Real-time PCR detection of toxigenic Fusarium in airborne and settled grain dust and associations with trichothecene mycotoxins

Inhalation of immunomodulating mycotoxins produced by Fusarium spp. that are commonly found in grain dust may imply health risks for grain farmers. Airborne Fusarium and mycotoxin exposure levels are mainly unknown due to difficulties in identifying Fusarium and mycotoxins in personal aerosol samples. We used a novel real-time PCR method to quantify the fungal trichodiene synthase gene (tri5) and DNA specific to F. langsethiae and F. avenaceum in airborne and settled grain dust, determined the personal inhalant exposure level to toxigenic Fusarium during various activities, and evaluated whether quantitative measurements of Fusarium-DNA could predict trichothecene levels in grain dust. Airborne Fusarium-DNA was detected in personal samples even from short tasks (10-60 min). The median Fusarium-DNA level was significantly higher in settled than in airborne grain dust (p < 0.001), and only the F. langsethiae-DNA levels correlated significantly in settled and airborne dust (r(s) = 0.20, p = 0.003). Both F. langsethiae-DNA and tri5-DNA were associated with HT-2 and T-2 toxins (r(s) = 0.24-0.71, p < 0.05 to p < 00.01) in settled dust, and could thus be suitable as indicators for HT-2 and T-2. The median personal inhalant exposure to specific toxigenic Fusarium spp. was less than 1 genome m(-3), but the exposure ranged from 0-10(5) genomes m(-3). This study is the first to apply real-time PCR on personal samples of inhalable grain dust for the quantification of tri5 and species-specific Fusarium-DNA, which may have potential for risk assessments of inhaled trichothecenes.     

Dawn chorusing in guereza colobus monkeys

Dawn chorusing by guereza black-and-white colobus monkeys is one of the most impressive spectacles of African rainforests. This vocal behaviour is highly contagious, travelling from one neighbouring group to the next, until a wide forest area is covered by calling monkeys. Chorusing usually occurs up to 2 h before dawn, sometimes more than once, unless the preceding night was cold and wet. We conducted a series of playback experiments, which showed that guerezas’ chorusing was difficult to elicit experimentally, suggesting that callers took several variables into account before responding to other monkeys’ predawn calls. Acoustic analyses showed that morning calls were individually distinct, but we found no evidence that callers took individual identity into account in their decision to participate in chorusing. The only way to reliably elicit chorusing in our study area was to broadcast recordings of morning choruses for longer than 30 s and at a time when a chorus simultaneously emerged in a distant part of the forest.     

Elevated temperature elicits greater effects than decreased pH on the development, feeding and metabolism of northern shrimp (Pandalus borealis) larvae

Climate models predict that the average temperature in the North Sea could increase 3–5 °C and surface-waters pH could decrease 0.3–0.5 pH units by the end of this century. Consequently, we investigated the combined effect of decreased pH (control pH 8.1; decreased pH 7.6) and temperature (control 6.7 °C; elevated 9.5 °C) on the hatching timing and success, and the zoeal development, survival, feeding, respiration and growth (up to stage IV zoea) of the northern shrimp, Pandalus borealis. At elevated temperature, embryos hatched 3 days earlier, but experienced 2–4 % reduced survival. Larvae developed 9 days faster until stage IV zoea under elevated temperature and exhibited an increase in metabolic rates (ca 20 %) and an increase in feeding rates (ca 15–20 %). Decreased pH increased the development time, but only at the low temperature. We conclude that warming will likely exert a greater effect on shrimp larval development than ocean acidification manifesting itself as accelerated developmental rates with greater maintenance costs and decreased recruitment in terms of number and size.     

Impact of photocatalytic remediation of pollutants on urban air quality

In the recent years, photocatalytic self-cleaning and “depolluting” materials have been suggested as a remediation technology mainly for NO _x and aromatic VOCs in urban areas. A number of products incorporating the aforementioned technology have been made commercially available with the aim to improve urban air quality. These commercial products are based on the photocatalytic properties of a thin layer of TiO₂ at the surface of the material (such as glass, pavement, etc.) or embedded in paints or concrete. The use of TiO₂ photocatalysts as an emerging air pollution control technology has been reported in many locations worldwide. However, up to now, the effectiveness measured in situ and the expected positive impact on air quality of this relatively new technology has only been demonstrated in a limited manner. Assessing and demonstrating the effectiveness of these depolluting techniques in real scale applications aims to create a real added value, in terms of policy making (i.e., implementing air quality strategies) and economics (by providing a demonstration of the actual performance of a new technique).

