1,152 research outputs found
Scientific Opinion on the re-evaluation of Quinoline Yellow (E 104) as a food additive:Question No EFSA-Q-2008-223
The Panel on Food Additives and Nutrient Sources added to Food provides a scientific opinion re-evaluating the safety of Quinoline Yellow (E 104). Quinoline Yellow has been previously evaluated by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) in 1975, 1978 and 1984, and the EU Scientific Committee for Food (SCF) in 1984. Both committees established an Acceptable Daily Intake (ADI) of 0-10 mg/kg body weight (bw). Studies not evaluated by JECFA and the SCF included a chronic toxicity and carcinogenicity study with a
reproductive toxicity phase in rats and a study on behaviour in children by McCann et al. from 2007. The latter study concluded that exposure to a mixture of colours including Quinoline Yellow resulted in increased hyperactivity in 8- to 9-years old children. The Panel concurs with the conclusion from a previous EFSA opinion on the McCann et al. study that the findings of the study cannot be used as a basis for altering the ADI. The Panel notes that Quinoline Yellow was negative in in vitro genotoxicity as well as in long term carcinogenicity studies. The Panel concludes that the currently available database on semi-chronic, reproductive, developmental and long-term toxicity of Quinoline Yellow, including a study in rats not apparently taken into
consideration by JECFA or the SCF, provides a rationale for re-definition of the ADI. Using the NOAEL of 50 mg/kg bw/day provided by the chronic toxicity and carcinogenicity study with a reproductive toxicity phase carried out in rats and applying an uncertainty factor of 100 to this NOAEL, the Panel establishes an ADI of 0.5 mg/kg bw/day. The Panel notes that at the maximum levels of use of Quinoline Yellow, refined intake estimates are generally well over the ADI of 0.5 mg/kg bw/day
Designing Equitable Antiretroviral Allocation Strategies in Resource-Constrained Countries
BACKGROUND: Recently, a global commitment has been made to expand access to antiretrovirals (ARVs) in the developing world. However, in many resource-constrained countries the number of individuals infected with HIV in need of treatment will far exceed the supply of ARVs, and only a limited number of health-care facilities (HCFs) will be available for ARV distribution. Deciding how to allocate the limited supply of ARVs among HCFs will be extremely difficult. Resource allocation decisions can be made on the basis of many epidemiological, ethical, or preferential treatment priority criteria. METHODS AND FINDINGS: Here we use operations research techniques, and we show how to determine the optimal strategy for allocating ARVs among HCFs in order to satisfy the equitable criterion that each individual infected with HIV has an equal chance of receiving ARVs. We present a novel spatial mathematical model that includes heterogeneity in treatment accessibility. We show how to use our theoretical framework, in conjunction with an equity objective function, to determine an optimal equitable allocation strategy (OEAS) for ARVs in resource-constrained regions. Our equity objective function enables us to apply the egalitarian principle of equity with respect to access to health care. We use data from the detailed ARV rollout plan designed by the government of South Africa to determine an OEAS for the province of KwaZulu–Natal. We determine the OEAS for KwaZulu–Natal, and we then compare this OEAS with two other ARV allocation strategies: (i) allocating ARVs only to Durban (the largest urban city in KwaZulu–Natal province) and (ii) allocating ARVs equally to all available HCFs. In addition, we compare the OEAS to the current allocation plan of the South African government (which is based upon allocating ARVs to 17 HCFs). We show that our OEAS significantly improves equity in treatment accessibility in comparison with these three ARV allocation strategies. We also quantify how the size of the catchment region surrounding each HCF, and the number of HCFs utilized for ARV distribution, alters the OEAS and the probability of achieving equity in treatment accessibility. We calculate that in order to achieve the greatest degree of treatment equity for individuals with HIV in KwaZulu–Natal, the ARVs should be allocated to 54 HCFs and each HCF should serve a catchment region of 40 to 60 km. CONCLUSION: Our OEAS would substantially improve equality in treatment accessibility in comparison with other allocation strategies. Furthermore, our OEAS is extremely different from the currently planned strategy. We suggest that our novel methodology be used to design optimal ARV allocation strategies for resource-constrained countries
Food additives and children's behaviour: evidence‐based policy at the margins of certainty
The possible effects of food additives (specifically artificial colours) have been debated for over 30 years. The evidence accumulated suggests that for some children with attention deficit hyperactivity disorder (ADHD) food colours exacerbate their condition. Two studies
undertaken by a research group at the University of Southampton have extended these findings to the effects on hyperactivity in children from the general population who do not show ADHD. This article reviews the response from policy-makers to these findings and concludes that the failure to impose a mandatory ban on the six food colours in the Southampton study is inadequate and that such a ban would be an appropriate application of the precautionary principle when the evidence is considered to be at the margins of certaint
Adverse Effects of Methylmercury: Environmental Health Research Implications
