Chemistry International
Vol. 22, No. 1
January 2000
Environmental Problems
of Greece from a Chemical Point of View
General Environmental Characteristics
of Greece
Main Problems in the Greek Environment
Environmental Policy, Monitoring, and Protective
Measures
Main Problems in the Greek Environment
Environments and ecosystems in Greece are small and fragile
and face many problems of various types. Their study, protection, and
management according to the principles of sustainability are difficult
tasks. Unfortunately, the priorities of a well-documented and low-cost
environmental policy have yet to be defined. Social pressures for better
environmental quality are still low, although many economic activities
are directly dependent on having a cleaner environment.
Although chemists play an important role in the environmental
affairs of Greece, there are many problems involved in arranging the
cooperation of scientists working in this field. Chemists, biologists,
geologists, engineers, etc., each have different scientific approaches
and different professional perspectives. There are inevitably conflicts
about work responsibilities and distribution of funds that make planning
and implementation of environmental policy difficult.
Environmental education of Greek chemists is considered
adequate. All undergraduate chemistry department curricula include courses
related to the environment, and there are also postgraduate courses.
However, the Greek Chemical Society has yet to prove that it can work
effectively in the monitoring, protection, and management of the environment.
Principal environmental problems in fields related to
chemistry and chemists are discussed briefly below.
Agriculture
Agriculture is a significant activity in Greece, and increasing
quantities of fertilizers and pesticides are consumed as the practices
of intensive agriculture are followed by farmers. Greek population employed
in agriculture in 1985 was 2 600 000, which, at 26% of the total population,
represents the highest percentage in the European Union.
Consumption of pesticides in Greece during 1989 was 7
811 t, but this quantity may have significantly increased since then.
Consumption by main category of pesticide in 1989 was as follows:
- Fungicides 1 925 t
- Herbicides 3 031 t
- Insecticides 2 844 t
- Other 11 t
Some observations of elevated concentrations of pesticides
in plants and animals have been recorded during the last few years,
and there are specialized chemical laboratories dealing with the control
of the pesticides in agricultural products, but much work remains to
be done to establish an effective monitoring system in this field.
Fertilizer consumption for 1994 was 535 000 t (171.3 t/ha/y),
broken down as follows:
- Nitrogen 334 000 t N
- Phosphate 144 000 t P2O5
- Potash 57 000 t K2O
Significant nitrogen and phosphorus loads are also generated
by the livestock population. These loads are estimated to be 145 000
t N and 27 000 t P annually. The quantities that are transferred into
the sea are estimated to be 5 000 - 15 000 t P/y and 30 000 - 130 000
t N/y.
Intensive agriculture, farming, and municipal wastes are
the main causes for the observation of red tides along Greek coasts
and for eutrophication of Greek lakes.
The main rivers of the Balkan peninsula discharge their
load into the northern section of the Aegean Sea. Their mean discharge
is about 1 000 m3/sec, which carries into the sea about 170 000 t N/y,
23 000 t P/y, and 45 - 60 Mt of suspended sediments/y. Black Sea water,
which enters the Aegean Sea through the Dardanelles, also contributes
to the enrichment of the Aegean Sea's nutrients.
River outflow has been significantly reduced during the
last 20 years because of the construction of hydroelectric dams and
the establishment of irrigation systems. Irrigated land has almost doubled
in the period 1970 - 1990; it is now about 30% of the total. The reduction
of the sediment load of the rivers leads to increased beach erosion,
to loss of deltaic environments and wetlands, and to changes in offshore
profile and shelf transport processes. The inflow of saline water into
river beds during the summer and the formation of salt wedges also disturb
the estuarine ecosystems.
Soil erosion data for 1987 indicate that this common Mediterranean
problem is severe and excessive; over 4 700 000 ha (35.6% of the total
Greek land area) and over 800 000 ha of arable land (30% of the total)
suffer from soil erosion.
Wastes
Different kinds of solid and liquid wastes pose significant
environmental problems in Greece, because there is not a sufficient
system for their management. Landfill is the principal treatment for
solid wastes, but a large percentage of these wastes are disposed in
areas without proper specifications. Many forest fires have been caused
because of this practice.
Significant quantities of liquid wastes are also disposed
of at sea or in lakes without any pretreatment. These quantities have
been reduced during the last few years through the establishment of
wastewater treatment plants in many coastal cities.
