Issue 2

Polybrominated diphenyl ethers (PBDEs) are a class of widely used flame retardants that are
incorporated into a wide range of consumer products such as household appliances, plastics,
textiles and computers, to prevent fire. They were first introduced in the environment in the 1970s
and their concentrations have been increasing ever since. Their persistence in the environment,
widespread distribution and bioaccumulation in humans and wildlife has rendered them chemicals of
concern.
The main route of entry of these chemicals into the human body is via the food web, but
occupational exposure may also occur in the workplace during handling, repair and dismantling of
flame retarded goods. Inhalation of indoor air and dermal uptake may also be another important
route of entry of PBDEs into humans.
PBDEs structural similarities to better known and studied chemicals like PCBs, are causes for
concern. Individual PBDE congeners have been associated with neurotoxic effects following
neonatal exposure in animals and effects on thyroid hormone function. PBDEs have also been
associated with non-Hodgkin’s lymphoma in humans, teratogenicity and fetal toxicity. There are still
many toxicity gaps, including their carcinogenic potential and human health effects.
This paper reviews the sources and exposure of humans to PBDEs, highlighting recent scientific
data.

Coastal hydrodynamics are directly related to important environmental and ecological issues. This
paper focuses on the study of harmful phytoplankton cells’ dispersion, after an episode of an algal
bloom, based on mathematical modeling. The case of Thermaikos Gulf was used for the simulation.
The necessary hydrodynamic information was obtained by the application of a 2D hydrodynamic
model directly coupled with a transport model for the simulation of the harmful cells’ dispersion. The
model describes hydrodynamic and biological processes such as advection, dispersion and cell
growth and losses. The mechanical processes are described with the mass and momentum
conservation equations while the movement of the particles is described with the Random Walk
simulation. The biological processes of cell growth rate were described as a function of temperature
light and nutrients, and embodied to the simulation as input data for the model runs while the
biological losses are simulated by the removal of particles randomly selected from the field. The
reliability of the model was tested using data of a real algal bloom episode. Finally the study is
completed with the detection of the distribution of the harmful phytoplankton cells in Thermaikos for
different wind conditions and different sources of algal bloom.

Municipal solid waste (MSW) collection and disposal is a major problem of urban environment in
the world today. MSW management solutions have to be technologically feasible, legally and
socially acceptable and environmentally and financially sustainable. European policy is pushing to
a rational management of natural resources; a promising technological perspective today is waste
valorization, a process that becomes possible through sorting at the source, combined with material
recycling and waste-to-energy methods. On the other hand, technologies like mechanical sorting,
or disposal of MSW in landfills do not really improve MSW management efficiency. Landfills should
become the ultimate disposal site of a few inert residuals from MSW valorization. Despite all this,
conventional landfills for disposal of mixed MSW are still being constructed, with landfill site
selection being a major social problem due to the lack of public acceptance; objectivity in landfill
site selection is therefore extremely important. In Greece, we find several examples of inefficient
MSW management and curious landfill site selection. In this paper, we criticize environmental
policy issues for MSW management in Greece and identify weak points in the criteria used for the
selection of landfill sites. We conclude that there is a real need for rational MSW management
based on high quality scientific input.

Objective of the work was to investigate correlations among hazardous medical waste generation
rates and various hospital parameters in 2 departments and a clinic of a 40-bed Hellenic general
hospital (Hospital of Ikaria). Medical waste was recorded at the bio-pathology lab, the pathology
clinic and the emergency department 4 times daily during a 42 sampling day period (from December
2008 to May 2009). The hospital parameters recorded on a daily basis were the number of
examinees, the number of patients that occupied beds and the number of tests performed daily at
the clinical bio-pathology laboratory. The dependent variable was the medical waste generation rate
(kg day-1) in all cases. Statistically significant linear correlations were established in all departments;
the strongest correlation (R2≈0.75) was calculated at the clinical bio-pathology laboratory and the
weakest (R2=0.30) at the emergency department. An analysis of variance (Tukey’s t-test) and a nonparametric
statistical test revealed that medical waste generation rates from the clinical biopathology
laboratory were statistically lower in the weekends compared to weekdays. In addition,
medical waste amounts generated by the pathology clinic were statistically lower during December
and January compared to February and April.