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1.
Chemosphere ; 349: 140854, 2024 Feb.
Article En | MEDLINE | ID: mdl-38043621

Scientific interest in SOA influence on indoor air quality increases since last 20 years. It is well known, that particles of nano-sized diameter pose a threat for human health causing, among others: eye, upper airway irritation, inflammatory response in cells, worsening asthma, hypertension, diabetes, and central nervous dysfunction. Terpenes are reactive VOCs, commonly emitted in indoor air and considered to be SOA precursors by oxidation reactions. The aim of this study was to investigate the relative humidity influence on i) formation of limonene ozonolysis products and ii) SOA formation process - especially the first steps of it. We managed to determine 4 uncommon limonene ozonolysis products (m/z: 43, 83, 99 and 110) appearing in the PTR-TOF-MS mass spectra with the same frequency as well-known formaldehyde, acetone, acetic acid and formic acid. We also detected m/z 75 and m/z 115 formed under dry conditions and m/z 111 and m/z 125 formed under humid conditions. Detected masses formula is proposed with probability >70 % and the probability is derived from the deviation of the exact mass to the measured one and the isotope distribution. SMPS data analysis allowed us to conclude that RH around 40% increases particle mass concentration, regardless initial limonene concentration. Unfortunately, conclusions about RH influence on particle number concentration are inconsistent. Under low initial terpene concentration, RH around 40% decreases particle number concentration. However, for high initial limonene concentration, RH around 40% caused increase in particle number concentration. Obtained results allowed to conclude, that i) RH influences both particle number and particle mass concentration, ii) initial substrate concentration influences SOA formation altering the RH effect, iii) comparison of results and drawing conclusions is difficult due to different experimental protocols in the literature and due to the number of factors influencing SOA formation initiated by terpene oxidation.


Air Pollutants , Air Pollution, Indoor , Ozone , Humans , Limonene/analysis , Cyclohexenes , Air Pollution, Indoor/analysis , Air Pollutants/analysis , Ozone/analysis , Aerosols/analysis , Terpenes
2.
Sci Rep ; 13(1): 7141, 2023 05 02.
Article En | MEDLINE | ID: mdl-37130866

Microshoot cultures of the North American endemic Salvia apiana were established for the first time and evaluated for essential oil production. Stationary cultures, grown on Schenk-Hildebrandt (SH) medium, supplemented with 0.22 mg/L thidiazuron (TDZ), 2.0 mg/L 6-benzylaminopurine and 3.0% (w/v) sucrose, accumulated 1.27% (v/m dry weight) essential oil, consisting mostly of 1,8-cineole, ß-pinene, α-pinene, ß-myrcene and camphor. The microshoots were adapted to agitated culture, showing biomass yields up to ca. 19 g/L. Scale-up studies demonstrated that S. spiana microshoots grow well in temporary immersion systems (TIS). In the RITA bioreactor, up to 19.27 g/L dry biomass was obtained, containing 1.1% oil with up to ca. 42% cineole content. The other systems employed, i.e. Plantform (TIS) and a custom made spray bioreactor (SGB), yielded ca. 18 and 19 g/L dry weight, respectively. The essential oil content of Plantform and SGB-grown microshoots was comparable to RITA bioreactor, however, the content of cineole was substantially higher (ca. 55%). Oil samples isolated from in vitro material proved to be active in acetylcholinesterase (up to 60.0% inhibition recorded for Plantform-grown microshoots), as well as hyaluronidase and tyrosinase-inhibitory assays (up to 45.8 and 64.5% inhibition observed in the case of the SGB culture).


Oils, Volatile , Salvia , Oils, Volatile/pharmacology , Oils, Volatile/chemistry , Salvia/chemistry , Eucalyptol , Acetylcholinesterase , Bioreactors
3.
Article En | MEDLINE | ID: mdl-36497918

Studies show that forests are one of the main recreational destinations. This can be explained by their beneficial effects on the health of their visitors, which can be attributed to compounds from the terpene group. The aim of this research was to determine the chemical composition of air in the interiors of Nemoral Scots pine forests and submountainous beech forests, with the determination of compounds of the terpene group. Samples of organic compounds present in the air were collected with the use of Tenax TA sorbent tubes. The process of separation, identification, and determination of the extracted organic compounds was carried out with the use of the gas chromatography technique integrated with a flame ionization detector. Additional identification of the extracted compounds was carried out with the use of GC coupled with mass spectrometry. The most abundant group of compounds was the aliphatic hydrocarbons, both saturated (linear and branched) and unsaturated (terpenes). Carbonyl compounds were also found in the collected samples, but they constituted no more than 10% of all compounds present on the chromatograms. The concentrations of terpenes and terpenoids in the forest atmosphere varied from 10 to 74 µg·m-3, representing on average 33% of the total volatile organic compounds.


