**Non-Invasive Matrices Use in Pollution Evaluation at Nanoscale Levels – A Way Forward in Ecotoxicological Studies**

Melinda Haydee Kovacs1, Dumitru Ristoiu2 and Cezara Voica1 *1National Institute for Research and Development of Isotopic and Molecular Technologies Cluj-Napoca, 2Environmental Science and Engineering Faculty, Babes-Bolyai University Cluj-Napoca, Romania* 

## **1. Introduction**

"For the first time in the history of the world, every human being is now subjected to contact with dangerous chemicals, from the moment of conception until death" – R. Carson, Silent Spring.

This is a quote that summarizes the reality at this moment regarding our safety in our surrounding environment, wherever we are. Unfortunately, pollutants imminence is more increased in developing countries, given that they register higher level of pollutants in all environmental compartments owing to their poor pollution control and pollutants monitoring.

In most cases, environment contamination is a result of humanity's lifestyle resulted from industrial-, agricultural activities and extended urbanization. For most of us it is more and more difficult to imagine our lifestyle from every day without using and profit of products stocked by chemical industry such as pharmaceuticals, petrochemicals, agrochemicals and many other consumer chemicals (Bhandari et al, 2009). Unfortunately together with the rise of chemical manufacture and its use has also come increasing public awareness and concern regarding presence of these chemicals in our surrounding environment. Concernments are mainly caused by the physicochemical properties of these chemical compounds and their possible negative consequence linked to human health and biota.

Owing to awareness's that was attributed by scientific communities and mass media to environmental pollution and living things exposure to such chemicals, has made a clutter regarding the terms like contamination and pollution, terms that tend to be use as synonyms (Hansen, 1993). On our days has been made an agreement between scientific experts, decision-makers and inspectors from different authorities at worldwide level, in that the term contamination should be used where a chemical is present in a given sample with no concrete evidence of harm while the term pollution could be used in cases where was

Non-Invasive Matrices Use in Pollution Evaluation

at Nanoscale Levels: A Way Forward in Ecotoxicological Studies 169

As regards living beings, concernment regarding our surrounding environment contamination is amplified by issues as movement of toxic contaminants from contaminated media in food products whatever we refers to vegetables or animals grown for consumption purposes. Therefore, humans are not exposed to chemical contaminants just through environmental

Considering the lack of knowledge regarding the additive harm effects of such pollutants on biota (even if we talk about human subjects or animal subjects), becomes more necessary to pay a special attention to identifying, both qualitatively as well quantitatively, the presence of organic chemical contaminants in living beings. Therefore, is important to develop new, accurate and fine analytical methods for analysis of chemical contaminants at very low levels (micro- and nano- orders) from complex biological and environmental matrixes.

Unfortunately even at the present moment, when we want to evaluate the presence of such chemicals in living organisms toward formation of their ecotoxicological profiles, almost all analysis methods use invasive sampling protocols which in a large number of cases, especially in studies on animals, result in causing harm or death of the studied subjects. Introducing of analytical methods which use non-invasive sampled matrixes as saliva, hair, nail, milk, etc., will blot out problems regarding: causing harm (to human or animal subjects) or loss of studied subjects as animals; available number of analysis (referring to the

Development of analytical methods for non-invasively collected biological samples will help in future to provide a better image regarding the contamination with complex chemicals of biota as well will help to get a better understand about their eco-toxicological hall-mark on

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

 to assess the biological/zoological specimens which are the most suitable for contaminants monitoring thus to get information on the relationship between exposure to environmental chemical contaminants and human health, in order that in future to

to develop guidelines for sampling, sample preparation, analytical requirements and

to promote the harmonization of toxicological and epidemiological methods in order to

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

number of human and animal subjects monitoring); and sample collection process.

any living organisms (whether we refer to human or animal subjects).

could provide guidelines for setting useful exposure limits;

have internationally comparable results (WHO, 2006).

to draw up recommendation for further research and development;

**2. Current obstacles in biota monitoring** 

to identify new or potential pollutants;

storage relative to biomonitoring;

objectives:

media or workplaces (particular cases) but also along food chains (Walker, 2009).

demonstrated that the presence of the chemical compounds caused harm for humans or to other living things (Neuzil et al, 1996).

Doubtlessness any chemical compounds can become a pollutant in any kind of environmental media (water, soil, air, etc.) causing negative effects if it is at a high enough concentration. Despite the fact that any chemical compounds can be a pollutant, certain chemicals have been identified in regulations or by international agreements as being priority chemicals for control (Harrison, 2001). These chemicals have been selected based on their: frequency found in surrounding environment at global scale; persistence in different media; toxic effects at low concentration (damage of selected organs, mutagenic and teratogenic effects) and carcinogenesis; and not in the last case based on their increased bioaccumulation capacity (Pierce et al, 1998).

