Assessment of the bioaccessibility of PAHs and other hazardous compounds present in recycled tire rubber employed in synthetic football fields

Recycled tire crumb rubber (RTCR) surfaces contain harmful and carcinogenic substances, which can be ingested by the users of these facilities, mainly athletes and children. In this work, the potential in-vitro oral bioaccessibility of eighteen polycyclic aromatic hydrocarbons (PAHs) from RTCR employed as infill in synthetic football fields was studied in human synthetic body fluids (saliva, gastric, duodenal and bile), prepared according the Unified Bioaccessibility Method. Solid-phase extraction (SPE) using commercial sorbents and a new green material based on cork (cork industry by-product) were used to isolate the bioaccessible PAHs before gas chromatography-tandem mass spectrometry analysis. The method was optimized and validated attending the analytical figures of merit. The feasibility of cork biosorbent for the extraction of the compounds was demonstrated, as well as the suitability of the UBM method to perform the digestion with good precision. The application to real samples collected from football fields demonstrated the presence of 17 of the 18 target PAHs in the biofluids. Most volatile PAHs such as NAP, ACY, ACE, FLU, PHN and ANC, achieved the highest bioaccessibility percentage levels. The carcinogenic B[a]P was detected in 75 % of the samples at concentrations up to 2.5 ng g^-1 (bioaccessible fraction). Children exposure assessment was carried out to identify potential risk. Other hazardous and environmentally problematic compounds such as N-(1,3-Dimethylbutyl)-N'-phenyl-p-phenylenediamine-quinone (6PPD-quinone), recently related with the dead of coho salmon, and hexamethoxymethylmelamine (HMMM), among others, were also detected. This is the first study in which the bioaccesibility from real crumb rubber samples of 15 out of the 16 PAHs considered as priority pollutants by the United States Environmental Protection Agency (EPA) and the presence of 6PPD-quinone and HMMM in the bioaccessible fractions is reported.

Miniaturized active air sampling method for the analysis of tire rubber pollutants from indoor and outdoor places

An effective, quick, and sustainable air analysis method was developed to analyze 41 volatiles and semivolatile organic compounds present in tire rubber and crumb rubber materials. The proposed method, based on active sampling using a sorbent material followed by an ultrasound assisted extraction, was developed with the aim of obtaining a fast and simple procedure to determine polycyclic aromatic hydrocarbons, plasticizers, antioxidants, and vulcanization agents in air. A small amount of sorbent (25 mg) was used, and the analytes were recovered in only 1 mL of solvent. An experimental design was applied to study the influence of main factors such as type of sorbent and type of solvent, extraction technique (ultrasound-assisted extraction and vortex extraction), extraction time, as well as the factor interactions. Under optimal conditions, no breakthrough occurs in the studied interval (up to 4 m³ ). Linearity was demonstrated in a wide concentration range. Accuracy of the total sampling-extraction analysis was evaluated obtaining satisfactory recoveries as well as good precision. The method was successfully applied to different outdoor and indoor air environments, including a recycled rubber synthetic turf football pitch.

Correlation of serum interleukin-6 (IL-6) levels with immunohistochemical p65/nuclear factor-κB (NF-κB) expression and prediction of the clinical outcome of hormone-independent prostate cancer patients (HIPC) treated with docetaxel (D)

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Background: We have recently reported that NF-κB/IL-6 was linked to D response in human prostate cancer cells. In this study we investigated the clinical significance of IL-6 serum levels in HIPC pts treated with D and the correlation between serum IL-6 levels and p65/NF-κB tissue expression. Methods: Pts with HIPC treated with D were prospectively tested for IL-6 levels by ELISA before chemotherapy. In patients with available specimens of hormone-independent tumor p65/NF-κB was determined by immunohistochemistry. PSA response to D, time to progression and survival were analyzed. Results: Sixty pts were included. Median follow-up time was 29.3 (5.3–55.47) months. Median time to D progression was 4.2 (0,6–15.1) months and median survival was 10.1 (1.6- 47.1) months. Median baseline IL-6 were 16 pg/ml (range 0–156). Pts that responded to D had median IL-6 of 15.1±3.9 pg/ml and patients that did not respond had median IL-6 of 34.7±6.5 (p=0.009). IL-6 correlated with the number of bone metastasis (r=0.39, p=0.002), LDH levels (r=0.53, p<0.0001) and inversely with time to PSA progression (r=-0.65, p<0.0001) and survival (r=-0.61, p<0.0001). In the multivariate analysis IL-6 were an independent prognostic factor for time to PSA progression HR 1.026 (CI95% 1.013–1.046) and survival IL-6 levels HR 1.022 (CI 95% 1.006- 1.038, p=0.008). HIPC tissue samples from 12 pts were assessed for p65/NF-κB expression. All tissue samples showed cytoplasmatic and nuclear staining. Median percentage of nuclear p65/NF-κB stained cells was 15% (range 5–45%). P65/NF-κB nuclear staining showed correlation with serum IL-6 levels (r=0.719, p=0.009). Patients with low serum IL-6 levels (= 16 pg/ml) had a median % of nuclear p65/NF-κB staining of 5.4±2.5% and patients with high IL-6 levels had a median % of nuclear p65/NF-κB staining of 30.2±4.9% (p=0.001). Conclusions: High IL-6 serum levels were associated to a worse survival in HIPC pts treated with D. Our data suggest that the determination of serum IL-6 levels may serve as a surrogate marker of NF-κB activity in hormone-independent prostate cancer tumor and may be useful to select patients for NF-κB targeted therapy.

