Analysis and fate of 14 relevant wastewater-derived organic pollutants in long-term exposed soil

A Novel Apparatus for the Fully Automated Extraction and Online Liquid Chromatographic Analysis of Solid Environmental Samples: Application to the Pressurized Hot Water Extraction of Pharmaceuticals in Soil

A new self-assembled apparatus for the extraction of solid samples was designed and implemented to perform a recirculated pressurized hot water extraction (R-PHWE) directly coupled to liquid chromatography-tandem mass spectrometry. To investigate the potential of this new extraction apparatus, 34 target pharmaceutical compounds were analyzed in loam, silt-loam, and silty-clay-loam soils. The target analytes were characterized by heterogeneous physicochemical properties (e.g., -1.60 ≤ log D ≤ 5.91 at pH = 7.2, i.e., at the mean pH values of the three soils). Design of experiments (DoE) was used to identify the best extraction conditions for the target analytes by studying temperature, pressure, and number of extraction cycles. The results of DoE optimization pointed out the significant influence of the number of cycles on recovery. The application of DoE set point to the three reference soils provided recoveries ≥60% for 21-25 out the 34 target analytes, depending on soil. Good recovery precision (<25%) and moderate suppressive matrix effect (≤40%) were found for most target analytes, regardless of the soil considered. The optimized R-PHWE procedure evidenced statistically higher recoveries for 16 out of 34 target analytes when compared to conventional off-line dynamic PHWE.

Evaluation of different QuEChERS-based methods for the extraction of 48 wastewater-derived organic contaminants from soil and lettuce root using high-resolution LC-QTOF with MRMHR and SWATH acquisition modes

The reuse of treated wastewater in agriculture is an important route of introducing a large number of organic contaminants into the agroecosystem. In this study, a modified QuEChERS-based approach was developed for rapid, simple, and simultaneous extraction of 48 organic wastewater-derived contaminants from soil and lettuce root. Twenty-two different (modification) scenarios of the known (or original) QuEChERS method have been tested, in order to obtain best and well-compromised recoveries for all target compounds for soil and roots. Finally, a common method was chosen for both matrices consisting of a single extraction step using EDTA-Mcllvaine buffer and the unbuffered Original QuEChERS salts. Method performance was accomplished by liquid chromatography coupled with high-resolution mass spectrometry on a QToF-MS system using two different acquisition modes, the ultra-fast high-resolution multiple reaction monitoring (MRMHR) mode and the innovative Sequential Window Acquisition of All Theoretical Fragment-Ion (SWATH) mode. Performance characterization was evaluated in terms of recovery, linearity, intra-day precision, method detection limits (MDLs), method quantification limits (MQLs), and matrix effect (ME). Recoveries in MRMHR mode ranged from 63 to 111% and 54 to 104% for lettuce root and soil, respectively, for most of compounds in MRMHR mode and from 56 to 121% and 54 to 104% for lettuce root and soil, respectively, for most of compounds in SWATH. Whereas, MQLs ranged from 0.03 to 0.92 ng g-1 in MRMHR and from 0.03 to 82 ng g-1 in SWATH for lettuce root, and from 0.02 to 0.44 ng g-1 in MRMHR and 0.02 to 0.14 ng g-1 in SWATH for soil. The method was then applied to follow the target compounds in soil and lettuce root, where the system lettuce-soil was irrigated with treated wastewater under real greenhouse conditions. Five and 17 compounds were detected in lettuce root and soil, respectively.

