Analysis of emerging organic contaminants in environmental solid samples

Spreading sewage sludge on agricultural lands has been actively promoted by national authorities as an economic way of recycling. However, as by-product of wastewater treatment, sewage sludge may contain toxic substances, which could be incorporated into agricultural products or be distributed in the environment. Moreover, sediments can be contaminated by the discharge of wastewater effluents into rivers. This article reviews the determination of emerging contaminants (surfactants, flame retardants, pharmaceuticals and personal care products) in environmental solid samples (sludge, soil and sediment). Sample preparation, including extraction and clean-up, as well as the subsequent instrumental determination of contaminants are discussed. Recent applications of extraction techniques, such as Soxhlet extraction, ultrasound assisted extraction, pressurised liquid extraction, microwave assisted extraction and matrix solid-phase dispersion to the analysis of emerging contaminants in environmental solid samples are reviewed. Determination of these contaminants, generally carried out by gas chromatography and liquid chromatography coupled with different detectors, especially mass spectrometry for the identification and quantification of residues, is also summarised and discussed.      

Environmental risk assessment of pharmaceutical residues in wastewater effluents, surface waters and sediments

Pharmaceutical residues in the environment, and their potential toxic effects, have been recognized as one of the emerging research area in the environmental chemistry. The increasing attention, on pharmaceutical residues as potential pollutants, is due that they often have similar physico-chemical behaviour than other harmful xenobiotics which are persistent or produce adverse effects. In addition, by contrast with regulated pollutants, which often have longer environmental half-lives, its continuous introduction in the environment may make them “pseudopersistents”.Pharmaceutical residues and/or their metabolites are usually detected in the environment at trace levels, but, even that, low concentration levels (ng/L or μg/L) can induce to toxic effects. In particular, this is the case of antibiotics and steroids that cause resistance in natural bacterial populations or endocrine disruption effects.In this study, an overview of the environmental occurrence and ecological risk assessment of pharmaceutical residues is presented from literature data. Risk Quotient method (RQ) was applied as a novel approach to estimate the environmental risk of pharmaceuticals that are most frequently detected in wastewater effluents, surface waters and sediments.     

Pharmaceuticals and personal care products in biosolids/sewage sludge: the interface between analytical chemistry and regulation

Modern sanitary practices result in large volumes of human waste, as well as domestic and industrial sewage, being collected and treated at common collection points, wastewater treatment plants (WWTPs). In recognition of the growing use of sewage sludge as fertilizers and soil amendments, and the scarcity of current data regarding the chemical constituents in sewage sludge, the US National Research Council (NRC) in 2002 produced a report on sewage sludge. Among the NRC’s recommendations was the need for investigating the occurrence of pharmaceuticals and personal care products (PPCPs) in sewage sludge. PPCPs are a diverse array of non-regulated contaminants that had not been studied in previous sewage sludge surveys but which are likely to be present. The focus of this paper will be to review the current analytical methodologies available for investigating whether pharmaceuticals are present in WWTP-produced sewage sludge, to summarize current regulatory practices regarding sewage sludge, and to report on the presence of pharmaceuticals in sewage sludge.     

Occurrence patterns of pharmaceuticals in water and wastewater environments

The occurrence of pharmaceuticals and their metabolites and transformation products in the environment is becoming a matter of concern, because these compounds, which may have adverse effects on living organisms, are extensively and increasingly used in human and veterinary medicine and are released continuously into the environment. A variety of pharmaceuticals have been detected in many environmental samples worldwide. Their occurrence has been reported in sewage-treatment-plant effluents, surface water, seawater, groundwater, soil, sediment and fish. This paper provides an overview of recent scientific research on the sources, occurrence, and fate of pharmaceuticals in water and wastewater.     

