centre dust and the exposure risk for young

Overview

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Key numbers

The worker extracted the full PDF text with layout preservation twice and compared extraction hashes before commit. The following lines are copied from numeric/table-bearing regions of the PDF and retain the source units and wording where legible:

• Received 17 January 2023 chemicals, such as tetrabromobisphenol-A (TBBPA) and hexabromocyclododecane (HBCDD), from indoor
• TBBPA was detected in all samples with a median concentration of 35 ng g
  1 (range, 14e5017.7 ng g
  1).
• The median level of HBCDD was lower than the quantitation limit (LOQ) with <LOQ to 86.6 ng g
  1 of dust
• Electronic devices children via these two pathways were ranged 0.7  10
  6 e 2.7  10
  4 for TBBPA and 1.8  10
  5 e
• • Corresponding author. Graduate Program in Environmental and Water Re- humans, as most people spend more than 70% of their time indoors
• hexabromocyclododecane (HBCDD) are BFRs that are widely used 2. Materials and methods
• (3,4,6,7). TBBPA is primarily applied as a reactive flame retardant to HBCDD; and 13C12-TBBPA (each with purity 98%). The d18-g-
• onto a solid-phase extraction cartridge packed with 4 g of pre- either 0.05 or 0.2 g day
  1 (17) to consider both median and high
• Chromatographic separation of TBBPA and HBCDD isomers (a-, b-, and is equal to 33% (8/24 h) (16).
• The certified reference material SRM 2585 (n ¼ 5) was used to human exposure. All contaminant concentrations below the LOQ
• (80e123%), with relative standard deviation values below 15%. The ShapiroeWilk test was used to check the normality of the data.
• spiked dust samples were 81e118%, with a mean value of 92 ± 13%, and the target substance concentrations in the child daycare centre
• and 93e117%, with a mean value of 105 ± 7%, respectively. dust. A p-value less than 0.05 was considered to indicate statistical
• takes through dust ingestion were calculated using the following Table 1 summarises the concentrations of TBBPA and HBCDD in
• detected in all samples analysed (100%, n ¼ 20), whereas HBCDD
• EDIIngestion ¼ (Cdust* EF* IR)/BW (1) was detected in 35% of the dust samples. The median concentra-
• to be 33% of their time (8/24 h) (16). IR is the daily ingestion rate (g (5017.7 ng g
  1). In this child daycare centre, the classroom is a large
• day
  1), which assumes 100% absorption of contaminants from dust hall divided into three smaller classrooms by boundary partitions.
• assuming 100%, and the risk assessment may be overestimated. We foam mattresses. Additionally, two smaller rooms on one side had
• consider that 100% of our study indicates a worst-case health risk the doors open all day. One room was used to store several elec-
• Summary of concentrations (ng g
  1) of TBBPA and HBCDD in indoor dust from selected countries, reported concentration of this substance as median (min.e max.).
• HBCDD (27e62%), followed by a-HBCDD (19e57%) and b-HBCDD
• report (4) found a median concentration of TBBPA in kindergarten significant source of HBCDD contamination in the child daycare
• the contrary, we found that our median result of TBBPA was 250 (17) and >500 times lower than the concentration (412.1 ng g
  1) in
• collected in preschools by previous studies showed median HBCDD contaminate with various harmful substances (35). If TBBPA is used
• and area of each sampled surface floor are described in Table S1. The
• were evaluated based on the median and 95th percentile concen-
• (18). This may be because the median concentration of HBCDD in
• Fig. 2. Electronic density and TBBPA and HBCDD concentration for each child daycare tively, under the median exposure scenario. The total daily intake
• HBCDD hexabromocyclododecane (20) S. Waiyarat, S.K. Boontanon, N. Boontanon, S. Fujii, S. Harrad, D.S. Drage, M.A.-
• (3) M.A.-E. Abdallah, M. Bressi, T. Oluseyi, S. Harrad, Hexabromocyclododecane flame retardants from indoor dust and the influence of topically applied
• j.scitotenv.2015.01.034. diastereomer patterns of hexabromocyclododecanes in indoor dust, Environ.
• (9) Y. Wu, Y. Li, D. Kang, J. Wang, Y. Zhang, D. Du, B. Pan, Z. Lin, C. Huang, Q. Dong, clododecanes in flame-proofed polystyrene materials, Chemosphere 80
• (38) US-NRC (US-National Research Council), Hexabromocyclododecane.Toxico- (39) Committee on the toxicity of UK (COT), Addendum to the 2015 COT Statement

Methods (brief)

• hexabromocyclododecane in Thai child daycare
• ‘Concentrations of Tetrabromobisphenol-A and hexabromocyclododecane in Thai child daycare centre dust and
• hexabromocyclododecane in Thai child daycare centre dust and the
• Received 17 January 2023 chemicals, such as tetrabromobisphenol-A (TBBPA) and hexabromocyclododecane (HBCDD), from indoor
• Thailand, where no such study has yet been reported. Therefore, in this study, we collected dust samples
• TBBPA was detected in all samples with a median concentration of 35 ng g
  1 (range, 14e5017.7 ng g
  1).
• The median level of HBCDD was lower than the quantitation limit (LOQ) with <LOQ to 86.6 ng g
  1 of dust
• sample. The electronic density score was calculated from the number of electronic appliances divided by
• Hexabromocyclododecane each sampled surface floor area that revealed an abundance of TBBPA in the dust in rooms with many
• hexabromocyclododecane (HBCDD) are BFRs that are widely used 2. Materials and methods
• When applied additively, BFRs do not covalently bind to the original performance liquid chromatography (HPLC) quality from Merck.
• 2.2. Sample collection
• Detailed sampling, sample extraction, and clean-up procedures
• were based on previous studies (3,18,22,23). Briefly, dust samples
• centre, one sample of dust was collected from a classroom where
• the floor was vacuumed for 4 min. The dust samples were collected
• dust samples were transported to the laboratory in a cooler with
• ice. In the laboratory, each sample was passed through a sieve

Implications

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Verification notes

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Update history

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