Prioritization of organic contaminants in a reclaimed water irrigation system using wide-scope LC-HRMS screening

A prioritization procedure was developed and implemented at the local level to identify the most relevant organic contaminants of emerging concern (CECs) in an agricultural area irrigated with reclaimed water. A wide-scope screening methodology based on UPLC-HRMS analysis was applied to holistically characterize the CEC footprint in water and its spatial and temporal variations. One hundred and fifty-eight CECs, including pharmaceuticals, industrial chemicals, and pesticides, among others, were identified with a confidence level of 2 in the water samples investigated. After water treatment in the reclamation plant and transport within the irrigation channel network, more than a hundred compounds were still detected at the location where water is abstracted for crop irrigation. Compound ecotoxicity and occurrence (semi-quantified concentrations or peak intensity) were the parameters used to prioritize CECs in the water used for irrigation. Results pointed at venlafaxine, O-desmethyl-venlafaxine, galaxolidone, theophylline/paraxanthine, oxybenzone, and N-phenyl-1-naphtylamine, among others, as CECs of concern in the investigated area. This study provides a simple and cost-effective approach to detecting site-specific priority pollutants that could otherwise be overlooked by national or European regulations. The prioritization tool provided contributes to rationally designing monitoring and attenuation programs and efficiently managing water resources, by ensuring the safety of reclaimed water applications.

Dissipation of twelve organic micropollutants in three different soils: Effect of soil characteristics and microbial composition

The dissipation kinetics and half-lives of selected organic micropollutants, including pharmaceuticals and others, were systematically investigated and compared among different soil types. While some pollutants (e.g., atorvastatin, valsartan, and bisphenol S) disappeared rapidly in all the tested soils, many of them (e.g., telmisartan, memantine, venlafaxine, and azithromycin) remained persistent. Irrespective of the soil characteristics, venlafaxine showed the lowest dissipation kinetics and the longest half-lives (250 to approximately 500 days) among the stable compounds. The highest first and second-order kinetics were, however, recorded for valsartan (k1; 0.262 day-1) and atorvastatin (k2; 33.8 g μg-1 day-1) respectively. Nevertheless, more than 90% (i.e., DT90) of all the rapidly dissipated compounds (i.e., atorvastatin, bisphenol S, and valsartan) disappeared from the tested soils within a short timescale (i.e., 5-36 days). Dissipation of pollutants that are more susceptible to microbial degradation (e.g., atorvastatin, bisphenol S, and valsartan) seems to be slower for soils possessing the lowest microbial biomass C (Cmic) and total phospholipid fatty acids (PLFAtotal), which also found statistically significant. Our results revealing the persistence of several organic pollutants in agricultural soils, which might impact the quality of these soils, the groundwater, and eventually on the related biota, is of high environmental significance.

Simultaneous determination of fourteen pharmaceuticals in sewage sludge using online solid-phase extraction-liquid chromatography-tandem mass spectrometry combined with accelerated solvent extraction

An online solid-phase extraction (SPE) liquid chromatography tandem mass spectrometry method (HPLC-MS/MS) combined with accelerated solvent extraction (ASE) was developed for simultaneous determination of 14 pharmaceuticals in sludge. In the online SPE procedures, ultrapure water with no additives was used as the loading solvent. In addition, low molecular weight targets such as atenolol were difficult to retain on SPE column after acetone was added to the washing solvent. The response signal of analytes can be greatly improved by adding 0.2% formic acid to the mobile phase. Under the optimized conditions, the recoveries of all the analytes ranged between 75.1 and 112%. Moreover, the limit of detections ranged from 1.8 to 7.9 ug/kg. The precision of analytical data was determined with relative standard deviation (RSD) ≤ 4.87%. This method was successfully applied to determine the concentration of pharmaceuticals in sludge.

Pharmaceutical pollution of hospital effluents and municipal wastewaters of Eastern Canada

