Validation and uncertainties evaluation of an isotope dilution-SPE-LC–MS/MS for the quantification of drug residues in surface waters

Monitoring Pharmaceuticals and Personal Care Products in Drinking Water Samples by the LC-MS/MS Method to Estimate Their Potential Health Risk

(1) The occurrence and accumulation of pharmaceuticals and personal care products in the environment are recognized scientific concerns. Many of these compounds are disposed of in an unchanged or metabolized form through sewage systems and wastewater treatment plants (WWTP). WWTP processes do not completely eliminate all active substances or their metabolites. Therefore, they systematically leach into the water system and are increasingly contaminating ground, surface, and drinking water, representing a health risk largely ignored by legislative bodies. Especially during the COVID-19 pandemic, a significantly larger amount of medicines and protective products were consumed. It is therefore likely that contamination of water sources has increased, and in the case of groundwater with a delayed effect. As a result, it is necessary to develop an accurate, rapid, and easily available method applicable to routine screening analyses of potable water to monitor and estimate their potential health risk. (2) A multi-residue UHPLC-MS/MS analytical method designed for the identification of 52 pharmaceutical products was developed and used to monitor their presence in drinking water. (3) The optimized method achieved good validation parameters, with recovery of 70-120% of most analytes and repeatability achieving results within 20%. In real samples of drinking water, at least one analyte above the limit of determination was detected in each of the 15 tap water and groundwater samples analyzed. (4) These findings highlight the need for legislation to address pharmaceutical contamination in the environment.

A review of pharmaceutical occurrence and pathways in the aquatic environment in the context of a changing climate and the COVID-19 pandemic

Active pharmaceutical ingredients (APIs) are increasingly being identified as contaminants of emerging concern (CECs). They have potentially detrimental ecological and human health impacts but most are not currently subject to environmental regulation. Addressing the life cycle of these pharmaceuticals plays a significant role in identifying the potential sources and understanding the environmental impact that pharmaceuticals may have in surface waters. The stability and biological activity of these "micro-pollutants" can lead to a pseudo persistence, with ensuing unknown chronic behavioural and health-related effects. Research that investigates pharmaceuticals predominantly focuses on their occurrence and effect within surface water environments. However, this review will help to collate this information with factors that affect their environmental concentration. This review focuses on six pharmaceuticals (clarithromycin, ciprofloxacin, sulfamethoxazole, venlafaxine, gemfibrozil and diclofenac), chosen because they are heavily consumed globally, have poor removal rates in conventional activated sludge wastewater treatment plants (CAS WWTPs), and are persistent in the aquatic environment. Furthermore, these pharmaceuticals are included in numerous published prioritisation studies and/or are on the Water Framework Directive (WFD) "Watch List" or are candidates for the updated Watch List (WL). This review investigates the concentrations seen in European Union (EU) surface waters and examines factors that influence final concentrations prior to release, thus giving a holistic overview on the source of pharmaceutical surface water pollution. A period of 10 years is covered by this review, which includes research from 2009-2020 examining over 100 published studies, and highlighting that pharmaceuticals can pose a severe risk to surface water environments, with each stage of the lifecycle of the pharmaceutical determining its concentration. This review additionally highlights the necessity to improve education surrounding appropriate use, disposal and waste management of pharmaceuticals, while implementing a source directed and end of pipe approach to reduce pharmaceutical occurrence in surface waters.

Interpol review of controlled substances 2016-2019

This review paper covers the forensic-relevant literature in controlled substances from 2016 to 2019 as a part of the 19th Interpol International Forensic Science Managers Symposium. The review papers are also available at the Interpol website at: https://www.interpol.int/content/download/14458/file/Interpol%20Review%20Papers%202019.pdf.

