Landscape history improves detection of marginal habitats on semi-natural grasslands.

Semi-natural grassland habitats have markedly declined from their historical coverage, thus causing substantial losses for agricultural biodiversity and establishing a consequent need to spot the remaining habitat patches. These patches are generally remnants of once larger habitat areas, formed by uninterrupted and low-intensity management for centuries, but then later being isolated and fragmented into smaller pieces. In the light of this development, past landscape phases have a crucial role for the present existence of semi-natural grasslands. The importance of historical factors has been indicated in many studies but evaluation of their added value, or actual site-specific effects compared to observations of only the present landscape characteristics, is not generally provided. As data related to the past is often difficult to obtain, tedious to process and challenging to interpret, assessment of its advantages and related effects - or consequences of potential exclusion - would be needed. In this study, we used maximum entropy approach to model the distribution of Fumewort (Corydalis solida) which in the study area is a good indicator of valuable semi-natural habitats. We constructed three different models - one based on only the contemporary environment with expected indicators of habitat stability, one solely on the historical landscape phases and long-term dynamics, and one combining variables from the past and the present. Predictions of the three models were validated and compared with each other, followed by an analysis indicating the similarity of model results with known Fumewort occurrences. Our results indicate that present landscapes may provide workable surrogates to delineate larger core habitats, but utilization of historical data markedly improves the detection of small outlying patches. These conclusions emphasize the importance of previous landscape phases particularly in detecting marginal semi-natural grassland habitats, existing in contemporarily suboptimal conditions and being prone to disappear if no further actions are taken.

Dietary intakes of polychlorinated dibenzo-p-dioxins, dibenzofurans and polychlorinated biphenyls in Finland.

Samples of cow milk, pork, beef eggs, rainbow trout, flours and vegetables were analysed for 17 polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F) and 36 polychlorinated biphenyls (PCB). Daily dietary intake of PCDD/Fs as toxic equivalent (I-TEq) and PCBs (PCB-TEq) was assessed using food consumption data from a 24-h dietary recall study for 2862 Finnish adults. The calculated intake of PCDD/F was 46 pg I-TEq day(-1). The current level was about half of the earlier estimation of intake in Finland made in 1992. The assessed PCB intake was 53 pg PCB-TEq day(-1). Thus, the total intake of PCDD/Fs and PCBs was 100 pg TEqday(-1) (1.3pg TEqkg(-1) b.w. day(-1)), which is within the range of tolerable daily intake (TDI) proposed by the WHO (1-4pg TEqkg(-1) b.w. day(-1)).

Determination of anthocyanidins in berries and red wine by high-performance liquid chromatography.

A high-performance liquid chromatographic (HPLC) method for the determination of anthocyanidins from berries and red wine is described. Delphinidin, cyanidin, petunidin, pelargonidin, peonidin, and malvidin contents of bilberry (Vaccinium myrtillus), black currant (Ribes nigrum), strawberry (Fragaria ananassa cv. Jonsok), and a Cabernet sauvignon (Vitis vinifera) red wine were determined. The aglycon forms of the anthocyanins present in the samples were revealed by acid hydrolysis. A reversed phase analytical column was employed to separate the anthocyanidins before identification by diode array detection. The suitability of the method was tested by determining the recovery (95-102% as aglycons and 69-104% from glycosides) for each anthocyanidin. Method repeatability was tested by charting the total aglycon content of two samples over a period of 14 analyses and determining the coefficients of variation (1.41% for bilberry and 2.56% for in-house reference material). The method developed proved thus to be effective for reliable determination of anthocyanidins from freeze-dried berry samples and red wine. The total anthocyanidin content of the tested samples was as follows: in-house reference material, 447 +/- 8 mg/100 g; strawberry, 23.8 +/- 0.4 mg/100 g; black currant, 135 +/- 3 mg/100 g; bilberry, 360 +/- 3 mg/100 g; and Cabernet sauvignon red wine, 26.1 +/- 0.1 mg/100 mL.

