Contaminant occurrence, mobility and ecological risk assessment of phthalate esters in the sediment-water system of the Hangzhou Bay was written by Wang, Liu-Yong;Gu, Yan-Yu;Zhang, Ze-Ming;Sun, Ai-Li;Shi, Xi-Zhi;Chen, Jiong;Lu, Yin. And the article was included in Science of the Total Environment in 2021.Name: Dicyclohexyl phthalate This article mentions the following:
The pollution characteristics, spatiotemporal variation, sediment-water partitioning, and potential ecol. risk assessment of phthalate esters (PAEs) in the sediment-seawater system of the Hangzhou Bay (HZB) in summer and autumn were researched. The sum of the concentrations of the 10 PAEs in seawater ranges from 7305 ng/L to 22,861 ng/L in summer and from 8100 ng/L to 33,329 ng/L in autumn, with mean values of 15,567 ± 4390 and 17,884 ± 6850 ng/L, resp. The Σ16PAEs in the sediments are between 118 and 5888μg/kg and 145 and 4746μg/kg in summer and autumn, resp. The level of PAEs in seawater varies with the seasons, but it is relatively stable in the sediments. Di(2-ethylhexyl) phthalate (DEHP), di-Bu phthalate (DnBP), and diisobutyl phthalate (DiBP) are the predominant PAE congeners in the HZB. The DnBP and DiBP concentrations in seawater are greater than the DEHP concentration, which is the opposite in the sediments. The sediment-seawater equilibrium distribution study indicates that the PAEs with medium mol. weights, such as DiBP, Bu benzyl phthalate, and DnBP, are near dynamic equilibrium in the sediment-seawater system; PAEs with high mol. weights (e.g., di-n-octyl phthalate and DEHP) tend to transfer from water to the sediments; and PAEs with low mol. weights (e.g., di-Me phthalate, di-Et phthalate, and diamyl phthalate) tend to spread to seawater. The risk assessment results in seawater indicate that DEHP and DiBP might pose high potential risks to sensitive organisms, and DnBP might exhibit medium ecol. risks. In the sediment, DiBP might display a high potential risk to fish, and the potential risk of DEHP is high in several sites. In the experiment, the researchers used many compounds, for example, Dicyclohexyl phthalate (cas: 84-61-7Name: Dicyclohexyl phthalate).
Dicyclohexyl phthalate (cas: 84-61-7) belongs to esters. Carboxylic acid esters of low molecular weight are colourless, volatile liquids with pleasant odours, slightly soluble in water. Esters contain a carbonyl center, which gives rise to 120° C–C–O and O–C–O angles. Unlike amides, esters are structurally flexible functional groups because rotation about the C–O–C bonds has a low barrier. Their flexibility and low polarity is manifested in their physical properties; they tend to be less rigid (lower melting point) and more volatile (lower boiling point) than the corresponding amides. Name: Dicyclohexyl phthalate
Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics