Vera Homem

Vera Homem
University of Porto | UP · Departamento de Engenharia Química

PhD Environmental Engineering

About

95
Publications
8,100
Reads
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2,396
Citations
Introduction
Her research has been mainly focused on the development, optimization and validation of analytical methods for the detection of emerging organic contaminants in trace levels in the environment, monitoring and remediation technologies and design of experiments. Currently, her research strategy also includes the development of environmental risk assessment studies (exposure and effects assessment, risk characterization), chemical scoring and prioritization systems.
Additional affiliations
June 2018 - present
University of Porto
Position
  • Research Associate
September 2015 - March 2016
University of Porto
Position
  • Invited Assistant Professor
September 2014 - March 2015
University of Porto
Position
  • Invited Assistant Professor
Education
December 2007 - November 2011
University of Porto
Field of study
  • Environmental Engineering
September 2002 - July 2007
University of Porto
Field of study
  • Chemical Engineering

Publications

Publications (95)
Article
Crumb rubber derived from end-of-life tires (ELTs) is frequently used as infill of synthetic turf pitches, promoting circular economy. Although important to reduce the accumulation of waste, the use of recycled ELTs can be a problem to human health and the environment, both by direct contact during pitch use and by the release of these elements to...
Article
Volatile methylsiloxanes (VMSs) are found in a broad range of industrial and consumer products. They are categorized as “high production volume chemicals” by the U.S. Environmental Protection Agency and listed as candidates of substances of very high concern in 2018, by the Registration, Evaluation, Authorization and Restriction of Chemicals (REACH...
Article
Although there are several works in the literature that study the presence of pharmaceuticals and personal care products (PPCPs) in surface waters, the vast majority focus their attention on pharmaceuticals and little information is found about personal care products (PCPs). Therefore, this study focused, for the first time, on the monitoring of fi...
Article
A headspace solid-phase microextraction (HS-SPME) method was developed using the metal-organic framework (MOF) CIM-80(Al) as extraction phase and in combination with gas chromatography-mass spectrometry (GC-MS) for the simultaneous determination of 6 methylsiloxanes and 7 musk fragrances in different environmental waters. The chromatographic separa...
Article
Full-text available
Volatile methylsiloxanes (VMSs) constitute a group of compounds used in a great variety of products, particularly personal care products. Due to their massive use, they are continually discharged into wastewater treatment plants and are increasingly being detected in wastewater and in the environment at low concentrations. The aim of this work was...
Article
A simple method for the analysis of thirteen synthetic musk compounds and six ultraviolet filters in soil samples was developed using a modified dispersive solid‐phase methodology known as “Quick, Easy, Cheap, Effective, Rugged and Safe”, followed by gas chromatography – triple quadrupole mass spectrometry (GC‐MS/MS). The methodology was validated...
Article
In the last years, the number of wastewater treatment plants (WWTPs) has increased and consequently, sewage sludge production. This residue is very rich in crop nutrients, which makes it prone to be used as organic fertilizer or soil conditioner for agriculture. However, the presence of emerging pollutants in these fertilizers has raised concern, n...
Article
Volatile methylsiloxanes are wastewater organic pollutants originating from industrial and personal care products. They accumulate in sewage sludge and hamper biogas production through the formation of silicon dioxide on the surfaces of gas engines and turbines, yet there is few knowledge on their fate in sludge treatment systems. Here we studied t...
Chapter
Silicon materials are widespread in our daily life and in numerous industrial applications, and this started raising concerns in the scientific community a couple of decades ago regarding the potential negative effects these chemicals could have in the environment and human health. Naturally, analytical methodologies were required to assess their p...
Article
Full-text available
Ethnopharmacological use of plant natural extracts has been known since ancient times. The optimization of plant molecule extraction is fundamental in obtaining relevant extraction yields. The main purpose of this study was to understand the role of different extraction techniques (solid-liquid, ultrasound, Soxhlet, and microwave) and solvents (wat...
Book
Comprising 12 chapters, this book focuses on volatile methylsiloxanes (VMSs), the shorter-chained organosiloxanes, and reviews the main areas and environmental compartments where they have been found and studied. It opens with a detailed description of the structural and functional properties, toxic risks and possible transformations of VMSs in the...
Chapter
This final chapter intends to convey to the readers the main lessons learned so far, the most important challenges found and an overview of the possible research trends yet to explore in the study of volatile methylsiloxanes (VMSs) in the environment. From all the excellent contributions to this book, besides a comprehensive and thorough display of...