Fagus , Volatile Organic Compounds , Forests , Volatile Organic Compounds/analysis , Atmosphere/analysis , Flame Ionization , Terpenes/analysis , Terpenes/chemistry
4.
Biomed Pharmacother ; 153: 113349, 2022 Sep.
Article En | MEDLINE | ID: mdl-35779419

In previous work, we tested the immunomodulatory effect of Nigella sativa (NS) fatty oil. Our results demonstrated that unrefined, obtained by cold pressing black cumin seed oil inhibited lymphocytes' proliferation and induced their apoptosis in a dose-dependent manner. In this study, we examined the immunomodulatory properties of essential oil (EO) obtained from the NS seeds by hydrodistillation and its two main constituents: thymoquinone (TQ) and p-cymene. We analyzed the proliferation, activation phenotype, and apoptosis rates of human T lymphocytes stimulated with an immobilized monoclonal anti-CD3 antibody in the presence of serial ethanol dilutions of tested oil or serial distilled water dilutions of tested compounds with flow cytometry. Our results showed that NSEO significantly inhibited the proliferation of CD4+ and CD8+ T lymphocytes, induced cell death in a dose-dependent manner, and reduced the expression of CD28 and CD25 antigens essential for lymphocyte activation. TQ inhibited the proliferation of T lymphocytes and induced cell death, particularly in high concentrations. Meanwhile, p-cymene did not influence lymphocyte proliferation. However, its high concentration induced cell necrosis. These results show that the essential oil from Nigella sativa has powerful immunomodulatory properties, which, at least partially, are related to the TQ component.


Nigella sativa , Oils, Volatile , Apoptosis , Benzoquinones/pharmacology , Carum , Cell Proliferation , Humans , Oils, Volatile/pharmacology , Plant Oils , T-Lymphocytes
5.
Molecules ; 27(12)2022 Jun 14.
Article En | MEDLINE | ID: mdl-35744939

In this short communication we characterize the emission of volatile organic compounds (VOCs) from fused filament fabrication (FFF) 3D printing using four polymer materials, namely polyethylene terephthalate glycol-modified (PETG), acrylonitrile styrene acrylate (ASA), Nylon, and acrylonitrile butadiene styrene (ABS). Detailed emission profiles are obtained during thermal degradation of the polymers as a function of temperature and also in real-time during 3D printing. Direct quantitative measurement was performed using proton transfer reaction time-of-flight mass spectrometry (PTR-ToF-MS). Qualitative determination of the volatiles emitted from the printed elements at various temperatures was accomplished using gas chromatography-mass spectrometry (GC-MS). The emission rates of VOCs differ significantly between the different polymer filaments, with the emission from Nylon and PETG more than an order of magnitude lower than that of ABS.


Acrylonitrile , Air Pollution, Indoor , Volatile Organic Compounds , Air Pollution, Indoor/analysis , Butadienes/chemistry , Nylons , Particulate Matter/analysis , Polymers , Printing, Three-Dimensional , Styrene/analysis , Thiogalactosides , Volatile Organic Compounds/analysis
6.
Sci Total Environ ; 843: 156948, 2022 Oct 15.
Article En | MEDLINE | ID: mdl-35753459

Recent studies proves that indoor air chemistry differs in many aspects from atmospheric one. People send up to 90 % of their life indoors being exposed to pollutants present in gas, particle and solid phase. Particle phase indoor is composed of particles emitted from various sources, among which there is an indoor source - secondary chemical reactions leading to formation of secondary organic aerosol (SOA). Lately, researchers' attentions turned towards the ultrafine particles, for there are still a lot of gaps in knowledge concerning this field of study, while there is evidence of negative influence of ultrafine particles on human health. Presented review sums up current knowledge about secondary particle formation in indoor environment and development of analytical techniques applied to study those processes. The biggest concern today is studying ROS, for their lifetime in indoor air is very short due to reactions at the very beginning of terpene oxidation process. Another interesting aspect that is recently discovered is monoterpene autooxidation process that leads to HOMs formation that in turn can influence SOA formation yield. A complex studies covering gas phase and particle phase characterization, but also toxicological studies are crucial to fully understand indoor air chemistry leading to ultrafine particle formation.


