Lead in the Environment and Children’s Health in Russian cities

Boris Revich. Center for Demography & Human Ecology of the Institute for Forecasting, the Russian Academy of Sciences, 47, Nakhimov’s Av., Moscow, 117 418, Russia. E-mail: revich@unix.ecfor.rssi.ru.

Abstract

Main sources of lead emission are motor vehicles, non-ferrous metallurgy enterprises and hard household waste. Lead contents in the children’s blood in city with metallurgical plants is 9 – 13 mg/100 ml, in other cities it is 7 – 8 mg/100 ml. Notable changes of various parameters of nervous and psychical status of a child are observed for the examined children with elevated lead content of blood. Children demonstrate the greater frequency of high anxiety state, changes in higher psychical functions and other neurodevelopmental changes. Biokinetic model of ЕРА (USA) was used to estimate the lead contamination hazard for children of Russia as a whole. It was determined that the lead content in blood for approximately 2,3 million children living in 120 cities and towns may exceed the standard level of 10 mg/dL, and this is accompanied by respective changes in children's nervous and psychical development and behavior.

Introduction

The government of the Russian Federation began to give serious attention to lead contamination in the early 1990s, part of a broader policy response to the more general crisis of environmental pollution and degradation. In the 1970s, leaded gasoline had been prohibited in Moscow, Leningrad, and major cities and resort areas in the Soviet Union. But these regulations were never systematically enforced and the production and use of leaded gasoline continues.

The Report on Lead Contamination of the Environment in the Russian Federation and its Effect on the Health of the Population, prepared by the Ministry of Environmental Protection and the U.S. AID, was published in 1998. The report generalized data on lead pollution of the environment (White Paper, 1997).

Atmospheric lead pollution is still a major problem in Russia. In more than 30 cities, the level of lead in ambient air exceeds the current Russian air standard (the maximum acceptable concentration is 0.3 mg/m cubed). Approximately 4000 tons of lead is emitted into the air each year. The primary source of ambient lead emissions is motor vehicles. The main stationary sources of lead emissions are non-ferrous metals industries, including lead and copper smelters, and facilities manufacturing lead batteries. Factories producing leaded glass or lead-glazed ceramics are other sources of lead pollution.

Soil contamination is another significant source of lead exposure. Elevated levels of lead have been found in the soils of 120 cities. In cities with metallurgical industries the concentrations of lead in soil reaches levels ranging from 1000-2000 mg/kg. Soil contamination of agricultural lands is less common, although lead along roadways in close proximity to farms or community gardens is especially hazardous.

Hard household waste consisting of used car batteries, metal food containers soldered with lead and other items are also a serious source of environmental lead pollution in Russia. An estimated one million tons of lead is currently contained in used car batteries alone. They can be found dumped on the ground, in parking lots and garages and in many other locations. Every year this amount grows by approximately 50,000-60,000 tons.

Drinking water may be a significant source of exposure and deserves further attention. Data on lead content in drinking water is scarce, however. Most samples that have been taken indicate levels below the maximum acceptable standard of 0.03 mg/l. Nevertheless there is concern that pipes in the water distribution system may be leaching lead into drinking water. The Russian Ministry of Health plans to introduce monitoring of lead and other toxic substances through tap water samples.

Despite the substantial volume of data on lead environmental pollution, data on lead content in the children’s blood and on its neuropsychological damage to exposed children are rare. The studies on these issues have been conducted in several Russian cities since 1995 г.

Methods

Samples of human tissues (blood, hair) and plant were analyzed by FAAS using microcolumns with DETATA-sorbent for on-line flow sorption preconcentration of lead (FI-FAAS). "Quant-AFA" spectrophotometer (Russia) combined with PC-controlled flow-injection system was used. All samples for analysis were digested by mixture of chloric and nitric acids before the lead measurements. The detection limit for lead by the method of direct atomic absorption analysis equals 0.5 mg/mL. Detection limit for lead in the method of FAAS with on-line flow sorption preconcentration was 0.005 mg/ml.

The accuracy of the analytical methods that were used was determined by the analysis of international and СDС standard reference materials.

The Biokinetic or IEUBK model, a software package of linked computer programs developed by the USEPA, was used for calculation of lead content in blood.

Methods for evaluating neuropsychological development in children.

The assessment of anxiety was made with the use of children’s version of the Manifest Anxiety Scale (CMAS) developed on the basis of the Manifest Anxiety Scale for adults The above test was adapted for use in Russia by Prof.A. Prikhozhan,

Results

Lead in blood.

Results of tests. Lead content in children’s blood was assessed for the cities where major sources of pollution were copper-melting enterprises (Belovo and Krasnouralsk) and battery manufacturing enterprises (Saratov and St. Petersburg). In the city of Belovo (Eastern Siberia) lead concentrations in soil ranged from a relatively safe low of 30 mg/kg to an alarming 3,000 mg/kg. The mean blood lead level of the 91 children tested was 8.5 mg/dl (0.5 - 39 mg/dl). Forty-two percent of children tested had levels exceeding 9.9 mg/dl. Ten percent of tested children had levels above 14.9 mg/dl. (Revich et al.,1998).

