Chapter 4
Downloaded by STANFORD UNIV GREEN LIBR on June 23, 2012 | http://pubs.acs.org Publication Date (Web): November 2, 2010 | doi: 10.1021/bk-2010-1048.ch004
Trace Organics in Arizona Surface and Wastewaters C. Chiu1 and P. K. Westerhoff*,1 1School
of Sustainable Engineering and the Built Environment, Arizona State University, Engineering Center, G-Wing Room ECG252, P.O. Box 5306, Tempe, AZ 85287 *Corresponding author e-mail:
[email protected].
To investigate the occurrence of trace organic compounds (TrOCs) in waters throughout Arizona, 26 compounds (pharmaceuticals and personal care products (PPCPs), endocrine disrupting compounds (EDCs), and artificial sweetener) were analyzed in samples from surface waters, drinking water treatment plants (WTPs), wastewater treatment plants (WWTPs), and a groundwater recharge site during September 2007 to July 2009. Samples were analyzed using liquid chromatography/tandem mass spectrometry (LC/MS/MS). TrOCs were prevalent during this study, as they were found in 95% of the samples collected (n>100). The most frequently detected compounds in surface waters were oxybenzone, caffeine, and sucralose. The total concentration of TrOCs varied seasonally with the highest concentration detected during summer. For WTPs, the majority of TrOCs detected in surface water were also identified in WTP raw waters and sedimentation effluent. High TrOC concentrations were detected in raw wastewater, and certain compounds (e.g. oxybenzone, ibuprofen, DEET, etc.) exhibited an increasing trend during summer. WWTP processes were shown to remove 11 of 26 compounds with up to 98% efficiency. Sucralose and sulfamethoxazole were dominant compounds (>60%) in WWTP effluent. Pharmaceuticals were also present in the ground water system of the Phoenix water supply area ( 1 ug/L
Groundwater at recharge site
Testosterone progesterone, ethinyl estradiol, estradiol and others
Acetaminophen, caffeine, DEET, erythromycin, meprobamate, oxybenzone, pentoxifylline
None
Sulfamethoxazole, sucralose (from one site)
None
Salt River Project waters (Verde River & Salt River)
Testosterone progesterone, ethinyl estradiol, estradiol and others
Sucralose, sulfamethoxazole, acetaminophen, cotinine, dilantin,
Caffeine, DEET
Oxybenzone
None
Testosterone progesterone, ethinyl estradiol, and others
Sulfamethoxazole, oxybenzone, meprobamate, DEET, cotinine, dilantin, carbamazepine, acetaminophen, primidone, estradiol
Caffeine, triclosan
Sucralose
None
89
Downloaded by STANFORD UNIV GREEN LIBR on June 23, 2012 | http://pubs.acs.org Publication Date (Web): November 2, 2010 | doi: 10.1021/bk-2010-1048.ch004
Table 2. Summary of TrOC levels detected in different waters sampled across the state of Arizona
Central Arizona Project Canal from Colorado River
Continued on next page.
In Contaminants of Emerging Concern in the Environment: Ecological and Human Health Considerations; Halden, R.; ACS Symposium Series; American Chemical Society: Washington, DC, 2010.
Source
Activated sludge WWTP with nitrification
Non-detected or < Blank
Testosterone progesterone, ethinyl estradiol, estradiol
2 to 10 ng/L
Acetaminophen, ibuprofen, diazepam, pentoxifylline
90
Downloaded by STANFORD UNIV GREEN LIBR on June 23, 2012 | http://pubs.acs.org Publication Date (Web): November 2, 2010 | doi: 10.1021/bk-2010-1048.ch004
Table 2. (Continued). Summary of TrOC levels detected in different waters sampled across the state of Arizona
Raw wastewater
None
None
10 to 20 ng/L
20 ng/L to 1 ug/L
> 1 ug/L
Cotinine
Caffeine, naproxen, oxybenzone, carbamazepine, hydrocodone, meprobamate, sulfamethoxazole, TBBA, DEET, erythromycin, fluoxetine, trimethoprim, primidone, triclosan, sucralose, dilantin, diclofenac
None
Testosterone, hydrocodone, pentoxifylline, erythromycin, trimethoprim, primidone, fluoxetine carbamazepine, dilantin, diclofenac
Ibuprofen, naproxen, triclosan, sucralose, acetaminophen, caffeine, cotinine, oxybenzone, meprobamate, DEET, TBBA, sulfamethoxazole
Diazepam, Progesterone, Ethinyl Estradiol, Estradiol
In Contaminants of Emerging Concern in the Environment: Ecological and Human Health Considerations; Halden, R.; ACS Symposium Series; American Chemical Society: Washington, DC, 2010.