Air Pollutants , Air Pollution, Indoor , Ozone , Aerosols/analysis , Air Pollutants/analysis , Air Pollution, Indoor/analysis , Humans , Ozone/analysis , Particulate Matter
7.
Sci Total Environ ; 805: 150181, 2022 Jan 20.
Article En | MEDLINE | ID: mdl-34537709

Establishing the emission profile of volatile organic compounds generated during fused deposition modeling 3D printing using polymer filaments is important in terms of both understanding the processes taking place during thermal degradation of thermoplastics, and assessing the user's exposure to potentially harmful volatiles. However, obtaining detailed, real-time qualitative and quantitative results poses a challenge. In this paper solid-phase microextraction-gas chromatography-time-of-flight mass spectrometry and proton transfer reaction time-of-flight mass spectrometry were used to identify and monitor the emission of volatiles during thermal degradation of polylactide filaments and during 3D printing. Filaments of two different grades and three colours were used. It was possible to obtain detailed, time- and temperature-resolved emission profiles of the main products of thermal decomposition of lactide and polylactide 3D printing filaments at concentration levels of a few µg/g. This revealed different temperature-dependent emission characteristics of particular volatiles, such as, among others, lactide, acetaldehyde, acetic acid, and 2-butanone between various polylactide 3D printing filaments. This approach can be used to monitor the emission associated with printing with various other types of polymer 3D printing materials.


Volatile Organic Compounds , Gas Chromatography-Mass Spectrometry , Polyesters , Printing, Three-Dimensional , Volatile Organic Compounds/analysis
8.
Environ Sci Pollut Res Int ; 28(42): 59214-59232, 2021 Nov.
Article En | MEDLINE | ID: mdl-32661962

Due to excessive application of essential oils and scented products in spa salons during aromatherapy and massage sessions, the elevated concentration of total volatile organic compounds (TVOCs), particularly terpenes, which are known as secondary organic aerosol (SOA) precursors, is expected there. This study was aimed at determination of VOCs with a particular regard to terpenes in air samples collected in selected spa salons located in Northern Poland. Active air sampling was conducted before and after treatments. Samples were analyzed with the use of thermal desorption gas chromatography coupled with flame-ionization detector (TD-GC-FID) and mass spectrometer (TD-GC-MS). Obtained results allowed to characterize chemical composition of indoor air of spa salons and also to relate the dependence between applied essential oil and indoor air chemical composition. It has been proved that (i) spa salons are characterized by TVOC concentrations exceeding recommended values of 300-400 µg m-3 in most of examined cases, reaching up to several thousand of micrograms per cubic meter, (ii) TVOC concentration is strictly related to salon characteristics and carried out treatments, (iii) terpenes constitute a significant part of TVOCs present in spa indoor air, from 22 up to 86%, (iv) most commonly investigated terpenes in the literature (D-limonene, α-pinene, camphene, and linalool) were also determined at the highest concentration levels in this study and (v) VOC chemical composition is strictly dependent on the type of applied essential oils. On the basis of obtained results, it may be stated that extensive application of essential oils rich in terpenes can significantly alter indoor air chemistry of spa salons, thereby influencing health and well-being of employees working there. Graphical abstract.


Air Pollutants , Air Pollution, Indoor , Volatile Organic Compounds , Air Pollution, Indoor/analysis , Environmental Monitoring , Gas Chromatography-Mass Spectrometry , Poland , Terpenes/analysis , Volatile Organic Compounds/analysis
9.
Sensors (Basel) ; 20(19)2020 Sep 27.
Article En | MEDLINE | ID: mdl-32992544

We describe a concept study in which the changes of concentration of benzene, toluene, ethylbenzene, and xylene (BTEX) compounds and styrene within a 3D printer enclosure during printing with different acrylonitrile butadiene styrene (ABS) filaments were monitored in real-time using a proton transfer reaction mass spectrometer and an electronic nose. The quantitative data on the concentration of the BTEX compounds, in particular the concentration of carcinogenic benzene, were then used as reference values for assessing the applicability of an array of low-cost electrochemical sensors in monitoring the exposure of the users of consumer-grade fused deposition modelling 3D printers to potentially harmful volatiles. Using multivariate statistical analysis and machine learning, it was possible to determine whether a set threshold limit value for the concentration of BTEX was exceeded with a 0.96 classification accuracy and within a timeframe of 5 min based on the responses of the chemical sensors.

