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A screening method for ranking chemicals by their fate and behaviour in the environment and potential toxic effects in humans following non-occupational exposure
A large number of chemicals are released intentionally or unintentionally into the environment each year. These include thousands of substances that are currently listed worldwide and several hundred new substances added annually (MĂŒcke et al., 1986). When these compounds are used, they can reach microorganisms, plants, animals and man either in their original state or in the form of reaction and degradation products via air, water, soil or foodstuffs. Hence environmental chemicals can occur in practically all environmental compartments and ecosystems. It is not feasible to conduct assessments of human exposure and possible associated health effects for all chemicals. Even if the necessary resources were available, reliable data for a quantitative evaluation are likely to be absent in most cases. This has led to the development of schemes for prioritising compounds likely to be of environmental significance. Such schemes can be used to direct future research efforts towards the prioritised compounds. This study was commissioned by the Department of Health (DH) as part of a broader research activity that aims to identify key priority chemicals of concern to human health at routine levels of environmental exposure. The main pathways of human exposure are shown in Figure 1.1. A review of the principal prioritisation schemes used by different organisations to assess the significance of chemical release into the environment has been conducted by the MRC Institute for Environment and Health (IEH, 2003). This review showed that the approaches used by different organisations vary widely, depending on the initial reasons for which the schemes were developed. The basic information presented in the review was used to develop a simple screening method for ranking chemicals. The model used in this prioritisation scheme is outlined in Figure 1.2. The main purpose in developing the prioritisation scheme for DH was to develop a dedicated priority setting method capable of identifying chemicals in air, water, soil and foodstuffs that might pose a significant risk to human health following low level environmental exposure. The methodology was developed in order to identify compounds that required further assessment and those that had data gaps. More detailed risk assessments were conducted at a later stage on those compounds prioritised as being of high importancea. The screening methodology was developed for âexisting chemicalsâ as these are of greatest concern because data on their toxicity and/or fate and behaviour are often unknownb. The production of a priority list was designed to highlight compounds that required further regulatory measures to reduce exposure of the general population and for which an in-depth risk characterisation would be necessary to assist in the evaluation and implementation of activities for reducing environmental risks. This might include an assessment of the costs of such risks to human health and the costs of reduction measures. As the scheme also aimed to identify data gaps that might warrant further investigation, the application of default categories for chemicals with no data was also considered. The overall aim was to develop a screening methodology that is quick, clear and simple to use and that can easily be revised to take into account new information on compounds as and when it becomes available. a Benzene (IEH Report on Benzene in the Environment, R12); 4,6-dichlorocresol, hexachloro-1,3-butadiene, tetrachlorobenzene, 2,4,6-trichlorophenol (reports to DH; available from MRC Institute for Environment and Health b âExisting Substancesâ are those that were placed in the European Union (EU) market before 1981. Prior to 1981 regulatory requirements were related to products intended for certain uses (e.g. veterinary medicines) and did not require assessment of the hazardous properties of any substance before they were released into the market. For substances placed on the market after 1981 (classified as âNew Substancesâ) there is a legal requirement to conduct such assessments. Regulatory agencies require the collection of extensive documentation for safety before a chemical, for example, can be used in foods or commercial products. IEH Web Report W14, posted March 2004 at http://www.le.ac.uk/ieh/ 4 This report describes how physicochemical properties and toxicological data were incorporated into a screening model to assess the potential fate and transfer of chemicals between different environmental compartments and to predict the potential human exposure to toxic chemicals through the inhalation of contaminated air and the ingestion of water and food. It must be stressed, however, that the method devised is a simple screening process and that a more detailed assessment is necessary to determine the potential transfer through the foodchain of a chemical and the full extent of any adverse health effects. Sections 2 and 4 present the physicochemical properties, toxicological data and algorithms used to screen the compounds. Section 3 summarises the groups of chemicals that were included in the screening process. The results of the prioritisation scheme and comments on their limitations and constraints are presented in Section 5
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Designing sustainable medical devices
Stakeholders in the medical device manufacturing industry are becoming more concerned about the environmental impact of their products and processes. The consumers are also becoming more aware of the negative impact that manufacturers can have on the environment. Government initiatives continue to increase environmental awareness through the development of new policy and legislation, encouraging industry to become more accountable for the environmental impact of their products and operations. The ISO 14001 standard, Environmental Management Systems-Requirements with Guidance for Use, sets guidelines to enable businesses to recognize the environmental effects of their products and processes. Departments can use the tool to set targets to lower the environmental impact and identify areas of high environmental concern when designing, purchasing, and marketing products. Research in these areas will be used to develop the environmental scoring tool to aid in the design of future sustainable medical devices
ï»żThe Rainbow Prim Algorithm for Selecting Putative Orthologous Protein Sequences
We present a selection method designed for eliminating species redundancy in clusters of putative orthologous sequences, to be applied as a post-processing procedure to pre-clustered data obtained from other methods. The algorithm can always zero-out the cluster redundancy while preserving the number of species of the original cluster
Variation in the Ό-opioid receptor gene (OPRM1) moderates the influence of early maternal care on fearful attachment
There is evidence that both early experience and genetic variation play a role in influencing sensitivity to social rejection. In this
study, we aimed at ascertaining if the A118G polymorphism of the k-opioid receptor gene (OPRM1) moderates the impact of early
maternal care on fearful attachment, a personality trait strongly related to rejection sensitivity. In 112 psychiatric patients, early
maternal care and fearful attachment were measured using the Parental Bonding Inventory and the Relationship Questionnaire
(RQ), respectively. The pattern emerging from the RQ data was a crossover interaction between genotype and maternal caregiving.
