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Distribution patterns of 10 phthalic acid diesters (PAEs) and four cyclic volatile methylsiloxanes (cVMSs) were investigated in fine particulate matter (PM 0.1 and PM 0.5 ) collected from Bac Ninh, an industrial province in Vietnam during September-October in 2021. Total concentrations of PAEs found in PM 0.1 and PM 0.5 were in the ranges of 1.76-372 (median: 34.0 ng/m 3 ) and 2.23-895 ng/m 3 (median: 15.4 ng/m 3 ), respectively. Among PAEs, di-n-butyl phthalate (DBP) was the most abundant compound found in PM 0.1 , whereas, di-2-(ethyl)hexyl phthalate (DEHP) was measured at the highest concentration in PM 0.5 . Total concentrations of cVMSs measured in PM 0.1 and PM 0.5 were in the ranges of method quantification limit (MQL)-203 (median: 2.10 ng/m 3 ) and MQL-537 ng/m 3 (median: 0.389 ng/m 3 ), respectively. Among cVMSs, decamethylcyclopentasiloxane (D5) was found at the highest concentration in both PM 0.1 and PM 0.5 fractions of particulate matter. The concentration ratios between PAEs and cVMSs in PM 0.1 /PM 0.5 were greater than 1 (except di-n-octyl phthalate: DnOP), suggesting that these chemicals tend to sorb to PM 0.1 more preferentially than PM 0.5 . Among sampling locations, high concentrations of PAEs and cVMSs were found at traffic intersections (Que Vo district) and a craft village (Tu Son city). Relatively stronger correlations existed between cVMSs pairs in PM 0.1 and PM 0.5 (correlation coefficient: 0.73-1) than those of PAEs (-0.83-0.90). The human exposure doses to PAEs and cVMSs through inhalation of particulate matter were estimated based on the measured concentrations in PM 0.1 and PM 0.5 fractions. The estimated exposure doses of PAEs and cVMSs for infants (7.1 ng/kg-bw/d and 2.5 ng/kg-bw/d) were higher than those for adults (2.6 ng/kg-bw/d and 0.9 ng/kg-bw/d)., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper:, (Copyright © 2023 Elsevier Inc. All rights reserved.)

Pollution status and distribution characteristics of ten typical phthalic acid esters (PAEs) were investigated in 36 sediment samples collected from three rivers in Northern Vietnam from June to October 2020. The total concentrations of PAEs in sediment samples collected from the To Lich River (n = 9), the Nhue River (n = 12), and the Day River (n = 15) were in ranges of 11,000-125,000 ng/g-dwt (mean/median: 50,000/42,200 ng/g-dwt), 2140-89,900 ng/g-dwt (mean/median: 29,300/20,700 ng/g-dwt), and 1140-43,100 ng/g-dwt (mean/median: 13,800/10,400 ng/g-dwt), respectively. Among ten PAEs studied, di-(2-ethylhexyl) phthalate (DEHP) was found at the highest levels in all samples meanwhile dimethyl phthalate (DMP), diethyl phthalate (DEP), and dipropyl phthalate (DPP) were detected at low frequency and concentration. Significant correlations have existed between the median-chain (C 4 -C 7 ) PAE pairs in sediment samples. Due to the high accumulation in the sediments, the median-chain PAEs had a higher ecological risk than the short-chain (C 1 -C 3 ) PAEs. These contaminants may present a longstanding influence on organisms and ecosystems., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Contamination levels and distribution patterns of ten typical phthalic acid esters (PAEs) were investigated in various types of water samples collected from Hanoi metropolitan area in Vietnam. Concentrations of 10 PAEs in bottled water, tap water, lake water, and wastewater samples were measured in the ranges of 1640-15,700 ng/L (mean/median: 6400/5820 ng/L), 2100-18,000 ng/L (mean/median: 11,200/9270 ng/L), 19,600-127,000 ng/L (mean/median: 51,800/49,300 ng/L), and 20,700-405,000 ng/L (mean/median: 121,000/115,000 ng/L), respectively. Among PAEs, di-(2-ethylhexyl) phthalate (DEHP) accounted for a major proportion of total concentrations (45%) in wastewater, followed by diisobutyl phthalate (DiBP, 10.3%), and dibutyl phthalate (DBP, 9.53%). Concentrations of PAEs in wastewater decreased significantly with distance from the wastewater treatment plants (WWTPs). Concentrations of PAEs in surface water samples did not vary greatly between locations. PAEs were found in bottled water in the following order: DBP (22.4%), DiBP (22.3%), benzylbutyl phthalate (BzBP, 20.1%), and DEHP (15.5%). The estimated mean exposure doses of 10 PAEs through consumption of drinking water for adults and children in Vietnam were 254 and 256 ng/kg-bw/day, respectively. Capsule: Highest concentrations of PAEs were measured in wastewater, followed by lake water, tap water, and bottled water., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)