Article
A Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) methodology followed by gas chromatography-tandem mass spectrometry (GC-MS/MS) analysis was developed to extract thirteen synthetic musk compounds (SMCs: cashmeran, celestolide, phantolide, traseolide, galaxolide, tonalide, musk ambrette, musk xylene, musk ketone, musk tibetene, musk moske...
Article
A methodology based on solid-phase microextraction (SPME) followed by gas chromatography-tandem mass spectrometry (GC-MS/MS) was developed for the simultaneous analysis of different families of personal care products (PCPs) including fragrance allergens, synthetic musks, phthalates, antioxidants and UV filters in continental waters. The main parame...
Article
Full-text available
Many persistent organic pollutants (POPs) have been banned in many countries including Argentina after enforcing the Stockholm Convention in 2014, while other emerging semi-volatile organic contaminants (SVOCs) are considered to enter the list due to their known environmental persistence and toxicity. However, there is still very little information...
Article
An analytical method was developed for the simultaneous analysis of 19 emergent compounds in water matrices, six UV-filters (UVFs), five nitro, six polycyclic and two macrocyclic musks. The target compounds were extracted by a dispersive liquid-liquid microextraction (DLLME) approach, using 2-propanol as the dispersive solvent and 1,1,2-trichloroet...
Article
This study focused on the determination of seven volatile methylsiloxanes (VMSs) and eleven UV-filters (UVFs) in beach sand from the Oporto's region (Portugal). A QuEChERS methodology (“Quick, Easy, Cheap, Effective, Rugged, and Safe”) was used to extract VMSs from the sand, which has never been employed before. To extract the UVFs, a solid-phase m...
Article
Volatile methylsiloxanes (VMSs) are massively produced chemicals that comprise a wide range of industrial and household applications. The presence of cyclic and linear VMSs in several environmental matrices and ecosystems indicates persistence associated with a potential of (bio)accumulation and food web transfer with possible toxicological effects...
Article
A Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) methodology followed by gas chromatography–triple quadrupole mass spectrometry (GC–MS/MS) analysis was developed to extract synthetic musk compounds (SMCs) (6 polycyclic, 2 macrocyclic and 5 nitro musks) and ultraviolet-filters (UVFs) (6 compounds) from sludge. This methodology fills a gap...
Article
Although sulfonamide residues are frequently reported as freshwaters contaminants, information on the ability of native bacteria to modify these synthetic antibiotics is scarce. Our purpose was to investigate the potential of bacteria from different aquatic environments to cleave or transform sulfamethoxazole (SMX) and infer on their ability to red...
Article
The European Union (EU) has recommended the monitoring of specific priority substances (PSs, Directive 2013/39) and some contaminants of emerging concern (CECs, Decision 2015/495) in surface waterbodies. The present study provides spatial distributions and temporal variations of a wide range of multi-class PSs and CECs in four stressed rivers in Po...
Article
A methodology based on solid-phase microextraction (SPME) followed by gas chromatography-tandem mass spectrometry (GC-MS/MS) has been developed for the simultaneous analysis of eleven multiclass ultraviolet (UV) filters in beach sand. To the best of our knowledge, this is the first time that this extraction technique is applied to the analysis of U...
Article
Polycyclic aromatic hydrocarbons (PAHs) are some of the most studied organic compounds in urban environments, due to their known adverse effects on human health and persistence in environmental matrices. During the last decade, new groups of organic compounds with an intensive use worldwide such as synthetic musks have been raising the interest of...
Article
Recently, Pierre Germain from CES - Silicon Europe published a comment on the paper “Volatile methylsiloxanes in personal care products – Using QuEChERS as a “green” analytical approach”, raising concerns that the artefacts employed in the analysis of cyclic volatile methylsiloxanes (cVMS) were not adequately controlled, while using this example as...
Article
Synthetic musk compounds are widely used in the formulation of several cosmetics, personal care and household products. Due to their massive and widespread use, together with some health concerns, they are considered emerging pollutants and have been detected in different environmental compartments. This study focused on the evaluation of the conce...
Article
Personal care products, an important class of emerging contaminants, have been frequently detected in different environmental matrices. Included in this category are synthetic musks compounds (SMCs) and UV-filters. Their occurrence in the coastal environment has been poorly studied. Therefore, this work aimed to verify whether five coastline plant...
Article
The use of siloxanes has been increasing due to physicochemical properties that are appropriate to be included in the formulations of a large variety of consumer products. This implies a considerable release of these chemicals into the environment, which caught the attention of the scientific community in view of some reports of potential hazardous...
