Results of the Environmental Health Monitoring System for 2003 are a standard
comprehensive data series that has been obtained in the tenth year of monitoring
activities. They provide important background information for both the national
authorities involved in health risk management and the general public interested
in active health protection. These comprehensive data indicative of environmental pollution
levels and population health status in the Czech Republic are also an information source
for other countries worldwide taking part in commercial and cultural contacts.
The most relevant findings of the Monitoring System are as follows:
Ambient air quality in the monitored cities poses a significant health
risk due mainly to traffic related pollution. Progressive increase in PM10
exposure is evident: in 2003, more than 80 % of the monitored population
were exposed to PM10 levels exceeding the limits. In most of the cities
was proved an increasing trend in NO2 pollution. Concentrations of carcinogens
benzo[a]pyrene and benzene exceeded the limits in most of measuring stations
on a permanent basis.
Results of air mutagenicity monitoring have shown upward trend since 1997
when the monitoring started.
The incidence of cases of treated acute respiratory diseases possibly
associated with short-term high concentrations of air pollutants such as
sulphur dioxide, nitrogen dioxide and ozone has been declining in all age
groups over the last decade. Besides the lower sensitivity of the indicator,
in the possible reasons could be counted the lower frequency of smog situations
or significant concentration decrease of some pollutants. In contrast, the
incidence of all allergic diseases is rising. Multifactorial causes of the
increase in allergic morbidity have not been fully understood yet; chronic
action of the current stable irritating air pollutant levels may play a role
in their emergence.
From the indoor air quality measurement it appears to be most important
the frequent occurrence of relatively high concentrations of formaldehyde
and benzene. The concentrations of particulate matter, nitrogen dioxide
and other VOCs are not considered to be of health importance.
The drinking water quality in the public water supply systems monitored
is of a good standard. The exposure to nitrates through consumption of drinking
water is the most marked; however, it accounts for less than a tenth of the
allowable daily intake for the population of the monitored cities. The nitrate
intake through both drinking water and food consumption for an average
person reaches a quarter of the allowable daily intake. The intake of other
health risk chemicals in drinking water remain under 1 % of the exposure limits.
No case of infectious disease or intoxication possibly associated with
drinking water consumption from the monitored water supply system (supplying
3.5 million population) was reported.
Chronic exposure to chemicals from food consumption for an average person
did not exceed the exposure limits and can be estimated as relatively low.
The intake of some microelements such as calcium, magnesium, copper and
iron is not adequate.
Evaluation based on a recommended food doses model is suggestive of possible
health risks both to children, as a result of higher exposure to contaminants
or healthy supplements (namely from supplemented foods in future), and the
elderly due to low intake of minerals.
There is practically no GMO labeled food product (i.e. product containing
GMO in amounts subject to obligatory labeling) available on the Czech market.
GMOs were detected in a low percentage of samples analyzed. The GMO investigation
results did not show any GMO-related health risk to the population.
The incidence of salmonellosis, the most frequent food-borne infection
of bacterial origin, shows a continual downward trend since 1999. In contrast,
the incidence of campylobacteriosis has been rising over the monitored period.
The estimate of pollutant related cancer risk increase from consumption
of drinking water from the public supply was very low: less than one additional
case of cancer for the whole population of the monitored cities (3.5 million
population). An analogous estimate for the Czech population exposure to chemicals
from food was 65 cases of cancer in 2003. The highest cancer risk from
food is typically associated with PCBs and arsenic.
The contaminant levels in blood, urine, breast milk and tissues of the
Czech population are similar to those reported in developed European countries.
Breast milk contamination with PCBs and pesticides, the residues of which
are most frequently detected in foods of plant origin, i.e. DDT and hexachlorobenzene,
shows a downward trend. This finding is in agreement with the continuously
decreasing detection of PCBs and DDT in dairy products.
Long-term health complaints have been reported by over half of urban population
aged from 45 to 54 years. Locomotor complaints are clearly the most frequent.
One tenth of population of this age group consider their health status as
bad. The differences between the cities in most population health status
indicators and social and environmental rating are statistically significant.
The correlation between socioeconomic factors and health is statistically
significant. The individuals with higher education level and good economic
situation are more likely not to suffer from long-term health problems and
to be satisfied with their health status.
From estimation of oral exposure (exposure from food and drinking water)
to chemicals, it follows that in monitoring network the exposure standards
are derived by an average person in limited measure. Evaluation of inhalation
exposure is complicated by high variability in contaminant concentrations depending
on locality (city vs. countryside), environment (outdoor vs. indoor environment), profession,
lifestyle etc. Evaluation of potential population exposure to mean concentration
levels of pollutants in outdoor air in monitored cities shows that a part
of urban population are exposed on a permanent basis to high levels of hazardous
pollutants exceeding the exposure standards.
It is not possible to determine any safe concentration or exposure standard
for mutagenic and carcinogenic substances in view of their no-threshold effects;
only socially allowable health risks can be established. Therefore, it is necessary
to reduce the population exposure to these chemicals or keep it as low level as
is reasonably possible.
To apply such a strategy where it is most needed, systematic monitoring of
hazardous pollutants in the environment and their health effects and monitoring-based
health risk estimates are necessary. Monitoring of the environment and population
health will be helpful in progressive improvement of pollutant exposure
levels and health parameters which should become comparable with those
reported in the EU countries, and compatible with sustainability of life.