Waste generation by the industrial sector for 1990 was
as follows:
- Agriculture 90 000 t
- Mining 3 900 000 t
- Manufacturing industry 4 300 000 t
- Energy production 7 680 000 t
Municipal waste generated during 1992 amounted to 3 200
000 t (310 kg per capita) of the following composition:
- Paper and paperboard 20%
- Food and garden waste 48%
- Plastics 9%
- Glass 5%
- Metals 5%
- Textiles and other 13%
Treatment methods employed for this waste were as follows:
- Landfill 2 970 000 t
- Recycling (paper and glass) 226 000 t
Production of hazardous waste for 1992 was as follows:
- Waste oil 60 000 t
- Waste containing PCBs 1 600 t
- Clinical and pharmaceutical wastes 15 000 t
- Organic solvents 21 000 t
- Paints and pigments 6 000 t
- Resins and latex 150 t
Municipal wastewater for 1996 (5.12 x 108 m3/y) was disposed of as
follows:
- Untreated 43.5%
- After primary treatment 42.2%
- After secondary treatment 14.3%
- Into the sea or rivers through municipal sewer systems 3.74 x
108 m3/y
- Onto land 0.5 x 106 m3/y
- Into subsoil 1.36 x 108 m3/y
- In irrigation ponds 1.5 x 106 m3/y
Air Pollution
Air pollution began to be a problem in Greece after World
War II, owing to a burgeoning rate of industrialization, intense urbanization,
and economic growth. Problems are greatest in the major cities (Athens,
Thessaloniki, Patra, Iraklio, etc.).
Athens has the worst atmospheric pollution problem, mainly
because 40% of the population of the country is concentrated there,
leading to the existence of a large number of sources in a small area,
and because meteorological conditions in the area favor photochemical
reactions (air pollution of the Los Angeles type). Some years ago the
main sources of air pollution in Athens were industry and central heating,
but over the last few years automobile traffic has accounted for most
of the air pollution. The absence of an adequate road network and of
adequate public transportation creates intense traffic problems; the
speed of vehicles is very low in the city center, where the vehicle
composition is 80 - 85% private cars and taxis, 6 - 10% buses, and
6 - 14% motorcycles.
Other regions where air pollution has become an important
problem are the industrial zone of Elefsis (near Athens) and the zones
of Ptolemais (in Macedonia) and Megalopoli (in Peloponesos), where the
main power plants of the country that use lignite as a fuel are located.
In Greece, total energy production is 24 000 000 t oil
equivalent, derived from the following sources:
Lignite 35%
Petroleum 60%
Other 5%
Total renewable energy is 1 700 000 t oil equivalent,
and hydroelectric energy is 220 000 t oil equivalent.
Another point that must be taken into account in Greece
is the possible influence of the greenhouse effect and the world climate
change on the coastal zone. It is possible that the islands and coasts
could be dangerously threatened by the elevation of the sea level. Emissions
of greenhouse gases in Greece are rather small compared to those in
North Europe, but they are still a worldwide problem.
Table 1
shows pollutant emissions in Greece by source.
Air pollution is also correlated to the destruction of
forests, mainly by fires. Forest fires annually destroy areas that range
from 25 000 - 120 000 ha, while reforestation hardly covers areas more
than 5 000 ha per year. The consequences can now be seen, and many people
are becoming aware of the extent of the problem, especially since fires
in recent years (1998 included) have threatened large urban areas. Unfortunately,
most fires are caused by arson; only a few can be traced to natural
causes. Although there is a strict policy of vigilance to prevent arson,
the ecological damage stemming from forest fires continues to be very
high.
Marine Pollution
The significance of the marine environment is obvious
in a country like Greece. Most of the environmental problems of the
Greek seas are concentrated close to the large cities. Many facilities
scheduled for pollution control have either been delayed or ineffectively
designed. As a result, in many areas the levels of heavy metals, organic
pollutants, and nutrient concentrations are quite high. Many semi-enclosed
gulfs suffer seasonally from eutrophication and anoxic conditions, and
oil spills and litter have frequently despoiled Greek beaches in recent
years.
During a typical year (1995), there are records of about
300 pollution events (most of them small) along the Greek coast, attributed
to the following causes:
- 71 events could be traced to ships,
- 70 were from land-based sources,
- 9 were from other sources, and
- 145 were of unknown origin.
Furthermore,
- 209 events concerned hydrocarbons,
- 61 involved urban effluents,
- 6 concerned solid wastes,
- 5 were associated with other chemicals, and
- 2 involved color substances.
