The Panel on Food Additives and Nutrient Sources added to Food (ANS) provided a scientific opinion re-evaluating the safety of potassium nitrite (E 249) and sodium nitrite (E 250) when used as food additives. The ADIs established by the SCF (1997) and by JECFA (2002) for nitrite were 0-0.06 and 0-0.07 mg/kg bw per day, respectively. The available information did not indicate in vivo genotoxic potential for sodium and potassium nitrite. Overall, an ADI for nitrite per se could be derived from the available repeated dose toxicity studies in animals, also considering the negative carcinogenicity results. The Panel concluded that an increased methaemoglobin level, observed in human and animals, was a relevant effect for the derivation of the ADI. The Panel, using a BMD approach, derived an ADI of 0.07 mg nitrite ion/kg bw per day. The exposure to nitrite resulting from its use as food additive did not exceed this ADI for the general population, except for a slight exceedance in children at the highest percentile. The Panel assessed the endogenous formation of nitrosamines from nitrites based on the theoretical calculation of the NDMA produced upon ingestion of nitrites at the ADI and estimated a MoE > 10,000. The Panel estimated the MoE to exogenous nitrosamines in meat products to be < 10,000 in all age groups at high level exposure. Based on the results of a systematic review, it was not possible to clearly discern nitrosamines produced from the nitrite added at the authorised levels, from those found in the food matrix without addition of external nitrite. In epidemiological studies there was some evidence to link (i) dietary nitrite and gastric cancers and (ii) the combination of nitrite plus nitrate from processed meat and colorectal cancers. There was evidence to link preformed NDMA and colorectal cancers.
The Panel on Food Additives and Nutrient Sources added to Food (ANS) provided a scientific opinion re‐evaluating the safety of sodium nitrate (E 251) and potassium nitrate (E 252) when used as food additives. The current acceptable daily intakes (ADIs) for nitrate of 3.7 mg/kg body weight (bw) per day were established by the SCF (1997) and JECFA (2002). The available data did not indicate genotoxic potential for sodium and potassium nitrate. The carcinogenicity studies in mice and rats were negative. The Panel considered the derivation of an ADI for nitrate based on the formation of methaemoglobin, following the conversion of nitrate, excreted in the saliva, to nitrite. However, there were large variations in the data on the nitrate‐to‐nitrite conversion in the saliva in humans. Therefore, the Panel considered that it was not possible to derive a single value of the ADI from the available data. The Panel noticed that even using the highest nitrate‐to‐nitrite conversion factor the methaemoglobin levels produced due to nitrite obtained from this conversion would not be clinically significant and would result to a theoretically estimated endogenous N‐nitroso compounds (ENOC) production at levels which would be of low concern. Hence, and despite the uncertainty associated with the ADI established by the SCF, the Panel concluded that currently there was insufficient evidence to withdraw this ADI. The exposure to nitrate solely from its use as a food additive was estimated to be less than 5% of the overall exposure to nitrate in food based on a refined estimated exposure scenario. This exposure did not exceed the current ADI (SCF, 1997). However, if all sources of exposure to dietary nitrate are considered (food additive, natural presence and contamination), the ADI would be exceeded for all age groups at the mean and the highest exposure.
Kidney cancer is the 13th most common malignancy worldwide with significant increase in Stage I renal cell cancer (RCC). Surgical excision by nephron sparing surgery (NSS) remains the treatment of choice for small renal masses (SRMs). One of the variants of partial nephrectomy is simple enucleation (SE) or tumor enucleation (TE). The present review comments on the indications and technical aspects of SE as well as its outcomes. SE/TE has shown both perioperative and oncologic satisfactory results, comparable to partial nephrectomy (PN). It is a valid technique for SRMs and achieves maximum renal parenchymal preservation with an insignificant impact on renal function.
Participatory ergonomics is an intervention strategy acting on physical load exposures occurring in occupational settings, scarcely known in Spain but with a number of experiences and evidences coming from other countries. There are several reasons justifying the interest of this approach. First, participatory ergonomics focuses on one of the categories of occupational exposures with the largest impact on workers' health in a majority of countries all over the world, in terms of incidence, prevalence and disability. Secondly, basic principle in participatory ergonomics is empowerment of workers for them to participate identifying risks and injuries caused by physical exposures at work as well as proposing and evaluating proper control measures for each situation. Thirdly, it allows dealing and solving a number of problems without the use of complex technical protocols. From a public health perspective, participatory ergonomics is a largely tried model of community empowerment for the control of (occupational) factors affecting health and wellbeing. In this paper we revise some basic principles of participatory ergonomics, we comment on the keys leading to success or failing of the interventions and we present some main results coming from participatory ergonomics experiences developed for a long time in countries such as Canada, United Kingdom, Netherlands or Finland.
ObjectivesThis study aimed to determine students’ satisfaction with a 2-day course on scientific writing in health sciences and to assess their perceptions of the long-term impact on their knowledge, attitudes and skills.Setting27 iterations of a 2-day course on writing and publishing scientific articles in health sciences.Participants741 students attending the 27 courses.DesignProspective longitudinal study.Primary and secondary outcome measuresImmediately after each course, students completed a first questionnaire, rating their satisfaction with different aspects of the classroom sessions on a Likert scale (0–5). Approximately 2 years after the course, students completed a follow-up questionnaire, using a Likert scale (0–4) to rate their knowledge, skills and attitudes in relation to scientific writing before and after attending the course.Results741 students (70% women) participated in the 27 iterations of the course; 568 (76.8%) completed the first questionnaire and 182 (24.6%) completed the follow-up questionnaire. The first questionnaire reflected high overall satisfaction (mean score, 4.6). In the second questionnaire, students reported that the course had improved their knowledge (mean improvement: 1.6; 95% CI 1.6 to 1.7), attitudes (mean improvement: 1.3; 95% CI 1.2 to 1.4) and skills (mean improvement: 1.4; 95% CI 1.3 to 1.4) related to writing and publishing scientific papers. Most respondents (n=145, 79.7%) had participated in drafting a scientific paper after the course; in this subgroup, all the specific writing skills assessed in the second questionnaire significantly improved.ConclusionsStudents were satisfied with the format and the contents of the course, and those who responded to the follow-up survey considered that the course had improved their knowledge, attitudes and skills in relation to scientific writing and publishing. Courses are particularly important in countries without strong traditions in scientific publication.
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