Soil influences on uptake and transfer of pharmaceuticals from sewage sludge amended soils to spinach

Sewage sludge from wastewater treatment plants, which may contain various contaminants including pharmaceuticals, is often used as a soil amendment. These contaminants may subsequently be taken up by plants. In the present study we examined uptake of select pharmaceuticals from sewage sludge applied to soils by spinach plants. Seven soils were amended with sewage sludge from two wastewater treatment plants (A and B). Concentrations of compounds in plant tissues (roots and leaves) of spinach planted 45 days in these soils under greenhouse conditions were evaluated after harvest. The largest bioaccumulation in the roots and leaves was observed for sertraline (bioaccumulation factors (BAF) of 3.3-37.9 and 1-13.4, respectively), tramadol (1.3-10.0 and 4.8-30.0), and carbamazepine (2.2-17.2 and 6.1-48.8) and its metabolite carbamazepine 10,11-epoxide (not-quantified to 7.3 and 9.3-96.7). Elevated bioaccumulation in spinach roots was also identified for telmisartan (3.0-20.3) and miconazole (4.3-15.1), and leaves for metoprolol acid (not-quantified to 24.3). BAF values resulting from application of sludge B were similar to or moderately higher than BAFs from sludge A. The BAF values of carbamazepine and carbamazepine 10,11-epoxide in all tissues were negatively correlated with soil cation exchange capacity (CEC). This negative correlation between BAF and CEC was also observed for tramadol (A-roots and B-leaves), citalopram (B-roots), and telmisartan (B-roots) or between BAF and clay content for metoprolol acid (A-leaves and B-roots), tramadol (B-roots and A-leaves) and venlafaxine (B-roots). However, in the case of some other compounds (i.e. sertraline, amitriptyline, mirtazapine, metoprolol), uptake and the subsequent translocation and transformation from 3 soils of a higher pH and base cation saturation (Stagnic Chernozem Siltic, Haplic Chernozem and Greyic Phaeozem) significantly differed from 4 soils with a lower pH and base cation saturation (Haplic Luvisol, Haplic Cambisol, Dystric Cambisol and Arenosol Epieutric). Such observations proved strong compound dependent influences of soil conditions on various compounds bioaccumulations in plants and necessity of studying these processes always in diverse soils.

Development and Validation of an Analytical Method for the Detection and Quantification of Bromazepam, Clonazepam and Diazepam by UPLC-MS/MS in Surface Water

The development of analytical methods capable of determining micropollutants is essential for quality control of drinking water. Benzodiazepines, a class of pharmaceuticals with anxiolytic properties, have received increasing attention as micropollutants. The purpose of this study was to develop an analytical method for determination of three benzodiazepine drugs (bromazepam, clonazepam and diazepam) in surface water. For the extraction of the matrix analytes, SPE cartridges (C18, 500 mg/3 mL) were used. The method was validated according to the quality criteria of the USEPA 8000D Validation Guide. The developed and validated method showed recovery values between 57 and 100%, RSD < 20% and R² > 0.9949. LD ranged between 2.70 and 5.00 ng L^-1 for bromazepam and clonazepam respectively whereas LQ was 0.01 μg L^-1 for all analytes. The matrix affected the signal intensity of clonazepam thus evidencing the matrix effect by analysis statistic (F test).

Acidic transformation of nordiazepam can affect recovery estimate during trace analysis of diazepam and nordiazepam in environmental water samples by liquid chromatography-tandem mass spectrometry

