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Pietermaritzburg, South Africa

Manickum T.,Scientific Services Laboratories Chemical science | John W.,Scientific Services Laboratories Chemical science
Analytical and Bioanalytical Chemistry | Year: 2015

The availability of national test centers to offer a routine service for analysis and quantitation of some selected steroid hormones [natural estrogens (17-β-estradiol, E2; estrone, E1; estriol, E3), synthetic estrogen (17-α-ethinylestradiol, EE2), androgen (testosterone), and progestogen (progesterone)] in wastewater matrix was investigated; corresponding internationally used chemical- and immuno-analytical test methods were reviewed. The enzyme-linked immunosorbent assay (ELISA) (immuno-analytical technique) was also assessed for its suitability as a routine test method to quantitate the levels of these hormones at a sewage/wastewater treatment plant (WTP) (Darvill, Pietermaritzburg, South Africa), over a 2-year period. The method performance and other relevant characteristics of the immuno-analytical ELISA method were compared to the conventional chemical-analytical methodology, like gas/liquid chromatography-mass spectrometry (GC/LC-MS), and GC-LC/tandem mass spectrometry (MSMS), for quantitation of the steroid hormones in wastewater and environmental waters. The national immuno-analytical ELISA technique was found to be sensitive (LOQ 5 ng/L, LOD 0.2-5 ng/L), accurate (mean recovery 96 %), precise (RSD 7-10 %), and cost-effective for screening and quantitation of these steroid hormones in wastewater and environmental water matrix. A survey of the most current international literature indicates a fairly equal use of the LC-MS/MS, GC-MS/MS (chemical-analytical), and ELISA (immuno-analytical) test methods for screening and quantitation of the target steroid hormones in both water and wastewater matrix. Internationally, the observed sensitivity, based on LOQ (ng/L), for the steroid estrogens E1, E2, EE2, is, in decreasing order: LC-MSMS (0.08-9.54) > GC-MS (1) > ELISA (5) (chemical-analytical > immuno-analytical). At the national level, the routine, unoptimized chemical-analytical LC-MSMS method was found to lack the required sensitivity for meeting environmental requirements for steroid hormone quantitation. Further optimization of the sensitivity of the chemical-analytical LC-tandem mass spectrometry methods, especially for wastewater screening, in South Africa is required. Risk assessment studies showed that it was not practical to propose standards or allowable limits for the steroid estrogens E1, E2, EE2, and E3; the use of predicted-no-effect concentration values of the steroid estrogens appears to be appropriate for use in their risk assessment in relation to aquatic organisms. For raw water sources, drinking water, raw and treated wastewater, the use of bioassays, with trigger values, is a useful screening tool option to decide whether further examination of specific endocrine activity may be warranted, or whether concentrations of such activity are of low priority, with respect to health concerns in the human population. The achievement of improved quantitation limits for immuno-analytical methods, like ELISA, used for compound quantitation, and standardization of the method for measuring E2 equivalents (EEQs) used for biological activity (endocrine: e.g., estrogenic) are some areas for future EDC research. © 2015 Springer-Verlag. Source


Manickum T.,Scientific Services Laboratories Chemical science | John W.,Scientific Services Laboratories Chemical science | Terry S.,Water Quality and Environmental Services | Hodgson K.,Water Quality and Environmental Services
Journal of Environmental Radioactivity | Year: 2014

Raw and potable water sample sources, from the Umgeni Water catchment areas (rivers, dams, boreholes) in central KwaZulu-Natal (South Africa), were screened for Uranium concentration and alpha and beta radioactivity. Test methods used were gas flow proportional counting for alpha-beta radioactivity, and kinetic phosphorescence analysis (KPA), for Uranium. The uranium levels (median=0.525μg/L, range=<0.050-5.010) were well below the international World Health Organization (WHO) (2011) guideline for drinking-water quality (≤15μg/L). The corresponding alpha and beta radioactivity was ≤0.5Bq/L (median=0.084, Interquartile Range (IR)=0.038, range=0.018-0.094), and ≤1.0Bq/L (median=0.114, IR=0.096, range=0.024-0.734), respectively, in compliance with the international WHO limits. For uranium radionuclide, the average dose level, at uranium level of ±0.525μg/L, was 0.06μSv/a, which complies with the WHO reference dose level for drinking water (<0.1mSv/a). There was a distinct trend of cluster of relatively higher Uranium levels of some sources that were found to be associated with the geology/geography and groundwater sources. Overall, the radiological water quality classification, with respect to WHO, is "Blue" - ideal; additional physicochemical analyses indicated good water quality. The analytical test methods employed were found to be suitable for preliminary screening for potential radioactive "hot spots". The observed Uranium levels, and the alpha/beta radioactivity, indicate contribution largely from Naturally Occurring Radioactive Material (NORM), with no significant health risk to humans, or to the environment. © 2014 Elsevier Ltd. Source


Manickum T.,Scientific Services Laboratories Chemical science | John W.,Scientific Services Laboratories Chemical science
Science of the Total Environment | Year: 2013

Steroid hormone Endocrine Disrupting Compounds (EDCs) (natural estrogens (17-β-estradiol (E2), estrone (E1), estriol (E3), synthetic estrogen (17-α-ethinylestradiol (EE2)), natural androgen (testosterone) (tes) and natural progestogen (progesterone) (pro)) at an activated sludge wastewater works (WWW), were quantitated using Enzyme-linked immunosorbent assay (ELISA). The steroid hormone profile in the adjacent surface water was also determined. Pro was the most abundant (41%, 408. ng/L) in the influent, followed by tes (35%, 343. ng/L) and E2 (12%, 119. ng/L). E1 was the most abundant (35%, 23. ng/L) in effluent, followed by E2 (30%, 20. ng/L) and tes (17%, 11. ng/L). Chemical removal efficiencies of the steroid hormones by the WWW averaged 92%. High removal efficiency was observed for pro (98%. ±. 2) and tes (96%. ±. 1), compared to natural (72-100%) and synthetic estrogen (90%. ±. 3), with biodegradation being the major removal route for pro and tes. The lowest removal for E2 is in spring (65%), and maximum removal is in winter (95%). Natural (E2, E1) and synthetic estrogen (EE2) were major contributors to influent (E2. =. 69%) and effluent (E2 = 73%) estrogenic potency. The estrogenic potency removal averaged 85% (range: 73-100). Risk assessment of the steroid hormones present in wastewater effluent, and surface water, indicated that EE2 and E2 pose the highest risk to human health and fish. EE2 was found to be much more resistant to biodegradation, compared to E2, in surface water. Estrone, as the breakdown product of E2 and EE2 in wastewater, appears to be suitable as an indicator of EDCs. The study suggests that a battery of tests: quantitative chemical assay, bioassay for estrogenic activity and risk assessment methods, collectively, are preferred in order to make meaningful, accurate conclusions regarding potential adverse effects of EDCs present in treated wastewater effluent or surface water, to the aquatic environment, human health, and wildlife systems. © 2013 Elsevier B.V. Source

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