Downloaded by STANFORD UNIV GREEN LIBR on June 23, 2012 | http://pubs.acs.org Publication Date (Web): November 2, 2010 | doi: 10.1021/bk-2010-1048.ch004
Occurrences of TrOCs in Surface Waters Three surface waters in the Phoenix metropolitan area serving as drinking water sources were investigated in this study: Waddell Canal, Salt River, and Verde River. From September 2007 to July 2009, 24 samples were collected from these three surface waters. One or more TrOCs were found in more than 95% of the 24 surface water samples during the investigation. The TrOC results were compared with lab-blank and field-blank samples to make sure the measurements were significant and not due to artificial error. Table 3 shows the TrOCs detected in the three surface waters during this study. Progesterone was not detected in any surface water samples. Measured concentrations were generally low (less than 50 ng/L); two compounds (oxybenzone and sucralose) exceeded 300 ng/L in some samples during the investigation. Fifteen of 26 target compounds were identified as prevalent anthropogenic contaminants in the surface waters (>50% occurrence); caffeine, DEET, sucralose, and oxybenzone were detected in most samples (>90% occurrence). The occurrence of estradiol was detected near and slightly above our reporting level of 2 ng/L in Arizona surface waters (not shown in Table 3). Although these values are lower than the suggested EC50 value (25 ng/L, conducted with fish) in previous study (54), the occurrence of estradiol is higher in this study than many surface waters reported in the United States (55, 56). Our atypical estradiol detected in surface waters probably results from the detection method which is not suggested for drinking waters and which can show false positives in the analysis of steroid hormones in water. To obtain a broader view of the long-term variation for individual surface waters, the monthly results were divided into two groups, summer and other seasons. Figure 1 shows the monthly total TrOC concentration for different surface waters and the diversified TrOC content between summer and other seasons. Overall, the occurrence of TrOCs in the three surface waters was higher during summer than in other seasons. Salt River water was found to have the highest TrOC concentration during summer (>350 ng/L, on average) but decreased sharply during other seasons (to 120 ng/L). CAP canal and Verde River samples exhibit less variance (30% difference) between summer and other seasons; the CAP canal had the highest total concentration during other seasons. From the point of view of content percentage, sucralose had the highest concentration in the CAP canal at any season (60% to 75%). For the Salt River, oxybenzone accounted for more than 80% of the total TrOCs measured during summer but decreased to 16% during other seasons. The Verde River had the lowest concentration of total TrOCs present, and oxybenzone had the highest concentration among the 26 compounds during summer.
91 In Contaminants of Emerging Concern in the Environment: Ecological and Human Health Considerations; Halden, R.; ACS Symposium Series; American Chemical Society: Washington, DC, 2010.
Table 3. Summary of TrOCs detected in Arizona surface watersa, b CAP canal
Downloaded by STANFORD UNIV GREEN LIBR on June 23, 2012 | http://pubs.acs.org Publication Date (Web): November 2, 2010 | doi: 10.1021/bk-2010-1048.ch004
Verde River
mean detected
mean total
mean detected
mean total
mean detected
mean total
Acetaminophen
4
2
10
2
5
2
Caffeine
17
10
19
11
14
7
Carbamazepine
3
2
2
Cotinine
5
3
4
2
2