11. RESULTS OF SUBSYSTEM 8: HEALTH RISKS FROM URBAN SOIL POLLUTION |
11.1 Project objectives
The soil in urban agglomerations, contaminated due to the burden on the living environment, can contribute to the increased exposure of the urban population to toxic substances and micro-organisms. Surveys concerning the relationships between soil contamination and health risks have demonstrated that there occurs unintentional intake of dust and filth from the soil by children as well as by adults, in children that occasionally also includes geophagia. Results of research studies have confirmed the increased exposure of inhabitants to chemicals (particularly to toxic metals) from soil and dust intake in areas of contaminated soil. The level of soil contamination in urban agglomerations (agricultural soil is being monitored on a long-term basis) has not been followed up in the Czech Republic. Information is lacking on surface areas that could be a source of excessive exposure namely in the child population. Therefore, the monitoring of urban soil contamination is being introduced into the Monitoring System with the aim of assessing the degree of risks to health occurring from exposure to toxic substances and microbial agents from the soil and dust intake. In view of this, the greatest risk of increased exposure to contaminants from soil is in the child population, the project is focused on kindergarten playgrounds. The project of monitoring the soil in urban agglomerations is one of the tasks included in the National Environmental Health Action Plan NEHAP.
Within the framework of the monitoring of soil contamination, the follow-up of particulate matter fall-out has been introduced as a supplementary information on the origin of the ground-surface soil contamination with chemicals.
The major objectives of the project are:
11.2 Organization of monitoring activities
The pre-project and project stages were divided into several phases:
Phase I - elaboration of the project and standard operational procedures,
including their verification - year 2000;
Phase II - pilot study - year 2001;
Phase III - monitoring of urban soil contamination at five-year intervals -
beginning year 2002.
In the year 2000, a project of a pilot study of the urban soil contamination monitoring in three Czech cities - Olomouc, Ostrava, and Karviná was elaborated. The standard operational procedures (SOPs) for the taking, storage, and transport of soil samples and particulate matter fall-out, for the analytical determination of selected metals and organic substances in soil and of metals in PM fall-out was worked out. SOPs for microbiological determinations of selected microorganisms and for the parasitological investigation of soil were elaborated.
In 2000, with the aim of verifying SOPs, preliminary samplings and analyses of soil were made in ten kindergartens in Olomouc and in ten in Karviná. Samples of the ground-surface soil were taken in selected kindergartens on sites of the most frequent stay of children, and analysed as pooled samples from five sampling point each. Soil samples for the determination of PAHs were taken in the period August-December 2000; for microbiological and parasitological analyses they were taken in September and October 2000.
11.3 Factors monitored
In 2000, in the ground-surface soil of selected kindergartens were monitored:
11.3.1 Toxic metals and trace elements
Lead levels in ground-surface soil in Karviná were in the range of 30.8-50.4 mg/kg, those of arsenic 6.2-11.0 mg/kg, and cadmium 0.4-0.6 mg/kg; in Olomouc the levels detected were in the range of 29.0-96.0 mg/kg for lead, 4.9-11.0 mg/kg for arsenic, and 0.4-0.6 mg/kg for cadmium. The levels of toxic metals and trace elements found were compared with limit values recommended in the draft of the Ministry of Health Decree “On health requirements for the location and operation of sand pits, recreational, sports and other playgrounds and their facilities”. In Karviná, the level of lead was exceeded in one kindergarten, that of arsenic in two, cadmium in all ten, mercury in one, beryllium in eight, and that of thallium (according to Beneš S, Pabianová J: Natural content, distribution, and classification of elements in soils. Agricult. Univ. Prague, 1986) in six kindergartens. The levels of copper, chromium, and vanadium were lower than their recommended limit values in all cases. In Olomouc, the lead content was exceeded in three kindergartens, that of arsenic in two, cadmium in two, mercury in three, and copper in one kindergarten. The levels of chromium, beryllium, vanadium, and thallium were lower than the recommended values for non-contaminated soil, in all cases regarding the Olomouc kindergartens. The metals content found in the ground-surface soil are presented in Table 11.1.
