Longitudinal Assessment of Exposure and Health Effects in Kindergarten Children From

Longitudinal assessment of exposure and health effects in kindergarten children from

Saxony-Anhalt, Germany P. Krumbieger , S. Miethe*, O. Herbarth", M. Rehwagen",

U. Rolle-Kampczyk*, U. Franck*, H.-J. Stark**, G. Fritz', W.-E. Kalteich'', C. Ettrich' & F. Wege"

"Dep. Human Exposure Research andEpidem., Dep. Analyt.

"Redevelopment Ass. Network Mansfeld, Germany

Abstract

The health status of 2 complete kindergarten groups of 3-year old children from two small towns, Hettstedt (n = 25) and Wippra (n = 26) was assessed every six months for 3 years. The kindergartens are located at varying distances from disused copper and lead smelters. Different parameters were analysed in order to characterise various air pollution influences. A parent-completed questionnaire gave information on the child's and family's medical history, residence, living conditions and neighbourhood. During the 3 pre-school years, attention was primarily focused on the children's individual development. 700 pre-school children from Leipzig and the surroundings served as a reference group for some of the parameters

Results: Mean delta-ALA values were higher for the children from Hettstedt compared to Wippra. The effect data were correlated with the lead contamination of airborne dust collected from the former smelter's grounds and from the kindergarten's playgrounds, as well as with the lead burden in the teeth. All data were higher in Hettstedt. Moreover, the liver detoxification capacity was slightly better in Wippra. The results suggest that more than one parameter needs to be monitored several times to observe exposure-related health effects in comparison studies of small groups from different localities.

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I Introduction, methodology

Accompanying substances of airborne dust (in particular heavy metals but also certain organic compounds) are suspected of being harmful to human health, especially among young people as a risk population. Another source of potential air pollution health effects are airborne volatile organic compounds (VOC). Because of the relatively low loads and the correspondingly small effects, it is difficult to estimate correlations between pollution and effect under normal living conditions. Although the measuring methods to be used must be non-invasive and non-distressing for the probands, they must nevertheless be as sensitive and specific as possible and provide an accurate reflection of the situation. In order to tackle for this methodological problem, we decided to use the following parameters: - To choose a rather small but uniform study group of children in a small,

distinct, heavily polluted region with all the children of this population participating; - To compare this population with a corresponding complete group living

in a relatively weakly polluted region. The first group were all 3-year old children of a kindergarten (n = 25)

near the former copper-lead smelter and waste dumps in the small town Hettstedt, Saxony-Anhalt, and the second a corresponding complete kindergarten group (n = 26) from Wippra, a climatic health-resort in the

Harz valleys 15 km bee-line WNW away from Hettstedt. - To offer and use only non-invasive and non-distressing investigative methods acceptable to all the parents of the children;

_ To include several methods for different parameters and piece the results together like a mosaic to produce a complex picture.

The methods used for exposure estimates were: - estimated personal exposure to airborne sedimentation dust and heavy metals thereupon

— at the smelter grounds, - at the kindergarten playgrounds in front and behind the building, - inside the building; - estimates of airborne particulate matter and heavy metals thereupon;

- estimates of house dust collected in the children's homes and in the kindergarten rooms by vacuum cleaner; - estimated personal exposure to VOCs (Herbarth [1]) in the children's

private bedrooms and in the kindergarten dormitories; - assessment of the lead burden via the milk-teeth (Franck [2]); - assessment of the VOC burden via VOC metabolites in the urine.

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The methods for health effect assesssments were:

- fundamental medical examination; - complete blood count (CBC);

- investigation of the liver detoxification capacity (Krumbiegel [3]); - investigation of the urinary delta-aminolaevulinic acid excretion; - examination of psychological development.

Another methodological point was the longitudinal nature of the study, with most of the versatile investigations being repeated every six months for three years.

The practical investigations were accompanied by a detailed questionnaire completed by the parents once at the beginning and once at the end of the study. The answers gave information on the child's and family's medical history, residence, living conditions, neighbourhood etc.

The main focus during the three pre-school years was to follow up the individual development of the children under two sets of different environmental conditions. Is there a serious health effect in the case of the children from Hettstedt, who are believed to be more severely burdened than the children from Wippra ?

2 Results

2.1 Exposure estimates

Some of the results are given in Figs. 1-4.

In Fig. 1 it is clearly apparent that the copper and lead load of the airborne dust decreases between the expected source - the Hettstedt smelter grounds with existing waste deposits - and the kindergarten of interest about 300 m away from the former smelter and situated in the main wind direction SSW relative to it One of the children's playgrounds - a meadow in front of the kindergarten building and in the direction of the waste deposits - is in fact loaded very highly, whereas the playground meadow behind the building is less loaded but still to an unacceptable level. Fortunately, the indoor load is minimal and is comparable to the outdoor and indoor exposure of the kindergarten in Wippra.