In this study, a special interest was focused on the stability of diazepam and nordiazepam in aqueous samples at acidic and neutral pH. The aim of the study was to isolate and illustrate one of the many possible sources of error that can be encountered when developing and validating analytical methods. This can be of particular importance when developing multi-analyte methods where there is limited time to scrutinize the behavior of each analyte. A method was developed for the analysis of the benzodiazepines diazepam and nordiazepam in treated wastewater. The samples were extracted by solid phase extraction, using SPEC C18AR cartridges, and analyzed by the use of liquid chromatography, with a C18 stationary phase, coupled to tandem mass spectrometry. Environmental water samples are often acidified during storage to reduce the microbial degradation of the target compounds and to preserve the sample. In some cases, the samples are acidified before extraction. In this study, it was found that a chemical equilibrium between nordiazepam and a transformation product could cause inaccurately high extraction recovery values when the samples were stored at low sample pH. The stability of nordiazepam was shown to be low at pH 3. Within 12 days, 20% of the initial concentration of nordiazepam was transformed. Interestingly, the transformed nordiazepam was shown to be regenerated and reformed to nordiazepam during sample handling. At a sample pH of 7, diazepam and nordiazepam were stable for 12 days. It was concluded that great care must be taken when acidifying water samples containing nordiazepam during storage or extraction. The storage and the extraction should be conducted at neutral pH if no internal standard is used to compensate for degradation and conversion of nordiazepam. The developed method was validated in treated wastewater and applied for the quantification of diazepam and nordiazepam in treated wastewater samples.

Pharmaceuticals in freshwater aquatic environments: A comparison of the African and European challenge

Hundreds of tons of pharmaceutical compounds are annually dispensed and consumed worldwide. Pharmaceuticals are an important class of emerging environmental micropollutants: their presence in water bodies is an increasing environmental concern. The aim of this review paper is to provide a comprehensive review of the occurrence of pharmaceuticals in freshwater aquatic environments in the African and European context. A literature survey has been performed, resulting in 3024 data points related to environmental occurrence. The concentration levels of 71 pharmaceuticals were assessed. The top ten most frequently detected and quantified compounds in both continents were sulfamethoxazole, carbamazepine, diclofenac, trimethoprim, ibuprofen, naproxen, paracetamol (acetaminophen), ketoprofen, venlafaxine and clarithromycin. The maximum concentrations of 17β-estradiol, estriol, ciprofloxacin, sulfamethoxazole, paracetamol, naproxen reported in African aquatic environments were ~3140, ~20,000, ~125, ~100, ~215 and ~171 times higher, respectively, than the concentrations reported in European based studies. The variation in pharmaceutical consumption, partial removal of pharmaceuticals in wastewater treatment processes, and the direct discharge of livestock animal farm wastewater were identified among the major reasons for the observed differences. Several pharmaceuticals were found in aquatic environments of both continents in concentration levels higher than their ecotoxicity endpoints. In Europe, compounds such as diclofenac, ibuprofen, triclosan, sulfadimidine, carbamazepine and fluoxetine were reported in a concentration higher than the available ecotoxicity endpoints. In Africa, much more compounds reached concentrations more than the ecotoxicity endpoints, including diclofenac, ibuprofen, paracetamol, naproxen, ciprofloxacin, triclosan, trimethoprim, sulfamethoxazole, carbamazepine and fluoxetine, estriol and 17β-estradiol. Details for each therapeutic group are presented in this review.

Validation of a method to monitor the occurrence of 20 relevant pharmaceuticals and personal care products in 167 bottled waters

Research on emerging substances in drinking water presents major interest and the possibility of trace contamination has seen increasing concern from the scientific community and the public authorities. More particularly, residues of pharmaceuticals and personal care products (PPCPs) in bottled water are a very important issue due to societal concerns and potential media impact. In this context, it has become necessary to carry out reliable monitoring. This requires measurements of high quality with demonstration of accuracy and well-defined uncertainty. In this study, 20 pharmaceutical compounds were targeted for the first time in 167 bottled waters from France and other European countries. An isotope dilution-solid phase extraction-liquid chromatography mass spectrometry method, together with stringent quality control and quality assurance protocols, was developed and validated according to French mandatory standards. Recoveries between 87% and 112% were obtained with coefficient of variation below 20%. Operational limits of quantification (LOQ) were comprised between 5 and 30ngL^-1. Expanded uncertainties (k=2) ranged between 16% and 43% and were below 35% for half of the compounds. The survey showed only four positive quantifications, thereby highlighting the rarity of contamination.