Occurrence of pharmaceuticals in the wastewater of a Greek hospital: Combining consumption data collection and LC-QTOF-MS analysis.

In this article we applied drug consumption approach and chemical analysis in parallel to investigate the concentrations of a large number of pharmaceuticals in different streams of a General Hospital. Drugs consumption data was collected during two periods (Period 1, 2) and the predicted environmental concentrations (PECs) were estimated for the wastewater of a building housing specific medical services (Point A) and for the entire hospital (Point B). Hospital wastewater samples (HWW) samples were also collected from these points and periods and the measured environmental concentrations (MEC) were determined using UHPLC-ESI-QTOF-MS/MS. According to consumption data, the highest number of drugs was consumed in the departments of Hematology, Intensive Care Unit, Cardiology, Internal Medicine, and Oncology, while the number of active substances used in the hospital was 413 (Period 1) and 362 (Period 2). For most substances, much higher PEC and MEC values were found at the HWW of Point A indicating that on-site treatment of this stream could be examined in the future. The application of wide-scope target analysis allowed the quantification of 122 compounds, while 21 additional substances were identified using suspect screening. The highest mean concentrations in Period 1 were found for acetaminophen (1100 µg/L) and rifaximin (723 µg/L), while in Period 2 for iopromide (458 µg/L) and acyclovir (408 µg/L). Among the detected compounds, 19 metabolites were determined. Atenolol acid, 1-hydroxy-midazolam and clopidogrel carboxylic acid were quantified at concentrations much higher than parent compounds indicating the importance of metabolites' monitoring in HWW. Calculation of PEC/MEC ratio for 36 pharmaceuticals showed sufficient correlation of these values for 19 % to 33 % of the substances depending on the examined period and sampling point. The parallel collection of drugs consumption data and chemical analysis give a thorough picture of the substances present in HWW and their main sources, facilitating decision-making for their better management.

Oil refinery sludge and green waste simulated windrow composting.

Oil refinery sludge (ORS) was mixed with shredded green wastes (GW) at ratios of 1:1 v/v (RI) and 1:3 v/v (RII). The mixtures, of approximately volumes of 1,020 l and 990 l respectively, were introduced in metal cubic containers of 1.0 m(3) volume, opened at the top and with small holes punctured in the bottom and the side. The containers were additionally insulated with a layer of rockwool (20 mm). The boxes were emptied, the mixtures were turned and water was added occasionally, in one to two weeks intervals, simulating a windrow composting system. Temperature, physiochemical characteristics, mineral oil and grease (MOG) concentration, polycyclic aromatic hydrocarbons (PAHs) concentration, carbon dioxide emission, methane emission and microorganisms presence were recorded either daily or every time the mixtures were turned, for a period of 120 days. RII recorded temperatures as high as 62 degrees C, reaching 56 degrees C in Day 6 and retained temperatures above 50 degrees C for more than 40 days. RI recorded its highest temperature of 53 degrees C in Day 77. The reason why the two mixtures behaved so differently can be explained by: (i) extended co-digestion phenomena by the microorganisms decomposing the GW in RII, (ii) toxic effect of ORS in RI due to the far larger amounts used (840 kg in RI in comparison with the 460 kg in RII). After Day 36 temperature increased gradually in RI and MOG and PAHs reduction was first noted. At the end of the experiment MOG concentration in RI was 57.2 mg/kg dry weight (dw) (52.1% reduction) where in RII was 34.3 mg/kg dw (62.1% reduction). Emissions of methane and carbon dioxide support the concept of the toxic effect and the delay ignition of the decomposing process in RI. In total, CO(2) and CH(4) emissions from RI were recorded to be 30.8 kg and 18.5 g, respectively, where from RII 59.6 kg of CO(2) and 6.4 g of CH(4) were emitted. An effort was made to determine the effect of temperature alone (as an abiotic treating parameter) in both mixtures. It can be supported that about least 15% of the MOG and PAHs removal.

Constructed wetlands treating highway runoff in the central Mediterranean region.