Contents of vitamins, mineral elements, and some phenolic compounds in cultivated mushrooms.

The aim of the study was to determine the contents of mineral elements (Ca, K, Mg, Na, P, Cu, Fe, Mn, Cd, Pb, and Se), vitamins (B(1), B(2), B(12), C, D, folates, and niacin), and certain phenolic compounds (flavonoids, lignans, and phenolic acids) in the cultivated mushrooms Agaricus bisporus/white, Agaricus bisporus/brown, Lentinus edodes, and Pleurotus ostreatus. Selenium, toxic heavy metals (Cd, Pb), and other mineral elements were analyzed by ETAAS, ICP-MS, and ICP methods, respectively; vitamins were detected by microbiological methods (folates, niacin, and vitamin B(12)) or HPLC methods (other vitamins), and phenolic compounds were analyzed by HPLC (flavonoids) or GC--MS methods (lignans and phenolic acids). Cultivated mushrooms were found to be good sources of vitamin B(2), niacin, and folates, with contents varying in the ranges 1.8--5.1, 31--65, and 0.30--0.64 mg/100 g dry weight (dw), respectively. Compared with vegetables, mushrooms proved to be a good source of many mineral elements, e.g., the contents of K, P, Zn, and Cu varied in the ranges 26.7--47.3 g/kg, 8.7--13.9 g/kg, 47--92 mg/kg, and 5.2--35 mg/kg dw, respectively. A. bisporus/brown contained large amounts of Se (3.2 mg/kg dw) and the levels of Cd were quite high in L. edodes (1.2 mg/kg dw). No flavonoids or lignans were found in the mushrooms analyzed. In addition, the phenolic acid contents were very low.

Comparison of in-line connected diode array and electrochemical detectors in the high-performance liquid chromatographic analysis of coenzymes Q(9) and Q(10) in food materials.

In-line connected electrochemical (EC) and diode array (DAD) detectors were compared in the reversed-phase high-performance liquid chromatographic (RP-HPLC) analysis of coenzymes Q(9) and Q(10) in some food materials (beef steak, beef heart, Baltic herring fillet, and rye flour). Coenzymes Q(9) and Q(10) were extracted from the samples using a 5:1 n-hexane-ethanol mixture. Coefficient of variation (CV%) of quadruplicate or quintuplicate determined samples for coenzymes Q(9) and Q(10) was <10 by both EC detector and DAD. Responses of the detection systems were linear in the range evaluated, 10-200 ng/injection, and had correlation coefficients exceeding 0.999. Recoveries of added coenzymes Q(9) and Q(10) varied 73-105% for DAD and 74-103% for EC detector, respectively. Detection limits for coenzymes Q(9) and Q(10) using the DAD system were 4 and 6 ng/injection, respectively, and 0.2 and 0.3 ng/injection by EC detection. Results derived from the two detection systems were generally similar. However, although EC detector was 20-fold more sensitive, the selectivity was, in some cases, poorer than that of DAD.

Determination of flavonoids in plant material by HPLC with diode-array and electro-array detections.

A high-performance liquid chromatographic (HPLC) method with in-line connected diode-array (DAD) and electro-array (EC) detection to identify and quantify 17 flavonoids in plant-derived foods is described. Catechins were extracted from the samples using ethyl acetate, and quantification of these compounds was performed with the EC detector. Other flavonoids were quantified with DAD after acid hydrolysis. The methods developed were effective for the determination of catechins and other flavonoids in plant-derived foods. Responses of the detection systems were linear within the range evaluated, 20-200 ng/injection (DAD) and 20-100 ng/injection (EC), with correlation coefficients exceeding 0.999. Coefficient of variation was under 10.5%, and recoveries of flavonoids ranged from 70 to 124%. Purity of the flavonoid peaks was confirmed by combining the spectral and voltammetric data.

Contents of lead and cadmium in selected fish species consumed in Finland in 1993-1994.