Background: The scientific discoveries of health risks resulting from methylmercury exposure began in 1865 describing ataxia, dysarthria, constriction of visual fields, impaired hearing, and sensory disturbance as symptoms of fatal methylmercury poisoning. Objective: Our aim was to examine how knowledge and consensus on methylmercury toxicity have developed in order to identify problems of wider concern in research. Data sources and extraction: We tracked key publications that reflected new insights into human methylmercury toxicity. From this evidence, we identified possible caveats of potential significance for environmental health research in general. Synthesis: At first, methylmercury research was impaired by inappropriate attention to narrow case definitions and uncertain chemical speciation. It also ignored the link between ecotoxicity and human toxicity. As a result, serious delays affected the recognition of methylmercury as a cause of serious human poisonings in Minamata, Japan. Developmental neurotoxicity was first reported in 1952, but despite accumulating evidence, the vulnerability of the developing nervous system was not taken into account in risk assessment internationally until approximately 50 years later. Imprecision in exposure assessment and other forms of uncertainty tended to cause an underestimation of methylmercury toxicity and repeatedly led to calls for more research rather than prevention. Conclusions: Coupled with legal and political rigidity that demanded convincing documentation before considering prevention and compensation, types of uncertainty that are common in environmental research delayed the scientific consensus and were used as an excuse for deferring corrective action. Symptoms of methylmercury toxicity, such as tunnel vision, forgetfulness, and lack of coordination, also seemed to affect environmental health research and its interpretation
The characterisation of sexual behaviour in Chinese male university students who have sex with other men: A cross-sectional study
Adverse Effects of Methylmercury: Environmental Health Research Implications
Background: The scientific discoveries of health risks resulting from methylmercury exposure began in 1865 describing ataxia, dysarthria, constriction of visual fields, impaired hearing, and sensory disturbance as symptoms of fatal methylmercury poisoning. Objective: Our aim was to examine how knowledge and consensus on methylmercury toxicity have developed in order to identify problems of wider concern in research. Data sources and extraction: We tracked key publications that reflected new insights into human methylmercury toxicity. From this evidence, we identified possible caveats of potential significance for environmental health research in general. Synthesis: At first, methylmercury research was impaired by inappropriate attention to narrow case definitions and uncertain chemical speciation. It also ignored the link between ecotoxicity and human toxicity. As a result, serious delays affected the recognition of methylmercury as a cause of serious human poisonings in Minamata, Japan. Developmental neurotoxicity was first reported in 1952, but despite accumulating evidence, the vulnerability of the developing nervous system was not taken into account in risk assessment internationally until approximately 50 years later. Imprecision in exposure assessment and other forms of uncertainty tended to cause an underestimation of methylmercury toxicity and repeatedly led to calls for more research rather than prevention. Conclusions: Coupled with legal and political rigidity that demanded convincing documentation before considering prevention and compensation, types of uncertainty that are common in environmental research delayed the scientific consensus and were used as an excuse for deferring corrective action. Symptoms of methylmercury toxicity, such as tunnel vision, forgetfulness, and lack of coordination, also seemed to affect environmental health research and its interpretation
The emergence of international food safety standards and guidelines: understanding the current landscape through a historical approach
Following the Second World War, the Food and Agriculture Organization (FAO) and the World Health Organization (WHO) teamed up to construct an International Codex Alimentarius (or 'food code') which emerged in 1963. The Codex Committee on Food Hygiene (CCFH) was charged with the task of developing microbial hygiene standards, although it found itself embroiled in debate with the WHO over the nature these standards should take. The WHO was increasingly relying upon the input of biometricians and especially the International Commission on Microbial Specifications for Foods (ICMSF) which had developed statistical sampling plans for determining the microbial counts in the final end products. The CCFH, however, was initially more focused on a qualitative approach which looked at the entire food production system and developed codes of practice as well as more descriptive end-product specifications which the WHO argued were 'not scientifically correct'. Drawing upon historical archival material (correspondence and reports) from the WHO and FAO, this article examines this debate over microbial hygiene standards and suggests that there are many lessons from history which could shed light upon current debates and efforts in international food safety management systems and approaches
The contribution of international health volunteers to the health workforce in sub-Saharan Africa
This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens
On the relevance of the “genetics-based” approach to medicine for sociological perspectives on medical specialization
This paper draws on a study on the development of medical genetics as a medical specialism in the UK and Canada to reflect on how local and national contexts affect specialty formation. The paper begins by supporting earlier findings in the literature that stress, first, technological innovations as driving specialty formation, and, second, the domination of physicians in the division of medical labour. Beyond this, however, the paper explores the specific circumstances under which geneticists set about turning their work into a medical specialism based on a “genetics-based approach” to illness and how “medical genetics” as a specialism was assessed and configured to fit national and regional health service requirements
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