The potential of spatial information in human biomonitoring by example of two German environmental epidemiology studies

This study aimed at statistically investigating the association between the internal exposure of children and young adults to uranium (U) and epidemiologically relevant external determinants of exposure. The investigation was performed with data from two studies within the framework of the German health-related environmental monitoring program: The German Environmental Survey for Children (GerES IV) conducted by the Federal Environment Agency (Umweltbundesamt) with data on 1,780 children 3–14 years of age and their home environment and the German Environmental Specimen Bank (ESB, section: human specimens) with data on 2,253 students 20–29 years of age. Both studies provided data on the U levels in human urine for all probands. GerES IV furthermore provided an extensive environmental and demographic database on, e.g., U levels in drinking water. The data from GerES IV and ESB were linked by GIS to spatially relevant exposure information, including background values of U in stream sediments and in upper and lower soils, U levels in mosses and particulate matter in the lower atmosphere, precipitation and elevation as well as forest density. Bivariate correlation analysis and two decision tree models showed moderate but significant associations between U in human urine and U levels in drinking water, stream sediments and upper and lower soils. Future investigations considering additional epidemiologically relevant data sets may differentiate the results. Furthermore, the sample design of future environmental epidemiology studies should take the spatial evaluation of the data into greater account.     

Klima wandel und Malaria

Goal and Scope

The coastal zones of Lower Saxony (Germany) are former malaria regions. Malaria had finally become extinct in the early 1950s, and subsequently related scientific investigations declined. But from that time until nowadays, the vector in the form of Anopheles mosquitoes has still been present in Lower Saxony. Thus, the question arises, whether a new autochthon transmission could take place due to the monthly mean temperatures of the recent years. Answering this question was one goal of the investigation at hand. Another one was to examine the spatial and temporal structure of potential transmissions in respect to the predicted increase of the air temperatures according to the IPCC scenarios.

Methods

Current information about anophelines and their characteristics within Germany, such as details on historical incidences, breeding preferences, longevity or distribution of the respective species, were collected by literature research. Further, measurement and incidence data had to be collected and processed: temperature values were provided by the Deutscher Wetterdienst (DWD), and recent findings of Anopheles were supplied by the former Niedersächsisches Landesamt für Ökologie (NLÖ) as a data bank. Then temperature maps were calculated for the three periods (1947–1960, 1961–1990, 1985–2004) by means of Kriging. To model areas at risk, the transmission potential for a new vivax malaria spread in respect to temperature was computed using the Basic Reproduction Rate (R₀) formula. It provides the average number of secondary infections produced when a single infected individual is introduced into a potential host population in which each member is susceptible.

Results

The computations corroborate a climate warming between the 30-years interval from 1961 to 1990 and the period from 1985 to 2004. According to the rise of the air temperature as predicted by the IPCC scenarios, the spatial pattern of potential malaria outbreak was calculated for 2020, 2060 an 2100. To this end, for each of these years a best-case-scenario with the lowest reasonable temperature increases (+0.3°C, +0.9°C, +1.4°C) and a worst-case-scenario implying the highest plausible temperature rise (+0.9°C, +3.3°C, +5.8°C) were assumed. While in 2020 the maximum duration of the transmission risk is estimated to last four months, in 2100 the vivax transmission will be likely from May until October.

Discussion

Correlated with the higher monthly mean temperature values, the risk of a vivax transmission is increasing as temperature is the determining variable of the mathematical model. Therefore Lower Saxony is at risk of a new outbreak of vivax malaria assuming no other risk factors are of relevance.

Conclusions

The study could demonstrate that most parts of the country lie within a transmission zone with a duration of two months. The areas containing the highest risk with a transmission length of three months are located around Nordhorn and Hameln, and within the rectangle of Celle, Hannover, Helmstedt and Wolfsburg. These areas match with recent Anopheles larvae finding by the NLÖ, thus, only the pathogen is lacking for a successful transmission. And as Germany is not an endemic malaria zone, the pathogen can enter the country most likely by infected people or imported mosquitoes that transport it in their guts.

Recommendations and Perspectives

The results should be understood as a request for more comprehensive investigations in that field. This would be an essential basis for a successful risk monitoring and precautionary management. Although the chances of a new endemic malaria disease in Germany seem to be considerably low today, it would be better to be prepared than to be suddenly faced with the unexpected.     

