THE PROBLEM OF SOIL POLLUTION IN RUSSIA
AND ASSOCIATED HEALTH PROBLEMS

Chernih A.M., Solodoukhina D.P., Osusu Shell Oghenekevwe

Kursk State Medical University, Kursk, Russia

Department of General Hygiene

Delta state institute of continue education, Warri, Nigeria

1. Soil pollution in the Russian Federation and associated health risks: overview of the problem.

Health of a human is influenced by a large number of factors which include; political, economic, social, ecological, psychological factors. Experts from the WHO estimated that 50-52% of health depends on individual life style, 20-22% on heredity and genetics, 18-20% - environmental conditions, and 7-12% are determined by health care system. Some researchers suppose that 80% of the modern diseases are related to the negative effect of the environment.

Environmental safety is one of the major factors of population health. In many regions of Russia there is an alarming ecological situation that is also determined by the sanitary condition of the soil. Soil pollution can be the source of secondary air pollution, water, agricultural products and fodder. Different from other mediums, there is no possibility of rapid purification of the soil, thus absorbed chemicals can be preserved there for many years. Soil pollution in industrial areas can achieve a critical level that presents a real threat to the health of people. Though in the past years in majority of Russian cities there is reduction of harmful substances emission, still a lot of chemical toxicants are detected in the air, soil, food products etc. This shows that problem of chemical safety is one of the most important factor for preservation of health of all people, not only of those who are employed in special industries.

Russian Federal Center of State Sanitary Epidemiologic Control provides sanitary-hygienic monitoring of soil pollution by detection of major chemicals polluting the soil, measuring intensity of pollution, performing factorial analysis to find the reasons for contents changes. By the official report of this Center the leading pollutants for the soil of Russia in the past years have been heavy metals like lead, cadmium and zinc. Copper, nickel, chrome and mercury are less common and usually determined by the certain industrial production."

Complex investigations conducted in Moscow by the leading national institutes (headed by the National Research Institute of Human Ecology and Environmental Hygiene named after A.N. Sisin of Russian Academy of Medical Sciences) detected 19 soil anomalies of complex multi-element contents that occupy 29% of the city area. Everywhere there were present of lead, copper, zinc, tin and silver. In some areas there were elements released by certain factory. The chemical pollution is aggravated by biological pollution. There were findings of high microbial and viral contamination of soil and sand in sand-boxes of children institutions. We must understand that the higher the chemical pollution of the soil the more the role of the soil as a transmitting factor of parasitic and infectious diseases. Pathogenic enterobacteria and helmints are more resistant to chemical soil pollution than normal soil microorganisms - E. coli antagonists.

In the year 2003 in the Russian Federation the number of soil samples not satisfying the hygienic standards by sanitary-hygienic parameters increased from 12.2% (2002) to 12.4%. In12 regions of Russia the proportion of samples with elevated contents of dangerous pollutants was 2 -4.3 times higher than average in the country. Six regions (Samara, Tula, Chita, Sverdlovsk, Khabarovsk regions, Primorskiy kray) had 29.6 to 53,4% of such samples that was 11-36% higher than in the year 2002. Particularly dangerous is increasing pollution of build-up areas with heavy metals. In industrial areas the proportion of soil samples with increased amount of heavy metals achieved 67.3% that is 2.3-5.7 times higher than the average in Russia. The worst situation was in the Far East, Ural, and Siberia.

In the year 2003 there was increase in number of samples with high contents of mercury from 0.4 to 0.6% (Sverdlovsk, Irkutsk regions, Primorskiy kray), cadmium - from 2.1% to 2.3% (Moscow, Vologda, Chita, Sverdlovsk regions, Primorskiy kray).

Table 1

Shows the list of regions with theproportion of soil chemical pollutants
in the inhabited areas between 2000-2002

Soil of rural areas is mainly polluted by chemicals used in agricultural sector. Ecologo-toxicological expertise assessment of the soil contents in 1998 by the Ministry of Agriculture of the Russian Federation showed that 1.4 mln

Hecter of the country are polluted by heavy metals.

Table 2

Shows the remained amount of pesticides in the soil samples above TLVin Russia in the year 2000

In the past years the used of organochlorides ,partically DDT have been reduced in the country. But the problem of their storage and utilization has remained unsolved. DDT was excluded from the list of chemicals eligible for agricultural use in 197, but in 1988about 126 tons of DDt was used for prevention of some edemic diseases.

