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The purpose of this paper is to synthesize chitosan, N-octyl chitosan (NOCh) and carboxymethyl chitosan (CMCh) derivative from prawn shell wastes and identify their applications as modifiers on cellulosic fibres, jute and cotton, to develop quality textile fibres.

Chitosan was obtained by deacetylation of chitin. NOCh was obtained by reductive amination of chitosan. Water-soluble CMCh was prepared by reacting chitosan with monochloroacetic acid in aqueous alkaline media at ambient conditions. Chitosan, NOCh and CMCh were applied on cellulosic fibres, and structure and physico-chemical characteristics of chitosan derivatives and modified fibres were investigated and analysed.

The molecular weight, degree of deacetylation and ash content of prepared chitosan were 1,39,958 Da, 85 and 2.33 per cent, respectively. The moisture content, water holding capacity and total nitrogen content were above 10, 450 and 6.5 per cent, respectively. Average degree of substitution of CMCh was 0.82 as determined by titrimetric analysis. Fourier transform infrared spectroscopy (FTIR) spectra showed characteristic peaks of carbonyl group at 1,659 cm⁻¹, –NH2 at 1,600 cm⁻¹, symmetric stretching of C-H in the methyl group at 1,520 cm⁻¹ and carboxylic group at 1,737 cm⁻¹. Thermograms showed moderate thermal stability in treated fibres compared to untreated fibres. Surface morphology of the modified fibres exhibited smoother surface due to the absorption of chitosan, NOCh and CMCh.

Modification of jute and cotton by sorption of NOCh and CMCh introduced new functional groups on the fibre surface with chemical bonding, which was confirmed by FTIR. Surface morphology of the fibres was carried out by scanning electron microscopy. As the modified fibres also showed good dyeability and colour fastness as well as other properties, the chitosan derivatives as a textile modifier would be helpful to avoid synthetic petroleum-based chemical modifiers as well as to manage the environmental pollution from prawn shell waste and other toxic chemicals.

The purpose of this paper is to investigate the potential for using chitin and chitosan sustainable materials to absorb copper from PCB manufacturing effluent and to report the results of an initial feasibility study aimed at demonstrating proof of concept.

Crab shells and prawn shells, both waste products of the seafood industry, as well as chitosan, were evaluated as potential absorbents for recovering copper present at low levels in the manufacturing effluent produced in a UK‐based PCB manufacturing facility. Various conditions were investigated and efforts were also made to recover absorbed copper via a regeneration process that enabled the metal to be electroplated from solution.

Although only a short feasibility study, conditions were found that enabled copper to be absorbed by the ground crab shells and chitosan and then subsequently recovered by electrowinning to produce the metal.

Although successful as a feasibility study, the experimental work highlighted the large number of variables that need to be investigated and optimised in order to obtain the most efficient copper capture and recovery. Further work needs to be carried out to determine these optimum conditions and to investigate the potential for recovery of other metals from a wider range of solutions.

The paper details how individual treatment technologies can be combined to enable a much more sustainable approach to PCB manufacturing which offers the benefits of reduced effluent metal levels, metal recovery and a novel use for another sector's waste products.

Describes a study to measure the quality of service provided by food‐poisoning surveillance agencies in England and Wales in terms of the requirements of a representative consumer ‐ the egg producing industry ‐ adopting “egg associated” outbreak investigation reports as the reference output. Defines and makes use of four primary performance indicators: accessibility of information; completeness of evidence supplied in food‐poisoning outbreak investigation reports as to the sources of infection in “egg‐associated” outbreaks; timeliness of information published; and utility of information and advice aimed at preventing or controlling food poisoning. Finds that quality expectations in each parameter measured are not met. Examines reasons why surveillance agencies have not delivered the quality demanded. Makes use of detailed case studies to illustrate inadequacies of current practice. Attributes failure to deliver “accessibility” to a lack of recognition on the status or nature of “consumers”, combined with a self‐maintenance motivation of the part of the surveillance agencies. Finds that failures to deliver “completeness” and “utility” may result from the same defects which give rise to the lack of “accessibility” in that, failing to recognize the consumers of a public service for what they are, the agencies feel no need to provide them with the data they require. The research indicates that self‐maintenance by scientific epidemiologists may introduce biases which when combined with a politically inspired need to transfer responsibility for food‐poisoning outbreaks, skew the conduct of investigations and their conclusions. Contends that this is compounded by serious and multiple inadequacies in the conduct of investigations, arising at least in part from the lack of training and relative inexperience of investigators, the whole conditioned by interdisciplinary rivalry between the professional groups staffing the different agencies. Finds that in addition failures to exploit or develop epidemiological technologies has affected the ability of investigators to resolve the uncertainties identified. Makes recommendations directed at improving the performance of the surveillance agencies which, if adopted will substantially enhance food poisoning control efforts.

The Commission appointed jointly by the World Health Organization and the Food and Agricultural Organization continues to plod its weary way towards the establishment of Codex standards for all foods, which it is hoped will eventually be adopted by all countries, to end the increasing chaos of present national standards. We have to go back to 1953, when the Sixth World Health Assembly showed signs of a stirring of international conscience at trends in food industry; and particularly expressed “the view that the increasing use of various chemical substances had … , created a new public health problem”. Joint WHO/FAO Conferences which followed initiated inter alia international consultations and the setting up of the Joint FAO/WHO Codex Alimentarius Commission.