Quantification of drugs residues in wastewaters of different sources could help better understand contamination pathways, eventually leading to effluent regulation. However, limited data are available for hospital-derived wastewaters. Here, an analytical method based on automated on-line solid-phase extraction liquid chromatography tandem mass spectrometry (on-line SPE - UPLC-MS/MS) was developed for the quantification of multi-class pharmaceuticals in wastewaters. Filtrate phase and suspended solids (SPM) were both considered to evaluate the distribution of targeted analytes. Experimental design optimization involved testing different chromatographic columns, on-line SPE columns, and loading conditions for the filtrate phase, and different organic solvents and cleanup strategies for suspended solids. The selected methods were validated with suitable limits of detection, recovery, accuracy, and precision. A total of 30 hospital effluents and 6 wastewater treatment plants were sampled to evaluate concentrations in real field-collected samples. Certain pharmaceuticals were quantified at high levels such as caffeine at 670,000 ng/L in hospital wastewaters and hydroxyibuprofen at 49,000 ng/L in WWTP influents. SPM samples also had high contaminant concentrations such as ibuprofen at 31,000 ng/g in hospital effluents, fluoxetine at 529 ng/g in WWTP influents or clarithromycin at 295 ng/g in WWTP effluents. Distribution coefficients (K_d) and particle-associated fractions (Φ) indicate that pharmaceuticals tend to have better affinity to suspended solids in hospital wastewater than in municipal wastewaters. The results also bring arguments for at source treatment of these specific effluents before their introduction into urban wastewater systems.

Determination of antimicrobial agents and their transformation products in an agricultural water-soil system modified with manure

Manure fertilization is the primary source of veterinary antimicrobials in the water-soil system. The research gap is the fate of antimicrobials after their release into the environment. This study aimed to provide a detailed and multi-faceted examination of fertilized cultivated fields using two types of manure (poultry and bovine) enriched with selected antimicrobials. The research focused on assessing the mobility and stability of antimicrobials in the water-soil system. Additionally, transformation products of antimicrobials in the environment were identified. The extraction (solid-phase extraction and/or solid-liquid extraction) and LC-MS/MS analysis procedures were developed to determine 14 antimicrobials in the soil and pore water samples. Ten out of fourteen antimicrobials were detected in manure-amended soil and pore water samples. The highest concentration in the soil was 109.1 ng g^-1 (doxycycline), while in pore water, it was 186.6 ng L^-1 (ciprofloxacin). Sixteen transformation products of antimicrobials were identified in the soil and soil-related pore water. The same transformation products were detected in both soil and soil pore water extracts, with significantly higher signal intensities observed in soil extracts than in water. Transformation products were formed in oxidation, carbonylation, and ring-opening reactions.

Biomarker responses and metabolism in Lumbricus terrestris exposed to drugs of environmental concern, an in vivo and in vitro approach

The earthworm Lumbricus terrestris is an anecic species living in natural soils but it is also a sentinel in pollution monitoring. Specimens of L.terrestris were exposed for 48 h though the filter paper contact test at 1 mg/mL of the chemicals: Lamotrigine (LMG), Cocaine (COC), Fipronil (FIP) and the pesticide bis-4-nitrophenyl phosphate (BNPP). After that period, the activities of Acetylcholinesterase, Glutathione S-transferase, Carboxylesterase (CE) using different substrates, and lipid peroxidation levels were evaluated in the exposed whole tissue earthworms. The results revealed differences only in CE activity, with 4-nitrophenyl butyrate (4NPB) and 1-naphthyl butyrate (1NB) the most responsive substrates to COC. The kinetic parameters of CE were characterized, for the first time, in whole tissue of this species. The chemical analysis by LC-MS/MS, confirmed the exposure to the parent compounds, identified metabolites and evidenced biotransformation pathways in earthworms. Metabolic reactions included oxidation (LMG and FIP), hydrolysis (COC and FIP) as well as glycosylation (LMG, COC and FIP). A hitherto unknown metabolite of LMG due to the conjugation with phenylalanine glutamine was formed. The in vivo results on CE activity with the specific inhibitor, BNPP, were confirmed in vitro. Moreover, in the in vitro approach, the inclusion of other contaminants of environmental concern supports the potential of CE as biomarker. This study identifies the main metabolites formed by earthworms for further in vivo exposures under more realistic conditions and the potential use of CE measures as biomarker of emerging contaminants.

