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Principles for evaluating the effects of chemicals on the aged population / published under the joint sponsorship of the United Nations Environment Programme, the International Labour Organisation, and the World Health Organization
World Health Organization; International Programme on Chemical Safety ( 1993 )
Abstract

A detailed review of research findings and methodological concepts that can guide efforts to characterize the susceptibility of the aged population to the harmful effects of environmental chemicals. Noting that few, if any, of the hundreds of thousands of environmental chemicals have been tested for increased toxicity in the elderly, the book uses knowledge from the fields of gerontology and toxicology to propose methodological principles for investigating the elderly as a population at special risk. Particular attention is given to methods for determining chronic effects, including cancer, linked to the long-term exposures that may characterize this age group. Findings from close to 700 epidemiological, clinical, and experimental studies were critically assessed. The book has four main chapters. The first introduces and discusses the many complex factors that complicate efforts to link chemical exposure to adverse effects on the health of the elderly. Problems considered include the lack of a unified theory of aging, the inability to distinguish intrinsic aging from either disease or toxic response, and the difficulty of determining exposures and doses that have accumulated over decades. The chapter also categorizes classes of chemicals according to their relevance to the aged population, discusses demographic trends, and points to several distinctive life-style variables in the elderly that influence their susceptibility to environmental chemicals. The second chapter provides a detailed review of age-related changes at the genetic, molecular and cellular level, and in individual tissues, organs and systems. For each organ or system discussed, emphasis is placed on age-related changes in structure which might alter functional responses to environmental insults, including chemicals. The third chapter, focused on the basis of altered sensitivity, explores age-related changes in chemical sensitivity as reflected in altered pharmacokinetics and changes in the pharmacodynamics of the central nervous system, endocrine system, kidney, immune system, and other systems and tissues. Theories for explaining the interactions of chemicals and diseases in the aging organism are also reviewed, together with the influence of modifying factors, such as nutrition, alcohol intake, and smoking. The fourth chapter describes the special methodological requirements that need to be met when investigating the effects of chemicals on the aged population. Guidelines are provided for experimental, epidemiological, and clinical approaches, and for the development of biomarkers of aging. The book concludes that the adverse effects of chemical exposure on the aged population will become a health care issue of growing importance

Chlorobenzenes other than hexachlorobenzene / published under the joint sponsorship of the United Nations Environment Programme, the International Labour Organisation, and the World Health Organization
World Health Organization; International Programme on Chemical Safety ( 1991 )
Abstract

Evaluates the risks to human health and the environment posed by exposure to monochlorobenzene, dichlorobenzenes, trichlorobenzenes, tetrachlorobenzenes, and pentachlorobenzene. These chemicals are produced in huge quantities for use as intermediates in the synthesis of pesticides and in the production of a wide range of consumer and commercial products. A review of data on sources of environmental exposure notes that release to the environment occurs primarily during manufacture and that incineration of chlorobenzenes may lead to the emission of polychlorinated dibenzo-p-dioxins and dibenzofurans. Sections concerned with sources and levels of human exposure conclude that the general population is exposed to the lower chlorinated congeners mainly through inhalation, whereas a greater proportion of the total daily intake of the higher chlorinated compounds is ingested in food; breast-fed babies may receive a higher dose than members of the adult population. Particular concern centres on risks of human exposure arising from the ingestion of contaminated fish and from contaminated indoor air linked to use of these compounds as moth repellents and air fresheners. Because of weaknesses in available studies, the report was unable to predict the environmental impact of low-level contamination with chlorobenzenes, or to identify the mechanisms by which these compounds might enter the food chain. While ambient concentrations are expected to reach toxic levels only in the case of accidental spills or uncontrolled industrial discharge, the report notes the need to avoid discharge of chlorobenzenes into the aquatic environment, as this can result in the build up of persistent residues in sediment or ground water. The most extensive section reviews the large number of experimental studies that have evaluated short-term and long-term effects of exposure to these chemicals, including their carcinogenic, teratogenic, and mutagenic potential. Concerning risks to human health, findings from case reports in occupationally exposed populations point to transient effects on the central nervous system, and irritation of the eyes and upper respiratory tract as the principal health effects of exposure

Mercury : environmental aspects / published under the joint sponsorship of the United Nations Environment Programme, the International Labour Organisation, and the World Health Organization
World Health Organization; International Programme on Chemical Safety; WHO Task Group on Environmental Health Criteria for Mercury: Environmental Aspects ( 1989 )
Abstract

Evaluates the effects of mercury on populations of organisms in the environment. Both natural sources of mercury and sources associated with mining and the burning of fossil fuels are considered. Emphasis is placed on the importance of understanding the many environmental variables that affect the uptake and toxicity of mercury, the numerous factors that influence the susceptibility of different organisms, and the great variations in the physico-chemical properties and environmental behaviour exhibited by different species of mercury. Studies are also evaluated on the basis of whether the doses and exposure routes used are compatible with likely conditions in the field. The most extensive sections present illustrative examples of research into the toxic and sublethal effects of inorganic and organic mercury on microorganisms, aquatic organisms, and terrestrial organisms. For all species considered, mercury is noted to be most hazardous in its methyl form. An evaluation of the effects of mercury in the field concentrates on the effects on ecosystems following sea pollution in Japan and the use of organomercury fungicides as seed dressings in Europe

Alpha- and beta- hexachlorocyclohexanes / published under the joint sponsorship of the United Nations Environment Programme, the International Labour Organisation, and the World Health Organization
World Health Organization; International Programme on Chemical Safety ( 1992 )
Abstract