Participants expressing the minor 118 G allele had similar and relatively high scores on fearful attachment regardless of
the quality of maternal care. By contrast, early experience made a major difference for participants carrying the A/A genotype.
Those who recalled higher levels of maternal care reported the lowest levels of fearful attachment whereas those who recalled
lower levels of maternal care scored highest on fearful attachment. Our data fit well with the differential susceptibility model
which stipulates that plasticity genes would make some individuals more responsive than others to the negative consequences of
adversity and to the benefits of environmental support and enrichment
Structure and tribological performance of diamond-like carbon based coatings for aerospace component processing
Copyright @ 2009 The Surface Science Society of JapanThis work examines diamond-like carbon (DLC) coatings deposited by plasma enhanced chemical vapour deposition (PECVD) as an environmentally friendly alternative to chromium plating in restoration of worn or damaged aircraft components. DLC coatings offer superior mechanical properties; however, high internal stresses and poor
adhesion can prevent the deposition of thick films. This work examines a series of layered structures based on epoxy-resin interlayers with DLC applied as a surface film. Wear testing and examination with scanning electron microscopy and atomic force microscopy lead to the development of an optimum DLC/epoxy system with wear characteristics superior to those of chromium-plated steel. This new coating system has a great potential in restoring aircraft components in a more efficient and environmentally friendly manner.This work is funded via the Engineering and Physical Sciences Research Council (EPSRC)
Pilot study and evaluation of a SMMR-derived sea ice data base
Data derived from the Nimbus 7 scanning multichannel microwave radiometer (SMMR) are discussed and the types of problems users have with satellite data are documented. The development of software for assessing the SMMR data is mentioned. Two case studies were conducted to verify the SMMR-derived sea ice concentrations and multi-year ice fractions. The results of a survey of potential users of SMMR data are presented, along with SMMR-derived sea ice concentration and multiyear ice fraction maps. The interaction of the Arctic atmosphere with the ice was studied using the Nimbus 7 SMMR. In addition, the characteristics of ice in the Arctic ocean were determined from SMMR data
Alternative acceptor materials for organic photovoltaic cells
Synthesis and spectroscopic characterization of perylene derivatives (perylene monoimides and diimides) are reported. The aim of the present work is to investigate the synthesis of these compounds in detail in order to highlight the crucial factors for obtaining a specific class of molecules. The final compounds of the synthetic pathway would be able to mimic the peculiar properties of fullerene derivatives, up to now the best candidates as accepting materials
Contraceptive use and sexual function: a comparison of Italian female medical students and women attending family planning services
Objectives: The aims of the study were to understand how education relates to contraceptive choice and how sexual function can vary in relation to the use of a contraceptive method. Methods: We surveyed female medical students and women attending a family planning service (FPS) in Italy. Participants completed an online questionnaire which asked for information on sociodemographics, lifestyle, sexuality and contraceptive use and also included items of the Female Sexual Function Index (FSFI). Results: The questionnaire was completed by 413 women (362 students and 51 women attending the FPS) between the ages of 18 and 30 years. FSFI scores revealed a lower risk of sexual dysfunction among women in the control group who did not use oral hormonal contraception. The differences in FSFI total scores between the two study groups, when subdivided by the primary contraceptive method used, was statistically significant (pâ<â0.005). Women using the vaginal ring had the lowest risk of sexual dysfunction, compared with all other women, and had a positive sexual function profile. In particular, the highest FSFI domain scores were lubrication, orgasm and satisfaction, also among the control group. Expensive contraception, such as long-acting reversible contraception, was not preferred by this young population, even though such methods are more contemporary and manageable. Compared with controls, students had lower compliance with contraception and a negative attitude towards voluntary termination of pregnancy. Conclusion: Despite their scientific knowledge, Italian female medical students were found to need sexual and contraceptive assistance. A woman's sexual function responds to her awareness of her body and varies in relation to how she is guided in her contraceptive choice. Contraceptive counselling is an excellent means to improve female sexuality
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