10.
Molecules ; 25(9)2020 May 08.
Article En | MEDLINE | ID: mdl-32397186

Terpenes are VOCs of particular importance, since they are emitted from a wide range of indoor sources and are considered to be precursors of Secondary Organic Aerosol (SOA) formation. It has been proven that SOA particles, especially nanosized ones, pose a threat to human health. In this research, experiments with the application of an environmental chamber and real-time measurement techniques were carried out to investigate in a complimentary way the formation of monoterpene oxidation products and nanosized SOA particles initiated by monoterpene ozonolysis. Proton-Transfer-Reaction Mass Spectrometry with a Time-Of-Flight analyzer (PTR-TOF-MS) and a Scanning Mobility Particle Sizer (SMPS) were applied to determine in real time the dynamism of the formation of the corresponding terpene ozonolysis products and submicron SOA particles. Results proved that firstly, oxidation products were formed, and then, they underwent nucleation and condensation, forming particles whose diameters grew with time. The oxidation products formed were different depending on the type of terpenes applied. The comparison of the results obtained during the experiments with gaseous standard mixtures and real samples commonly present and used in indoor air revealed that the diversified chemical composition of the emission source had implications for both the particle formation initiated by the oxidation of essential oil components and the chemical reactions occurring via the oxidation process. With the instrumentation utilized, the concentration changes at the level of a few ppbv could be monitored.


Air Pollution, Indoor/analysis , Mass Spectrometry , Models, Chemical , Protons , Aerosols , Terpenes/analysis , Terpenes/chemistry
12.
Fitoterapia ; 139: 104402, 2019 Nov.
Article En | MEDLINE | ID: mdl-31672661

Rhododendron tomentosum (Ledum palustre) is an aromatic plant traditionally used for alleviating rheumatic complaints which makes it a potential candidate for a natural drug in rheumatoid arthritis (RA) treatment. However, the effects of plants' volatiles on apoptosis of synovial fibroblasts and infiltrating leucocytes of RA synovia, have not been reported. Volatile fraction of R. tomentosum is chemically variable and chemotypes of the plants need to be defined if the oil is to be used for therapeutic purposes. In the presented work, cluster analysis of literature data enabled to define 10 chemotypes of the plant. The volatile fractions of known composition were then tested for bioactivity using a RA-specific in vitro models. Essential oils of two wild types (γ-terpineol and palustrol/ledol type) and one in vitro chemotype (ledene oxide type) were obtained by hydrodistillation and their bioactivity was tested in two in vitro models: I - peripheral blood lymphocytes of healthy volunteers and II - synoviocytes and immune cells isolated from synovia of RA patients. The influence of oils on blood lymphocytes' proliferation and apoptosis rates of synovia-derived cells was determined by flow cytometry. Dose-dependent inhibitory effect of the serial dilutions of R. tomentosum oils on proliferation rates of blood lymphocytes was found. At 1:400 dilutions, all the tested oils increased the number of necrotic cells in synovial fibroblasts from RA synovia. Additionally, increased proportions of late apoptotic cells were observed in leucocyte populations subjected to oils at 1:400 dilution.


Apoptosis , Ledum/chemistry , Lymphocytes/drug effects , Oils, Volatile/pharmacology , Plant Oils/pharmacology , Synoviocytes/drug effects , Adult , Arthritis, Rheumatoid , Cell Proliferation/drug effects , Female , Finland , Humans , Middle Aged , Molecular Structure , Plant Shoots/chemistry , Poland
13.
Anal Chim Acta ; 1084: 33-42, 2019 Nov 25.
Article En | MEDLINE | ID: mdl-31519232

