PCDD/PCDF, PCB, and Hexachlorobenzene in soil, bottom ash and products from brickmaking sites in developing countries - Results from surveys in Kenya, Mexico, and South Africa. A contribution to the Standardized Toolkit for Identification and Quantification of Dioxin and Furan Releases in support to the Stockholm Convention on Persistent Organic Pollutants

The report combines the results from soil sampling campaigns executed in Mexico, South Africa and Kenya in order to assess the impact of artisanal brick making on local environments. Moreover the study serves indirectly (through the comparison of the impact on soils), whether the emission factors for brick kilns obtained in in a separate study in Mexico can be applied to other developing countries. These emission factors will be introduced into the calculation scheme for the National Emission Inventories of unintentional POP's releases ("dioxin toolkit) which is the reporting tool under the reporting obligations laid down in the Stockholm Convention of POPs. Results revealed, that the soils in Mexico are higher contaminated then in South Africa and Kenya, most probably due to the practice of co-incineration of waste (oils), whereas in Africa coal or virgin biomass are used as fuels. In so far the emission factors obtained in Mexico apparently represent the upper range of emission factors for brick making.JRC.D.2-Water and Marine Resource

Microbial degradation of Di-ester plasticizers in the presence of surfactants

The degradation of common di-ester plasticizers, including di-2-ethylhexyl phthalate, di-2-ethylhexyl adipate and di-(propylene glycol) dibenzoate, by several strains of soil bacteria has been previously shown to lead to an accumulation of metabolites that are more toxic than the parent compounds. This research has shown that the pattern of degradation of these plasticizers can be significantly different in the presence of biosurfactants or synthetic surfactants. In particular, the additions of surfactin, sophorolipid or Pluronic L122 to cultures of Bacillus subtilis each resulted in increases in the quantities of the first metabolites in the plasticizer degradation pathway. One of these was 2-ethylhexanol, which had been previously shown to be the most toxic intermediate released during plasticizer degradation. The other was mono-2-ethylhexyl adipate, the mono-ester released from the hydrolysis of di-2-ethylhexyl adipate. This compound was isolated in this work and found to have a toxicity comparable to that of 2-ethylhexanol.The cause of the significant accumulation of the first and most toxic plasticizer metabolites in the presence of surfactants was investigated. Results were obtained that suggested that the action of the surfactants was to sequester these initial metabolites. The effect of this would be to reduce the observed rates of subsequent degradation of these two intermediates to less toxic compounds

METHODS FOR THE DETERMINATION OF HEXABROMOCYCLODODECANE IN FOOD

Methods of sample preparation with a particular emphasis on extraction and purification techniques are described. Gas and liquid chromatography techniques applied for the determination of hexabromocyclododecane are presented. Issues relating to the determination of this compound in food samples are discussed

Level of hexabromocyclododecane isomers in the tissue of selected commonly consumed fish in Central European countries

This paper is focused on the determination of three hexabromocyclododecane isomers, α, β, and γ, in the tissue of the most commonly consumed marine and farmed fish in Central Europe. The analytical procedure contains multiple steps: extraction, dialysis using semipermeable membranes, and a clean-up step using a silica gel column. Hexabromocyclododecane (HBCD) isomers were determined by sensitive isotope dilution liquid chromatography-tandem mass spectrometry (LC-MS/MS) method which is characterized by a low limit of detection (1 pg g−1 fresh weight). The recovery values obtained for individual isomers were in the range of 89–124%. The γ-HBCD isomer was detected in all samples. This isomer also had the largest percentage in comparison with the other isomers, except in salmon, in which the α-HBCD isomer was more abundant. The highest level of total HBCD was measured in mackerel (650 ± 195 pg g−1 fresh weight). Cluster analysis allowed the differentiation of groups of objects and the display of objects based on the degree of integration within the same group. Spearman’s rank correlation indicated no statistically significant difference between the levels of HBCD and the fat content in the fish samples.Web of Science26458557

Effect of a two-week treatment with low dose of ortho-substituted polychlorinated biphenyls (PCB104 and PCB153) on VEGF-receptor system expression in the choroid plexus in adult ewes

Ortho-substituted polychlorinated biphenyl (PCB) congeners, which constitute a large part of PCB residues found in the environment and in animal tissues, are known to exert potent vascular effects and can activate endothelial cells in the periphery and in the brain. The choroid plexus (CP) is responsible for cerebrospinal fluid (CSF) production and its epithelial cell layer is responsible for structure and functions of the blood-CSF barrier. The aims of this study were: 1) to investigate if environmentally relevant doses of PCB153 and similar doses of PCB104 caused changes in the expression of vascular endothelial growth factor (VEGF) - receptor system, which maintains CP function, and 2) to determine the level of both congeners in blood plasma after their oral administration. Studies of both congeners were performed on ovariectomized ewes treated per os with low doses (0.1 mg/kg, three times a week for two weeks) of PCB153 (n=4) or PCB104 (n=4) and vehicle (control, n=4). The effects of PCB153 and PCB104 treatment on mRNA expression of two isoforms of VEGF (VEGF(120) and VEGF(164)) and their receptors Flt-1 and KDR were determined using real-time PCR. Plasma concentration of PCBs was measured using high resolution chromatography/tandem mass spectrometry (HRGC/MS-MS). We observed that neither PCB153 nor PCB104 significantly altered the mRNA of the VEGF-receptor system in the CP. In PCB treated animals plasma concentration of PCB153 (1.425 +/- 0.16 ng/g of dry mass, DM) was about 150 times higher than PCB104 (0.009 +/- 0.007 ng/g DM). In control animals the PCB153 level was 0.14 +/- 0.031 ng/g DM, while the PCB104 level was below detection level. This indicates that increase in plasma PCB153 concentration to levels similar to those reported in humans and of PCB104 concentration to levels 100 times higher than those found in human plasma did not affect the VEGF-receptor system in the CP in adult ewes. The significantly lower increase of PCB104 than PCB153 concentration in blood after oral administration suggests different absorption of both congeners from the digestive tract