The lead and cadmium contents of the main fish species consumed in Finland were determined by ETAAS after wet digestion with HNO3. Analytical quality was controlled with blanks, reference materials and blind replicates. Mean and median lead contents of domestic fish species were < LOD (1 microgram/kg)-9.4 micrograms/kg and < LOD-4.7 micrograms/kg. The lead contents of imported fish and imported canned or salted fish ranged from < LOD to 8, and 4 to 177 micrograms/kg. Mean and median cadmium contents of domestic fish species were < LOD (0.4 microgram/kg)-5.8 micrograms/kg and < LOD-4.4 micrograms/kg Fresh imported fish contained < LOD-11 micrograms Cd per kg and canned or salted fish 9-42 micrograms Cd per kg. Higher fish consumption would not increase lead or cadmium intake significantly in Finland. At present fish contributes about 4% of the average lead intake and 3% of cadmium intake.

Lead and cadmium contents in milk, cheese and eggs on the Finnish market.

Lead and cadmium contents were determined in nationally representative samples of low-fat milk, cheese and eggs consumed in Finland. Nationally representative samples of milk and cheese were collected from dairies. Egg samples were collected from the major distributors. Samples of imported cheese and egg products collected in surveillance studies were analysed, together with domestic samples. Lead and cadmium were determined by GFAAS after wet digestion in conc. HNO3. In lead determinations of milk and cheese platinum was employed as the matrix modifier and NH4H2PO4 was employed for the lead determinations of eggs and in all cadmium determinations. Mean lead content was 1.7 micrograms/kg in milk, 17 micrograms/kg in Finnish cheese, 17-60 micrograms/kg in imported cheese, 1 microgram/kg in eggs and 6-72 micrograms/kg in imported dry egg products. Although Finnish consumption in milk, cheese and eggs is high the dietary intake of lead and cadmium from these sources is very low compared with the tolerance limits.

The status of trace elements in staple foods from the former Federal Republic of Germany. I. Contents of 11 trace elements.

In representative samples of bread cereals and cereal products from the former Federal Republic of Germany (FRG) the status of 11 trace elements was analysed in 1989. It is demonstrated that the results are quite representative for the former FRG as compared with results published in the previous 15 years. The sampling technique for staple foods is explained. A number of certified standard reference materials were used to validate the analytical methods employed.

The status of trace elements in staple foods. II. Some effects of cereal and potato processing.

The effects of food processing on some cereal and potato products are discussed with respect to the status of 11 trace elements. The influences of milling, bread making and cooking of potatoes on the contents of trace elements are demonstrated. It is shown that these recently obtained results are quite representative for the former federal Republic of Germany (FRG) as compared with results published previously. Average intake levels of undesired elements such as cadmium and lead, as well as of essential elements such as calcium, copper, iron, magnesium, manganese, molybdenum, nickel, selenium and zinc via consumption of cereal and potato products are calculated.

Lead and cadmium in some berries and vegetables on the Finnish market in 1991-1993.

In order to determine the present contribution of vegetables and berries to the intake of lead and cadmium in Finland major vegetable groups as well as strawberries and blackcurrants were collected from wholesale distribution centres, orchards and the food industry. Pooled samples were mixed to represent wholesale distribution centres, exporting countries or geographical regions. Lead and cadmium were determined after wet digestion in concentrated HNO3 using ETAAS with Zeeman effect background correction and 0.1% palladium for lead and (NH4)H2PO4 for cadmium matrix modification. The method of standard additions was used for the quantification. The mean lead and cadmium contents found were: iceberg lettuce 1.1 and 20.9, butterhead lettuce 4.5 and 12.2, Chinese cabbage 1.4 and 11.1, cauliflower 1.6 and 7.1, cucumber 0.7 and 0.6, carrot 5.9 and 24.6, tomato 1.5 and 1.5, leek 3.8 and 12.8, cabbage 1.3 and 3.1, paprika 3.1 and 5.3, potato 5 and 6 (domestic) or 5 and 31 (imported), strawberry 6.5 and 13.7, blackcurrant 12.7 and 1.4 micrograms/kg. The contents found in this study are the lowest reported so far in Finland and equal to or lower than those found elsewhere.

