2. Anthropic impact and natural disasters
2.1. Air
2.1.1. Pollution sources and ambient air quality
The quality of the ambient air in the Republic of Moldova is influenced by internal and external
pollution sources. The background concentrations of air pollutants are largely determined by
transboundary fluxes (fig. 2.1).
All over the world, industrial and energy sectors and transport are the main sources of air
pollution and Moldova makes no exception. The pollution level is significantly higher in urban
agglomerations and residential areas where the main industrial sites and power generation units
are located and where there is intense traffic. In many of such areas, air pollution is a priority
issue.
The volume of emissions into the atmosphere from stationary pollution sources (including the
largest national power generation station in Dnestrovsk, Transnistrian region, 2520 MW)
amounted to 32,600 tons, including: particulates – 15.6%, carbon monoxide – 13.5%, NOx –
29.1%, sulphur dioxide – 39.4%. From these, the emissions of the Dnestrovsk PGS accounted
for 16,992 tons or 52% of the total amount released from the stationary sources (fig. 2.2).
Without taking into account the Transnistrian region (which is out of central government
jurisdiction), the emissions from stationary sources increased from 14,500 tons in 2001 to 15,600
tons in 2002 (+ 8.1 %) (fig. 2.1, 2.2).
In 2002, a slight increase of total air emissions was recorded comparing to the year 1999 (which
was the minimum year in terms of polluting emissions), a fact attributed to some recovery of the
energy sector. However, comparing to the year 1990, the total emissions decreased in 2002 by a
factor of 6 (in 1990 – 1045 kt, in 1999 – 147 kt, in 2002 – 187 kt).
20
02
20
01
20
00
19
99
19
98
19
97
19
96
19
95
19
94
19
93
19
92
19
91
19
90
th. tons
stationary
mobile
Fig. 2.1. Air emissions from stationary and mobile pollution sources
The large power generation units are the main stationary sources of pollution at the national
level. In small towns, the communal boiler-houses can be a significant local air pollution source.
By switching those units from coal/fuel oil to natural gas, air emissions can diminish. In 2002, 56
boiler-houses have been transferred to natural gas, additionally to 531 such units existing in
2001.
The power and heat generation units account for 84% of the emissions from stationary sources.
However, the mobile sources dominate in the total air pollution structure.
250
th. tons
200
150
100
50
0
1990
1991
hydrocarbons
1992
1993
particulates
1994
1995
1996
nitrogen dioxide
1997
1998
1999
sulphur trioxide
2000
2001
2002
carbon monoxide
Fig. 2.2. Major air pollutants from stationary sources
During the last decade, the share of cars in the transportation of passengers and goods increased.
In the same time, the number of private cars had a spectacular evolution since the early 1990s.
Most of the imported cars, however, are second-hand cars, some of them in poor condition.
Together with the limited capacity of the authorities to check the quality of exhaust gases and to
control the technical condition of cars, and the poor service of transport units in many car
companies, this has leaded to the deterioration of the air quality in urban areas with a negative
impact on the health of the population.
The share of electrical public transport is, unfortunately, continuously declining. The number of
trolley-buses in the cities decreased from 605 units in 1990 to 393 in 2001.
From the greenhouse gases, carbon dioxide emissions in 2001 decreased to 6343 Gg or 23.1%
from the reference year 1990 (fig.2.4).
160000
140000
1996
120000
1997
100000
1998
80000
1999
2000
60000
2001
40000
2002
20000
yre
ne
be
nz
(a)
p
lea
d
tes
r ti
cu
la
pa
lph
ur
dio
xid
e
su
rio
xid
e
su
lph
ur
t
on
s
hy
dro
ca
rb
ca
rb
on
mo
no
xid
e
0
Fig. 2.3. Major air pollutants from mobile sources
The quality of the atmospheric air in Moldova is monitored by the Hydrometeorological Service
at 17 stationary stations located in 5 main cities/industrial centres and at the background
monitoring station Hancesti. In 2002, the following parameters were monitored in the cities:
sulphur dioxide, carbon monoxide, nitrogen dioxide, particulates, phenols, formic aldehide,
sulphates.
In 2002, the national annual average of the integrated air pollution index was 5.85, with seasonal
variations between 3.26 in December and 11.23 in March.
The air quality monitoring network in Chisinau consists of 6 stationary posts located within the
city boundaries. During 2002, 13114 ambient air samples were taken and analysed at these
monitoring stations. The average annual concentration of nitrogen dioxide exceeded the existing
air quality standard (maximum admissible concentration, MAC) by a factor of 1.29, the formic
aldehide, by 1.9. According to monthly averages, the highest pollution levels were recorded: for
particulates, in January (1.3 MAC); for carbon monoxide, in January and February (0.8 MAC);
for nitrogen dioxide, in October (2.7 MAC); for sulphur dioxide, in November (1.5 MAC).
Comparing to the year 2001, the pollution with nitrogen dioxide (annual average values)
increased while the particulates, carbon monoxide and formic aldehide, decreased.