Human and environmental risk assessment of pharmaceuticals: differences,similarities, lessons from toxicology

The presence of human and veterinary pharmaceuticals in the environment has caused increasing concern due their effects on ecological receptors. Improving the risk assessment of these compounds necessitates a quantitative understanding of their metabolism and elimination in the target organism (toxicokinetics), particularly via the ubiquitous cytochrome P-450 (CYP) system and their mechanisms of toxicity (toxicodynamics). This review focuses on a number of pharmaceuticals and veterinary medicines of environmental concern, and the differences and similarities between ecological and human risk assessment. CYP metabolism is discussed with particular reference to its ubiquity in species of ecological relevance. The important issue of pharmaceutical mixtures is discussed to assess how emerging technologies such as ecotoxicogenomics may assist in moving towards a more mechanism-based environmental risk assessment of pharmaceuticals.     

Holistic visualisation of the multimodal transport and fate of twelve pharmaceuticals in biosolid enriched topsoils

The use of municipal biosolids as agricultural fertilisers has raised significant concerns in recent years. As part of this, the presence of complex mixtures of pharmaceutical residues and their effects on soil ecosystems remains particularly under-researched. This study focuses on the transfer of a selection of pharmaceutical residues from municipal sewage sludge to agricultural topsoils and their fate therein after an accelerated 6-month rainfall event. Twelve pharmaceuticals encompassing antibiotics, analgesics, anti-inflammatories, beta-blockers, hyperlipidaemics and stimulants were invesigated by employing a combination of extraction techniques and liquid chromatography-tandem mass spectrometry. Both liquid- and solid-phase pharmaceutical contents were analysed and pharmaceutical and personal care products quantified at defined timepoints to elucidate transport behaviour and transformation potential. Results show the distribution and separation of pharmaceuticals over a 100-mm soil depth following typical biosolid enrichment. Using experimentally determined solid–water partition coefficients (K _d) and hydrophobicity distribution ratios (D _ow), mobility and modes of interaction under dynamic conditions are discussed. Finally, a brief study into the susceptibility of soil microbes is also presented. To our knowledge, this is the first investigation of pharmaceutical and personal care products release from amended biosolids to soils to include the factors and mechanisms governing their distribution and transformation even over relatively shallow depths. It applies multicompartmental and mass-balanced chemical analyses as well as microbiological approaches for a holistic view of these complex processes.      

Environmental application of gamma technology: Update on the Canadian sludge irradiator

Waste treatment and disposal technologies have recently been subjected to increasing public and regulatory scrutiny. Concern for the environment and a heightened awareness of potential health hazards that could result from insufficient or inappropriate waste handling methods have combined to push waste generators in their search for new treatment alternatives. Gamma technology can offer a new option for the treatment of potentially infectious wastes, including municipal sewage sludge.

Sewage sludge contains beneficial plant nutrients and a high organic component that make it ideal as a soil conditioning agent or fertilizer bulking material. It also carries potentially infectious microorganisms which limit opportunities for beneficial recycling of sludges. Gamma irradiation-disinfection of these sludges offers a reliable, fast and efficient method for safe sludge recycling.

Nordion International's Market Development Division was created in 1987 as part of a broad corporate reorganization. It was given an exclusive mandate to develop new applications of gamma irradiation technology and markets for these new applications. Nordion has since explored and developed opportunities in food irradiation, pharmaceutical/cosmetic products irradiation, biomedical waste sterilization, airline waste disinfection, and sludge disinfection for recycling. This paper focuses on the last of these -a proposed sludge recycling facility that incorporates a cobalt 60 sludge irradiator.     

Mass spectrometry for identifying pharmaceutical biotransformation products in the environment

Many classes of pharmaceuticals have been detected in wastewaters and surface waters around Europe, but little is known about their occurrence, fate and potential harmful effects on the environment, and that makes them an important group among those compounds considered to be new emerging contaminants. To understand the cycling of pharmaceuticals and their metabolites, it is essential to possess qualitative and quantitative information on their presence in the environment. This review covers the current status and future prospects of advanced hyphenated mass spectrometric (MS) techniques (gas chromatography-MS (GC-MS) and liquid chromatography-MS (LC-MS)) in elucidating the structures of trace contaminants, namely pharmaceutical biodegradation products in complex environmental matrices. The article is oriented towards technique and method and discusses capabilities, potential and limitations of different GC and LC mass analyzers (quadrupole, ion trap, time-of-flight and hybrid techniques) in dealing with analytical challenges of complex matrices and trace contaminants. We also give practical examples of their applications. The main scope of this article is to support and to facilitate the on-going research on pharmaceutical biodegradation products in environmental samples.     