Lead, cadmium and mercury contents in average Spanish market basket diets from Galicia, Valencia, Andalucía and Madrid.

This study was undertaken in order to monitor the intake of lead, cadmium and mercury in different geographical areas of Spain. The intakes of four populations were estimated from their habitual diets and compared with the Provisional Tolerable Weekly Intake (PTWI) or the Acceptable Daily Intake (ADI) to estimate the health risk of toxicity. Representative market basket diets from four areas, Galicia, Valencia, Andalucía and Madrid, were collected and their contents of cadmium, lead and mercury determined. The number of different foodstuffs used in each area (64, 67, 71 and 73) was based on the number of foods providing 95% of the total energy intake. Data on the contribution of food groups to the total daily intake of heavy metals were also obtained. The daily amounts of lead in the diets were between 37 and 521 micrograms/day, the Madrid population having the highest average intake of this metal and exceeding the PTWI, because of the vegetables and cereals consumed. The average total dietary cadmium intakes--provided mainly by fish including crustacea and molluscs--were about 25-45% of the PTWI. The intake of mercury, which is mainly provided by the fish group (66-90%), was about 9-17% of the PTWI.

Isomer specific analysis of PCBs and organochlorine pesticides in Finnish diet samples and selected individual foodstuffs.

Twenty organochlorine pesticide compounds (OCPs) and 20 polychlorinated biphenyl (PCB) congeners known to be the most abundant or toxicologically significant were determined in samples of a representative Finnish diet and in individual foodstuffs. OCPs were isolated and cleaned-up by solvent extraction and concentrated sulphuric acid treatment according to the methods given by Moilanen et al. (1986) or Veierov and Aharonson (1980). Instrumental analysis was performed by gas chromatography-mass spectrometry using selected ion monitoring. PCBs were determined by a congener-specific method. There were very low levels of most OCPs and PCB congeners in the present Finnish market basket, hospital diet, milk, cheese and egg samples. The average total PCB intake from the diets was approximately 2.3 micrograms/day per capita, which represents 3% of the highest tolerable intake proposed by the US Food and Drug Administration.

Lead and cadmium contents in Finnish breads.

A total of 647 breads from nine bakeries were pooled into 48 representative samples. After wet digestion in concentrated HNO3, the contents of lead and cadmium were determined using electrothermal atomic absorption spectrometry with Zeeman effect background correction and (NH4)H2PO4 matrix modification. The mean lead and cadmium contents found in the various types of bread were: rye bread 16 and 14, coffee bread 19 and 23, French bread 8 and 27, whole wheat bread 8 and 30, mixed bread group I 17 and 27, and mixed bread group II 14 and 28 micrograms/kg. The mean and median lead contents of all breads were 14 and 8 micrograms/kg. The samples showed a very high variation in their lead contents. In the present study, the lead content found in Finnish breads was much lower than that in the late 1970s. The mean and median cadmium contents in all of the bread samples analysed were 24 and 25 micrograms/kg. The cadmium content of rye breads was clearly lower than that of the other bread types studied. The content of cadmium in the different types of bread was at about the same level as that reported in Finnish breads in the late 1970s.

Lead and cadmium contents in pork, beef and chicken, and in pig and cow liver in Finland during 1991.

