and are not completely removed from the activated sludge treatment plants. Hence,
they are a source of concern due to the harmful effects that these substances can
cause in a variety of aquatic and terrestrial organisms due to their continuous entry
into the environment.
The main drawback arising from the application of wastewater effluents is that
vegetables could uptake PhACs from soil and water, leading to their accumulation at
trace level in fresh products for human consumption [2]. In fact, the main disadvantage of wastewater reuse in agriculture is the potential contamination of soil, crops,
and water sources and the inherent risk of harmful effects that contamination poses
to exposed organisms. However, the PhAC concentrations in crops and vegetables
should be much lower than the dosage for an effective therapy.
Every day, due to the constant development of the pharmaceutical industry, new
compounds are approved and marketed. However, there is a general lack of knowledge of the effects that these substances cause on the environment. This is explained
in part due to the reduced number of studies or the intrinsic difficulty of extracting
and isolating and quantifying organic compounds at trace levels in soil and plants.
Moreover, the analytical techniques used for this type of pollutants are relatively
expensive.
Although several analytical methods have been developed to extract PhACs from
water and soil samples, one of the greatest efforts of recent years is to try to develop
robust analytical methods for the analysis of PhACs in plant tissues. Given the small
number of these publications, it is evident how this issue represents a difficult
challenge to overcome. Furthermore, the use of an inappropriate or low sensitive
method with relatively high limits of quantification could contribute to give
unreliable results as a consequence of the low concentrations with which these
compounds are present in water or in the soil.
Due to the complexity of the sample matrix, the analysis of environmental
samples involves several difficulties. The analyses of solid or semi-solid matrices
such as soil, sludge, or sediment or of biological samples (animal, vegetable, or
plasma tissues) are more complex than liquid samples, which usually require fewer
pretreatment phases, due to their liquid form. In the case of wastewater, for example,
an initial filtration is sufficient to remove the particulates followed by a solid-phase
extraction using cartridges with different absorbent resins. The latest technological
advances also allow for the analysis of surface or wastewater by direct injection
avoiding all the problems related to the handling of the sample [3, 4].
Sample preparation has simply the purpose of transferring the analytes in a
measurable form [5]. The first step for the success of an analytical method is
sampling. In fact, the determination of pollutants in soil or plants initially requires
specific sampling techniques that take into account the heterogeneity of the soil or
plant matrix [6].
Furthermore, the sample preparation for the analysis of pharmaceutical residues is
a very critical aspect since the analytes of interest are intimately bonded to the
components of the matrix to be studied. Indeed, prior to the analysis, specialized
extraction techniques are needed that can effectively isolate the analytes without any
component of the matrix potentially interfering with the detection of the analyte. The
Development of Methods for the Determination of PhACs in Soil/Earthworm/Crop. . .
419
they are a source of concern due to the harmful effects that these substances can
cause in a variety of aquatic and terrestrial organisms due to their continuous entry
into the environment.
The main drawback arising from the application of wastewater effluents is that
vegetables could uptake PhACs from soil and water, leading to their accumulation at
trace level in fresh products for human consumption [2]. In fact, the main disadvantage of wastewater reuse in agriculture is the potential contamination of soil, crops,
and water sources and the inherent risk of harmful effects that contamination poses
to exposed organisms. However, the PhAC concentrations in crops and vegetables
should be much lower than the dosage for an effective therapy.
Every day, due to the constant development of the pharmaceutical industry, new
compounds are approved and marketed. However, there is a general lack of knowledge of the effects that these substances cause on the environment. This is explained
in part due to the reduced number of studies or the intrinsic difficulty of extracting
and isolating and quantifying organic compounds at trace levels in soil and plants.
Moreover, the analytical techniques used for this type of pollutants are relatively
expensive.
Although several analytical methods have been developed to extract PhACs from
water and soil samples, one of the greatest efforts of recent years is to try to develop
robust analytical methods for the analysis of PhACs in plant tissues. Given the small
number of these publications, it is evident how this issue represents a difficult
challenge to overcome. Furthermore, the use of an inappropriate or low sensitive
method with relatively high limits of quantification could contribute to give
unreliable results as a consequence of the low concentrations with which these
compounds are present in water or in the soil.
Due to the complexity of the sample matrix, the analysis of environmental
samples involves several difficulties. The analyses of solid or semi-solid matrices
such as soil, sludge, or sediment or of biological samples (animal, vegetable, or
plasma tissues) are more complex than liquid samples, which usually require fewer
pretreatment phases, due to their liquid form. In the case of wastewater, for example,
an initial filtration is sufficient to remove the particulates followed by a solid-phase
extraction using cartridges with different absorbent resins. The latest technological
advances also allow for the analysis of surface or wastewater by direct injection
avoiding all the problems related to the handling of the sample [3, 4].
Sample preparation has simply the purpose of transferring the analytes in a
measurable form [5]. The first step for the success of an analytical method is
sampling. In fact, the determination of pollutants in soil or plants initially requires
specific sampling techniques that take into account the heterogeneity of the soil or
plant matrix [6].
Furthermore, the sample preparation for the analysis of pharmaceutical residues is
a very critical aspect since the analytes of interest are intimately bonded to the
components of the matrix to be studied. Indeed, prior to the analysis, specialized
extraction techniques are needed that can effectively isolate the analytes without any
component of the matrix potentially interfering with the detection of the analyte. The
Development of Methods for the Determination of PhACs in Soil/Earthworm/Crop. . .
419