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Arctic terrestrial biodiversity status and trends: A synopsis of science supporting the CBMP State of Arctic Terrestrial Biodiversity Report

Ambio - This review provides a synopsis of the main findings of individual papers in the special issue Terrestrial Biodiversity in a Rapidly Changing Arctic. The special issue was developed to...     

How do Europeans want to live in 2040? Citizen visions and their consequences for European land use

The aspirations, motivations and choices of individual European citizens are a major driver of the future of global, European and local land use. However, until now no land use study has explicitly attempted to find out how the general public wants to live in the future. This paper forms a first attempt to survey European citizens to understand their desired future lives in relation to consequences for European land use. We used a crowdsourcing experiment to elicit visions from young Europeans about their lives in 2040. Participants completed a graphic novel around carefully selected questions, allowing them to create a story of their imagined future lives in pictures. The methodology worked well, and the sample seemed reasonably representative albeit skewed towards an educated population. In total, 1131 responses from 29 countries were received. Results show a strong desire for change, and for more sustainable lifestyles. There is desire for local and ecologically friendly food production, to eat less meat, to have access to green infrastructure and the ability to cycle to work. However, international travel remains popular, and the desire for extensive food production and owning detached houses with gardens will likely result in complex land use trade-offs. Future work could focus more specifically on quantifying these trade-offs and inform respondents about the consequences of their lifestyle choices. This was a first attempt to use crowdsourcing to understand citizen visions for their lives in the future, and our lessons learned will help future studies improve representativeness and increase responses.

     

Cyanotoxin management and human health risk mitigation in recreational waters

The occurrence and severity of harmful cyanobacterial or blue-green algal blooms (HABs) have increased in recent decades, posing a serious threat of illness to humans. In some countries, water contaminated with cyanotoxins that is used for drinking or haemodialysis has posed a particularly serious risk. However, it is now recognized that recreational exposure to natural toxins by skin contact, accidental swallowing of water or inhalation can also cause a wide range of acute or chronic illnesses. In this review, we focus on the importance of cyanotoxin management in recreational waters. The symptoms related with HAB poisonings, the recommended safety concentrations limit for cyanobacteria and cyanotoxins in such waters, as well as early health hazard indicators of their presence and their monitoring are all discussed. We also present in this review an overview of the methods developed in recent decades for eliminating cyanobacteria and the toxic compounds that they produce.     

Transformation kinetics of 6-methoxybenzoxazolin-2-one in soil

Wheat (Triticum aestivum L.) and other cereals produce allelochemicals as natural defense compounds against weeds, fungi, insects and soil-borne diseases. The main benzoxazinoid allelochemical of wheat is 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA), bound as beta-glucoside and released upon plant injury. When leached from wheat to soil, DIMBOA is microbially transformed to 6-methoxy-benzoxazolin-2-one (MBOA). Exploiting benzoxazinoids and their degradation products as substitutes for synthetic pesticides depends on knowledge of transformation pathways and kinetics. In an MBOA degradation experiment at a concentration of 2400 nmol g(-1) soil, the previously identified transformation products 2-amino-7-methoxy-phenoxazin-3-one (AMPO) and 2-acetylamino-7-methoxy-phenoxazin-3-one (AAMPO) were quantified. Three different kinetic models were applied to MBOA transformation kinetics; single first-order (SFO), first-order multi-compartment, and double first-order in parallel. SFO proved to be adequate and was subsequently applied to the transformations of MBOA, AMPO and AAMPO. Degradation endpoints, expressed as degradation time (DT), were calculated for MBOA, AMPO and AAMPO to test whether the maximum values for synthetic pesticides set by the European Commission and the Danish Environmental Protection Agency were exceeded. DT(50) values for MBOA and AMPO were 5.4 d and 321.5 d, respectively, and DT(90) values were 18.1 d and 1068 d, respectively. The DT(50) value for AMPO exceeded the maximum value. The persistence, concentrations and toxicity of metabolites such as AMPO should be considered when breeding cereal crops with increased levels of benzoxazinoids.