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This study aims to assess the airborne bioburden of rural and urban Portuguese Primary Health Care Centers (PHCC) using active and passive sampling methods and identify the potential differences in airborne microbiota between both environments. The highest total aerobic mesophilic bacterial load in indoor air were found in the Vaccination Room (448 CFU.m−3) in the Rural PHCC and in the Waiting Room (420 CFU.m−3) for Urban PHCC. The total coliforms contamination level in indoor air was detected only in the Cleaning Supplies Room (4 CFU.m−3) in the Urban PHCC. The most frequent bacteria genera identified was Micrococcus (21% Rural PHCC; 31% Urban PHCC). The surface samples showed a highest total aerobic mesophilic bacterial contamination in the Treatment Room (86 × 103 CFU.m−2) from the Rural PHCC and in the Front Office (200 × 103 CFU.m−2) from the Urban PHCC. The electrostatic dust cloth (EDC) samples showed a highest bacterial load in the Urban PHCC. Total aerobic mesophilic bacterial load in settled dust and in the Heating, Ventilating and Air Conditioning (HVAC) filter samples in the Urban PHCC (8 CFU.g−1 and 6 × 103 CFU.m−2) presented higher values compared with the Rural PHCC (1 CFU.g−1 and 2.5 × 103 CFU.m−2). Urban PHCC presented higher bacterial airborne contamination compared with the Rural PHCC for the ma-jority of sampling sites, and when compared with the indoor air quality (IAQ) Portuguese legislation it was the Rural PHCC in two sampling places who did not comply with the established criteria. publishersversion published

ICFC 2017 - International Conference on Food Contaminants (Book of Abstracts), Ochratoxin A (OTA) is one of the main mycotoxins found in food. Gamma radiation is used for preserving foods since it inactivates pathogens. The effect of irradiation on mycotoxins has been studied but results are contradictory. The different matrices and conditions used by several authors may have influenced reported results. The aim of this work was to study the effects of gamma radiation in OTA in order to evaluate its applicability in foods. OTA was irradiated in its dry form, in aqueous and in methanolic solutions to evaluate the water role in OTA irradiation. Then, OTA contaminated food matrices, such as wheat flour, grape juice and wine, were irradiated.In aqueous solutions, high degradation of OTA (≥90%) was obtained with gamma radiation doses as low as 2.5kGy. However, in dried samples, OTA was found extremely resistant to radiation doses of up to 10kGy. In this case, water was a determinant factor for the effectiveness of irradiation process. In the assays with food matrices, radiation doses greater than 10kGy were needed to achieve higher reductions of OTA, being eliminated just 24%. It was also observed that OTA elimination was higher in wheat flour with higher moisture contents but the elimination of OTA in grape juice and wine were not higher than those observed in wheat flour. It is concluded that OTA is very sensitive to irradiation in water solutions but resistant in its dry form and in food matrices. Due to the low elimination percentage observed, it can be considered that gamma radiation is not a suitable technology for the elimination of OTA from foods., Thalita Calado and Luís Abrunhosa received support by grants SFRH/BD/79364/2011 and UMINHO/BPD/51/2015 from FCT, respectively. CEB gratefully acknowledge FCT support through projects UID/BIO/04469/2013, NORTE-01-0145-FEDER-000004, and RECI/BBB-EBI/0179/2012. The C2TN/IST authors gratefully acknowledge their FCT support through projects RECI/AAG-TEC/0400/2012 and UID/Multi/04349/2013., info:eu-repo/semantics/publishedVersion

[Excerpt] Mycotoxins are secondary toxic metabolites of filamentous fungi. Aflatoxins (AFs) are produced to Aspergillus species such as A. flavus and A. parasiticus. These fungi are ubiquitous in nature and usually found on agricultural commodities. Therefore, AFs are encountered in many important foodstuff, including wheat, rice, maize, peanuts, sorghum, pearl millet, spices, oilseeds, tree nuts and milk. Due to the high toxicity of AFs, many methods have been studied to reduce or eliminate these mycotoxins from food and feed. Gamma irradiation is one technology that has been investigated with promising results. The aims of this study were (I) to study the effect of gamma radiation on aflatoxin B1, aflatoxin B2, aflatoxin G1 and aflatoxin G2 (II) to evaluate the effect of the presence of water on AFs degradation during the irradiation process; and (IV) to evaluate the cytotoxicity of radiolytic products formed. (...)