All posts by simiecoind

Abstract:

A new sensitive and selective LC-MS/MS method with positive electrospray
ionization was developed to detect seven cytostatic drugs and one metabolite from
municipal waste water. The method separates the target analytes in only 16 minutes
using a Hypersil Gold column (100 x 2.1 mm, 3.0 µm) kept at 20°C and a mobile
phase made of aq. 0.2% HCOOH and ACN in the ratio 92/8 (v/v). A low mobile phase
flow of 0.2 mL/min was used to increase MS ionization yield and hence method
sensitivity. A complex two steps (10%/minute) and two plateau gradient elution
program was applied for 12 minutes to achieve analyte separation from matrix and
each other with highly efficient peaks. Collision energy, fragmentor and capillary
voltages were optimized to increase MS sensitivity. Optimization of LC-MS
parameters generated low instrumental LOQs situated in the range 0.1 ÷ 1.0 ng/mL.
MS detector response was linear between 1 and 100 ng/mL with R2 coefficients >
0.997 for all eight target analytes. SPE using Oasis HLB cartridges was employed to
concentrate target analytes from water samples with MeOH as elution solvent. Intraday and inter-day precision (RSD %) was situated between 5.4 ÷ 7.2% and 7.3 ÷ 10.8%, respectively. Cytostatics recovery after SPE was good due to internal standard
correction with values between 70 ÷ 134%. Overall method LOQs were situated
between 0.6 and 5.6 ng/L. The method was tested on four waste water samples from
a WWTP plant in Bucharest, but none of the targeted cytostatic drugs were found
above detection limit.

Abstract:

In the last decades near the hydropower lakes, have developed numerous private
companies and settlements that constantly uses water from these lakes. In many cases,
the spills are not controlled and are not decontaminated properly or even at all. In the
Jiu hydrographic basin, there are 225 localities with a population of more than 2,000
peoples. Only 32 of them are equipped with sewer systems and only 2 of them in
accordance with Directive 91/271/EEC. As consequence of the pollution with organic
and inorganic substances (nutrients) has appeared the eutrophication of the lakes.
From the total 12-hydropower lakes with a surface over 50 ha, eight of them are
clogged in the proportion of 60%, and 3 of them in a proportion of 80%. In the first
part of the paper are analyzed the main punctual and diffuse sources of organic and
inorganic pollution, with a decisive factor in the development of the aquatic
vegetation. During 2010-2016, a systematic campaign of measurements was done.
They were determined the protection zones that need to be tracked, the catchments
zone for the human consumption, the zones for protected fish or of those species
economically important, the natural protected areas, and the zones vulnerable to
nitrate and nitrites. The obtained results are presented for the most affected
hydropower lakes from the selected area. Finally, are mentioned some possibilities
and measures necessary to be followed as to reduce the inorganic and organic
pollution, some conclusions, acknowledgement and references.

Abstract:

The aim of this study was to determine the chemical composition of wet depositions
in two locations from urban and rural area near Bucharest from January to May 2017.
For all the samples, pH, conductivity, anions, cations and heavy metals were
determined. For anions (Cl-, NO3- and SO42-) and cations (Ca2+, K+, Mg2+, Na2+)
determination an ion chromatographic method was used. Heavy metals (Co, Cr, Cu,
Mn, Ni, Pb and Zn) were determined using AAS with flame and graphite chamber.
Results showed the presence of the interested compounds in wet depositions samples
with SO42- and Ca2+ as the dominant anion and cation. Heavy metals concentration
followed the trend: Zn > Mn > Cu > Pb > Ni > Cr > Co. Analysing the results obtained
the potential sources of ambient air pollution were also suggested.

Abstract:

Volatile oils (aromatic essences) have been well known since ancient times, both as
food flavors and as a treatment solution for sanitary and cosmetic purposes.
In order to highlight the content in the volatile oils and their composition, a number
of fresh aromatic plants have been studied, as: lavender (Lavandula angustifolia),
rosemary (Rosmarinus officinalis), sage (Salvia officinalis), thyme (Thymus vulgaris)
and oregano (Origanum vulgare), all originated from the organic crops of the Hofigal
Company.
Essential oils were obtained by using the water vapor extraction technique, while for
the identification of volatile oil components was used gas chromatography coupled
with mass spectrometry (GC-MS).
The experimental results present the volatile oil content of the studied aromatic plants
and also the important and specific chemical components of each volatile oil.
Likewise, the soils used for plants growth have been analyzed for organochlorine
content by using gas chromatography with electron capture detector (ECD). The
concentration of these organic compounds is below the maximum allowable limit
established by specific law (Order no. 756/1997) for soils of Romania.
These volatile oils from organic sources will be used as raw materials for obtaining
food supplements and cosmetics products.

