Styrofoam debris as a potential carrier of mercury within ecosystems

The present paper falls within the trend of research into interactions between various pollutants emitted anthropogenically into the environment and focuses on mercury and styrofoam debris. The study covers part of the Southern Baltic’s drainage area. Apart from styrofoam and beach sand, the research involved mosses, which are bioindicators of atmospheric metal pollution. The research has shown that mercury present in the environment becomes associated with styrofoam debris. The median for mercury concentrations in virgin styrofoam samples (0.23 ng g^?1 dry weight (d.w.)) and in beach sand samples (0.69 ng g^?1 d.w.) was an order of magnitude lower than in the styrofoam debris (5.20 ng g^?1 d.w.). The highest mercury content observed in styrofoam debris (3,863 ng g^?1 d.w.) exceeded the standards for bottom sediment and soil. The binding of mercury to styrofoam debris takes place in water, and presumably also through contact with the ground. A significant role in this process was played by biotic factors, such as the presence of biofilm and abiotic ones, such as solar radiation and the transformations of mercury forms related to it. As a result, mercury content in styrofoam debris underwent seasonal changes, peaking in summertime. Furthermore, the regional changes of mercury content in the studied debris seem to reflect the pollution levels of the environment.     

Generality of relationships between leaf pigment contents and spectral vegetation indices in Mallorca (Spain)

Vegetation indices are calculated from reflectance data of discrete spectral bands. The reflectance signal in the visible spectral range is dominated by the optical properties of photosynthetic pigments in plant leaves. Numerous spectral indices have been proposed for the estimation of leaf pigment contents, but the efficacy of different indices for prediction of pigment content and composition for species-rich communities is unknown. Assessing the ability of different vegetation indices to predict leaf pigment content we identify the most suitable spectral indices from an experimental dataset consisting of field-grown high light exposed leaves of 33 angiosperm species collected in two sites in Mallorca (Spain) with contrasting leaf anatomy and pigment composition. Leaf-level reflectance spectra were recorded over the wavelength range of 400 – 900 nm and contents of chlorophyll a, chlorophyll b, total carotenoids, and anthocyanins were measured in 33 species from different plant functional types, covering a wide range of leaf structures and pigment content, five-fold to more than 10-fold for different traits. The best spectral region for estimation of leaf total chlorophyll content with least interference from carotenoids and anthocyanins was the beginning of near-infrared plateau well beyond 700 nm. Leaves of parallel-veined monocots and pinnate-veined dicots had different relationships between vegetation indices and pigments. We suggest that the nature and role of “far-red” chlorophylls which absorb light at longer wavelengths than 700 nm constitute a promising target for future remote sensing studies.

     

The transfer of active ingredients of insecticides and fungicides from an orchard to beehives

This investigation was undertaken to determine whether active ingredients (AIs) of currently recommended plant protection products (PPPs) could be transferred to beehives from apple and pear trees. A field trial was carried out with apple trees of Ligol and Idared variety, and pear trees of Conference variety. For pest and diseases control of fungal origin, recommended PPPs were applied. Samples of flowers from the above-mentioned varieties of fruit trees, of bees, brood and honey from beehives located in their direct neighborhood were collected regularly and analyzed for the presence of lambda-cyhalothrin (an insecticide) and cyprodinil, captan, fluopyram, kresoxim-methyl, penthiopyrad and trifloxystrobin (fungicides). In samples of flowers of Ligol variety, fluopyram residues (on average 0.621 µg single flower^?1) were at the highest levels, whereas in samples of pear flowers of Conference variety, and in flowers of Idared variety, captan residues (on average, respectively, 0.705 and 165.7 µg single flower^?1). In samples of bees and honey, residues of five AIs were detected, and in brood six AIs, whereby in each case captan residues prevailed, respectively, up to 585.2, 51.52 and 126.5 µg kg^?1 bees and honey. In the honey, significantly larger residues of captan were found out than maximum residue level (MRL) for this AI – 103.04% MRL. In the case of any AI, the daily intake did not exceed 0.002% acceptable daily intake (ADI).     

Occupational exposure to mould and microbial metabolites during onion sorting—insights into an overlooked workplace

Manual sorting of onions is known to be associated with a bioaerosol exposure. The study aimed to gain an initial indication as to what extent manual sorting of onions is also associated with mycotoxin exposure. Twelve representative samples of outer onion skins from different onion origins were sampled and analyzed with a multimycotoxin method comprising 40 mycotoxins using a single extraction step followed by liquid chromatography with electrospray ionization and triple quadrupole mass spectrometry. Six of the 12 samples were positive for mycotoxins. In those samples, deoxynivalenol, fumonisin B₁, and B₂ were observed in quantitatively detectable amounts of 3940 ng/g for fumonisin B₁ and in the range of 126–587 ng/g for deoxynivalenol and 55–554 ng/g for fumonisin B₂. Although the results point to a lower risk due to mycotoxins, the risk should not be completely neglected and has to be considered in the risk assessment.     

Dissipation kinetics of alpha-cypermethrin and lambda-cyhalothrin residues in aboveground part of white mustard (Sinapis alba L.)