A research in south of Russia (Krasnodarsky kray) showed that breast milk of women living in that area contained DDT and its metabolites. There are also more reproductive system disorder among the inhabitants of this region.

Despite the fact that the there is a reduction in the use of pesticides in the past years we must consider their high toxicity and ability to remain preserved for a long time in the environment.

The potential effects associated with exposure to organoclorine pesticides include neurobehavioral disorders, cancer and spontaneous abortion.

The WHO experts emphasize on the significant relationship between the level of toxicants in the soil and food and population health. Epidemiological studies showed that lead can enter the human body with food, soil and air.

2. Contaminants and their effect on health.

There is a direct correlation between increased concentration of toxic elements in the soil and occurrence of pathological conditions. For instance, in Tula region the association between chromium exposure and malignant neoplasm (r = 0.7), diseases of endocrine system (r = 0.6) and genitourinary tract diseases (r = 0.6) was detected. In Novgorod region, association between lead exposure and incidence of neurological and musculoskeletal diseases in children, neurological diseases, diseases of blood and neoplasm in adults was detected. Zink exposure was detected as a factor associated with diseases of the gastrointestinal system and skin. '

Generally, in areas with high level of soil pollution there is increased number of children who have frequent cases of diseases of different classes, reproductive disorders in women like infertility, premature delivery, miscarriages, and newborns with low birth weight.

Heavy metals detected in biological mediums are particularly common in children population. In the town of Karabash (Chelyabinsk region) 60.3% of children had increased level of lead in the hair. Systemic exposure to heavy metals determines certain physiological changes, which have clinical manifestation in the form of neuralgia, cephalalgia, blood changes, liver and skin diseases.

Another aspect of soil pollution in Russia is the contamination of land by oil and oil products. At all stages of oil fields development from boring to industrial manufacturing there can be accidental pollution of the environment because of pipeline breaks, oil storage damages, or human mistake. Annually out of 300 mln tons of the oil extracted in the country, 1.5% and more is lost during extraction, transportation or storage that is around 4.5mln tons per a year. Today about 800 thousand of hectares of the soil need to be cleaned from the oil pollution. There is a special concern on this problem because in the present system of epidemiological monitoring oil is not included in the number of detected major pollutants. There is also no research on the role of oil-polluted soil on health of people.

3. Kursk region as an area of high electromagnetic field and intensive agricultural production.

Electromagnetic pollution of the environment is another issue which becomes a large-scale problem in Russia. This problem is particularly important in large cities, which have many various sources of electromagnetic fields (EMF) and large density of population. In the last ten years with the rapid development of telecommunication and electronics, the intensity of EMF has also increased. Electromagnetic radiation is also used for therapeutic purposes in medical institutions (like micro-wave therapy, diathermia etc). For these reasons the problem of EMF and their possible negative effects on health makes more and more concern for physicians, as well as for ecologists, hygienists, physicists, biologists. According to the literature the most sensitive to EMF are immune, nervous, endocrine, and hemopoietic systems. Irreversible changes in the human organism are observed even at short-term repeated exposures to EMF of low intensity. For multiple repetitions of EMF radio-waves biological effect is cumulated. However, the variety of clinical manifestations and absence of specific characteristics in changes of health condition make it very difficult to distinguish EMF as a health hazard or risk factor for certain pathological conditions. Experimental studies showed the potential negative effects of EMF on animals, namely it can lead to death of embryos or malformations, promote development of neoplasm like cancer of mammary glands in rats. There is weak association between exposure to EMF and biological effects, absence of dosage effect give the reason to call EMF promoters but not inducing or causal factors of cancers. The latter can be viruses, pesticides, solvents and other physical or biological agents.