Raumgliederung für die Ökologische Umweltbeobachtung des Bundes und der Länder

Ecoregionalizations are important for the evaluation of monitoring networks. In this article a method is decribed concerning how to define Germany’s ecoregions by using ecological data on soil, vegetation, climate and elevation through the aid of classification and regression trees. The resulting ecoregions can be linked to metadata (parameters, methods, quality control and assurance measures) from thousands of Germany’s environmental monitoring sites. Together with GIS procedures, multivariate statistics and geostatistics, ecoregions are useful for integrating data of environmental measurements according to ecological and spatial criteria.     

Emissionen und Minderungspotential von HFKW, FKW und SF6 in Deutschland

The greenhouse gases subject to emission reduction commitments under the UN Climate Convention include the fluorinated compounds sulphur hexafluoride (SF₆), perfluorocarbons (PFCs) and hydrofluorocarbons (HFCs). The present study projects the emissions of these gases in Germany over the 1995–2010 period, with and without additional emission abatement efforts In the business-as-usual scenario, total emissions of the three fluorinated gases rise over the 1995–2010 period from 11,1 to 27.4 million tonnes CO₂ equivalent. This rise is attributable to 72% to HFCs, used above all for refrigeration and stationary air-conditioning, for mobile air-conditioning, for blowing extruded polystyrene (XPS) foam and for one-component polyurethane (PU) foam. Soundproof glazing is the largest SF₆ emission sector. Most PFC emissions come from semiconductor manufacturing and aluminium smelting. The reduction scenario does not achieve a stabilisation of fluorinated gas emissions either. The rate of growth is only slowed, with 11.1 million tonnes CO₂ equivalent in 1995 growing to 14.9 million in 2010. The measures proposed to attenuate emissions growth are: mandatory equipment maintenance in refrigeration and stationary air-conditioning, refrigerant substitution of HFCs by CO₂ in mobile air-conditioning, partial HFC substitution by CO₂ in XPS foam blowing, 95% HFC substitution by flammable hydrocarbons in one-component PU foam. Complete SF₆ phase-out is considered to be feasible in soundproof glazing. The PFC emissions of the semiconductor industry can be cut by 85% by new chamber cleaning technologies.     

Ausblick

Beitragsserien 2008

Ausblick     

Spatially valid data of atmospheric deposition of heavy metals and nitrogen derived by moss surveys for pollution risk assessments of ecosystems

For analysing element input into ecosystems and associated risks due to atmospheric deposition, element concentrations in moss provide complementary and time-integrated data at high spatial resolution every 5 years since 1990. The paper reviews (1) minimum sample sizes needed for reliable, statistical estimation of mean values at four different spatial scales (European and national level as well as landscape-specific level covering Europe and single countries); (2) trends of heavy metal (HM) and nitrogen (N) concentrations in moss in Europe (1990–2010); (3) correlations between concentrations of HM in moss and soil specimens collected across Norway (1990–2010); and (4) canopy drip-induced site-specific variation of N concentration in moss sampled in seven European countries (1990–2013). While the minimum sample sizes on the European and national level were achieved without exception, for some ecological land classes and elements, the coverage with sampling sites should be improved. The decline in emission and subsequent atmospheric deposition of HM across Europe has resulted in decreasing HM concentrations in moss between 1990 and 2010. In contrast, hardly any changes were observed for N in moss between 2005, when N was included into the survey for the first time, and 2010. In Norway, both, the moss and the soil survey data sets, were correlated, indicating a decrease of HM concentrations in moss and soil. At the site level, the average N deposition inside of forests was almost three times higher than the average N deposition outside of forests.     

Monitoring nitrogen accumulation in mosses in central European forests

In order to assess whether nitrogen (N) loads in mosses reflect different land uses, 143 sites in North Rhine-Westphalia, the Weser-Ems Region and the Euro Region Nissa were sampled between 2000 and 2005. The data were analysed statistically with available surface information on land use and forest conditions. N bioaccumulation in mosses in the Weser-Ems Region with high densities of agricultural land use and livestock exceeded the concentrations in the more industrialised Euro Region Nissa. In all three study areas agricultural and livestock spatial densities were found to be positively correlated with N bioaccumulation in mosses. In North Rhine-Westphalia, the N concentrations in mosses was also moderately correlated with N concentrations in leaves and needles of forest trees. The moss method proved useful to assess the spatial patterns of N bioaccumulation due to land use.