Nationally representative samples of pork, beef, chicken, and pig's and cow's liver were collected from slaughterhouses and pooled to represent the collection area of each slaughterhouse. The lead (Pb) and cadmium (Cd) contents of the freeze-dried samples were analysed after wet digestion in concentrated HNO3 using ETAAS (Varian Spectra AA 400), Zeeman background correction and (NH4)H2PO4 as the matrix modifier. A strict analytical quality control programme including reference materials and recovery tests was employed. The average Pb content of beef (tenderloin) was 10 micrograms/kg, ground beef 8 micrograms/kg, cow's liver 37 micrograms/kg, pork (regular loin) 9 micrograms/kg, pig's liver 11 micrograms/kg and chicken 6 micrograms/kg. The mean Cd contents of beef, pork and chicken were lower than the limit of detection of the method employed. The mean Cd content of cow's liver was 66 micrograms/kg (cow) and 36 micrograms/kg (heifer) and that of pig's liver 21 micrograms/kg. The contents of lead and cadmium were low in all samples studied, approximately the same level or lower than those found in earlier Finnish studies. These results are in good agreement with the earlier Finnish Market Basket Study in which very low average lead and cadmium intakes were found.

Factors affecting the selenium intake of people in Transbaikalian Russia.

The selenium concentration in foods grown and consumed and in plasma, red blood cells, and toenails of people living in the district of Chita in the transbaikalian part of Russia were studied in August 1991. Preliminary results from the area have suggested low selenium intakes and the possible occurrence of cardiomyopathy (Keshan disease) in the population. A low selenium concentration in foods grown locally was found: mean selenium concentration in wheat grains was 1, 5, and 28 micrograms/kg, respectively, in three villages studied, that of oats was between 3-6 micrograms/kg, and of cow's milk 10-27 micrograms/kg dry matter. The selenium concentration of bread was considerably higher, between 87-337 micrograms/kg dry wt, presumably because wheat imported from the US had been used for baking. Occasional samples of pork, beef, and mutton contained between 32-218 micrograms selenium/kg dry wt. Low selenium concentrations were observed in samples of soil and river water. The mean plasma selenium concentration of 52 persons was 1.02 mumol/L, including 33 children and 19 adult subjects. The selenium concentrations in red blood cells and toenails were 1.95 mumol/L and 0.61 mg/kg, respectively. No symptoms of heart disease caused by selenium deficiency were observed. It is concluded that the selenium status of people was fairly good thanks to the contribution to dietary intake of imported wheat with a high selenium content. As the selenium concentration was very low in foods grown in the area, the selenium intake of the population will be reduced to a very low level if only locally produced foods are consumed.

Lead and cadmium in some cereal products on the Finnish market 1990-91.

Lead and cadmium contents were determined in representatively collected (commercial mills, wholesalers) samples of rye flour, breakfast cereals, porridge flakes, muesli cereals and pasta products. The samples were digested by heating them overnight in concentrated HNO3. Lead and cadmium concentrations were determined by GFAAS using a platform and (NH4)H2PO4 as a matrix modifier. ARC/CL coded wheat flour and other reference materials (NBS 1567a, BCR no. 189, BCR no. 191) were employed for the analytical quality control. Lead and cadmium contents found in the above samples were generally much lower than the present tolerance limits in Finland (300 micrograms/kg and 100 micrograms/kg respectively). The mean cadmium and lead contents of rye flours studied were very low, being 9 micrograms/kg and 16 micrograms/kg respectively. The mean contents of lead and cadmium in wheat-based breakfast cereals were 22 and 42, in rye products 19 and 26, in oats 17 and 2, in maize products 11 and 18 and in rice products 31 and 10 micrograms/kg, respectively. The mean contents of lead and cadmium in muesli cereals were 34 and 27 micrograms/kg. Remarkably high cadmium contents were found in some pastas made from imported durum wheat. The mean cadmium content of all past products was 79 micrograms/kg with a range of 26-182 micrograms/kg. Lead contents were low, with a mean of 18 micrograms/kg, and a range of 8 to 66 micrograms/kg. Cereals contribute about 59% of the average total dietary cadmium intake in Finland. Nearly 60% of the total cereal consumption is wheat and 27% rye. Since rye has a lower cadmium content than wheat, rye is preferable to wheat. About 15% of lead is derived from cereals. As the total intake of heavy metals is very low in Finland, there is no need to alter cereal consumption.