Ecological and hygienic aspects of electromagnetic fields are not well investigated. It is reasonable to study variation of naturally existing geomagnetic field particularly in the regions of magnetic anomalies. The research has shown that there are several magnetic anomalies on the Earth where geomagnetic field is different from other areas on average by 10%. In Russia the two largest ones, are Angaro-Ilimskaya and Kursk magnetic anomalies (KMA). Horizontal component of GMF induction on the territory of KMA is rising, 80 000 nT, vertical component is up to 170 000 nT, that is 5-6 times more than in other areas. KMA is spreading from the north-west to the south-east from the Baltic Sea to the Azov Sea, the width is 250 kms, the area occupied is around 160 thousand square km2, and it covers 12 regions in Russia and Ukraine (Smolensk, Kaluga, Bryansk, Oryol, Kursk, Berlgord, Voronezh, Sumi, Kharkov, Donetck, Lugansk, Rostov regions). Maximal intensity of anomalous GMF was recorded in the territory of Kursk region in the town Jeleznogorsk, that allows to consider it as a center of KMA and its anomalous geomagnetic field is a natural risk factor for health. Geophysical reason for KMA is the enormous mass of iron quartzite in earth deposits, magnetization of which under the influence of normal GMF creates the additional field called anomalous. With increase in sun activity the variation of GMF is dramatically increasing. Yu. A. Grigoriev proved that GMF is a risk factor for people working in shielded building. Several authors increase resistance of shigella Zne to antibiotics in anomalous regions.

The incidence of acute gastrointestinal infections in the of KMA is 2-4 times higher than in Kursk, where the intensity of GMA is 4-5 lower.

We raise the problem GMF and their effect on health because these factors in association with other environmental pollutant to posed higher risk on health. Experimental study of combined effect of EMF and pesticide-chlorpyriphos revealed interaction and synergistic effect on mortality of rats. For this reason attention should be paid to the use of agricultural chemical in the area of KMA. legal regulation should target the use of pesticides in area of KMA because GMF is a natural non-modifiable factor.

From the year 1995 the average amount of pesticides per 1 hectare of cultivated land has decreased gradually and in the year 2002 it was 0.24 kg or 0.11 kg of the active substance. This is obviously a positive trend that shows reduction of ecological danger for the population health and environment.

According to data in Kursk regional center responsible for environmental monitoring in 2001 about 11.3 thousand hectares of agricultural lands were contaminated with pesticides, including 10.0 thousand hectares of ploughed fields (from which 0.9 thousand hectares are moderately dangerous) and 1.3 thousand hectares of perennial plantings (from which 0.2 thousand hectares are moderately dangerous). In the last six years the amount of polluted lands has increased. The major chemicals -pollutants are simazin, bayleton, and DDT. One of the areas famous for fruit production (Oboyan) has 89% of land polluted with the mentioned chemicals. The remained amount of DDT in the soil was 2.5-2.7 times higher than TLV in spring and 1.9-2.2 times higher than TLV in autumn.21

Though the use of pesticides in Kursk region in the last years has decreased, we observe increase in the list of used chemicals. There must be a continuous strict monitoring of the use of agrochemicals considering the larger participation of private commercial organizations supplying agrochemicals. In the conditions of anomalous geomagnetic fields in the region more attention should be pay to environmental safety important for population health.

4. Conclusions and recommendations for improvement of the situation.

The existing legal basis in Russia is not enough for effective control and organization of monitoring system of soil pollution and its risk assessment. Today there is justification of threshold limit value for more than 500 substances, the majority of which are pesticides and only 39 items are industrial chemical pollutants. Absence of legal norms or their under-development leads to the situation that some of the ministries and administrative departments set their own levels of TLV for different substances. So, one of the major directions in research for preservation and protection of soil should be defining of chemical substances in the soil in concentrations that are safe for health.

Recommendations

There should be:

• improvement of ranking system of chemical pollutants of soil by their toxicity and threat with consideration of similar studies in the developed countries.

• analysis and reconsideration of legal normative basis and harmonization of TLV with international standards.

• Development of norms for the major pollutants like oil, heavy metals, etc.

• Development of methodology of prognosis of possible changes in health under the influence of soil pollutants considering the level of soil pollution;

• investigation of quantitative relationships between soil pollution and response of the dependent factor in the chain of effect (plant, air, water, microorganisms, human);

• improvement of calculation techniques of justification of TLV of different chemicals and their combinations in the soil;

• development of methodology of investigation of health status of people as the integral measurement of soil effect, polluted by chemical and biological factors

• standardization of methods used for detection of chemical substances in the soil.

• improvement of the national and regional law on soil preservation as the basis of ecological safety and public health.

Preservation of soil safety is one of the major ecologo-hygienic tasks in the Russian Federation. In order to solve it there should be a combined efforts of many professionals -- epidemiologists, hygienists, occupational therapists, agricultural chemists, public health specialists. There must be a national policy aimed at development of long -term sustainable programs to solve ecological and hygienic problems of soil pollution in the country before it led to catastrophic consequences.