In Krasnouralsk (Middle Ural), the city where one of the oldest copper-smelting plants in Russia is located, lead dust inside buildings ranged from 31 to 168 mg/sample, and the lead content of soil ranged from 40 to 790 mg/kg. The average lead content of sand from children’s playgrounds was 290.3 (42.9 – 790.8) mg/kg. Although there were no available data on concentrations of lead in food, food products grown on contaminated soils in the city are also believed to be a major source of exposure (Privalova et al., 1998).

Influence of lead pollution coming from battery manufacturing plants was assessed in St. Petersburg and Saratov. In 1913 a factory producing storage batteries was built on the outskirts of the city. For 583 children living near the plant that were tested, the mean blood lead concentration was 13.9 mg/dl, and 42 percent of children had levels exceeding 9.9 mg/dl. 24 percent of the children tested in Saratov had blood lead levels over 9.9 mg/dl. (C. Rubin et al., 1997)

Results of model prediction. In 120 Russian cities, 44 percent of children may have blood lead levels that exceed the CDC, a recommended safe level of 9.9 mg/dl, and a total of nearly 2.4 million children may have been harmed through lead contamination More specific applications of the model in several cities with large lead-related industries (Belovo and Gus-Khrustalnii) have compared predicted blood lead levels – based on contaminated soil, dust at homes and schools, and lead-contaminated foodstuffs – with actual blood lead data from samples of children.

The mean blood lead level children in Belovo, according to the biokinetic model, ranged from 9.0 to 11.7 mg/dcl. These numbers correspond well with lead level test results set above. In Gus-Khrustalnii, where the main source of lead emissions is the production of glass and crystal, resulting in 39 tons of lead per year released into the environment, 2800 children have blood lead levels exceeding 9.9 mg/dl.

Model predictions and estimates of population distributions from blood lead data generally correlate well. The biokinetic model is proving to be a useful tool in identifying populations of children at risk, and identifying primary pathways for lead exposure.

Lead in hair.

The permissible level of lead in hair is 8-9 mg/g. Systematic research to determine the accumulation of lead in human hair has been carried out in various Russian cities since 1980 using modern tools. During the last years, research has been done on about 8,000 types of hair from children living in cities with various sources of lead discharges. Among the juvenile population exposed to increased concentration of lead, the highest accumulation levels have been observed in areas of metallurgic and car battery plants location, in the cities of Vladikavkaz, Kursk, Karabash, Krasnouralsk, Kyshtym, Saratov, Cheliabinsk, as as the zone suffered from Chernobyl nuclear station catastrophe.

Thus, in city of Karabash (Middle Urals), the main source of contamination is a copper-smelting plant dating from 1910. In recent years emissions had reached a peak of 2100 tons per year. Extremely high levels of soil contamination remain (levels range from 1500 – 2000 mg/kg) are regularly detected in the city. Vegetables grown by the local population from these soils contained 1.5 – 2.5 mg/kg of lead. Lead content in the hair of 32 percent of children that were surveyed exceeded the danger level of 9 mg/g. Such high levels may lead to changes in neuropsychological development.

It seems necessary to assess also the lead level in blood and hair of children in the regions suffered from Chernobyl nuclear station catastrophe, considering the huge amount of lead that was used during its liquidation.

Neuropsychological status.

Level of anxiety among children in Belovo is higher than in other cities. In city of Lipetsk, where level of lead in hair of children exposed to pollution from a metallurgy plant, reached 7.5 mg/g (level in control group – 3.0 mg/g), certain changes in mental development were assessed. Following tools, covering different CNS Domains, were used: Tests of Memory and Learning (TOMAL), Child Development Inventory (CDI), Behaviour Scale. Pre-, perinatal (maternal and father’s ages, birth weight, alcohol, medications, smoking during pregnancy), social (income, living conditions, maternal education) and health (Health group, encephalopatia, anemia) factors were studied (Iltchenko et. all, 1999).

Discussion

Lead pollution in Russia is less alarming than in other world industrial countries, since there are less cars, and usage of lead-containing paints for inside works are prohibited in Russia. However, the lead contamination became an acute problem for the cities where major lead polluting enterprises are located.

Mean lead level in tested children’s blood in Russia is rather close to assessments made in other cities with high lead contamination in the environment, such as Mexico - 9.9 mg/dcl (Romien et al., 1995), Budapest - 9 mg/dcl (Bitto et al., 1997), Katowice (Poland) - 7.6 mg/dcl (girls), 8.3 mg/dcl (boys) (Zejda et al., 1995), Pribram (Czech Republic) - 11.4 mg/dcl (Cikrt et al., 1997).

By present time, the State Program on Reduction of Lead pollution is developed. The program includes mandatory examination of children, development of standardized methods of assessment of lead content in blood and better informing people about lead hazard.

Data on the extent and severity of lead exposure among children living in these cities, together with better information on the actual sources of contamination, are being used to develop targeted interventions.

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