11.3.2 Polynucleus aromatic hydrocarbons
The assessment included those polyaromatic hydrocarbons (PAHs) for which there has been recommended a limit value in the draft of the Ministry of Health Public Decree “On Health requirements for the location and operation of sand pits, recreational, sports, and other playgrounds and their facilities”. In Karviná, only the naphthalene content was below the recommended limit value for uncontaminated soil, in all the ten kindergartens under follow-up. The levels of benzo(a)pyrene exceeded the recommended limit value in eight kindergartens, that of phenanthrene in six, and that of benzo(a)anthracene in two kindergartens. In the soil samples from all ten kindergartens in Karviná analysed, the recommended limits for anthracene, fluoranthrene, chrysene, and the sum of PAHs have been exceeded. In the samples analysed from all the kindergartens in Olomouc, the levels of benzo(a)pyrene, anthracene, fluoranthrene, chrysene, and the sum of PAHs exceeded the recommended limit values for uncontaminated soil. The levels of benzo(a)anthracene exceeded the limits in three kindergartens, those of phenanthrene in nine, and of naphthalene in two kindergartens. Two kindergartens with above-average levels of all the polyaromatic hydrocarbons have been determined. The aggregated results are presented in Table 11.2.
11.3.3 Indicators of microbial contamination
From the results presented in Table 11.3 it follows that limit concentration values of faecal pollution indicators according to Decree No. 464/2000 of the Ministry of Health (Supplement No. 8 for the evaluation of faecal pollution of playgrounds) were exceeded in on one-half of a total of twenty kindergartens under follow-up. In seven kindergartens, the limit value of 102 CFU/g of dry matter for thermotolerant coliform bacteria has been exceeded, and likewise in seven kindergartens contamination with enterococci greater than 102 CFU/g dry matter has been found. Contamination by moulds and yeasts in 14 samples (70 %) was in the range of 104-105 CFU/g dry matter, in five samples (25 %) in the range of 105-106 CFU/g dry matter, and in one (5 %) more than 106 CFU/g dry matter.
Analyses of soil samples have not demonstrated the presence of salmonellae or pathogenic geohelminth ova in any case.
11.4 Partial conclusions
In 2000, a pilot study project was prepared as well as an associative study for soil contamination monitoring in urban agglomerations in 2001. There has been initiated the verification of standard operational procedures for sampling, storage, and transport of ground-surface soil samples, for the determination of elements in soil and PM fall-out, for the determination of polynucleus aromatic hydrocarbons in soil, and for microbiological analyses. A set of preliminary results of soil samples analyses from twenty kindergartens in Karviná and Olomouc has been obtained.
In Karviná, the limit values for uncontaminated soil recommended in the draft of the Ministry of Health Decree “On health requirements for the location and operation of sand pits, recreational, sports and other playgrounds and their facilities” have not been exceeded in copper, chromium, and vanadium. Nowhere in Olomouc have those limit values been exceeded as regards chromium, beryllium, and vanadium. As far as the other metals monitored are concerned, in some kindergartens higher levels than their recommended limit values have been found.
On the basis of results on PAHs burden of the kindergarten soil yet obtained, it can be stated that the PAHs levels exceed the recommended limits for uncontaminated soil. Except for naphthalene in the kindergartens of Karviná, the levels of PAHs monitored exceeded the recommended limit values in both cities. The levels of the sum of polynucleus aromatic hydrocarbons, anthracene, fluoranthene, and chrysene were exceeded in all the kindergartens under follow-up.
As of yet, the relationships between microbiologically contaminated soil and the incidence of any specific illness in children have not been sufficiently described in the literature; the microbiological pollution commonly occurring on children’s playgrounds has not even been studied in detail. Therefore, in the present phase it is not possible to estimate the health risk following from microbial contamination of the soil. From a comparison of the values found in the soil of kindergartens with limit values, it can be stated that, in some of the indicators, the limits have been exceeded in the soil samples from half of the kindergartens under follow-up.