Dissipation of simultaneously applied insecticides alpha-cypermethrin and lambda-cyhalothrin was studied in a minor crop, aboveground part of white mustard (Sinapis alba L.). A validated gas chromatographic method (GC-ECD/NPD) was used to determine insecticide residues. Analytical performances were very satisfactory, with expanded uncertainties not higher than 14% (coverage factor k = 2, confidence level 95%). Dissipation of alpha-cypermethrin and lambda-cyhalothrin in white mustard followed first-order kinetics (R² between 0.953 and 0.995), with half-lives of 3.1–4.6 and 2.9–3.7 days respectively. Based on the results of this two-year study and the relevant residue regulation, alpha-cypermethrin and lambda-cyhalothrin treatments can be considered safe for crop protection, feeding animals and the environment.     

Life cycle assessment of hydrotreated vegetable oil from rape,oil palm and Jatropha

A life cycle assessment of hydrotreated vegetable oil (HVO) biofuel was performed. The study was commissioned by Volvo Technology Corporation and Volvo Penta Corporation as part of an effort to gain a better understanding of the environmental impact of potential future biobased liquid fuels for cars and trucks. The life cycle includes production of vegetable oil from rape, oil palm or Jatropha, transport of the oil to the production site, production of the HVO from the oil, and combustion of the HVO. The functional unit of the study is 1 kWh energy out from the engine of a heavy-duty truck and the environmental impact categories that are considered are global warming potential (GWP), acidification potential (AP), eutrophication potential (EP) and embedded fossil production energy. System expansion was used to take into account byproducts from activities in the systems; this choice was made partly to make this study comparable to results reported by other studies. The results show that HVO produced from palm oil combined with energy production from biogas produced from the palm oil mill effluent has the lowest environmental impact of the feedstocks investigated in this report. HVO has a significantly lower life cycle GWP than conventional diesel oil for all feedstocks investigated, and a GWP that is comparable to results for e.g. rape methyl ester reported in the literature. The results show that emissions from soil caused by microbial activities and leakage are the largest contributors to most environmental impact categories, which is supported also by other studies. Nitrous oxide emissions from soil account for more than half of the GWP of HVO. Nitrogen oxides and ammonia emissions from soil cause almost all of the life cycle EP of HVO and contribute significantly to the AP as well. The embedded fossil production energy was shown to be similar to results for e.g. rape methyl ester from other studies. A sensitivity analysis shows that variations in crop yield and in nitrous oxide emissions from microbial activities in soil can cause significant changes to the results.     

Assessment of boscalid and pyraclostrobin disappearance and behavior following application of effective microorganisms on apples

ABSTRACT

The aim of this study is to assess the disappearance of boscalid (IUPAC name: 2-chloro-N-[2-(4-chlorophenyl)phenyl]pyridine-3-carboxamide) and pyraclostrobin (IUPAC name: methyl N-[2-[[1-(4-chlorophenyl)pyrazol-3-yl]oxymethyl]phenyl]-N-methoxycarbamate) residues in apple fruit, and to verify whether an organic fertilizer enriched with strains of antagonistic microorganisms can reduce pesticide residue levels. Field trials were conducted in a commercial orchard on apples of the Gloster variety, during 21 days after the treatment with Bellis 38 WG and the subsequent application of Zumba Plant formulation containing Bacillus spp., Trichoderma spp. and Glomus spp. In control samples, the decrease rate of boscalid and pyraclostrobin residue levels followed an exponential function, described by formulae R_t = 0.2824e^?0.071t and R_t = 0.1176e^?0.060t, with the coefficient of determination of r² = 0.8692 and r² = 0.9268, respectively. These levels dropped to half (t_1/2) of their initial values after 9.8 and 11.5 days, respectively. The treatment with Zumba Plant resulted in a reduction in boscalid and pyraclostrobin residue levels by 52% and 41%, respectively. The results of this study are of importance for horticulture sciences and for producers of apples using plant protection products (PPPs).     

White rot fungi can be a promising tool for removal of bisphenol A,bisphenol S,and nonylphenol from wastewater

Environmental Science and Pollution Research - Endocrine-disrupting chemicals (EDC) are a wide group of chemicals that interfere with the endocrine system. Their similarity to natural steroid...     

Biomonitoring of arsenic through mangrove oyster (Crassostrea corteziensis Hertlein, 1951) from coastal lagoons (SE Gulf of California): occurrence of arsenobetaine and other arseno-compounds

In this study, we examined the bioavailability of arsenic through the mangrove oyster Crassostrea corteziensis sampled from seven coastal lagoons in SE Gulf of California during the rainy and dry seasons. As concentrations in soft tissue of oysters C. corteziensis fluctuated between 5.2 and 11.6 μg/g on dry weight; organisms from the control site presented the lowest As concentrations in the two sampling seasons. As speciation was evaluated in selected samples and indicated that arsenobetaine was the major arseno-compound accounting for 53.5–74.7 % of total As. Lower percentage contributions were obtained for nonextractable As (9.7–25.5 %) and other molecules such as arsenocholine and methyl-arsonate (<5 %). Inorganic As was detectable in only two samples, at concentrations lower than 0.1 μg/g. These As data are the first generated in NW Mexico and indicate that C. corteziensis is safe for human consumption in terms of arseno-compounds. It is evident that As bioavailability in these lagoons is low.