Abstract:

Three pharmaceutical compounds (Trimethoprim, Carbamazepine and Benzethonium
chloride) were investigated to unveil possible toxic effects on two bacterial strains
(Citrobacter freundii and Comamonas testosteroni). The pharmaceutical compounds
stress triggered a bacterial defence mechanism which was evaluated at transcriptional
and translational levels. In this study, potential bacterial biomarkers induced by the
pharmaceutical stress were unraveled.

Abstract:

The aim of this study was to estimate the sensitivity of microorganisms, isolated from
soil long-term polluted with obsolete pesticides, to magnetite (Fe3O4) nanoparticles
and fluorinated dinitroaniline herbicide trifluralin, and to evaluate the inhibition
activity of these substances. The response of fungi and streptomycete strains to the
presence of magnetite nanoparticles in culture media is individual to each
microorganism. For the most of studied microorganisms, the addition of trifluralin to
culture media had a growth inhibition effect. An exception was the strain
Streptomyces sp. 0412, which growth was stimulated in the presence of xenobiotic.
The negative effect of pesticide was reduced, when before the addition to the culture
medium the trifluralin was mixed and incubated with magnetite nanoparticles for 1
hour.

Abstract:
Water quality is assessed through the biological, physical and chemical parameters. The limits of
these parameters that are harmful to human health have been established at national or
international level (WHO, EPA, MECC) by various laws, regulations, normative. An efficient and
simplified to express the quality of water for consumption is given by the water quality index. It
reflects the quality of water in a single value by comparing data obtained from the investigation of
a number of physico-chemical and bacteriological parameters with existing limits. This number is
placed on a relative scale to justify the quality of water in categories ranging from very poor to
excellent. In this study are discussed various water quality indices used to assess the quality of
drinking water (surface water). National and international agencies involved in assessing water
quality and pollution control defines different quality criteria used for drinking water which is why
there are many water quality specific indices for each region or area. In this context, it will present
a comparative study of the most important quality indices used to assess water quality worldwide.

Abstract:
The paper presents the influence of solid waste laboratory samples homogeneity on the
determinations quality of calorific value and carbon content.
Laboratory tests were conducted for a sample of mixed solid wastes (biomass, textile, plastic).
The waste laboratory sample was prepared for physico-chemical characterisation by using basic
methods, mass and particle size-reduction of components. Particle size-reduction of components
was carried out using two laboratory mills: Retsch Rotor Beater Mill SR 300, and Retsch Vibratory
Disc Mill RS 200. Laboratory sample was prepared in two versions. In the first version (V1)
particles size reduction took place by passing a 2 mm sieve through the rotor beater mill Retsch
SR 300. The plastic component of the waste was not fully integrated into the sample. In the
second version (V2) the waste sample obtained in the first version was first pulverized in the
Retsch Vibratory Mill RS 200, followed by a comminution of the particles to diameters passing a
0,5 mm sieve through the Rotor Beater Mill Retsch SR 300. In the second version the sample
was visibly homogeneous.
Laboratory sample homogeneity influence was highlighted by determining calorific value and
carbon content of the waste sample prepared in the two versions.
Following laboratory tests the results for carbon content and calorific value were within the
repeatability limits imposed by the standardized methods for the second laboratory sample
version.

Abstract:
Economic development brings environmental concerns in general and in particular regarding the
protection against the aggression of external factors on humans, among which noise and
vibration. Noise is usually defined as a sound or the amount of unwanted sounds, a by-product
of daily activity. Environment vibrations that human body is exposed to may have different causes:
construction machinery, heavy equipment and electric hand tools. Whole human body vibrations
usually occur during transport, but can be found in other places in the course of industrial
processes. Regardless of industrial activity that cause them, vibrations acts on the human body
and this can cause discomfort to the operator. Wear of the components of industrial devices
influences both noise and mechanical vibration levels. The paper presents correlations occurring
between noise and mechanical vibrations emitted by the engine of a car depending on the number
of engine revs. For a broader characterization of emission, acoustic power and directivity factor
are calculated.