Table 11.1 Upper soil metal concentrations in Olomouc and Karviná nursery school gardens
|
ELEMENTS [mg/kg] |
||||||||
Pb |
Cd |
Cu |
Cr |
As |
Be |
V |
Tl |
Hg |
|
OLOMOUC |
|||||||||
Median |
37.4 |
0.3 |
29.8 |
24.0 |
7.8 |
0.8 |
30.3 |
0.21 |
0.2 |
Mean (arithmetic) |
45.7 |
0.3 |
29.1 |
24.6 |
7.8 |
0.8 |
30.0 |
0.20 |
0.3 |
Maximum |
96.0 |
0.4 |
48.0 |
31.0 |
11.0 |
1.2 |
39.7 |
0.26 |
1.1 |
Minimum |
29.0 |
0.2 |
17.4 |
21.1 |
4.9 |
0.5 |
21.5 |
0.15 |
0.1 |
Content in nonconta- |
50.0 |
0.3 |
45.0 |
85.0 |
10.0 |
1.5 |
80.0 |
0.25* |
0.3 |
KARVINÁ |
|||||||||
Median |
41.0 |
0.5 |
19.2 |
48.8 |
8.2 |
1.7 |
48.7 |
0.45 |
0.1 |
Mean (arithmetic) |
41.7 |
0.5 |
18.6 |
50.7 |
8.4 |
1.8 |
48.9 |
0.46 |
0.1 |
Maximum |
50.4 |
0.6 |
20.6 |
59.8 |
11.0 |
2.5 |
60.8 |
0.88 |
0.3 |
Minimum |
30.8 |
0.4 |
15.1 |
38.4 |
6.2 |
1.2 |
33.0 |
0.22 |
0.1 |
Content in nonconta- |
50.0 |
0.3 |
45.0 |
85.0 |
10.0 |
1.5 |
80.0 |
0.25* |
0.3 |
+ according to the proposal of the Decree of Ministry of Health
on public health requirements for the location and operation of sand pits,
recreational, sports grounds and other playing sites and their facilities.
* according to Beneš S., Pabianová J.: Natural element contents, distribution
and classification, VŠZ - Praha, 1986
Table 11.2 Upper soil PAHs concentrations in Olomouc and Karviná nursery school gardens
|
PAH [mg/kg] |
||||||||
Naphta- |
Phenan |
Anthra- |
Fluoran- |
Pyrene |
Chrysene |
Benzo(a)- |
Benzo(a)- |
Total |
|
OLOMOUC |
|||||||||
Median |
0.07 |
0.48 |
0.12 |
1.55 |
1.19 |
0.58 |
0.60 |
0.75 |
8.06 |
Mean (arithmetic) |
0.26 |
1.83 |
0.39 |
5.21 |
3.80 |
1.71 |
1.58 |
2.25 |
25.84 |
Maximum |
1.90 |
12.00 |
2.80 |
28.00 |
20.00 |
9.20 |
6.80 |
12.00 |
125.00 |
Minimum |
0.03 |
0.08 |
0.04 |
0.20 |
0.16 |
0.12 |
0.14 |
0.15 |
1.97 |
Content in nonconta- |
0.10 |
0.10 |
0.01 |
0.10 |
* |
0.01 |
1.00 |
0.10 |
1.00 |
KARVINÁ |
|||||||||
Median |
< 0.05 |
0.16 |
0.04 |
0.43 |
0.42 |
0.14 |
0.25 |
0.27 |
2.37 |
Mean (arithmetic) |
< 0.05 |
0.22 |
0.11 |
1.00 |
0.95 |
0.27 |
0.53 |
0.48 |
5.09 |
Maximum |
0.07 |
0.61 |
0.57 |
4.64 |
4.61 |
1.21 |
2.39 |
1.82 |
20.52 |
Minimum |
< 0.05 |
0.04 |
0.02 |
0.16 |
0.14 |
0.05 |
0.09 |
0.10 |
0.95 |
Content in nonconta- |
0.10 |
0.10 |
0.01 |
0.10 |
* |
0.01 |
1.00 |
0.10 |
1.00 |
+ according to the proposal of Decree of the Ministry of Health
on public health requirements for the location and operation of sand pits,
recreational, sports grounds and other playing sites and their facilities.
* not proposed the appropriate limit
Table 11.3 Microbiological and parasitological indicators of soil pollution in Olomouc and Karviná nursery school gardens
|
Distribution of the schools according to upper soil microbiological contamination |
|||||
< 101 KTJ |
< 102 KTJ * |
< 103 KTJ |
< 104 KTJ |
< 105 KTJ |
> 105 KTJ |
|
OLOMOUC |
||||||
Thermotolerate colif. bacteria |
- |
7 |
3 |
- |
- |
- |
Enterococci |
- |
7 |
2 |
1 |
- |
- |
Yeasts and fungi |
- |
- |
- |
- |
4 |
6 |
KARVINÁ |
||||||
Thermotolerate colif. bacteria |
- |
6 |
3 |
1 |
- |
- |
Enterococci |
- |
7 |
- |
3 |
- |
- |
Yeasts and fungi |
- |
- |
- |
- |
10 |
- |
The findings of Salmonellae and geohelminths ova in upper soil samples were negative in any case.
* Public health limit value for thermotolerant coliform bacteria and enterococci set in Regulation No. 464/2000 of the Ministery of Health, suppl. No. 8 - evaluation of playing areas fecal pollution.