In the city of Balti, the average air pollution index in 2002 was 8.61, with monthly variations
from 7.59, in August to 9.49, in September. The admissible average annual concentrations were
exceeded for particulates (1.9 MAC); nitrogen dioxide (1.5 MAC); sulphur dioxide (1.1 MAC)
and formic aldehide (2.6 MAC). As regards monthly average values, the highest exceedances
were recorded for particulates (2.3 MAC), in May; for sulphur dioxide (1.3 MAC), in
Year 1990, Total CO2 - 289233 Gg
5%
8%
25%
natural gas
fuel oil
23%
diesel
coal
petrol
others
27%
12%
Year 1998, Total CO2 - 8900 Gg
9%
7%
natural gas
fuel oil
9%
diesel
coal
58%
9%
petrol
others
8%
Year 2001, Total CO2 - 6543 Gg
10%
6%
natural gas
11%
fuel oil
diesel
coal
petrol
60%
10%
3%
Fig. 2.4. Dynamics of CO2 emissions from combustion of fossil fuels
others
September; for nitrogen dioxide (1.7 MAC), in September and for formic aldehide (3.1 MAC), in
April. Comparing to the year 2001, pollution with nitrogen dioxide and formic aldehide (annual
average values) increased while the level for particulates, carbon monoxide and sulphur dioxide
decreased.
In the city of Tiraspol, the average air pollution index was 4.25, showing an insignificant rise
comparing to the last year. Along the year, the index varied between 3.03 in October and 6.19 in
August. The admissible annual mean was exceeded only for formic aldehide (1.8 MAC). The
highest level of pollution, according to monthly means, was recorded for particulates (1.45
MAC), in April, for nitrogen dioxide (1.1 MAC), in December, for phenols (1.6 MAC), in July,
for formic aldehide (3.0 MAC), in September. Comparing to 2001, pollution with nitrogen
dioxide, formic aldehide, phenols and carbon monoxide (annual average values) increased while
the particulates, carbon monoxide and sulphur dioxide decreased.
In the city of Ribnita, no significant changes in air quality were recorded in 2002, comparing to
2001. The air pollution index was 2.29, with variations between 1.76, in January, and 2.85, in
May. The admissible annual mean was exceeded only for nitrogen dioxide (1.1 MAC). In terms
of monthly average values, the highest level of pollution was registered for nitrogen dioxide (1.5
MAC), in May. Other ingredients did not exceed the admissible levels. Comparing to the
previous year, air pollution with sulphur dioxide increased while the level of soluble sulphate,
particulates and carbon monoxide, decreased.
In the city of Bender, no significant changes in air quality were recorded in 2002, comparing to
2001. The air pollution index was 1.29, with variations between 0.91, in October, and 1.77, in
June. The admissible annual average values were not exceeded.
Average annual concentrartion, q/MAC
At the national level, the average annual concentrations of formic aldehide increased, the sulphur
dioxide and nitrogen dioxide decreased and the carbon monoxide and particulate level remained
the same (fig.2.5).
3
2,5
2
1,5
1
0,5
0
Chisinau
Balti
Tiraspol
Rabnita
carbon monoxide
suspended solids
nitrogen dioxide
formaldehide
sulphur dioxide
sulphate
Fig. 2.5. Air pollution in urban areas in 2002.
Bender
fenol
In spatial perspective, the air pollution indexes varied between 0.91 (Bender) and 11.23
(Chisinau). The highest average annual concentrations of pollutants were recorded as follows:
for particulates (1.7 MAC), sulphur dioxide (1.2 MAC), nitrogen dioxide (1.5 MAC) and
formaldehide (2.6 MAC) - in Balti; for carbon monoxide (0.5 MAC) - in Tiraspol; for phenols
(0.8 MAC) in Chisinau and for soluble sulphate (0.07 MAC) in Ribnita.
Singular high concentrations were recorded for: particulates (3.8 MAC), sulphur dioxide (0.9
MAC), carbon monoxide (2.0 MAC), nitrogen dioxide (8.9 MAC), phenols (9.6 MAC) – all in
Tiraspol; soluble sulphate (0.1 MAC) in Ribnita and formic aldehide (1.7 MAC) in Bender.
In terms of annual average concentrations, the situation in Balti seems to be the worst since the
recorded concentrations exceed the quality standards in 4 monitored ingredients out of 5. In
terms of singular („peak”) concentrations, in Chisinau si Tiraspol such values were recorded for
5 ingredients out of the monitored 6; in Balti – for 2 ingredients out of 5; in Bender and Ribnita –
for 3 ingredients out of 5. During 2002, there were 7 cases of extreme air pollution, exceeding
the existing quality standards by more than 5 times (tab. 2.1): 5 cases in Tiraspol and 2 cases in
Chisinau.
Table 2.1
Extreme air pollution cases recorded in 2002: concentrations (qm) exceeding 5 MAC
Pollutant
City
Tiraspol
Chisinau
Month
March
July
July
April
August
November
Nitrogen dioxide
mg/m3
qm/MAC
0,76
8,9
0,48
5,6
0,64
7,2
0,6
7,1
0,43
5,1
mg/m3
0,096
0,077
-
Phenols
qm/MAC
9,6
7,7
-
One of the major consequences of intensive air pollution are the acid rains. Systematic
investigations carried out by the National Institute of Ecology at the Hancesti station in 19982002 revealed that hydrocarbonates dominated in the rain precipitation in that period (on
average, 46.7% from the total amount of analised components). In previous years, the sulphates
dominated in rain deposition (52.6% from total).