Article
This study aimed to contribute to the enhancement of the knowledge of levels, trends and behaviour of eight siloxanes (four linear and four cyclic) in the environment. Adding to the prioritised scrutiny of the incidence in the atmosphere through passive samplers (sorbent-impregnated polyurethane foam disks—SIPs), the sampling of pine needles and so...
Article
Siloxane-based compounds are widely used in personal care, pharmaceutical and household products as well as in industrial applications. Among the wide variety of these chemicals, special attention has been given to volatile methylsiloxanes (VMSs). These compounds have been extensively detected in several environmental compartments, as they are not...
Article
Organosiloxanes are widely used in the formulation of a broad range of cosmetic and personal care products (PCPs), including creams and lotions, bath soaps, shampoo and hair care products to soften, smooth, and moisten. In fact, the intensive and widespread use of organosiloxanes combined with their lipophilic nature, makes them interesting targets...
Article
In this study, a solvent-saving analytical strategy was validated to quantify the levels of 8 volatile methyl siloxanes (VMSs) in pine needles, soils and air (measured by sorbent-impregnated polyurethane foam passive samplers, SIPs). Different extraction solvents and sample handling procedures were tested and the protocol that reached the highest r...
Presentation
The use of synthetic musks emerged in the 1950s [1] and have been incorporated as fragrance additives and fixative compounds in products with extremely high incidence, namely of personal care (e.g. perfumes, lotions, shampoos, deodorants, sunscreens) and household maintenance like washing powders, fabric softeners, and air fresheners [2]. Consequen...
Article
Organosiloxanes, namely volatile methylsiloxanes (VMSs) are one of the most relevant classes of ingredients incorporated in personal care products (PCPs), such as creams and lotions, bath soaps and hair care products. Their use has caused concern among the scientific community due to their potential toxic behaviour to human health and environment....
Presentation
Due to potential of bioaccumulation and biomagnification in trophic chains with possible toxicological harms, the occurrence of siloxanes in the environment is rising concerns. They are massively used in numerous industrial and consumer applications, whereby its ubiquity is considered a major concern. Several studies have shown the presence of cycl...
Article
Full-text available
This study aimed to contribute to the enhancement of the knowledge of levels, trends and behaviour of eight siloxanes (four linear and four cyclic) in the environment. Adding to the prioritised scrutiny of the incidence in the atmosphere through passive samplers (sorbent-impregnated polyurethane foam disks-SIPs), the sampling of pine needles and so...
Presentation
QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) is a recent kind of dispersive solid-phase extraction (d-SPE) that offers several advantages over traditional methods: (a) fast and easy to perform and therefore less susceptible to error; (b) uses disposable containers and devices, minimising the risk of contamination; (c) low consumption o...
Presentation
Siloxanes are organic compounds that contain a backbone of alternating Si-O units linked in a cyclic or linear way, with methyl side chains attached to each silicon atom [1]. Due to their low surface tension, high thermal stability and smooth texture, they have been used in a wide variety of personal care products (PCPs), such as shampoos, hair con...
Presentation
Synthetic musks (SMs) are widely incorporated into personal care products in order to convey a pleasant fragrance. However, due to their lipophilicity, resistance to degradation and potential negative biological effects they may pose risk to ecosystems, including biota. Therefore, an assessment of the occurrence of SMs in biota is relevant to under...
Article
UV-filters are a group of compounds which have been massively used in the past years due to the recent concerns with sunburns, premature skin ageing and the risk of developing skin cancer, related to sun exposure. At the moment, these compounds have been identified by the scientific community as emerging pollutants, due to their persistence in the...
Article
Background Synthetic musks are massively used in personal care and cosmetic products and they reach the environment mainly due to the fact that they are not completely removed from wastewater treatment plants (WWTPs). In this work, an innovative and simple chemical scoring and ranking approach was developed as a screening tool to evaluate the overa...
Article
Synthetic musks are organic compounds used as fragrance and fixative additives in several personal care products. Until now, little is known about their occurrence and distribution in these household commodities. However, this information is essential to perform a human dermal exposure assessment. Therefore, this study gives an overview on the leve...
Poster
Pesticides are compounds of great importance to sustainable agriculture, in the prevention and control of harmful organisms. Their utilisation led to the reduction of the adverse effects of diseases in crops and plants, which allowed an increase in the production [1]. Due to their highly persistent properties and toxicity, pesticides pose a serious...