Living organisms including humans are exposed to chemical contaminants, called also as environmental toxicants, via environmental media. Exposure might be occurred by breathing, ingestion by drinking liquids or eating nourishments that contain chemical contaminants, or through skin contact – see figure 1.

Fig. 1. Humans exposure pathways to organic chemical compounds contaminants.

When living organisms are exposed to environmental contaminants, a cascade of chemical, biological and biochemical events take place in them. These effects intensity depends strongly on exposure conditions – thus when we talk about exposure we must to take into account the dose of chemical contaminants (how much by the chemical substances are ingested, inhaled or imbibed through skin contact), the time period of exposure and the way through that living beings get contact with them. Also is necessary to look at the other chemical contaminants hereat the people are exposed (mixture effects) as well their age, gender, diet, lifestyle, family trails and state of health. Even in our day is difficult to give concrete answers to questions regarding organic chemical contaminants movement and distribution in the living environment – within individual living beings, communities and ecosystems – where multiple factors and events come in to play resulting usually in unwanted events and effects (Walker, 2009). In the last decades many studies underlined that contaminants conspecific to organic chemical classes result in different types of harmful effects on humans or other existences (Byres, 2006).

demonstrated that the presence of the chemical compounds caused harm for humans or to

Doubtlessness any chemical compounds can become a pollutant in any kind of environmental media (water, soil, air, etc.) causing negative effects if it is at a high enough concentration. Despite the fact that any chemical compounds can be a pollutant, certain chemicals have been identified in regulations or by international agreements as being priority chemicals for control (Harrison, 2001). These chemicals have been selected based on their: frequency found in surrounding environment at global scale; persistence in different media; toxic effects at low concentration (damage of selected organs, mutagenic and teratogenic effects) and carcinogenesis; and not in the last case based on their increased

Living organisms including humans are exposed to chemical contaminants, called also as environmental toxicants, via environmental media. Exposure might be occurred by breathing, ingestion by drinking liquids or eating nourishments that contain chemical

Fig. 1. Humans exposure pathways to organic chemical compounds contaminants.

When living organisms are exposed to environmental contaminants, a cascade of chemical, biological and biochemical events take place in them. These effects intensity depends strongly on exposure conditions – thus when we talk about exposure we must to take into account the dose of chemical contaminants (how much by the chemical substances are ingested, inhaled or imbibed through skin contact), the time period of exposure and the way through that living beings get contact with them. Also is necessary to look at the other chemical contaminants hereat the people are exposed (mixture effects) as well their age, gender, diet, lifestyle, family trails and state of health. Even in our day is difficult to give concrete answers to questions regarding organic chemical contaminants movement and distribution in the living environment – within individual living beings, communities and ecosystems – where multiple factors and events come in to play resulting usually in unwanted events and effects (Walker, 2009). In the last decades many studies underlined that contaminants conspecific to organic chemical classes result in different types of harmful

other living things (Neuzil et al, 1996).

bioaccumulation capacity (Pierce et al, 1998).

contaminants, or through skin contact – see figure 1.

effects on humans or other existences (Byres, 2006).

As regards living beings, concernment regarding our surrounding environment contamination is amplified by issues as movement of toxic contaminants from contaminated media in food products whatever we refers to vegetables or animals grown for consumption purposes. Therefore, humans are not exposed to chemical contaminants just through environmental media or workplaces (particular cases) but also along food chains (Walker, 2009).

Considering the lack of knowledge regarding the additive harm effects of such pollutants on biota (even if we talk about human subjects or animal subjects), becomes more necessary to pay a special attention to identifying, both qualitatively as well quantitatively, the presence of organic chemical contaminants in living beings. Therefore, is important to develop new, accurate and fine analytical methods for analysis of chemical contaminants at very low levels (micro- and nano- orders) from complex biological and environmental matrixes.

Unfortunately even at the present moment, when we want to evaluate the presence of such chemicals in living organisms toward formation of their ecotoxicological profiles, almost all analysis methods use invasive sampling protocols which in a large number of cases, especially in studies on animals, result in causing harm or death of the studied subjects. Introducing of analytical methods which use non-invasive sampled matrixes as saliva, hair, nail, milk, etc., will blot out problems regarding: causing harm (to human or animal subjects) or loss of studied subjects as animals; available number of analysis (referring to the number of human and animal subjects monitoring); and sample collection process.

Development of analytical methods for non-invasively collected biological samples will help in future to provide a better image regarding the contamination with complex chemicals of biota as well will help to get a better understand about their eco-toxicological hall-mark on any living organisms (whether we refer to human or animal subjects).