Plant cell culture technologies: A promising alternatives to produce high-value secondary metabolites

Plants have been used for its medicinal values since ancient time. The medicinal properties of plants are based on their phytochemical constituent particularly secondary metabolites which are produced in low amounts by plants. Secondary metabolites have been used as medicines, flavors, colors, and fragrances. In recent time, these natural compounds are gaining enormous attention in pharmaceutical, cosmetics, and nutraceutical industries and are regarded economically valuable products. The production of plant secondary metabolites in plant is largely dependent on the plant species, environmental factors and geographical regions. In addition, the main challenges in their mass production is reported to be the quality and quantity issues during their synthesis. Therefore, enthusiasm has grown for increasing the production of secondary metabolites by employing in vitro plant cell culture technology and bioengineering methods. Such technological advancement, has led to production of a huge number of medicinal herbs and high-value secondary metabolites that are mostly used in pharmaceuticals, cosmetics and nutraceuticals industries. The current mini-review article focuses on applications of plant cell culture system for the production secondary metabolites and recent techniques used to improve metabolite contents. Furthermore, our review emphasizes safety issues of plant cell culture derived products.     

Pharmaceutical residues in environmental waters and wastewater: current state of knowledge and future research

Pollution from pharmaceuticals in the aquatic environment is now recognized as an environmental concern in many countries. This has led to the creation of an extensive area of research, including among others: their chemical identification and quantification; elucidation of transformation pathways when present in wastewater-treatment plants or in environmental matrices; assessment of their potential biological effects; and development and application of advanced treatment processes for their removal and/or mineralization. Pharmaceuticals are a unique category of pollutants, because of their special characteristics, and their behavior and fate cannot be simulated with other chemical organic contaminants. Over the last decade the scientific community has embraced research in this specific field and the outcome has been immense. This was facilitated by advances in chromatographic techniques and relevant biological assays. Despite this, a number of unanswered questions exist and still there is much room for development and work towards a more solid understanding of the actual consequences of the release of pharmaceuticals in the environment. This review tries to present part of the knowledge that is currently available with regard to the occurrence of pharmaceutical residues in aquatic matrices, the progress made during the last several years on identification of such compounds down to trace levels, and of new, previously unidentified, pharmaceuticals such as illicit drugs, metabolites, and photo-products. It also tries to discuss the main recent findings in respect of the capacity of various treatment technologies to remove these contaminants and to highlight some of the adverse effects that may be related to their ubiquitous existence. Finally, socioeconomic measures that may be able to hinder the introduction of such compounds into the environment are briefly discussed.     

Advantages of online SPE coupled with UPLC/MS/MS for determining the fate of pesticides and pharmaceutical compounds

Laboratory experimentation is essential for our understanding of the fate and behaviour of pollutants. Many analytical techniques exist, but they all have disadvantages either in terms of sensitivity or of selectivity. The number of samples that can be analysed, the low volume of samples available during the experiment and the need to identify different degradates are all obstacles that new techniques are able to overcome. The work presented here summarizes progress in the field of metrology as concerns online solid phase extraction technology coupled with liquid chromatography followed by tandem mass spectrometry detection. Recently developed analytical techniques were validated for both 18 pesticides and their degradates and 17 pharmaceuticals and their degradates. Limits of quantification from 20 to 70 ng L^?1 for pharmaceuticals and from 15 to 25 ng L^?1 for pesticides and metabolites have been obtained, with linearity range up to 1 μg L^?1. The limits of quantification of a few nanograms per litre, the possibility of working on less than 1 mL of sample and the simultaneous quantification of the target products and their transformation products are all advantages that are demonstrated by two environmental applications. The first application concerns the evaluation of ecotoxicological effects of pesticides on aquatic organisms exposed in mesocosms. The second application aims to determine the adsorption constants of pharmaceutical molecules on soils and river sediments. For both applications, the robustness, range of linearity and limit of quantification of the developed analytical methods satisfy the requirements for laboratory experiments conducted under controlled conditions. Specific constraints generated by this type of experiment (adding CaCl₂ for the adsorption study and filtration of the water coming from the mesocosms) were not found to limit the use of online SPE. These two preliminary studies show that new experimental fields are possible thanks to online solid phase extraction coupled with liquid chromatography.     