Presentation
Persistent organic pollutants (POPs) are, by definition, compounds highly resistant to biological, photolytic or chemical degradation. In 2001, the Stockholm Convention has defined the first list of 12 POPs, and since then several compounds have been included or under consideration for inclusion. One of these groups of so-called ”emerging pollutant...
Presentation
Siloxanes are organic compounds used in a wide variety of personal care products, such as shampoos, hair conditioners, lotions, etc. Chemically, they consist of a structural unit of alternating Si-O bond linked into a cyclic or linear way, with organic side chains [1]. They are usually incorporated in toiletries as antifoaming and conditioning agen...
Article
UV-filters are a group of compounds designed mainly to protect skin against UVA and UVB radiation, but they are also included in plastics, furniture, etc., to protect products from light damage. Their massive use in sunscreens for skin protection has been increasing due to the awareness of the chronic and acute effects of UV radiation. Some organic...
Poster
Due to the lack of information available on the levels and presence of emerging pollutants, there are no certainties about their total impact on the environment. So, chemical scoring and ranking should be developed as a screening tool for a future risk assessment studies. Several methods have been proposed to estimate the relative impact of differe...
Presentation
Siloxanes have recently been identified as emerging contaminants and are now raising concern among the scientific community, due to a wide use in personal care products and cosmetics and also in industrial applications such as lubricants, paints, biomedical products and as antifoaming agents. Having high vapour pressure, volatilization to the atmos...
Article
Vegetation (and pine needles in particular) has been widely used as an alternative to other conventional sampling devices to assess the atmospheric presence of semi-volatile organic contaminants (SVOCs). While most analytical procedures developed focus only on one or two chemical classes, this this work intends to establish a multi-component protoc...
Article
Synthetic musks have been used for a long time in personal care and household products. In recent years, this continuous input has increased considerably, to the point that they were recognized as emerging pollutants by the scientific community, due to their persistence in the environment, and hazardous potential to ecosystems even at low concentra...
Article
This study was developed to compare from technical and economic point of view the treatment of amoxicillin (AMOX) aqueous solution by Fenton’s oxidation and adsorption with almond shell ashes. In order to degrade ppb levels of amoxicillin, the optimal conditions were obtained for both processes and each was able to totally degrade/remove the antibi...
Presentation
In quantitative analysis, sample preparation can be one of the most complex and time-consuming tasks, especially when compounds are present at trace or ultra-trace levels, due to the need to eliminate interferences and pre-concentrate the sample. Nowadays, new techniques for sample preparation not only combine the principles of green analytical che...
Article
A laboratory application with a strong component in analytical chemistry was designed for undergraduate students, in order to introduce a current problem in the environmental science field, the water contamination by antibiotics. Therefore, a simple and rapid method based on direct injection and high performance liquid chromatography–tandem mass sp...
Poster
Siloxanes have been recently identified as emerging organic contaminants (Lu et al., 2001) and are now raising concern among environmental scientists. They are classified into linear and cyclic compounds and consist of a structural unit of alternating Si-O bond with organic side chains. They have been widely used in personal care products and cosme...
Poster
The aims of the present research were: to investigate the application of QuEChERS extraction coupled to GC-MS analysis to the determination of synthetic musks in beach sands, to characterize the musk residues in this matrix and to understand their distribution in the Oporto coastal area.
Poster
The objective of this review is to draw a comprehensive picture of the presence of musks in several environmental matrices (water, air, dust, soils and plants).
Poster
A simple, fast and sensitive analytical method based on ultrasound-assisted dispersive liquid-liquid microextraction (US-DLLME) followed by gas chromatography–mass spectrometry (GC–MS) was developed and optimized for the determination of twelve synthetic musk fragrances in water samples. Several DLLME parameters, such as type and volume of extracti...
Poster
Synthetic musks are widely used in scented consumer products and are only incompletely removed by WWTPs. Due to their lipophilicity, persistence and potential biological effects they may pose a risk to ecosystems. In order to effectively assess their impact on the environment a chemical ranking and scoring methodology was developed to identify pote...
Article
The contamination of the aquatic environment by non-metabolized and metabolized antibiotic residues has brought the necessity of alternative treatment steps to current water decontamination technologies. This work assessed the feasibility of using a multistage treatment system for amoxicillin (AMX) spiked solutions combining: i) a biological treatm...
Presentation
The study of semi-volatile organic contaminants (SVOCs) still has important gaps regarding their life cycle and behaviour in the environment and even more considering the increasing amount of emerging compounds raising concern among environmental scientists. This makes all kinds of monitoring campaigns crucial, hand in hand with state-of-the-art an...