There can be few indeed engaged in tasks of food purity control who do not feel apprehensive at some of the modern trends in food production and preparation, particularly at the ever‐increasing range of chemicals in food, whether as additives or contaminants. Undoubtedly there are many who have strong feelings on the subject, but fears and feelings are not evidence and it is an elementary law in every branch of science—some licence may be traditionally permitted in the Arts—that you do not make a statement of fact without being able to furnish proof of it. It seems wrong, therefore, for anyone to make such statements, however well‐intentioned, as were reported to have been made at a recent rally in London organised by the Animal Machines Action Group of the Animal Defence Society. A speaker is reported to have said “that hormone dyes and pesticides used on battery hens and calves increased the incidence of cancer amongst the people who ate these products. The same thing also increased the incidence of coronary thrombosis. It is a fact, although it has been denied, that some battery chickens are born with hardening of the arteries. People who eat them and their eggs run a risk of the same disease.”

The growing range of EEC Directives and Regulations for food products, some of which have never been subject to statutory control in this country, with compositional standards, and in particular, prescribed methods of analysis — something which has not featured in the food legislative policies here — must be causing enforcement authorities and food processors to think seriously, if as yet not furiously. Some of the prescribed methods of analysis are likely to be less adaptable to modern processing methods of foods and as Directives seem to be requiring more routine testing, there is the matter of cost. Directive requirements are to some extent negotiable — the EEC Commission allow for regional differences, e.g., in milk and bread — but it has to be remembered that EEC Regulations bind Member‐states from the date of notification by the Commission, over‐riding the national law. Although not so frequently used for food legislation, they constitute one of the losses of sovereign power, paraded by the anti‐market lobby. Regulations contain usual clauses that they “shall enter into force on the day following publication in the Official Journal of the European Communities” and that they “shall be binding in their entirety and directly applicable in all Member States”.

Some months ago a national organisation established to keep a watchful eye on the Nation's diet expressed concern over the eating trends of people in what to them appeared to be developing inbalances of necessary nutrient factors and the inadeuacy not so much of calories and energy values but in the nature and quality of main food factors. It was recommended that the national diet should be improved, but the authorities pointed to the National Food Survey results to show that the diet was not deficient; that the average daily intake of protein, vitamins, minerals and overall energy requirements were satisfied; all of which is true for the not‐too‐generous levels set. Even the pensioner households included in the Survey sample appear well‐fed. What causes concern is the year‐by‐year decrease in staple foods consumed—milk, red meat, bread, fresh vegetables—and the heavy reliance on refined, processed foods. In its annual reports on NFS reviews, the BFJ has almost monotonously referred to this downward trend. Individual NFS Reports do not reveal any serious deficiencies, as yet, but in the trend over the years—and herein lies the real value of the Survey and its data—few if any of the changes have been for the better; movements in food groups have tended to be downwards. If these trends continue, the time must surely come when there will be real deficiencies; that substitution within a food group cannot make good essential foods severely rationed by high prices.

Little is known of the actualities or possibilities of corporate social reporting in Thailand. This study aims to move towards an appreciation of this neglected but important area. This survey focuses on the annual reports of Thai companies, and thereby contributes to a tradition of related prior empirical work upon corporate social accounting practices which has to date largely focused upon English‐speaking and Western contexts. Its concern is to gain insights into and to critically appraise various dimensions of these annual reports, so as to construct a critique of corporate social disclosure in Thailand. Pursuing a critical perspective sensitive to the context of Thailand, it is concluded that the various aspects of the Thai accounting disclosure that are analysed are disabling, and more generally that the Thai practices explored fall short of their potential to function as enabling communication.

The earliest law of the adulteration of food imposed divisions among the local authorities of the day in functions and enforcements; most of the urban and rural sanitary authorities possessed no power under the law. Provisions dealing with unfit food — diseased, unsound, unwholesome or unfit for human food — were not in the first sale of food and drugs measure and there duties were wholly discharged by all local authorities. Rural sanitary authorities were excluded from food and drugs law and boroughs and urban authorities severly restricted. Enforcement in the rural areas was by the county council, although local officers were empowered to take samples of food and submit them for analysis to the public analyst. Power to appoint the public analyst for the area was the main criterion of a “food and drugs authority”. The Minister had power to direct an authority with a population of less than 40,000 but more than 20,000 to enforce the law of adulteration.

This Food Standards Committee Report has been with us long enough to have received careful appraisal at the hand of the most interested parties — food law enforcement agencies and the meat trade. The purposes of the review was to consider the need for specific controls over the composition and descriptive labelling of minced meat products, but the main factor was the fat content, particularly the maximum suggested by the Associaton of Public Analysts, viz., a one‐quarter (25%) of the total product. For some years now, the courts have been asked to accept 25% fat as the maximum, based on a series of national surveys; above that level, the product was to be considered as not of the substance or quality demanded by the purchaser; a contention which has been upheld on appeal to the Divisional Court.