Pharmaceuticals in biota in the aquatic environment: analytical methods and environmental implications

The presence of pharmaceuticals in the aquatic environment is an ever-increasing issue of concern as they are specifically designed to target specific metabolic and molecular pathways in organisms, and they may have the potential for unintended effects on nontarget species. Information on the presence of pharmaceuticals in biota is still scarce, but the scientific literature on the subject has established the possibility of bioaccumulation in exposed aquatic organisms through other environmental compartments. However, few studies have correlated both bioaccumulation of pharmaceutical compounds and the consequent effects. Analytical methodology to detect pharmaceuticals at trace quantities in biota has advanced significantly in the last few years. Nonetheless, there are still unresolved analytical challenges associated with the complexity of biological matrices, which require exhaustive extraction and purification steps, and highly sensitive and selective detection techniques. This review presents the trends in the analysis of pharmaceuticals in aquatic organisms in the last decade, recent data about the occurrence of these compounds in natural biota, and the environmental implications that chronic exposure could have on aquatic wildlife.     

Analytical methods for the determination of fluoroquinolones in solid environmental matrices

We present a critical review of the analytical procedures proposed in the past decade for the determination of fluoroquinolones (FQs) by chromatographic methods in solid environmental matrices. We emphasize the overall analytical procedure, from sampling to final detection. We devote special attention to sample preparation, highlighting the problems involved in the analysis of real complex matrices, mainly soil, sediment, manure and sludge. We compare the different extraction techniques in terms of efficiency, time taken and environmental impact, pointing out advantages and drawbacks. We provide an overview on the role of photochemistry in the degradation of FQs in soils and sediments, and we underline the central position of analytical chemistry in environmental monitoring because FQs are emerging pollutants.     

Influence of Organic Matter on the Sorption of Cefdinir,Memantine and Praziquantel on Different Soil and Sediment Samples

Pharmaceuticals are known for their great effects and applications in the treatment and suppression of various diseases in human and veterinary medicine. The development and modernization of science and technologies have led to a constant increase in the production and consumption of various classes of pharmaceuticals, so they pose a threat to the environment, which can be subjected to the sorption process on the solid phase. The efficiency of sorption is determined by various parameters, of which the physicochemical properties of the compound and the sorbent are very important. One of these parameters that determine pharmaceutical mobility in soil or sediment is the soil–water partition coefficient normalized to organic carbon (K_oc), whose determination was the purpose of this study. The influence of organic matter, suspended in an aqueous solution of pharmaceutical (more precisely: cefdinir, memantine, and praziquantel), was studied for five different types of soil and sediment samples from Croatia. The linear, Freundlich, and Dubinin–Raduskevich sorption isotherms were used to determine specific constants such as the partition coefficient K_d, which directly describes the strength of sorbate and sorbent binding. The linear model proved to be the best with the highest correlation coefficients, R² > 0.99. For all three pharmaceuticals, a positive correlation between sorption affinity described by K_d and K_oc and the amount of organic matter was demonstrated.     