Two free water surface (FWS) and two subsurface flow (SSF) pilot-size constructed wetlands treating highway runoff (HRO) were monitored over a period of two years (September 2005-August 2007). One FWS and one SSF were designed with a hydraulic retention time (HRT) of 12h, named FWS12 and SSF12, respectively, with each one capable of treating a maximum HRO of 12.6 m(3) d(-1). The other couple, named FWS24 and SSF24, respectively, was designed with an HRT of 24h, with each receiving a maximum HRO of 6.3 m(3) d(-1). The influent flowed from a highway section with a total surface 2752 m(2) on the island of Crete, Greece, in the heart of the South-Central Mediterranean region. Influent and effluent were monitored for COD, TSS, total N (TN), NO(3)(-) and total P (TP) concentrations. Furthermore, removal efficiencies were examined for heavy metals (Cu, Ni, Pb, Zn) for both years, while polycyclic aromatic compounds (PAHs) were examined for the period between September 2006 and August 2007. The influent had a two-year average COD value of 101 mg l(-1), whereas the mean values for TSS, TN, N-NO(3)(-) and TP were 203, 4.30, 1.25 and 4.17 mg l(-1), respectively. For Cu, Ni, Pb and Zn the respective two-year mean influent concentrations were 56, 114, 49 and 250 microg l(-1). Mean concentration of total PAHs in runoff (summation operator PAHs, 16 compounds) were 12.01 microg l(-1). The performance among the four beds was not significantly different according to ANOVA analysis followed by Tukey test (at p<0.05) for almost all the above physicochemical parameters, suggesting that all systems performed in a similar way. All studied systems, achieved a mean of two-year removal efficiencies of 47% for COD, 89% for TSS, 49% for TN, 58% for N-NO(3)(-), 60% for TP, 47% for Cu, 23% for Ni, 33% for Pb, 61% for Zn and 59% for summation operator PAHs (16 compounds).

Evaluation of primary and secondary treated and disinfected wastewater irrigation of tomato and cucumber plants under greenhouse conditions, regarding growth and safety considerations.

Tomato and cucumber seedlings were distributed into 10 groups (five for each plant) of 15 plants each. The plants were irrigated for 10 weeks with primary treated wastewater (group A), secondary treated wastewater (group B), chlorinated secondary treated wastewater (group C), a fertilizer dilution (group F), and tap water (group M). All precautions were taken to secure that there was no direct contact between the wastewater and the edible portions of the crops. During this period and on a weekly basis, the height and number of leaves was monitored, while, at the end, the dry weight of leaves, stems, and roots for each plant of each group was measured. Based on these growth parameters, both types of plant in groups A and F recorded the most significant development compared to the other three groups. The plants irrigated with tap water recorded the smallest development, in every case. Plants in groups B and C were similar, with a slight (but not significant) superiority for the plants irrigated with secondary treated wastewater, probably as a result of some phytotoxic effects of residual chloride in the chlorinated wastewater. The presence of nutrients and specifically nitrogen in the various solutions explains the differences satisfactorily. The vegetables grown on the plants of each group were harvested, and their surface tissue analyzed for total coliforms (TC) and enterococci (EC). Tomatoes grown on the plants of groups A and B recorded the highest values for TC, with 505 and 490 cfu/g, respectively, whereas, for cucumbers, those values were 342 and 450 cfu/g, respectively. Enterococci were detected on the surface of harvested vegetables from groups A and B, but the small number of cases and their random character cannot support any strong relations between the used wastewater and their presence. The TC values in group C were very low, far lower than those if group F. No EC were found in either group C or group F. These primary results suggested that irrigation with appropriate disinfected wastewater, even of such high-risk cultivations of vegetables eaten raw, should not be discarded completely as unsafe, but be reconsidered and studied further. However, the use of undisinfected wastewater in such greenhouse cultivations, where all safety precautions have been taken to prevent any contact of the fruits with the soil or the wastewater, does not prove to be 100% safe.