 km by 50–70 %, while those of CO2 amount fraction decreased by less than 20 %. By comparing the observed values with the simulated δ(APO) and CO2 amount fraction values generated by an atmospheric transport model, we found that the seasonal δ(APO) cycle in the middle troposphere was modified significantly by a superposition of the northern and southern hemispheric seasonal cycles due to the inter-hemispheric mixing of air. The simulated δ(APO) underestimated the observed interannual variation in δ(APO) significantly, probably due to the interannual variation in the annual mean air-sea O2 flux. Interannual variation in δ(APO) driven by the net marine biological activities, obtained by subtracting the assumed solubility-driven component of δ(APO) from the total variation, indicated a clear evidence of influence on annual sea-to-air (air-to-sea) marine biological O2 flux during El Niño (La Niña). By analyzing the observed secular trends of δ(O2/N2) and CO2 amount fraction, global average terrestrial biospheric and oceanic CO2 uptakes for the period 2012–2019 were estimated to be (1.8 ± 0.9) and (2.8 ± 0.6) Pg a−1 (C equivalents), respectively.

Techniques for the detection and quantification of emerging contaminants

In recent years, the diverse industrial practices and human inputs widely disseminated emerging contaminants (ECs) throughout environmental matrices, which is of great concern. Even at low concentrations, ECs pose major ecological problems and threaten human health and the environment’s biota. Consequently, people’s interest and concerns on the widespread dissemination of environmentally connected ECs of great concern as developed due to their scientific understanding, technical innovation, and socioeconomic awareness. Increased detection of contaminants may occur from climatic, socioeconomic, and demographic changes and the growing sensitivity of analytical techniques. Hence, this article reviews the determination of ECs in ecological specimens, from aquatic setup (river water, marine water, and wastewater), sludge, soil, sediment, and air. Sample collection and the quality measures are summarized. The preparation of samples, including extraction and cleanup and the subsequent instrumental analysis of ECs, are all covered. Traditional and recent extraction and cleanup applications to analyze ECs in samples are reviewed here in this paper. The detection and quantification of ECs using gas chromatography (GC) and liquid chromatography (LC) linked with various detectors, particularly mass spectrometry (MS), is also summarized and explored, as are other possible techniques. This study aims to give readers a more excellent knowledge of how new and improved approaches are being developed and serve as a resource for researchers looking for the best method for detecting ECs in their studies.

Furan. Determination in workplace air with gas chromatography

Furan is colorless, highly volatile and flammable liquid with a specific ether odor. In nature it occurs in some species of wood, it is formed during burning process of wood, tobacco, fuels and also in thermal food processing. In industry furan is used as an intermediate in organic synthesis, resins solvent, during production of lacquer, drugs, stabilizers, insecticides and also in production of chemical compounds which have polymeric and coordination structure. Carcinogenic effect on animals was a base of recognition that furan is a substance which is probably also carcinogenic on humans. The aim of this study was to develop and validate a method of determining furan in workplace air. Developed determination method of furan relies on vapor absorption of this substance on coconut shell charcoal. Furan was extracted by 5% butan-1-ol solution in toluene. Obtained solution was analyzed with chromatography. The study was performed with gas chromatograph coupled with mass spectrometer (GC-MS), equipped with non-polar HP-PONA capillary column (length 50 m, diameter 0.2 mm and the film thickness of the stationary phase 0.5 µm). Developed method is linear in the concentration range of 0.05–1.0 µg/ml, which is equivalent to the range of 0.005–0.1 mg/m3 for 10-L air sample. The analytical method described in this paper makes it possible to determine furan in workplace air in the presence of comorbid substances. The method is precise, accurate and it meets the criteria for procedures for determining chemical agents listed in Standard No. PN-EN 482. The developed method of determining furan in workplace air has been recorded as an analytical procedure (see Appendix). This article discusses the problems of occupational safety and health, which are covered by health sciences and environmental engineering.