The influence of rifaximin on diverticulitis rate and quality of life in patients with diverticulosis

Diverticulosis, its associated symptoms and complications are one of the most common pathologies of the gastrointestinal tract in more economically developed countries. Presence of diverticuli and their clinical consequences can be divided into four categories: 1) diverticulosis, i.e. an asymptomatic presence of diverticuli that are usually found by accident 2) symptomatic uncomplicated diverticulosis 3) diverticulitis (acute uncomplicated diverticulitis) 4) complications of diverticulitis (conditions requiring hospital stay). The aim of this study was to retrospectively analyze the efficacy of rifaximin in preventing diverticulitis in patients visiting proctology clinics. The diagnostic criterium for diverticulosis was confirmation by colonoscopy, barium enema or CT colography (virtual colonoscopy) as well as history of at least one documented episode of diverticulosis. History of diverticulosis was evaluated based on medical records, clinical symptoms, elevated level of CRP (>5.0) and/or diagnostic imaging (ultrasound, CT). After setting strict exclusion criteria, 248 patients were qualified for the study out of 686, and they were later divided into two groups: control group (group I – 145 patients) and studied group (group II – 103 patients receiving rifaximin prophylaxis). Diverticulitis rate was comparable in both groups over a period of 6 months before study (p = 0.1306) and 6 months of treatment (p=0.3044). Between the 6th and 12th month of treatment, a significantly lower rate of diverticulitis was noted in the group receiving rifaximin compared to control group (p<0.0001). Patients receiving rifaximin reported higher quality of life (which was assessed using the VAS scale) compared to control group after 12 months. The results confirmed the efficacy of riaximin in prevention of diverticulitis, even in the scheme of repeated courses every 3 months. Not only did application of rifaximin lower the rate of diverticulitis and its complications in patients after an episode of diverticulitis, but also it improved the patients’ quality of life. It seems that diverticulitis prophylaxis based on rifaximin can be economically efficient, however, it requires further research

Wpływ profilaktycznego stosowania rifaksyminy na występowanie zapaleń uchyłków i jakość życia chorych z chorobą uchyłkową

Uchyłki jelita grubego i związane z nimi dolegliwości kliniczne oraz powikłania to jedna z najczęstszych patologii przewodu pokarmowego w krajach wysokorozwiniętych. Obecność uchyłków jelita grubego oraz związane z nimi konsekwencje kliniczne podzielić można na cztery podstawowe postacie: 1) uchyłkowatość, czyli obecność uchyłków jelita grubego nie dających objawów klinicznych i wykrywanych zazwyczaj przypadkowo, 2) objawowa niepowikłana choroba uchyłkowa, 3) zapalenie uchyłków (ostre niepowikłane zapalenie uchyłków), 4)powikłania zapalenia uchyłków (obejmujące stany wymagające hospitalizacji). Celem niniejszej pracy była retrospektywna analiza efektywności stosowania rifaksyminy w profilaktyce występowania zapalenia uchyłków u  pacjentów leczonych w  poradniach proktologicznych. Kryterium rozpoznania choroby uchyłkowej stanowiło potwierdzenie występowania uchyłków jelita grubego na podstawie badania kolonoskopowego, wlewu kontrastowego lub kolografii KT (wirtualnej kolonoskopii) oraz co najmniej jednego przebytego (udokumentowanego) epizodu zapalenia uchyłków. Przebyte zapalenie uchyłków stwierdzano na podstawie dokumentacji medycznej, potwierdzającej obecność objawów klinicznych, oraz podwyższonej wartości CRP (>5,0), lub/i wyników badań obrazowych (USG, KT). Spośród 686 pacjentów leczonych w poradni, po przyjęciu restrykcyjnych kryteriów wykluczenia, do badania zakwalifikowano 248 chorych, których podzielono na dwie grupy: kontrolną (grupa I –145 chorych) i badaną (grupa II – 103 pacjentów stosujących profilaktycznie rifaksyminę). Liczba zapaleń uchyłków u pacjentów w obu grupach była zbliżona w okresie 6 miesięcy przed rozpoczęciem badania (p=0,1306) i w pierwszych 6 miesiącach terapii (p=0,3044). Między 6. a 12. miesiącem terapii, odnotowano istotnie mniejszą liczbę zapaleń uchyłków u pacjentów stosujących profilaktycznie rifaksyminę, w porównaniu do grupy kontrolnej (p<0,0001). Pacjenci, którym podawano rifaksyminę, mieli istotnie wyższą jakość życia (mierzoną wg. skali VAS) niż w ci w grupie kontrolnej po 12 miesiącach zażywania rifaksyminy. Wyniki badania potwierdziły efektywność stosowania rifaksyminy w profilaktyce zapalenia uchyłków, nawet w schemacie kuracji powtarzanej co 3 miesiące. Stosowanie rifaksyminy u pacjentów z epizodem zapalenia uchyłków nie tylko zmniejszało częstość występowania zapaleń i ich powikłań, ale również poprawiało jakość życia tych chorych. Wydaje się również, że profilaktyka zapaleń uchyłków oparta o rifaksyminę może być efektywna ekonomicznie, wymaga to jednak dalszej analizy i badań