The effect of large anthropogenic particulate emissions on atmospheric aerosols, deposition and bioindicators in the eastern Gulf of Finland region.

The effect of the emissions from large oil shale fuelled power plants and a cement factory in Estonia on the elemental concentration of atmospheric aerosols, deposition, elemental composition of mosses and ecological effects on mosses, lichens and pine trees in the eastern Gulf of Finland region has been studied. In addition to chemical analysis, fly ash, moss and aerosol samples were analysed by a scanning electron microscope with an energy dispersive X-ray spectrometer (SEM/EDS). The massive particulate calcium emissions, approximately 60 kton/year (1992), is clearly observed in the aerosols, deposition and mosses. The calcium deposition is largest next to the Russian border downwind from the power plants and in south-eastern part of Finland. This deposition has decreased due to the application of dust removal systems at the particulate emission sources. At the Virolahti EMEP station approximately 140 km north from the emission sources, elevated elemental atmospheric aerosol concentrations are observed for Al, Ca, Fe, K and Si and during episodes many trace elements, such as As, Br, Mo, Ni, Pb and V. The acidification of the soil is negligible because of the high content of basic cations in the deposition. Visible symptoms on pine trees are negligible. However, in moss samples close to the power plants, up to 25% of the leaf surface was covered by particles. Many epiphytic lichen species do not tolerate basic stemflow and on the other hand most species are also very sensitive for the SO2 content in air. Consequently a large lichen desert is found in an area of 2500 km2 in the vicinity of the power plants with only one out of the investigated 12 species growing.

Occurrence of beta-hexachlorocyclohexane in breast cancer patients.

The residues of polycyclic aromatic hydrocarbon (PAH) and neutral organochlorine compounds in breast fat of 44 breast cancer patients and 33 women free of cancer were determined. No statistically significant differences appeared between the two comparison groups with regard to occurrence of PAH compounds. Of the neutral organochlorine compounds, residues of beta-hexachlorocyclohexane (HCH) were found more frequently in breast cancer patients. After adjusting for age and parity by stepwise logistic regression, beta-HCH remained a significant risk factor of breast cancer. Using a cutoff point for the residue level of beta-HCH in breast adipose tissue of more than 0.1 mg/kg fat, the odds ratio was 10.51 (95% CI, 2.00-55.26).

Relationships between the prevalence of multiple sclerosis and some physical and chemical properties of soil.

The prevalence of multiple sclerosis (MS) and some physical and chemical properties of soil in two counties of Finland have been compared. In the county where the MS prevalence rate was significantly higher, the pH of the soil was lower, the organic carbon content higher, the concentration of soluble iron, zinc, chromium and aluminium higher and those of soluble potassium, calcium, magnesium, strontium and total selenium lower than in the county with the lower MS-prevalence rate. According to the literature, areas of a high MS prevalence correspond rather closely to the global distribution of mires, particularly to raised bogs in the northern hemisphere.

Polycyclic aromatic hydrocarbons in Finnish sauna air.

The concentrations of polycyclic aromatic hydrocarbons (PAH) in the air of three different types of wood-heated saunas were studied. The highest concentrations were found in the smoke sauna (total PAH 170-1550 micrograms/m3, benzo[a]pyrene 4.6-20 micrograms/m3) the second highest in the preheated sauna (total PAH 50-90 micrograms/m3, benzo[a]pyrene 3.4-4.5 micrograms/m3) and the lowest concentrations in the sauna heated by continuous burning of wood (total PAH 25 micrograms/m3, benzo[a]pyrene below 0.1 micrograms/m3). The results clearly indicate that regular bathing in the smoke sauna and in the pre-heated sauna increases the intake of PAH compounds (e.g. benzo[a]pyrene and benzo[a]anthracene).