In the present study a novel analytical procedure for the determination of polybrominated diphenyl ethers in dust samples was developed. The main aim of the research was the selection of the optimum conditions of the matrix solid-phase dispersion before the final determination of polybrominated diphenyl ethers in dust samples. In order to assess the best usefulness of this technique, a favourable ratio of sample amount to the mass of dispersing sorbent, as well as the type of this sorbent used has been tested. The type of sorbent responsible for additional purification (clean-up sorbent) of the extract during matrix solid-phase dispersion was also selected. Gas chromatography coupled with mass spectrometry will be used at the final determination step. Preliminary results indicate that the use of matrix solid-phase dispersion can be a promising alternative to other time-consuming and multi-stage analytical procedures. The proposed method provided satisfactory recoveries (76-119%) and limits of detection: 2.1-4.4 pg µL-1 for tri-heptaBDE in linear range of 5-100 pg µL-1; 480 pg µL-1 for decaBDE in linear range of 500-2000 pg µL-1 from only 0.05 g of a dust sample. Finally, the method was applied to study the content of selected polybrominated diphenyl ethers in real dust samples. Some polybrominated diphenyl ether congeners reached up to (16.3 ±â€¯3.0)·102 ng g-1.

15.
Environ Sci Pollut Res Int ; 25(3): 2065-2082, 2018 Jan.
Article En | MEDLINE | ID: mdl-29192399

According to literature data, some of the main factors which significantly affect the quality of the indoor environment in residential households or apartments are human activities such as cooking, smoking, cleaning, and indoor exercising. The paper presents a literature overview related to air quality in everyday use spaces dedicated to specific purposes which are integral parts of residential buildings, such as kitchens, basements, and individual garages. Some aspects of air quality in large-scale car parks, as a specific type of indoor environment, are also discussed. All those areas are characterized by relatively short time use. On the other hand, high and very high concentration levels of xenobiotics can be observed, resulting in higher exposure risk. The main compounds or group of chemical compounds are presented and discussed. The main factors influencing the type and amount of chemical pollutants present in the air of such areas are indicated.


Air Pollution, Indoor/analysis , Air Pollution , Cooking , Housing , Humans
16.
Environ Sci Pollut Res Int ; 24(12): 11166-11176, 2017 Apr.
Article En | MEDLINE | ID: mdl-28236201

Indoor air quality has been the object of interest for scientists and specialists from the fields of science such as chemistry, medicine and ventilation system design. This results from a considerable number of potential factors, which may influence the quality of the broadly understood indoor air in a negative way. Poor quality of indoor air in various types of public utility buildings may significantly affect an increase in the incidence of various types of civilisation diseases. This paper presents information about a broad spectrum of chemical compounds that were identified and determined in the indoor environment of various types of public utility rooms such as churches, museums, libraries, temples and hospitals. An analysis of literature data allowed for identification of the most important transport paths of chemical compounds that significantly influence the quality of the indoor environment and thus the comfort of living and the health of persons staying in it.


Air Pollution, Indoor/analysis , Public Facilities , Ventilation , Environment , Humans
17.
Sci Total Environ ; 573: 767-777, 2016 Dec 15.
Article En | MEDLINE | ID: mdl-27591527

The paper describes the characteristics of a two-level underground car park and three individual garages attached to residential buildings, differing by the resident utilization habits, located in North Poland (Tri-City agglomeration area). The strategy of collecting the analyte samples from air in mentioned enclosed areas, concerning the determination of benzene, toluene, ethylbenzene, o-xylene and p,m-xylenes (BTEX) concentrations was performed using passive sampling technique - Radiello® diffusive passive samplers with graphitised charcoal cartridge as a sorption medium. The stage of liberation and final determination of collected analytes was conducted with the use of thermal desorption-gas chromatography-flame ionisation detector (TD-GC-FID) system. As a result of the performed measurements in two-level underground car park, it was observed that the time-weighted average concentrations of BTEX in air were as follows: Level-1 - benzene - 5.2±1.1µg/m3, toluene - 12.3±2.4µg/m3, ethylbenzene 2.85±0.80µg/m3, o-xylene - 4.6±1.4µg/m3, p, m-xylenes - 8.8±2,4µg/m3; Level-2 - benzene - 5.2±1.1µg/m3, toluene - 12.9±3.6µg/m3, ethylbenzene - 2.73±0.79µg/m3, o-xylene - 4.2±1.1µg/m3, p, m-xylenes - 8.5±2.3µg/m3. As for residential garages, the time-weighted average concentrations of BTEX in air were in the following ranges: from 5.9 to 53µg/m3 (benzene), from 7.1 to 195µg/m3 (toluene), from 3.0 to 39µg/m3 (ethylbenzene), from 5.6 to 44µg/m3 (o-xylene) and from 6.3 to 99µg/m3 (p,m-xylenes). Also, BTEX concentration ratios such as: tol/benz ratio and (m, p)-xyl/et.benz coefficient, were calculated based on the obtained results to assess the "freshness" of air mass and the influence exerted by vehicle movement on the concentration of BTEX in air in studied enclosed areas.