Sixty-nine of these events required use of antipollution
equipment (ships, chemicals, skimmers, gathering systems, etc.) by the
Greek coast guard to prevent damage to the marine environment.
During the period 1991 - 1993, Greek courts have ordered
those responsible for more than 1 000 pollution events (approximately
650 from ships and 350 from land-based sources) to pay more than a billion
drachmas (about USD 400 million) in damages.
Petroleum escaping into the sea from land-based sources
and also from marine activities has been reduced in the Mediterranean
after the implementation of the MAR-POL convention, but some accidents
have caused environmental damage. Since 1980, ten significant accidents
(more than 500 t of petroleum discharged into the sea) have occurred
in different regions of the Aegean. Pollution from petroleum has led
to observation of tar balls along almost every coastline. The wide range
of polynuclear aromatic hydrocarbon (PAH) concentrations measured in
the Aegean indicates that the most significant pollution remains restricted
to near the shore and to enclosed areas.
The inadequate cooperation between Greece and Turkey is
an impediment to efforts for protection of the marine environment in
the area. The debate between the two countries has a long historical
background, but it is also related to management of the wealth of the
continental shelf of the Aegean Sea.
Regarding the quality of bathing water, it is well known
that the Aegean Sea is one of the main tourist areas of the Mediterranean;
thus, seawater quality has an important significance for vacationers.
There is a systematic monitoring of the Greek coastline for total and
fecal coliforms from April to October. For 1995, areas that were not
in compliance with quality requirements of the European Union comprised
0.7% of 1 500 points along the Greek coast.
The most important and best-studied coastal areas are
those of the Saronikos Gulf and the Gulf of Elefsis (near Athens) and
the Thermaikos Gulf (near Thessaloniki); both areas are semi-enclosed
systems that are influenced by pollution activities and have relatively
weak currents. Tidal currents are weak in the Mediterranean and along
the Greek coast amount to 30 - 50 cm at most.
The Saronikos Gulf is considered to be among the most
polluted Greek gulfs, and the Gulf of Elefsis is the most eutrophic
area in the whole Saronikos region because nutrients are also released
from sediments in anoxic periods. About 40% of Greek industries are
located on the coast of Attiki, along the northern part of the Saronikos
Gulf, and large amounts of industrial effluents (about 100 000 m3/day)
are discharged into the sea in this area. Some of the principal industries
(oil refineries, shipyards, chemical plants, food processing plants,
metals shops, cement industries, etc.) are located within Elefsis Bay.
It is estimated that about
20 000 t of petroleum are discharged annually into the Saronikos Gulf.
During the period 1986 - 1991, about 130 pollution events
from ships and about 25 from refineries and industries have been recorded
in the Saronikos Gulf.
For many years, untreated sewage from Athens (about 600
000 m3/day) was discharged into the shallow Keratsini Bay through the
Central Sewage Outfall. Since September 1994, primary treatment of wastes
from Athens has been carried out at the Sewage Treatment Plant at Psytallia
Island. The total amount of organic load removed is around 40%. Disposal
of effluents through two pipes placed 30 m below the surface at the
bottom of the Saronikos Gulf has led to significant differentiation
in the distributions of dissolved oxygen and nutrients in the Saronikos
Gulf.
Pollution in the Saronikos Gulf influences the abundance,
composition, and structure of plankton. Furthermore, pollution tends
to reduce the number of species. The benthic fauna of the Gulf are also
disturbed mainly in the Gulf of Elefsis, in Keratsini, and near Psitalia
where there are extended azoic zones. There is also a disturbance in
the population of Posidonia oceanica, as it is well known that
Posidonia is heavily affected by pollution of the Gulf and also
by various construction activities in the coastal zone.
The Thermaikos Gulf is a semi-enclosed area into which
four major rivers (Aliakmon, Loudias, Axios, and Gallikos) flow, enriching
it with organic carbon, nutrients, and particulate matter. Nutrient
concentrations at the mouths of the rivers are high, and the Thermaikos
Gulf has nutrient values 2 - 6 times higher than an oligotrophic area.
As a consequence, red tides and phytoplankton blooms have been observed
at times in the Thermaikos Gulf, and anoxic conditions develop during
the summer period near the harbor of Thessaloniki. Thermaikos Gulf is
actually heavily polluted by sewage from Thessaloniki and by industrial
effluents from about 250 factories. The sewage waters are estimated
at 150 000 m3/d, of which only 30% are treated. A new treatment plant
is under construction to handle the entire quantity of sewage.
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