Pojavnost aflatoksina M1 u uzorcima jogurta pronađenima na tržištu u Kosovu tijekom proljeća 2023.

Aflatoxin M1 (AFM1), a toxic byproduct of aflatoxin B1 (AFB1) produced by Aspergillus fungi, is a carcinogenic mycotoxin that can contaminate various agricultural commodities. It can be transferred from AFB1-contaminated feed to milk and dairy products, including yogurt, posing a potential health risk to consumers. In spring 2023, a total of 74 yogurt samples were collected from the largest food suppliers in Kosovo for analysis, including samples produced in Kosovo and seven other countries: Albania, North Macedonia, Bosnia and Herzegovina, Slovenia, Greece, Italy, and Germany. A rapid and sensitive analytical method, Enzyme-linked immunosorbent assay (ELISA), was used for the analysis. The results of the study highlight discernible differences in the maximum tolerable levels of AFM1 between the countries. More specifically, yogurt samples from Slovenia and Germany had lower levels than those from other countries. Additionally, the median levels of AFM1 in samples from Slovenia and Germany were significantly lower. The mean concentrations of AFM1 in yogurt samples from Kosovo and other countries were 0.071 μg/kg and 0.080 μg/kg, respectively. Out of all samples, 66 (89%) exceeded the maximum tolerable limit of 0.05 μg/kg. Among the exporting countries, Albania had the highest median AFM1 level of 0.085 μg/kg and the highest maximum level of 0.195 μg/kg. Slovenia had the lowest median AFM1 level, while Germany had the lowest maximum AFM1 level. All samples from Albania, Greece, and Bosnia and Herzegovina exceeded the maximum tolerable limit. High prevalence was also observed in samples from Kosovo, North Macedonia, and Slovenia. Considering the average daily consumption of about 250 grams of yogurt, and the total median value of Aflatoxin M1 concentration (0.071 μg/kg), the estimated daily intake was calculated to be 0.017 μg. These findings highlight the importance of monitoring and enforcing regulatory limits to ensure yogurt safety and to protect public health. Efforts should be focused on mitigating AFM1 contamination and implementing measures to minimise its presence in dairy products, especially in regions where levels exceed the established limits.Aflatoksin M1 (AFM1), toksični nusproizvod aflatoksina B1 (AFB1) kojeg proizvode gljivice Aspergillus kancerogeni je mikotoksin koji može kontaminirati različite poljoprivredne proizvode. Može se prenijeti iz hrane za životinje kontaminirane s AFB1 na mlijeko i mliječne proizvode, uključujući jogurt, predstavljajući potencijalni rizik po zdravlje potrošača. U proljeće 2023. godine prikupljeno je ukupno 74 uzoraka jogurta od najvećih dobavljača hrane na Kosovu za analizu, uključujući uzorke proizvedene na Kosovu i u sedam drugih zemalja: Albaniji, Sjevernoj Makedoniji, Bosni i Hercegovini, Sloveniji, Grčkoj, Italiji i Njemačkoj. Za analizu je rabljena brza i osjetljiva analitička metoda, Enzimski povezani imunosorbentni test (ELISA). Rezultati studije ukazuju da nalazi ove studije naglašavaju zamjetne razlike u maksimalno dopuštenim razinama AFM1 između različitih zemalja. Točnije, u uzorcima jogurta iz Slovenije i Njemačke zamijećene su niže razine od onih iz drugih zemalja. Uz to, srednje razine AFM1 u uzorcima iz Slovenije i Njemačke bile su značajno niže. Srednje koncentracije AFM1 u uzorcima jogurta s Kosova i iz drugih zemalja bile su 0,071 μg/kg, odnosno 0,080 μg/kg. Od svih uzoraka, 66 (89 %) prekoračilo je maksimalno dopušteno ograničenje od 0,05 μg/kg. Od zemalja izvoznica, Albanija je imala najveću srednju razinu AFM1 od 0,085 μg/kg i najveću maksimalnu razinu od 0,195 μg/kg. Slovenija je imala najnižu srednju razinu AFM1, a Njemačka najnižu maksimalnu razinu AFM1. Svi uzorci iz Albanije, Grčke i Bosne i Hercegovine prekoračili su maksimalnu dopuštenu razinu. Visoka prevalencija zamijećena je i u uzorcima s Kosova, iz Sjeverne Makedonije i Slovenije. Razmatrajući prosječnu dnevnu konzumaciju od jedne čašice od oko 250 g jogurta i ukupnu srednju vrijednost koncentracije aflatoksina M1 (0,071 μg/kg), izračunat je procijenjeni dnevni unos od 17,75 μg. Ovi nalazi naglašavaju važnost nadziranja i provođenja regulatornih ograničenja kako bi se osigurala sigurnost jogurta i zaštitilo javno zdravlje. Potrebno je uložiti napore za smanjenje kontaminacije AFM1 i provedbu mjera za smanjenje njegove prisutnosti u mliječnim proizvodima, posebice u regijama gdje razine prekoračuju utvrđena ograničenja

Comparison of quantitative Holocene temperature reconstructions using multiple proxies from a northern boreal lake

