Summary:
Urban greenery plays an important role in the quality of the lives of city
dwellers. Depending on the rate of population rise, the generation and use of
heavy metals is increased and as a result, the quality of urban environment –
including the soil, the water and the atmosphere – is downgraded, putting human
health at risk. With the help of urban environmental geochemistry, a lot of
important procedures are investigated, regarding the deposition, the spatial
distribution, the dispersion, the movement and the geochemical characteristics
of some potential dangerous trace elements in the soil. The knowledge achieved
by the aforementioned procedures, consists an important factor as far as the
estimation of environmental pollution by trace elements is concerned and the
evaluation of the possible hazards towards human health and the environment as
well.
In view of the above, within the context of the present work, a series of
geochemical environmental parameters was studied (heavy metals) in the
Environmental Awareness Park «Antonis Tritsis», a recreational area within the
urban fabric of the city of Athens. The sampling focused on two play grounds of
the park which are highly frequented by citizens on a daily basis. The
geochemical medium under examination is the upper surface soil, which is
rendered especially interesting due to its exposure to potential pollution,
mostly in the cases of children because of their incidental contact and
intrusion into their body during their play and the frequent move of hands into
their mouth.
In particular, to check the false-total concentrations of heavy metals (Pb,
Zn, Cu, Mn, Cr, Ni, Co, Cd) the soil samples were solubilised in hot acids. The
respective averages that were determined are 27, 45, 17, 272, 47, 49, 11 mg/kg.
To estimate the bio accessibility of the concentrations of heavy metals to the
upper surface soil, dilute hydrochloric acid was used in ambient temperature
and the averages that were calculated with this method are 26, 30, 10, 345, 6,
14, 8 mg/kg respectively. All the above values are extremely low compared to
international limits. In addition, to estimate the in situ heterogeneity of the
soil regarding the heavy metal concentrations, the value of relevant standard
deviation (RSDsampl%) was calculated in different spatial scales. It is
concluded that the heterogeneity is increased with the distance.
Keywords:
Urban geochemistry, Environmental pollution, Heavy metals, Soil, In situ heterogeneity
