**2. Current obstacles in biota monitoring**

Starting from the early of XX century, scientific communities at worldwide scale started to put questions regarding the possibility of humans' exposure to unwanted chemical contaminants as well on the facts that could resulted after exposure events to such chemical contaminants. Thus in 1973, was initiated through World Health Organization the Environmental Health Criteria Programme which presented at that time these emerging objectives:


Nowadays, in medicine and ecotoxicology fields, it is widely accepted that contaminants effects testing must involve animals because in most cases researches performed on animals

Non-Invasive Matrices Use in Pollution Evaluation

increasingly difficult to be fulfilled in researcher studies.

environmental contaminants.

were chosen on the following principles:

the studied organisms

environment.

study

**2.2 Current trends in living things exposure monitoring** 

**3. Choice of sample matrix type collected non-invasively** 

at Nanoscale Levels: A Way Forward in Ecotoxicological Studies 171

Moreover, in terms of ecotoxicological studies performed on animal subjects in most situations the performed studies were completed by their sacrifice. Considering these, in the recent years at world wide it has brought up repeatedly in discussions the ethical aspects throughout these studies are conducted (Watson, 2009). But considering the importance of such kind of study (mainly as regards environmental contaminants biomonitoring or their toxicological evaluation on living things) by which obtained information make possible to take measures (pollutants presence regulation through law, contaminated environment remediation) or get treatment measures (in case of diseases) made them until now

Today a large number of countries introduce regulation regarding the way through that are performed these studies, imposing clear conditions as limiting the number of animal subjects subjected for study as well regarding the mode through that they are treated during the experiment. Unfortunately, considering these requirements in most cases the necessity of a large number of data (which obviously involve uses of a large number of subjects) is

Taking into account the requirements imposed by legislation but also by the need of a large number of subjects submitted for study so that to could draw realistic and convincing conclusions induced the need to seek new ways for ecotoxicological evaluation of

In an attempt to meet these ideas has emerged and formed a new path in ecotoxicological assessment of chemical pollutants, namely qualitative and quantitative evaluation of chemical contaminants from biological matrices from living beings using noninvasive sampling ways. This new direction in ecotoxicological biomonitoring of environmental contaminants not only allows the monitoring of animal subjects exposed but make also possible to assess the impact of those chemical contaminants on humans that leave in contaminated areas. Also this way of sampling of biological matrix from living beings allows an extension of studied subjects in terms of both as species, age, gender and living

As in any case of chemical pollutants monitoring a sample must to render an accurate picture about chemical compounds composition present in the environmental media from which the sample was taken at the sampling moment. In order of eliminating the problems of invasive sampling method of biological matrix from living beings, now sample matrixes

primarily to not cause any kind of discomfort, pain or sacrifice to subjects submitted for

 to be stable in time without altering the sample and the chemical structure, physicochemical properties and quantities of the monitored chemical contaminants to be a representative "mirror of the footprint" leaved by the chemical contaminants on

acceptable and necessary even in conditions of sacrifice of studied animal subjects.

helped scientists to discover and developed lifesaving treatments and medications, and to observe which chemical compounds might be dangerous to humans if they get contact with it through ingestion, inhalation and/or dermal contact. But even if we consider all benefits that were obtained in humans health science through animal testing, not everyone consider animal testing as the best method for toxicology. There are two major reasons for that they are not totally accepted, once due to the fact that toxicological study performed on animal subjects induce terrible pain on them, most of the time resulting in the animal subjects death, and secondly due to the fact that not always the approximation between the selected testing animal species physiology and their anatomical profile is similar enough with that of humans (Watson, 2009).

Leaving aside whether if the chosen animal subjects in the study correspond entirely in term of physiological and anatomical structure to humans, when we want to have certainty that a chemical compounds is able to leave some imprint on a living things, study on any kind of animal subject becomes priority. Based on the presence of a chemical compounds on a animal subject, scientist can made analogy about the possibility of this chemical compound presence in human body.

Taking into account all that were presented before as well the controversies that have arisen in the recent years regarding testing on animal subjects, today more and more researchers are trying to develop novel testing methods that are not invasive to the subjects in question.

Development of such of kind methods is beneficial even for human biomonitoring, permitting a larger number of studies on a wider range of subjects as age, gender and geographical living position.