Treated Wastewater Irrigation—A Review

As the most important resource for life, water has been a central issue on the international agenda for several decades. Yet, the world’s supply of clean freshwater is steadily decreasing due to extensive agricultural demand for irrigated lands. Therefore, water resources should be used with greater efficiency, and the use of non-traditional water resources, such as Treated Wastewater (TW), should be increased. Reusing TW could be an alternative option to increase water resources. Thus, many countries have decided to turn wastewater into an irrigation resource to help meet urban demand and address water shortages. However, because of the nature of that water, there are potential problems associated with its use in irrigation. Some of the major concerns are health hazards, salinity build-up, and toxicity hazards. The objectives of this comprehensive literature review are to illuminate the importance of using TW in irrigation as an alternative freshwater source and to assess the effects of its use on soil fertility and other soil properties, plants, and public health. The literature review reveals that TW reuse has become part of the extension program for boosting water resource utilization. However, the uncontrolled application of such waters has many unfavorable effects on both soils and plants, especially in the long-term. To reduce these unfavorable effects when using TW in irrigation, proper guidelines for wastewater reuse and management should be followed to limit negative effects significantly.

Comparison of high resolution mrm and sequential window acquisition of all theoretical fragment-ion acquisition modes for the quantitation of 48 wastewater-borne pollutants in lettuce

Screening of a large number of chemicals of emerging concern is highly desirable for the control of crops irrigated with reclaimed water since it is considered an alternative water source of great value. This study describes a high resolution mass spectrometry approach for developing methods for quantification in lettuce leaves of 48 different wastewater-borne pollutants (including analgesics and anti-inflammatories, anti-hypertensives, antifungal agents, lipid regulators, psychiatric drugs and stimulants, β-blockers, antibiotics, antimycotics, and sweeteners) frequently found in water resources. In this respect, a simple and fast QuEChERS-based method for the determination of contaminants in lettuce has been developed. During extraction, the use of formic acid was adopted to further improve the results of some problematic compounds (e.g., fenofibrate, furosemide, metronidazole, oxcarbazepine, sulfanilamide). High resolution multiple reaction monitoring (MRMHR) and SWATH acquisition were compared in term of accuracy, repeatability, sensitivity, linearity and matrix effect. Both methods provided similar recoveries between 80 and 120% in lettuce leaves, although sulfanilamide, ciprofloxacin, and sulfamethazine presenting values of 26.8, 27.8, and 28.4% in MRMHR and 25, 33.9, and 35% in SWATH, respectively. The effectiveness of a two-step cleanup on analyte recovery was also assessed and matrix effects were also taken into consideration during the method validation. The developed method allows the simultaneous quantitative analysis of 48 compounds (drug residues and metabolites) in lettuce leaves irrigated with treated wastewater for human consumption. Application of the present method to lettuce crops growth in controlled conditions showed the presence of 14 out 48 studied compounds with similar concentrations in both acquisition modes ranging from 3.3 and 1.3 ng g - 1 for climbazole (for MRMHR and SWATH, respectively) to 33.2 and 17.7 ng g - 1 for sulfamethazine. Drug residues such as carbamazepine (6.0 and 8.5 ng g - 1), and its metabolite carbamazepine epoxide (18.1 and 16.5 ng g - 1), frequently found in wastewater effluents, were also detected.

Local Phenomena Shape Backyard Soil Metabolite Composition

Soil covers most of Earth's continental surface and is fundamental to life-sustaining processes such as agriculture. Given its rich biodiversity, soil is also a major source for natural product drug discovery from soil microorganisms. However, the study of the soil small molecule profile has been challenging due to the complexity and heterogeneity of this matrix. In this study, we implemented high-resolution liquid chromatography-tandem mass spectrometry and large-scale data analysis tools such as molecular networking to characterize the relative contributions of city, state and regional processes on backyard soil metabolite composition, in 188 soil samples collected from 14 USA States, representing five USA climate regions. We observed that region, state and city of collection all influence the overall soil metabolite profile. However, many metabolites were only detected in unique sites, indicating that uniquely local phenomena also influence the backyard soil environment, with both human-derived and naturally-produced (plant-derived, microbially-derived) metabolites identified. Overall, these findings are helping to define the processes that shape the backyard soil metabolite composition, while also highlighting the need for expanded metabolomic studies of this complex environment.