Exposure Assessment of Silver and Gold Nanoparticles Generated During the Synthesis Process in a South African Research Laboratory
During the synthesis of engineered nanomaterials (ENMs), various occupational exposures occur, leading to health consequences. To date, there is paucity of studies focused on modeling the deposition of nanoparticles emitted from ENMs synthesis processes. This study aimed to characterise and assess e...
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| Format: | Article |
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Frontiers Media S.A.
2022-05-01
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| Series: | Frontiers in Toxicology |
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| Online Access: | https://www.frontiersin.org/articles/10.3389/ftox.2022.892703/full |
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| author | Masilu D. Masekameni Charlene Andraos Il Je Yu Mary Gulumian Mary Gulumian |
| author_facet | Masilu D. Masekameni Charlene Andraos Il Je Yu Mary Gulumian Mary Gulumian |
| author_sort | Masilu D. Masekameni |
| collection | DOAJ |
| description | During the synthesis of engineered nanomaterials (ENMs), various occupational exposures occur, leading to health consequences. To date, there is paucity of studies focused on modeling the deposition of nanoparticles emitted from ENMs synthesis processes. This study aimed to characterise and assess exposure to gold (AuNPs) and silver nanoparticles (AgNPs) during a synthesis process in a research laboratory in South Africa. AuNPs and AgNPs synthesis processes were monitored for an hour in a laboratory using a Scanning Mobility Particle Sizer. The monitoring was conducted at a height of 1.2–1.5 m (m) and 1.5 m away from the hood, assuming a 30 cm (cm) breathing circumference zone. Each synthesis process was monitored thrice to generate reliable point estimates, which were used to assess exposure over 8 hours. A time-weighted average concentration was calculated and compared to the derived 8-h occupational exposure limit (OEL) for AgNPs (0.19 μg/m3) and the proposed provisional nano reference value for AuNPs (20,000 particles/cm3). The Multiple-Path Particle Dosimetry model was used to calculate the deposition and retention of both AuNPs and AgNPs. NPs emitted during the synthesis process were dominant in the nuclei (79% for AuNPs and 54% for AgNPs), followed by the Aitken (12% for AuNPs and 29% for AgNPs), with fewer particles in the accumulation mode (9.2% for AuNPs and 17% for AgNPs). AuNPs and AgNPs generated during the synthesis process were determined at 1617.3 ± 102 cm3 (0.046 μg/m3) and 2,687 cm3 ± 620 (0.077 μg/m3), respectively. For the three exposure scenarios, none exceeded the occupational exposure limit for both AuNPs (provisional) and AgNPs (OEL). Workers in the synthesis laboratory are exposed to a concentration below the recommended occupational exposure limit for silver and the proposed provisional nano reference value for gold. Although, the concentrations to which laboratory workers are exposed to are below safe levels, the assessment of the lung deposition patterns indicate a high particle lung retention which raise concerns about long term safety of workers. |
| first_indexed | 2024-04-12T17:28:26Z |
| format | Article |
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| institution | Directory Open Access Journal |
| issn | 2673-3080 |
| language | English |
| last_indexed | 2024-04-12T17:28:26Z |
| publishDate | 2022-05-01 |
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| series | Frontiers in Toxicology |
| spelling | doaj.art-bc02df5e875a4ee7b8b98dd3d75548052022-12-22T03:23:13ZengFrontiers Media S.A.Frontiers in Toxicology2673-30802022-05-01410.3389/ftox.2022.892703892703Exposure Assessment of Silver and Gold Nanoparticles Generated During the Synthesis Process in a South African Research LaboratoryMasilu D. Masekameni0Charlene Andraos1Il Je Yu2Mary Gulumian3Mary Gulumian4Occupational Health Division, School of Public Health, University of the Witwatersrand, Johannesburg, South AfricaN Toxicology and Biochemistry Department, National Institute for Occupational Health, National 7 Health Laboratory Services, Braamfontein, Johannesburg, South AfricaHCT, Majang-myeon, Icheon, KoreaHaematology and Molecular Medicine Department, University of the Witwatersrand, Johannesburg, South AfricaWater Research Group, Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South AfricaDuring the synthesis of engineered nanomaterials (ENMs), various occupational exposures occur, leading to health consequences. To date, there is paucity of studies focused on modeling the deposition of nanoparticles emitted from ENMs synthesis processes. This study aimed to characterise and assess exposure to gold (AuNPs) and silver nanoparticles (AgNPs) during a synthesis process in a research laboratory in South Africa. AuNPs and AgNPs synthesis processes were monitored for an hour in a laboratory using a Scanning Mobility Particle Sizer. The monitoring was conducted at a height of 1.2–1.5 m (m) and 1.5 m away from the hood, assuming a 30 cm (cm) breathing circumference zone. Each synthesis process was monitored thrice to generate reliable point estimates, which were used to assess exposure over 8 hours. A time-weighted average concentration was calculated and compared to the derived 8-h occupational exposure limit (OEL) for AgNPs (0.19 μg/m3) and the proposed provisional nano reference value for AuNPs (20,000 particles/cm3). The Multiple-Path Particle Dosimetry model was used to calculate the deposition and retention of both AuNPs and AgNPs. NPs emitted during the synthesis process were dominant in the nuclei (79% for AuNPs and 54% for AgNPs), followed by the Aitken (12% for AuNPs and 29% for AgNPs), with fewer particles in the accumulation mode (9.2% for AuNPs and 17% for AgNPs). AuNPs and AgNPs generated during the synthesis process were determined at 1617.3 ± 102 cm3 (0.046 μg/m3) and 2,687 cm3 ± 620 (0.077 μg/m3), respectively. For the three exposure scenarios, none exceeded the occupational exposure limit for both AuNPs (provisional) and AgNPs (OEL). Workers in the synthesis laboratory are exposed to a concentration below the recommended occupational exposure limit for silver and the proposed provisional nano reference value for gold. Although, the concentrations to which laboratory workers are exposed to are below safe levels, the assessment of the lung deposition patterns indicate a high particle lung retention which raise concerns about long term safety of workers.https://www.frontiersin.org/articles/10.3389/ftox.2022.892703/fullOELSMPSaitkenMPPD modelnanoparticles |
| spellingShingle | Masilu D. Masekameni Charlene Andraos Il Je Yu Mary Gulumian Mary Gulumian Exposure Assessment of Silver and Gold Nanoparticles Generated During the Synthesis Process in a South African Research Laboratory Frontiers in Toxicology OEL SMPS aitken MPPD model nanoparticles |
| title | Exposure Assessment of Silver and Gold Nanoparticles Generated During the Synthesis Process in a South African Research Laboratory |
| title_full | Exposure Assessment of Silver and Gold Nanoparticles Generated During the Synthesis Process in a South African Research Laboratory |
| title_fullStr | Exposure Assessment of Silver and Gold Nanoparticles Generated During the Synthesis Process in a South African Research Laboratory |
| title_full_unstemmed | Exposure Assessment of Silver and Gold Nanoparticles Generated During the Synthesis Process in a South African Research Laboratory |
| title_short | Exposure Assessment of Silver and Gold Nanoparticles Generated During the Synthesis Process in a South African Research Laboratory |
| title_sort | exposure assessment of silver and gold nanoparticles generated during the synthesis process in a south african research laboratory |
| topic | OEL SMPS aitken MPPD model nanoparticles |
| url | https://www.frontiersin.org/articles/10.3389/ftox.2022.892703/full |
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