No significant financial relationships to disclose.

Serum matrilysin (MMP7) levels are associated with progression, in curatively resected colorectal cancer (CRC) patients

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Background: Matrilysin (MMP7) has been shown to be over-expressed in CRC, specially in liver metastases. Additionally MMP7 over-expression in primary tumor, predict metastatic potential in early-stage disease (Gut 12:1751;2005). As the activated pro-domain, could be detected in serum by ELISA method, we search if it could also identify a subgroup of non-metastatic CRC patients with a higher risk of relapse. Methods: Serum MMP7 (S-MMP7) was measured by commercially available ELISA, in 92 healthy controls and 175 consecutive patients before undergoing laparoscopy-assisted or open curative resection for CRC, between July 2003 to December 2004. Clinic- pathologic variables were tested for their effect on disease-free survival (DFS) in univariate and multivariate Cox regression analysis. Results: S-MMP7 levels were significantly higher in CRC patients than in controls (p=0.02). Mean age in CRC patients was 71 years (range 31–90). Median nodal retrieval was 14 (range 0–47). The median S-MMP7 (4.9 ng/ml) was chosen for cut-off value. After a median follow- up of 26 months, the rate of DFS was 72%. Univariate analysis identified high S-MMP7 levels, CEA concentration, age, extent of primary tumor and lymph-node metastases as variables associated with DFS. Multivariate analysis identified lymph-node metastases (OR.1,88, p=0.046) and S-MMP7 (OR.1,103, p=0.039) as independent prognostics factors. Conclusions: With a short follow-up, S-MMP7 levels predict recurrence in curatively resected CRC. As a subset of these patients could be managed with secondary liver resection, S-MMP7 determination would be particularly warranted for more intensive surveillance strategies.

No significant financial relationships to disclose.

EU experimental study on wild boar trichinellosis

From January 1994 onwards the Council Directive 92/45 EEC concerning the examination of wild game meat for trichinellosis is valid. Laboratory methods required are identical to those used for the examination of pork. In an international experiment the suitability of these methods to control wild boar meat was tested. Required meat parts of experimentally with T. spiralis infected wild boars were shipped to seven laboratories in Europe under code. It was concluded that trichinoscopy and pool sample digestion methods meant for pork examination could equally well be used for control of wild boar meat. The so called Trichomatic method required a few adaptations. Moreover it was demonstrated that extra washing procedures were required to prevent cross contamination between samples with Trichomatic equipment.

Some observations on the redia, cercaria and metacercaria of Opisthodiscus nigrivasis (v. Mehlij, 1929) Odening, 1959 (Trematoda: Paramphistomidae)

The redia, cercaria and metacercaria of Opisthodiscus nigrivasis from Ancylastrum fluviatilis are described. Observations were made on the behaviour of the cercaria and experimental infections with metacercariae have been carried out in laboratory-raised frogs of the species Rana ridibunda. Some features of the morphology of these juvenile stages and aspects of the behaviour of the cercaria are compared with those of others related species.

The best known biological cycles in the Diplodiscinae are those of Diplodiscus subclavatus (Pallas, 1970) Diesing, 1836, and Megalodiscus temperatus (Stafford, 1905) Hanvood, 1932. The first was described by Looss (1892), who showed that the molluscs Planorbis nitidus, Pl. vortex, Pl. rotundatus, Pl. spirorbis and Pl. contortus acted as intermediate hosts. More recently Milka (1970) found young forms of D. subclavatus in Pl. planorbis and gave a brief description of the redia and cercaria of this species.