Liquid chromatography-tandem mass spectrometry for the analysis of pharmaceutical residues in environmental samples: a review

Pharmaceutical residues are environmental contaminants of recent concern and the requirements for analytical methods are mainly dictated by low concentrations found in aqueous and solid environmental samples. In the current article, a review of the liquid chromatography-tandem mass spectrometry (LC-MS/MS) based methods published so far for the determination of pharmaceuticals in the environment is presented. Pharmaceuticals included in this review are antibiotics, non-steroidal anti-inflammatory drugs, beta-blockers, lipid regulating agents and psychiatric drugs. Advanced aspects of current LC-MS/MS methodology, including sample preparation and matrix effects, are discussed.     

Determination of alkylphenol ethoxylates in industrial and environmental samples

Degradation products of nonionic surfactants, which are used in large quantities in several industrial applications, have been shown to elicit estrogenic effects in the laboratory as well as in the environment. This has prompted the monitoring of such products, in particular the alkylphenols (AP) and alkylphenol ethoxylates (APE), in the environment. This study presents a relatively simple method for the determination of AP and APE in industrial and environmental samples by HPLC and GC-MS. It discusses some of the inherent analytical issues concomitant with the determination of the complicated mixtures these analytes are composed of. The method was applied to marine and estuarine sediments as well as wastewater and sewage sludge samples taken from industrial plants. In all marine and estuarine samples APE were found with a predominance of oligomers containing 1–3 ethoxylate units.     

Determination of pharmaceuticals in environmental and biological matrices using pressurised liquid extraction—Are we developing sound extraction methods?

Pressurised liquid extraction (PLE) is now a well established and extensively applied extraction technique in environmental analysis for pollutants such as persistent organic pollutants (POPs). During the past decade, an emerging group of environmentally interesting analytes are pharmaceuticals that are continuingly released into the environment. This class is comprised with compounds of various properties. As the field of the analysis of these compounds grows, an increasing number of PLE methods for pharmaceuticals of varying quality are developed and published. This review summarises the critical PLE parameters during PLE method development and highlight them with examples from recently published papers utilising pressurised liquid extraction for the determination of pharmaceuticals in environmental and biological matrices. These recent methods are summarised and critically discussed with the aim to provide important reflections to alleviate in future PLE development for pharmaceuticals in environmental matrices.     

Downstream Processing of Therapeutic Peptides by Means of Preparative Liquid Chromatography

The market of biomolecules with therapeutic scopes, including peptides, is continuously expanding. The interest towards this class of pharmaceuticals is stimulated by the broad range of bioactivities that peptides can trigger in the human body. The main production methods to obtain peptides are enzymatic hydrolysis, microbial fermentation, recombinant approach and, especially, chemical synthesis. None of these methods, however, produce exclusively the target product. Other species represent impurities that, for safety and pharmaceutical quality reasons, must be removed. The remarkable production volumes of peptide mixtures have generated a strong interest towards the purification procedures, particularly due to their relevant impact on the manufacturing costs. The purification method of choice is mainly preparative liquid chromatography, because of its flexibility, which allows one to choose case-by-case the experimental conditions that most suitably fit that particular purification problem. Different modes of chromatography that can cover almost every separation case are reviewed in this article. Additionally, an outlook to a very recent continuous chromatographic process (namely Multicolumn Countercurrent Solvent Gradient Purification, MCSGP) and future perspectives regarding purification strategies will be considered at the end of this review.     

Selected drugs in solid matrices: a review of environmental determination, occurrence and properties of principal substances

After intake, drugs absorbed by human or animal organisms are subject to metabolic reactions, such as hydroxylation, cleavage or glucuronation. However, a significant amount of the original or the metabolized substance leaves the organism via urine or feces. Thanks to improvements in analytical chemistry, many pharmaceutical compounds and endocrine disrupters are more easily detected in the surface-water and waste-water environmental compartments, at ppb concentrations.But what contaminates our solid environmental matrices? These substances can be eliminated by sorption or biodegradation but, at present, there is not enough data to allow evaluation of the behavior of the substances through the solid compartment, such as soil, sludge and bio-waste.This article provides an overview of the occurrence of pharmaceutical compounds in solid matrices on the basis of the quantities used, their physico-chemical properties and data from literature indicating the potential of the drug to persist in sediment, soil or sludge.