Four biotic proxies (plant macrofossils, pollen, chironomids and diatoms) are employed to quantitatively reconstruct variations in mean July air temperatures (T-jul) at Lake Loitsana (northern Finland) during the Holocene. The aim is to evaluate the robustness and biases in these temperature reconstructions and to compare the timing of highest T-jul in the individual reconstructions. The reconstructed T-jul values are evaluated in relation to local-scale/site-specific processes associated with the Holocene lake development at Loitsana as these factors have been shown to significantly influence the fossil assemblages found in the Lake Loitsana sediments. While pollen-based temperatures follow the classical trend of gradually increasing early-Holocene T-jul with a mid-Holocene maximum, the aquatic/wetland assemblages reconstruct higher-than-present T-jul already during the early Holocene, that is, at the peak of summer insolation. The relatively low early-Holocene July temperatures recorded by the pollen are the result of site-specific factors possibly combined with a delayed response of the terrestrial ecosystem compared with the aquatic ecosystem. Our study shows that all reconstructions are influenced at least to some extent by local factors. This finding stresses the need to evaluate quantitatively reconstructed climate values against local lake development and highlights the benefit of using multi-proxy data in Holocene climate reconstructions.Peer reviewe

Warm summers and rich biotic communities during N-Hemisphere deglaciation

Detailed studies on fossil remains of plants or animals in glacial lake sediments are rare. As a result, environmental conditions right at the moment of deglaciation of the large N-Hemisphere ice-sheets remain largely unknown. Here we study three deglacial phases of the Fennoscandian Ice Sheet as a unique, repeated element in a long sediment record preserved at Sokli in northern Finland. We summarize extensive multi-proxy data (diatoms, phytoliths, chironomids, pollen, spores, non-pollen palynomorphs, macrofossils, lithology, loss-on-ignition, C/N) obtained on glacial lake sediments dated to the early Holocene (ca. 10 kyr BP), early MIS 3 (ca. 50 kyr BP) and early MIS 5a (ca. 80 kyr BP). In contrast to the common view of an unproductive ice-marginal environment, our study reconstructs rich ecosystems both in the glacial lake and along the shores with forest on recently deglaciated land. Higher than present-day summer temperatures are reconstructed based on a large variety of aquatic taxa. Rich biota developed due to the insolation-induced postglacial warming and high nutrient levels, the latter resulting from erosion of fresh bedrock and sediment, leaching of surface soils, decay of plant material under shallow water conditions, and sudden decreases in lake volume. Aquatic communities responded quickly to deglaciation and warm summers and reflect boreal conditions, in contrast to the terrestrial ecosystem which responded with some delay probably due to time required for slow soil formation processes. Birch forest is reconstructed upon deglaciation of the large LGM ice-sheet and shrub tundra following the probably faster melting smaller MIS 4 and MIS 5b ice-sheets. Our study shows that glacial lake sediments can provide valuable palaeo-environmental data, that aquatic biota and terrestrial vegetation rapidly accommodated to new environmental conditions during deglaciation, and that glacial lake ecosystems, and the carbon stored in their sediments, should be included in earth system modeling.Peer reviewe

Palaeoenvironmental changes in the northern boreal zone of Finland: local versus regional drivers

Multiple proxies derived from the Lake Loitsana sediment sequence (NE Finland) are employed to determine the timing of deglaciation, characterise an early Holocene proglacial lake stage and reconstruct Holocene lake development. Local-scale processes causing shifts in biological assemblages are identified and the most likely Holocene mean July air temperature (Tjul) development is assessed. The study area was deglaciated shortly prior to 10 700 cal. a BP. The sediment record reflects four local events; the presence of a glacial lake, glacial lake drainage and formation of Lake Loitsana, changes in fluvial input due to progressive wetland expansion, and gradual lake infilling. The results suggest that local events have driven changes in biological assemblages through various processes, and that biotic proxies reflect changes in environmental parameters in a highly individual manner. Furthermore, biological assemblages can themselves act as important drivers, influencing the composition of other assemblages. It is suggested that future studies should consider macrophyte abundance and food-web interactions as equally important factors when assessing changes in biological assemblages. Quantitative Tjul reconstructions based on biotic proxies display contrasting trends. While Tjul reconstructions based on pollen found in the Loitsana sequence display relatively low early Holocene values, plant macrofossil and chironomid data reflect warm summer conditions also during the early Holocene, i.e. at the peak of summer insolation. The early Holocene Tjul recorded by terrestrial pollen are affected by local factors possibly combined with a delayed response of the terrestrial ecosystem compared to the aquatic one. This study emphasises the importance of using multiple proxies in palaeoenvironmental studies and shows that local factors have a potential to drive changes in biological assemblages that can affect transfer-function based temperature reconstructions.At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Epub ahead of print. Paper 2: Accepted. Paper 3: Manuscript.</p

Publisher Correction: A global database of Holocene paleotemperature records

In an earlier version of this Data Descriptor the figure images 4, 5 and 6 were swapped. Both the HTML and PDF versions have been updated to reflect this change

Publisher Correction: A global database of Holocene paleotemperature records

In an earlier version of this Data Descriptor the figure images 4, 5 and 6 were swapped. Both the HTML and PDF versions have been updated to reflect this change

A global database of Holocene paleotemperature records

A comprehensive database of paleoclimate records is needed to place recent warming into the longer-term context of natural climate variability. We present a global compilation of quality-controlled, published, temperature-sensitive proxy records extending back 12,000 years through the Holocene. Data were compiled from 679 sites where time series cover at least 4000 years, are resolved at sub-millennial scale (median spacing of 400 years or finer) and have at least one age control point every 3000 years, with cut-off values slackened in data-sparse regions. The data derive from lake sediment (51%), marine sediment (31%), peat (11%), glacier ice (3%), and other natural archives. The database contains 1319 records, including 157 from the Southern Hemisphere. The multi-proxy database comprises paleotemperature time series based on ecological assemblages, as well as biophysical and geochemical indicators that reflect mean annual or seasonal temperatures, as encoded in the database. This database can be used to reconstruct the spatiotemporal evolution of Holocene temperature at global to regional scales, and is publicly available in Linked Paleo Data (LiPD) format