#### **2.1 "Old sampling methods" in monitoring of living things exposure to organic contaminants**

Human biomonitoring used for determination of chemical substances in body fluids was for the first time introduced in the early of 1930's by occupational medicine for health protection of exposed workers (Angerer et al, 2007). The first biological sample matrixes that were used was blood and urine, (blood being the first biological sample collected through invasive mode while urine was the first biological sample matrix that was sampled through non-invasive ways). The benefits of using biological samples in order to get information regarding human exposure made that this mode of humans health evaluation in terms of exposure to chemical contaminants to expand, so today it is used in areas like public health politics, environmental medicine, toxicology and other science that relate to the impact of chemical compounds on human health.

Usually, testing the qualitative as well quantitative presence of any kind of chemical compounds in living organisms, involve the use of sample matrixes as blood, tissues or bones. Although in terms of pollutants biomonitoring from living things it is considered that blood samples offer the most accurate information regarding the quantitative presence of a pollutants or its metabolites (due to the fact that it's get contact with the whole organism), this test specimen is done by venipuncture (piercing artery or vein) which cause pain and discomfort to subjects (Beebee, 2008). As regards bone or tissue sampling methods, these are more painful causing in most cases severe injuries.

helped scientists to discover and developed lifesaving treatments and medications, and to observe which chemical compounds might be dangerous to humans if they get contact with it through ingestion, inhalation and/or dermal contact. But even if we consider all benefits that were obtained in humans health science through animal testing, not everyone consider animal testing as the best method for toxicology. There are two major reasons for that they are not totally accepted, once due to the fact that toxicological study performed on animal subjects induce terrible pain on them, most of the time resulting in the animal subjects death, and secondly due to the fact that not always the approximation between the selected testing animal species physiology and their anatomical profile is similar enough with that of

Leaving aside whether if the chosen animal subjects in the study correspond entirely in term of physiological and anatomical structure to humans, when we want to have certainty that a chemical compounds is able to leave some imprint on a living things, study on any kind of animal subject becomes priority. Based on the presence of a chemical compounds on a animal subject, scientist can made analogy about the possibility of this chemical compound

Taking into account all that were presented before as well the controversies that have arisen in the recent years regarding testing on animal subjects, today more and more researchers are trying to develop novel testing methods that are not invasive to the subjects in question. Development of such of kind methods is beneficial even for human biomonitoring, permitting a larger number of studies on a wider range of subjects as age, gender and

**2.1 "Old sampling methods" in monitoring of living things exposure to organic** 

Human biomonitoring used for determination of chemical substances in body fluids was for the first time introduced in the early of 1930's by occupational medicine for health protection of exposed workers (Angerer et al, 2007). The first biological sample matrixes that were used was blood and urine, (blood being the first biological sample collected through invasive mode while urine was the first biological sample matrix that was sampled through non-invasive ways). The benefits of using biological samples in order to get information regarding human exposure made that this mode of humans health evaluation in terms of exposure to chemical contaminants to expand, so today it is used in areas like public health politics, environmental medicine, toxicology and other science that relate to the impact of

Usually, testing the qualitative as well quantitative presence of any kind of chemical compounds in living organisms, involve the use of sample matrixes as blood, tissues or bones. Although in terms of pollutants biomonitoring from living things it is considered that blood samples offer the most accurate information regarding the quantitative presence of a pollutants or its metabolites (due to the fact that it's get contact with the whole organism), this test specimen is done by venipuncture (piercing artery or vein) which cause pain and discomfort to subjects (Beebee, 2008). As regards bone or tissue sampling methods, these are

humans (Watson, 2009).

presence in human body.

geographical living position.

chemical compounds on human health.

more painful causing in most cases severe injuries.

**contaminants** 

Moreover, in terms of ecotoxicological studies performed on animal subjects in most situations the performed studies were completed by their sacrifice. Considering these, in the recent years at world wide it has brought up repeatedly in discussions the ethical aspects throughout these studies are conducted (Watson, 2009). But considering the importance of such kind of study (mainly as regards environmental contaminants biomonitoring or their toxicological evaluation on living things) by which obtained information make possible to take measures (pollutants presence regulation through law, contaminated environment remediation) or get treatment measures (in case of diseases) made them until now acceptable and necessary even in conditions of sacrifice of studied animal subjects.

Today a large number of countries introduce regulation regarding the way through that are performed these studies, imposing clear conditions as limiting the number of animal subjects subjected for study as well regarding the mode through that they are treated during the experiment. Unfortunately, considering these requirements in most cases the necessity of a large number of data (which obviously involve uses of a large number of subjects) is increasingly difficult to be fulfilled in researcher studies.
