In an election year political statements raising ‘hot button’ environmental issues like PFOA and PFOS are to be expected (e.g. click here). Ms. Dingell’s characterization of PFOA and PFOS are not based on science or even a proper understanding of environmental law.
The article below presents the only publicly available, independent peer-reviewed published paper examining the full implications of regulating of PFOA and PFOS in drinking water.
F.W. Pontius. Regulation of Perfluorooctanoic Acid (PFOA) and
Perfluorooctane Sulfonic Acid (PFOS) in Drinking
Water: A Comprehensive Review. Water 2019, 11, 2003; doi:10.3390/w11102003
Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) are receiving global attention due to their persistence in the environment through wastewater effluent discharges and past improper industrial waste disposal. They are resistant to biological degradation and if present in wastewater are discharged into the environment. The US Environmental Protection Agency (USEPA) issued drinking water Health Advisories for PFOA and PFOS at 70 ng/L each and for the sum of the two. The need for an enforceable primary drinking water regulation under the Safe Drinking Water Act (SDWA) is currently being assessed. The USEPA faces stringent legal constraints and technical barriers to develop a primary drinking water regulation for PFOA and PFOS. This review synthesizes current knowledge providing a publicly available, comprehensive point of reference for researchers, water utilities, industry, and regulatory agencies to better understand and address cross-cutting issues associated with regulation of PFOA and PFOS contamination of drinking water.
Liu X, Xiong L, Li D, Chen C, Cao Q. Monitoring and exposure assessment of organophosphorus flame retardants in source and drinking water, Nanjing, China. Environ Monit Assess. 2019 Jan 31;191(2):119. doi: 10.1007/s10661-019-7239-0.
This study developed a new method to determine the residues of 13 organophosphorus flame retardants (OPFRs) in drinking water by gas chromatography-tandem mass spectrometry (GC-MS/MS) technique and investigated the chemical distribution in water samples from municipal plants along the Yangtze River in Nanjing. The linear calibration correlation coefficients R2 for all 13 OPFRs were at least 0.998 0. Three levels of spiked test were performed. Most of the recoveries were in the range of 80~120%, and the relative standard deviations (RSDs) for the 13 OPFRs were 2.1~17% (n = 6). Five OPFRs were 100% positively detected in the samples, and 3 OPFRs were positively detected in some samples. The concentrations of detected OPFR in the water ranged from 0.7 to 5780.0 ng L-1. The average concentrations of OPFRs in wet season were higher than those in dry season, and the contaminants mainly originated from the source water in the Yangtze River. The exposure assessments of individual and total OPFRs were investigated. The estimated daily intakes of total OPFRs via ingestion of drinking water reached up to 64.8 and 45.2 ng/kg bw/day in dry and wet season, respectively. This study demonstrates a profile of OPFR distribution in Nanjing municipal water and provides information on human exposure assessment via drinking water in the Nanjing District, China.
Bieber S, Snyder SA, Dagnino S, Rauch-Williams T, Drewes JE. Management strategies for trace organic chemicals in water – A review of international approaches. Chemosphere. 2017 Dec 16;195:410-426. doi: 10.1016/j.chemosphere.2017.12.100.
To ensure an appropriate management of potential health risks and uncertainties from the release of trace organic chemicals (TOrCs) into the aqueous environment, many countries have evaluated and implemented strategies to manage TOrCs. The aim of this study was to evaluate existing management strategies for TOrCs in different countries to derive and compare underlying core principles and paradigms and to develop suggestions for more holistic management strategies to protect the environment and drinking water supplies from the discharge of undesired TOrCs. The strategies in different industrial countries were summarized and subsequently compared with regards to three particular questions: 1) Do the approaches different countries have implemented manage all or only specific portions of the universe of chemicals; 2) What implementation and compliance strategies are used to manage aquatic and human health risk and what are their pros and cons; and 3) How are site-specific watershed differences being addressed? While management strategies of the different countries target similar TOrCs, the programs differ in several important aspects, including underlying principles, the balance between aquatic or human health protection, implementation methods, and financing mechanisms used to fund regulatory programs.
Nassar R, Mokh S, Rifai A, Chamas F, Hoteit M, Al Iskandarani M. Transformation of sulfaquinoxaline by chlorine and UV light in water: kinetics and by-product identification. Environ Sci Pollut Res Int. 2017 Dec 1. doi: 10.1007/s11356-017-0814-4.
Sulfaquinoxaline (SQX) is an antimicrobial of the sulfonamide class, frequently detected at low levels in drinking and surface water as organic micropollutant. The main goal of the present study is the evaluation of SQX reactivity during chlorination and UV irradiations which are two processes mainly used in water treatment plants. The SQX transformation by chlorination and UV lights (254 nm) was investigated in purified water at common conditions used for water disinfection (pH = 7.2, temperature = 25 °C, [chlorine] = 3 mg L-1). The result shows a slow degradation of SQX during photolysis compared with chlorination process. Kinetic studies that fitted a fluence-based first-order kinetic model were used to determine the kinetic constants of SQX degradation; they were equal to 0.7 × 10-4 and 0.7 × 10-2 s-1 corresponding to the half time lives of 162 and 1.64 min during photolysis and chlorination, respectively. In the second step, seven by-products were generated during a chlorination and photo-transformation of SQX and identified using liquid chromatography with electrospray ionization and tandem mass spectrometry (MS-MS). SO2 extrusion and direct decomposition were the common degradation pathway during photolysis and chlorination. Hydroxylation and isomerization were observed during photodegradation only while electrophilic substitution was observed during chlorination process.