Air Pollutants/analysis , Air Pollution, Indoor/analysis , Hydrocarbons, Aromatic/analysis , Vehicle Emissions/analysis , Environmental Monitoring , Poland
18.
Environ Res ; 147: 513-24, 2016 May.
Article En | MEDLINE | ID: mdl-26990845

The major goal of the present study is to compare the air quality of two urban locations situated in Northern Poland - the spa City of Sopot and the medium-industrialized city of Tczew using chemometric methods. As a criterion for the assessment of atmospheric air quality, measurements of benzene, toluene, ethylbenzene and total xylenes were used (collected from atmospheric air using diffusion-type passive samplers) as well as measurements of inorganic compounds - CO, NO2 and SO2, which were subject to routine control and determined by means of automatic analysers. Studies related to determination of defined chemical compounds in the urban air in the monitored area were performed from January 2013 to December 2014. By interpreting the results obtained and using basic multivariate statistical tools (cluster analysis and principal components analysis), major sources of emissions of determined pollutants in the air in urbanized areas were defined. The study also shows the potential influence of the sea breeze on concentrations of chemical compounds in the atmospheric air in the spa city of Sopot.


Air Pollutants/analysis , Benzene Derivatives/analysis , Cities/statistics & numerical data , Oxides/analysis , Poland
19.
Anal Bioanal Chem ; 407(22): 6879-84, 2015 Sep.
Article En | MEDLINE | ID: mdl-26116240

The paper presents the construction and metrological characteristics of the home-made in situ passive flux sampler, an analytical tool representing small-scale emission chambers working in situ and passively sampling analytes from the gaseous phase. The sorption element was a cylindrical container made of stainless steel net, packed with a carbon sorbent bed-graphitized charcoal, Carbograph 4 (35/50 mesh). The recommended working/exposure time of the constructed passive device was determined by carrying out model tests in the laboratory. In addition, a preliminary study was conducted to determine the rate of the emission flux of selected monoterpenes released from the surface of wood-based indoor materials (laminated chipboard) used in residential areas.

20.
Sci Total Environ ; 530-531: 290-296, 2015 Oct 15.
Article En | MEDLINE | ID: mdl-26047863

The article presents findings on the emissions of selected monoaromatic hydrocarbons from children's toys placed in chocolate food products. The emission test system involved the application of a new type of microscale stationary emission chamber, µ-CTE™ 250. In order to determine the type of the applied polymer in the manufacture of the tested toys, Fourier transform infrared spectroscopy and thermogravimetric analysis coupled with differential scanning calorimetry were used. It was found that the tested toy components or the whole toys (figurines) are made of two main types of polymers: polyamide and acrylonitrile-butadiene-styrene copolymer. Total number of studied small polymeric toys was 52. The average emissions of selected monoaromatic hydrocarbons from studied toys made of polyamide were as follows: benzene: 0.45 ± 0.33 ng/g; toluene: 3.3 ± 2.6 ng/g; ethylbenzene: 1.4 ± 1.4 ng/g; p,m-xylene: 2.5 ± 4.5 ng/g; and styrene: 8.2 ± 9.9 ng/g. In the case of studied toys made of acrylonitrile-butadiene-styrene copolymer the average emissions of benzene, toluene, ethylbeznene, p,m-xylene and styrene were: 0.31 ± 0.29 ng/g; 2.5 ± 1.4 ng/g; 4.6 ± 8.9 ng/g; 1.4 ± 1.1 ng/g; and 36 ± 44 ng/g, respectively.


Cacao , Hazardous Substances/analysis , Hydrocarbons/analysis , Play and Playthings , Air Pollutants/analysis , Food Contamination/analysis , Food Contamination/statistics & numerical data
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