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Fig. 1: Lead and copper amounts in sedimentary dust

Fig. 2: Lead and copper load of milk teeth

Of special interest was the question of whether the different copper and

lead burden is also reflected in the milk teeth of the children This is true mainly for lead (Fig. 2), so that the next question to be answered was whether also the effect of this lead is detectable (see effect assessments).

The dust is also loaded with organic compounds, e.g., with pentachloro- phenol (PCP). Not only did we find such compounds in the house dust but

also their corresponding metabolites in the children's urine as a reflection of body burden.

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A comparison between outdoor/indoor load and in vivo burden was also studied for some of the 27 airborne VOCs detected. After the VOCs had been detected indoors and outdoors using personal passive monitors, we searched for their specific metabolites in the children's urine. By way of an example, we compared the mean indoor concentrations of benzene in

Hettstedt Wippra and Leipzig with the mean concentrations of its specific metabolite S-phenylmercapturic acid (SPMA). No significant differences between the towns were observed (Fig. 3).

9,00 -t 8,00- 7,00- 6,00-

5,00- 4,00 3,00- benzene 2,00-

mea n concentratio 1,00 [pg/n f / pg/ g creatinine ] 0,00- SPMA

Hettstedt Wippra Leipzig

Fig. 3: Indoor benzene concentration and SPMA excretion

Totalling the concentrations of the 27 detected VOCs at each measuring point and calculating the mean values of the towns under investigation including the city Leipzig led to the surprising result that the mean load is nearly constant over time and among the various towns (Fig. 4).

2.2 Effect assessments

Enhanced delta-aminolaevulinic acid (ALA) in the urine is an effect marker of in vivo lead burden. Fig. 5 shows the mean values for both groups. The Hettstedt group has higher levels, reflecting the effect of the higher pollution seen in Figs. 1 and 2. A trend to lower effects over the study time is apparent in both towns

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400 E31! 01!

Hettstedt Wippra Leipzig

Fig. 4: Mean VOC load of children s bedrooms in Hettstedt, Wippra and Leipzig

In addition to ALA we also estimated the probable effect of pollutants on each child's liver detoxification capacity by measuring the urinary excretion kinetics of the stable isotope labelled diagnostic agent [^N]methacetin. The results are summarised in Fig. 6. Slightly better detoxification capacity among the Wippra children relative to the Hettstedt children was assessed.

Owing to contradictory statements in the literature concerning negative lead effects on intellectual and mental capacity, we tried to answer this question especially for our group of children from Hettstedt in comparison to the Wippra group. Six physiological test kits were used to characterise various developmental performances. No considerable deviation was seen from the international norm values. Merely a slight retardation was observed in Hettstedt, but this can be compensated later on.

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May 96 Jan 97 Jun97 Jan 98

Fig. 5: Distribution of delta-aminolaevulinic acid concentration in the urine [mg/g creatinine]

^N ELIMINATION HALF LIFE [M.N]

DEC 95

Fig. 6: Relative mean detoxification capacities of Hettstedt and Wippra children during their pre-school period. Normal range: < 350 min.

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It is important to emphasise in this context that many social and socio- ecological factors influence the psychological (and also some physical) development to a great extent. Specific evaluations to be published elsewhere will consider such confounders carefully.

3 Conclusion

It was shown that a considerable number of different measurements and tests - including their multiple performance over time on the same (homogeneous and complete) population - is an attractive tool to enable the environmentally related development of even very small study groups to be assessed. This methodology permits the comparison of many parameters and values intraindividually and interindividually. The different methods augment each other.

As a mean environmental-epidemiological conclusion from the results of this study, it can be stated that the mean health status of the Hettstedt children is not alarming and does not differ from normal ranges. On the other hand, however, the lead burden in Hettstedt is still too high.

Although - apparently due to some recent conservation measures - the lead burden seems to have decreased recently, these measures do not assure further decrease. Quite the opposite: protection against airborne lead there is very limited. More sustainable protective measures must therefore be carried out there in the near future.

4 References

[1 ] Herbarth, O , Rehwagen, ML, & Ronco, A.E., The influence of

localized emittants on the concentration of volatile organic compounds in the ambient air measured close to ground level. Environ. Toxicol. Water Qual. 12, pp. 31-37, 1997

[2] Franck, U., Herbarth, O , Stark, H-J & Treide, A., Milk teeth as indicators of the lead burden of children from the industrial area of

Leipzig, Forum Stadte-Hygiene 45, pp. 189-193, 1995

[3] Krumbiegel, P., Stolz, L, Herbarth, O, Braun, W, Boehm, G,

Kausch, S & Wirsing, A., Is the [^N]methacetin liver function test suited to estimate environmental effects on the maturity of neonates? Central Europ. J. Public Health 2, pp. 49-51, 1994