Unyimadu JP, Osibanjo O, Babayemi JO. Selected persistent organic pollutants (POPs) in water of River Niger: occurrence and distribution. Environ Monit Assess. 2017 Dec 6;190(1):6. doi: 10.1007/s10661-017-6378-4.
This study assessed the levels and distribution of selected persistent organic pollutants (POPs) in water of River Niger. The selected POPs of interest were organochlorine pesticides (OCPs). Fifteen representative sites along River Niger: three each from Gurara River (tributary) in Niger State, Lokoja (confluence) in Kogi State, Onitsha in Anambra State, Brass and Nicolas Rivers (tributaries) in Bayelsa State were selected for sampling quarterly over a 24-month period. A total of 240 surface and bottom water samples were collected using Van Dorn water sampler in the eight quarters of 2008-2009. At the Delta locations where tidal effects take place, high- and low-tide water samples were taken as compared to surface and bottom at the River Niger locations. For sample extraction, EPA method 3510c was employed with slight modifications. Certified reference standards from Accustandards USA was used for the instrument calibration and quantification of OCPs. The extracted samples were subjected to gas chromatography (GC/ECD) for identification/quantification. And Shimadzu GCMS QP2010 was used for confirmation. Chlordane, endosulfan, endrin and DDT metabolites were very prominent in the water samples, compared to HCH, dieldrin, and isomers which occurred at lower concentrations. The sequence in the concentration of the organochlorine pesticides were ∑chlordane > ∑DDT > ∑endosulfan > ∑endrine > ∑dieldrin > ∑HCH. The highest concentration of ∑OCPs in water samples of River Niger, 1138.0 ± 246.7 ng/L, with range 560.8-1629 ng/L was detected at Onitsha location, while the lowest concentration, 292.6 ± 74.9, with range 181-443.0 ng/L was detected at Nicolas River. Levels of OCPs in a larger percentage of the samples exceeded guidelines and therefore hold potential harmful effects on benthic fauna, fish, and man. Abstraction of water from the River for drinking water treatment should be discouraged. Because of the potential danger, this presents, continuous monitoring of the water body and if possible remediation, determination of the sources of the POPs is therefore very necessary.
Ben W, Zhu B, Yuan X, Zhang Y, Yang M, Qiang Z. Occurrence, removal and risk of organic micropollutants in wastewater treatment plants across China: Comparison of wastewater treatment processes. Water research. 2017 Nov 30;130:38-46. doi: 10.1016/j.watres.2017.11.057.
This study investigated the occurrence, removal and risk of 42 organic micropollutants (MPs), including 30 pharmaceuticals and personal care products and 12 endocrine disrupting chemicals, in 14 municipal wastewater treatment plants (WWTPs) distributed across China. The composition profiles of different MP categories in the influent, effluent, and excess sludge were explored and the aqueous removal efficiencies of MPs were determined. Quantitative meta-analysis was performed to compare the efficacies of different wastewater treatment processes in eliminating MPs. Results indicate that different MP categories showed quite similar distributions among the studied WWTPs, with phenolic estrogenic compounds (PEs), macrolides, and fluoroquinolones being always dominant in the influent, effluent and excess sludge. Tetracyclines, bezafibrate, caffeine, steroid estrogens, and PEs showed high and stable aqueous removal efficiencies, whereas other MPs showed considerably varied aqueous removal efficiencies. Anaerobic/anoxic/oxic process combined with a moving-bed biofilm reactor achieved the highest aqueous removal of MPs among various secondary treatment processes. A combined process consisting of ultrafiltration, ozonation and ClO2 disinfection resulted in the highest removal of MPs among the tertiary treatment processes. Sulfamethoxazole, ofloxacin, ciprofloxacin, clarithromycin, erythromycin, estrone, and bisphenol A in the effluent, as well as β-estradiol 3-sulfate in the excess sludge could pose high risks. This study draws an overall picture about the current status of MPs in WWTPs across China and provides useful information for better control of the risks associated with MPs.
Shi P, Zhou S, Xiao H, Qiu J, Li A, Zhou Q, Pan Y, Hollert H. Toxicological and chemical insights into representative source and drinking water in eastern China. Environmental pollution 2017 Oct 17;233:35-44. doi: 10.1016/j.envpol.2017.10.033.
Drinking water safety is continuously threatened by the emergence of numerous toxic organic pollutants (TOPs) in environmental waters. In this study, an approach integrating in vitro bioassays and chemical analyses was performed to explore toxicological profiles of representative source and drinking water from waterworks of the Yangtze River (Yz), Taihu Lake (Th), and the Huaihe River (Hh) basins in eastern China. Overall, 34 of 96 TOPs were detected in all water samples, with higher concentrations in both source and drinking water samples of Hh, and pollutant profiles also differed across different river basins. Non-specific bioassays indicated that source water samples of Hh waterworks showed higher genotoxicity and mutagenicity than samples of Yz and Th. An EROD assay demonstrated dioxin-like toxicity which was detected in 5 of 7 source water samples, with toxin concentration levels ranging from 62.40 to 115.51 picograms TCDD equivalents per liter of water (eq./L). PAHs and PCBs were not the main contributors to observed dioxin-like toxicity in detected samples. All source water samples induced estrogenic activities of 8.00-129.00 nanograms 17β-estradiol eq./L, and estrogens, including 17α-ethinylestradiol and estriol, contributed 40.38-84.15% of the observed activities in examined samples. While drinking water treatments efficiently removed TOPs and their toxic effects, and estrogenic activity was still observed in drinking water samples of Hh. Altogether, this study indicated that the representative source water in eastern China, especially that found in Hh, may negatively affect human health, a finding that demonstrates an urgent requirement for advanced drinking water treatments.