Abstract:
Atmospheric deposition means the total mass of pollutants which is transferred from the atmosphere to
surfaces (e.g. soil, vegetation, water, buildings, etc.) in a given area within a given time. Is considered to
be a major process that removes pollutants from the atmosphere and an important source of nutrients and
contaminants for ecosystems. Trace elements, especially toxic metals deposited on plants and into soil or
water, can cause substantial damage to the environment and human health due to their transfer and
accumulation in food chains.
This study aimed to determine the amount and the composition of dry deposition in a residential area in
Bucharest, organized in summer of 2016, according toDirective 2004/107/EC transposed into Romanian
legislation by Law No. 104/2011 regarding the ambient air quality.
The dry deposition samples were collected in accordance with SR EN 15841 -2010 Standard.
The major elements ( Ca2+, K+, Mg2+) and trace metals (Zn, Fe, Al, Ni, Mn, Cr, Cu, Pb and Cd) were
determined by atomic absorption spectrometry equipped with a in graphite furnace and inductively coupled
plasma optical emission spectrometry (ICP-OES), after acid digestion.
Al and Fe were recorded as the dominant metallic elementsin dry deposition followed by Zn, Ni, Cu, Pb,
and Cr. This study suggests that earth crust and anthropogenic activities such as motor vehicles were the
main sources of dust fall in the study area.

Abstract:
In the livestock sector, the livestock activity involves also an air pollution with greenhouse gases,
the main pollutants being methane, carbon dioxide and nitrogen protoxide. Depending on the
farming system, the animal breed, the food supplied to the animals, and the manure management,
various concentrations of gases with greenhouse effect may appear in the gaseous emissions.
Emissions of gaseous pollutants from buildings where the animals are kept can pollute the
atmosphere and can also affect the health of the farm workers. The natural ventilation of the
stables has a major influence on the difficulty of determining the pollutant concentrations in the
gaseous emissions, due to the inhomogeneity of the gas flow and the large variations in the
pollutant concentrations at different points that are caused by the speed of the air movement
through the venting holes and pollutant dispersion inside the building. This study presents the
results obtained in a series of measurements of the levels of greenhouse gases at a dairy farm
stable with natural ventilation. The equipment used for measurement was a portable gas
chromatograph, Varian CP 4900. During the measurements, all the animals have been in the
stable (they have not been taken to the pasture during that time).

Abstract:
The paper describes the development and optimization of an analytical technique based on
stripping voltammetry for iron determination in drinking water. The method is based on AdSV
technique and HMDE electrode. Along with the complexing agent, the catechol, a pH buffering
phosphate solution (pH 7) is added. The reference electrode is Ag/AgCl/KCl. The principle of the
method is the following: iron complexation by the catechol, adsorption of the complex on the drop
of the electrode followed by the stripping stage and practical resolubilization of the complex. Two
concentration ranges were tested: from 10 to 50µg/L and between 25 and 150µg/L. After
calibration curves were plotted, real drinking water samples enriched with iron standard solution
were analysed.
Laboratory test results indicate a very good recovery rate for the analytical trials performed
(100.44%, 104.07%, 103.49%). However, the average value of the recovery rate following all
aditions and replicates – the precision grade is 102.66%. The correlation factor between the two
curves was 0.9936 for the interval of 10- 50µg/l and 0.9989 for the interval of 25-150µg/L. The
optimised method can be easily applied in case of drinking water resources both surface and
underground water.

Abstract:
The effectiveness of some chemical matrix modifiers for the determination of lead, chromium,
selenium and arsenic in sediments and soils by Zeeman electrothermal atomic absorption
spectrometry have been evaluated. The addition of certain chemical modifiers decreases the
volatility of the analyte element, preventing its loss during pyrolysis step while increasing the
volatility of matrix components promoting a better separation also allows a higher pretreatment
temperature for better separation between analyte and matrix. Pyrolysis and atomization
temperatures, characteristic masses and detection limits of analytes in dissolved samples with
and without modifiers have been compared. The method was validated by analysing certified
reference lake sediment and soil materials.

Abstract:
In order to assess the impact of car emissions on the soil, studies are required to monitor the
concentation heavy metals from roadside soils. In this paper, we report an extensive survey
of the roadside soils contamination with heavy metal along the Sun Highway (A2) which
connects Bucharest to Constanta. The contents of heavy metals (Cd, Cu, Ni, Pb, Zn, As)
were assessed by inductively coupled plasma mass spectrometry (ICP-MS). The car
pollution was also studied to link it with the concentrations and distributions of heavy metals
in the roadside soils.