1 Pharmaceuticals, Personal Care Products, and Artificial …
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investigated pharmaceuticals in aquatic environments. In 2013, the global consumption of caffeine was almost 1 million tons, and this number has been increasing at a
rate greater than that of population growth (Quadra et al. 2020). Consequently, the
caffeine levels in raw wastewater reach tens of a microgram per liter in many parts
of the world (Quadra et al. 2020). In contrast, the detection frequency of caffeine
in groundwater varies considerably (3–100%), with varying maximum concentrations (15–16,249 ng/L). This variable occurrence of caffeine in groundwater would
be partly due to its lability to biodegradation (Buerge et al. 2003). In comparison,
carbamazepine is known to be highly resistant to biodegradation (Clara et al. 2004;
Tran et al. 2019). Therefore, despite being far less consumed (e.g., estimated at 1014
tons per year; Zhang et al. 2008) and far less abundant in Asian wastewater (e.g.,
tens to hundreds of ng/L; Tran et al. 2014b) than caffeine, carbamazepine has been
detected as ubiquitously as caffeine, with a maximum concentration of 117 ng/L
(Tokyo, Japan; Nakada et al. 2008).
Among the Asian countries, crotamiton, an antipruritic (anti-itching) pharmaceutical for treating scabies, has been detected at high concentrations (up to 1400 ng/L)
only in Japanese groundwater. This would likely be due to its high consumption in
Japan, as it is abundant in Japanese raw wastewater (median 921 ng/L; Nakada et al.
2006) compared to the raw wastewater in other countries (e.g., median 34.6 ng/L in
Singapore; Tran et al. 2014b and 60 ng/L in Switzerland; Kahle et al. 2009). Crotamiton shows high persistence during biological wastewater treatment processes
(Nakada et al. 2006), but appears to be less persistent than carbamazepine over a
long residence time in groundwater (Kuroda et al. 2012).
The concentrations of these PPCPs in Asian groundwater are comparable to or
lower than in North America and Europe (Jurado et al. 2012; Kahle et al. 2009;
Lapworth et al. 2012; Postigo and Barceló 2015; Sui et al. 2015).
1.4.3 Artificial Sweeteners and DEET
ASs are ubiquitous in Asian groundwater. In many studies, the detection frequencies of acesulfame, cyclamate, and sucralose were more than 50%, and the maximum
concentrations more than 100 ng/L (Table 1.5). In comparison, the abundance of individual ASs varied widely among the studies and countries. For example, in China,
acesulfame and sucralose had a greater concentration range than cyclamate and saccharin, in groundwater from the Dongjiang River Basin (Yang et al. 2018), but in
Tianjin, cyclamate and saccharin were more abundant than sucralose and acesulfame
(Gan et al. 2013). In Singapore, acesulfame, cyclamate, and saccharin showed similar
detection frequency (35.9–43.8%) and concentration range (mean: 39–65 ng/L), but
sucralose was not detected. The maximum concentrations of ASs in Asian groundwater ranged from 790 ng/L for cyclamate (Singapore; Tran et al. 2014a) to 4580 ng/L
for acesulfame (China; Yang et al. 2018). These AS concentrations were comparable
or slightly less than in groundwater in North America (Buerge et al. 2009; Engelhardt
et al. 2011) or Europe (Van Stempvoort et al. 2011; Van Stempvoort et al. 2013).
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investigated pharmaceuticals in aquatic environments. In 2013, the global consumption of caffeine was almost 1 million tons, and this number has been increasing at a
rate greater than that of population growth (Quadra et al. 2020). Consequently, the
caffeine levels in raw wastewater reach tens of a microgram per liter in many parts
of the world (Quadra et al. 2020). In contrast, the detection frequency of caffeine
in groundwater varies considerably (3–100%), with varying maximum concentrations (15–16,249 ng/L). This variable occurrence of caffeine in groundwater would
be partly due to its lability to biodegradation (Buerge et al. 2003). In comparison,
carbamazepine is known to be highly resistant to biodegradation (Clara et al. 2004;
Tran et al. 2019). Therefore, despite being far less consumed (e.g., estimated at 1014
tons per year; Zhang et al. 2008) and far less abundant in Asian wastewater (e.g.,
tens to hundreds of ng/L; Tran et al. 2014b) than caffeine, carbamazepine has been
detected as ubiquitously as caffeine, with a maximum concentration of 117 ng/L
(Tokyo, Japan; Nakada et al. 2008).
Among the Asian countries, crotamiton, an antipruritic (anti-itching) pharmaceutical for treating scabies, has been detected at high concentrations (up to 1400 ng/L)
only in Japanese groundwater. This would likely be due to its high consumption in
Japan, as it is abundant in Japanese raw wastewater (median 921 ng/L; Nakada et al.
2006) compared to the raw wastewater in other countries (e.g., median 34.6 ng/L in
Singapore; Tran et al. 2014b and 60 ng/L in Switzerland; Kahle et al. 2009). Crotamiton shows high persistence during biological wastewater treatment processes
(Nakada et al. 2006), but appears to be less persistent than carbamazepine over a
long residence time in groundwater (Kuroda et al. 2012).
The concentrations of these PPCPs in Asian groundwater are comparable to or
lower than in North America and Europe (Jurado et al. 2012; Kahle et al. 2009;
Lapworth et al. 2012; Postigo and Barceló 2015; Sui et al. 2015).
1.4.3 Artificial Sweeteners and DEET
ASs are ubiquitous in Asian groundwater. In many studies, the detection frequencies of acesulfame, cyclamate, and sucralose were more than 50%, and the maximum
concentrations more than 100 ng/L (Table 1.5). In comparison, the abundance of individual ASs varied widely among the studies and countries. For example, in China,
acesulfame and sucralose had a greater concentration range than cyclamate and saccharin, in groundwater from the Dongjiang River Basin (Yang et al. 2018), but in
Tianjin, cyclamate and saccharin were more abundant than sucralose and acesulfame
(Gan et al. 2013). In Singapore, acesulfame, cyclamate, and saccharin showed similar
detection frequency (35.9–43.8%) and concentration range (mean: 39–65 ng/L), but
sucralose was not detected. The maximum concentrations of ASs in Asian groundwater ranged from 790 ng/L for cyclamate (Singapore; Tran et al. 2014a) to 4580 ng/L
for acesulfame (China; Yang et al. 2018). These AS concentrations were comparable
or slightly less than in groundwater in North America (Buerge et al. 2009; Engelhardt
et al. 2011) or Europe (Van Stempvoort et al. 2011; Van Stempvoort et al. 2013).