Poster
The continuous increase of the burdens of contaminants being released in the environment pose a multitude of challenges when research scientists try to study their life cycles, behaviour, patters and effects. The numerous different properties of all the matrices serving as transport media or sinks for the target pollutants raises the bar of the obs...
Poster
Vegetation has been used as passive biosamplers to evaluate atmospheric pollution. In particular, pine trees are commonly chosen due to their widespread occurrence and evergreen leafs, called needles, which allow a year-around sampling. Pine needles’ morphology presents an outer waxy cuticle, which plays an important role in the water balance of th...
Poster
Synthetic musks are used as fragrance additives and fixative compounds in personal care (e.g. perfumes, lotions, shampoos, deodorants) and household products (e.g. detergents, fabric softeners, air fresheners). Due to their high incidence and widespread use, synthetic musks are continuously introduced into the environment, mainly through urban sewe...
Poster
The widespread and intensive use of amoxicillin (AMX) has lead to environmental contamination and to an increased resistance to this beta-lactam antibiotic. Conventional methods fail to completely remove AMX and its main by-products. Our aim is to develop a two-step system combining biological and photochemical processes for the removal and mineral...
Poster
Vegetation is a useful matrix for the quantification of atmospheric pollutants such as semi-volatile organic compounds (SVOCs). In particular, pine needles stand out as effective biomonitors due to the excellent uptake properties of their waxy layer [1] and have been used to quantify the levels of several contaminants such as polycyclic aromatic hy...
Article
Synthetic musks are organic compounds used as fragrance additives and fixative compounds in a diversity of personal care products. A new method based on quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction followed by GC–MS for the analysis of 12 musks in personal care products was developed and validated. Some experimental paramet...
Poster
Pine needles have been extensively used as passive biosamplers of emergent semivolatile pollutants like polycyclic aromatic hydrocarbons (PAHs) or pesticides due to their waxy outer cuticle, which favours the entrapment of lipophilic contaminants. In line with previous research, this work intends to develop a multiresidue analytical method for POPs...
Poster
Synthetic musks are organic compounds commonly used in several cosmetics, personal care products and household products like perfumes, lotions, deodorants, soaps, shampoos, detergents, etc. According to their chemical structure, they can be divided into four major classes – nitromusks, polycyclic, macrocyclic and alicyclic musks [1]. When these per...
Poster
The 1,3,5-triazine-2,4,6-triamine, also known as melamine, is a polar and hydrophilic compound with high content in nitrogen (about 66%), mainly used in plastic industry, because of its fire retardant properties. It has been detected in milk, as result of a fraudulent addition, with the purpose of increasing the apparent protein levels. Melamine, w...
Article
Full-text available
A very simple and sensitive method was developed for the simultaneous determination of carbamate and organophosphorus pesticides in water samples, using dispersive liquid–liquid microextraction (DLLME) coupled with gas chromatography-mass spectrometry (GC-MS). Carbofuran and chlorfenvinphos were used as model molecules in this study. The optimisati...
Article
Advanced oxidation processes (AOPs) have been increasingly applied to emergent pollutants degradation. Although, homogeneous reaction by classical Fenton enables amoxicillin degradation, high iron catalyst concentrations are needed, raising environmental concerns.This work proposed an innovative and cheap solution to degrade amoxicillin by combinin...
Presentation
A simple, fast and reliable analytical method (QuEChERS/GC-MS) has been developed to analyse musks in personal care products. In this study, the extraction methodology was optimised, namely the extraction solvent and volume and sample and sorbents amount. Synthetic musks were detected in most analysed samples and galaxolide was the predominant musk...
Article
Full-text available
A new method for the simultaneous determination of 12 volatile organic compounds (trans-1,2-dichloroethene, 1,1,1-trichloroethane, benzene, 1,2-dichloroethane, trichloroethene, toluene, 1,1,2-trichloroethane, tetrachloroethene, ethylbenzene, m-, p-, o-xylene) in water samples by headspace solid phase microextraction (HS–SPME)–gas chromatography mas...
Poster
A adsorção constitui um dos tratamentos mais aplicados no tratamento de águas contaminadas. No entanto, o elevado custo do carvão activado tem incentivado a procura de materiais adsorventes alternativos, nomeadamente produtos excedentários da agricultura [1,2]. A casca de amêndoa constitui um dos maiores subprodutos agrícolas em Portugal. A produçã...