compounds, some are chiral in nature, for example, bis-(2-ethylhexyl) phthalate,
bis-(2-propylheptyl) phthalate, bis-(2-ethylhexyl) phthalate, tris-(2-ethylhexyl)trimellitate, trioctyl trimellitate, bis-(2-ethylhexyl) adipate, dioctyl terephthalate,
1,2-cyclohexane dicarboxylic acid diisononyl ester, 1,2,4-butanetriol trinitrate,
trimethylolethane trinitrate, etc. Zolfaghari et al. (2015) reviewed the status of
pollution due to a typical plasticiser, Di-2-ethyl-hexyl phthalate (DEHP). The
authors describe surface and waste waters and landfill leachates as the major sources
of pollution. Similarly, Wei et al. reviewed the sources of pollution of the plasticisers
and flame retardants (additives) as well as toxicity exposure risk (Wei et al. 2015).
The authors identified a wide variety of commercial products and wastewater
discharge as possible pollution sources.
Plasticisers and other additives to organic polymers are today considered ubiquitously distributed global pollutants with relevance for human exposure due to their
presentence in mainly daily life products in western industrialised societies. Both
indoor and ambient exposure profiles are reported (Bollmann et al. 2012; Greaves
and Letcher 2017; Zhong et al. 2017; Rodgers et al. 2018; Funk et al. 2019; Liang
et al. 2019). Specifically, plasticiser and additive exposure of young children and
toddlers and the associated toxic consequences of exposure due to plastic toys is
vividly discussed in the public (Xu et al. 2009; Aleksa et al. 2012; Ionas et al. 2014;
Cequier et al. 2015; Dodson et al. 2015; Mizouchi et al. 2015; Wei et al. 2015;
Fatunsin et al. 2020).
In addition, plastic products and wastes, discarded after usage in the environment
(one-way products or defect products), are today considered as potential carriers for
other persistent hydrophilic pollutants (such as chiral POPs, pesticides and PAH
metabolites), adsorbed onto polymer surfaces in the aquatic environment and
transported with the plastic over large distances (Rani et al. 2015; Kwon et al.
2017; Gerdes et al. 2019; Tan et al. 2019; Pozo et al. 2020).
Although, most of the plasticisers, impurities and other additives are not chiral
compounds, for several of those indicator substances, chiral metabolites are identified, allowing compound-specific enantiomer-selective validations of bioavailability, transformation profiles and source elucidation for comprehensive risk
assessment (Hauck et al. 1990; Chen 2011; Heeb et al. 2012).
The main sources of plasticiser pollution are listed in Table 9.5.
9.7 Phenolic Compounds
Some phenols are chiral in nature due to the presence of a stereogenic centre or
because they exhibit planar or axial chirality. Some important chiral phenols are
cavicularin, catechin, 4-nonylphenol, etc. It is interesting to note that cavicularin is a
natural phenolic secondary metabolite isolated from the liverwort Cavicularia
densa. This macrocycle is unusual because it was the first compound to be isolated
from nature, displaying optical activity solely due to the presence of planar chirality
and axial chirality (Zhang et al. 2007; Takagaki and Nanjo 2013).
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9 Source Characterisation and Contamination
bis-(2-propylheptyl) phthalate, bis-(2-ethylhexyl) phthalate, tris-(2-ethylhexyl)trimellitate, trioctyl trimellitate, bis-(2-ethylhexyl) adipate, dioctyl terephthalate,
1,2-cyclohexane dicarboxylic acid diisononyl ester, 1,2,4-butanetriol trinitrate,
trimethylolethane trinitrate, etc. Zolfaghari et al. (2015) reviewed the status of
pollution due to a typical plasticiser, Di-2-ethyl-hexyl phthalate (DEHP). The
authors describe surface and waste waters and landfill leachates as the major sources
of pollution. Similarly, Wei et al. reviewed the sources of pollution of the plasticisers
and flame retardants (additives) as well as toxicity exposure risk (Wei et al. 2015).
The authors identified a wide variety of commercial products and wastewater
discharge as possible pollution sources.
Plasticisers and other additives to organic polymers are today considered ubiquitously distributed global pollutants with relevance for human exposure due to their
presentence in mainly daily life products in western industrialised societies. Both
indoor and ambient exposure profiles are reported (Bollmann et al. 2012; Greaves
and Letcher 2017; Zhong et al. 2017; Rodgers et al. 2018; Funk et al. 2019; Liang
et al. 2019). Specifically, plasticiser and additive exposure of young children and
toddlers and the associated toxic consequences of exposure due to plastic toys is
vividly discussed in the public (Xu et al. 2009; Aleksa et al. 2012; Ionas et al. 2014;
Cequier et al. 2015; Dodson et al. 2015; Mizouchi et al. 2015; Wei et al. 2015;
Fatunsin et al. 2020).
In addition, plastic products and wastes, discarded after usage in the environment
(one-way products or defect products), are today considered as potential carriers for
other persistent hydrophilic pollutants (such as chiral POPs, pesticides and PAH
metabolites), adsorbed onto polymer surfaces in the aquatic environment and
transported with the plastic over large distances (Rani et al. 2015; Kwon et al.
2017; Gerdes et al. 2019; Tan et al. 2019; Pozo et al. 2020).
Although, most of the plasticisers, impurities and other additives are not chiral
compounds, for several of those indicator substances, chiral metabolites are identified, allowing compound-specific enantiomer-selective validations of bioavailability, transformation profiles and source elucidation for comprehensive risk
assessment (Hauck et al. 1990; Chen 2011; Heeb et al. 2012).
The main sources of plasticiser pollution are listed in Table 9.5.
9.7 Phenolic Compounds
Some phenols are chiral in nature due to the presence of a stereogenic centre or
because they exhibit planar or axial chirality. Some important chiral phenols are
cavicularin, catechin, 4-nonylphenol, etc. It is interesting to note that cavicularin is a
natural phenolic secondary metabolite isolated from the liverwort Cavicularia
densa. This macrocycle is unusual because it was the first compound to be isolated
from nature, displaying optical activity solely due to the presence of planar chirality
and axial chirality (Zhang et al. 2007; Takagaki and Nanjo 2013).
262
9 Source Characterisation and Contamination