Evaluates the risks to human health and the environment posed by exposure to alpha- and beta-hexachlorocyclohexanes (HCH). These two isomers are by-products in the manufacturing of lindane, and may be present in this pesticide as impurities. Alpha- and beta-HCH are also present in technical-grade HCH, which is used in agriculture and wood protection. Most environmental releases are linked to the use of technical-grade HCH and to the inappropriate disposal of residues produced when lindane is purified. Alpha- and beta-HCH are evaluated in separate monographs, which cover sources of human and environmental exposure, levels detected in different environmental media, behaviour in the environment, metabolic fate in different organisms, and toxic effects on experimental animals, humans, and plant and animal species. Both isomers are noted to be universal environmental contaminants, with concentrations detected in samples of air, rain water, fresh water, sea water, soil, sediment, and numerous plant and animal species, as well as in several important food items. A review of studies on environmental behaviour and metabolic fate concludes that alpha- and beta-HCH, when compared with lindane, are characterized by a higher bioconcentration in the environment, a slower rate of biodegradation by ultraviolet light, and a slower rate of elimination from organisms. Concerning sources of human exposure, studies show that, in industrialized countries, more than 90% of human intake occurs through the consumption of contaminated food, with the highest concentrations found in fat-containing food items. Current exposures via food are judged to be low and gradually decreasing, supporting the conclusion that these isomers pose no serious health threat to the general public. A review of findings from toxicity studies in laboratory animals identifies growth retardation and effects on the liver and kidney as the major consequences of acute exposure. Although a neoplastic response was observed in some studies, the report concludes that this response is most likely due to a non-genotoxic mechanism. In its concluding section, the report expresses serious concern over the widespread pollution of the environment with these isomers. As neither has any insecticidal action, the report concludes that use of technical-grade HCH products containing high concentrations of alpha- and beta-HCH is never justified

Methods for assessing the effects of chemicals on reproductive functions / edited by Velimir B. Vouk and Patrick J. Sheehan; prepared by Scientific Group on Methodologies for the Safety Evaluation of Chemicals (SGOMSEC)
Vouk, Velimir B; Sheehan, Patrick J; Scientific Group on Methodologies for the Safety Evaluation of Chemicals; International Council of Scientific Unions. Scientific Committee on Problems of the Environment; International Programme on Chemical Safety; Workshop on Methods for Assessing the Effects of Chemicals on Reproductive Function (1981 : Ispra, Italy) ( 1983 )
Aldicarb / published under the joint sponsorship of the United Nations Environment Programme, the International Labour Organisation, and the World Health Organization ; first draft prepared by J. Risher and H. Choudhury
World Health Organization; International Programme on Chemical Safety ( 1991 )
Abstract

Evaluates risks to human health and the environment posed by aldicarb, a carbamate insecticide applied, exclusively in granular form and below the soil surface, to control certain insects, mites, and nematodes. Aldicarb has been approved for use on a wide range of crops; ingestion of contaminated food is the main route of exposure for the general population. Because aldicarb is applied to the subsoil, the evaluation of environmental fate concentrates on mobility and persistence in soil and on the circumstances under which aldicarb may contaminate shallow wells. The rapid uptake of aldicarb and its residues by food crops is another consistently reported finding. Studies in experimental animals point to the efficient absorption of aldicarb from the gastrointestinal tract and its wide distribution to all tissues, including the developing fetus. Concerning risks to human health, the book draws on reports of several widespread outbreaks of aldicarb poisoning following the ingestion of contaminated cucumbers, melons, watermelons, and drinking water. In each of these cases, poisoning resulted from the use of aldicarb on a non-approved crop. The book concludes that aldicarb is one of the most potent and acutely toxic pesticides in use, that most cases of poisoning and toxicity arise from the use of aldicarb on non-approved crops or the failure to follow recommended safety precautions, that the symptoms of poisoning are transient and rarely fatal, and that aldicarb poses no risk to the general population when applied at recommended rates and using current techniques. The need to use protective equipment during manufacture, formulation, and application is stressed

Cadmium / published under the joint sponsorship of the United Nations Environment Programme, the International Labour Organisation, and the World Health Organization
World Health Organization; International Programme on Chemical Safety ( 1992 )
International Workshop on Human Health and Environmental Effects of Motor Vehicle Fuels and their Exhaust Emissions, Sydney, Australia, 6-10 April, 1992 / edited by R. Manuell ... [et al.]
International Workshop on Human Health and Environmental Effects of Motor Vehicle Fuels and their Exhaust Emissions (1992: Sydney, Australia); Manuell, R; Callan, Philip; Bentley, K; McPhail, S; Smith, E; World Health Organization; International Programme on Chemical Safety ( 1993 )
Polychlorinated biphenyls and terphenyls
World Health Organization; International Programme on Chemical Safety ( 1993 )
Abstract

Evaluates the vast body of evidence demonstrating the serious threat to human and environmental health posed by polychlorinated biphenyls (PCBs). These chemicals, which are now ubiquitous in the environment, have been used commercially since 1930 as dielectric and heat-exchange fluids and in a variety of other applications. Over 1,300 studies were critically assessed. The book also contains a brief review of the limited data on polychlorinated terphenyls. A section devoted to the environmental behaviour of PCBs assesses the mechanisms by which these highly persistent chemicals, previously introduced into the environment, are gradually being redistributed towards increased contamination of the marine environment. For the general population, the most important sources of exposure are identified as food items and, for babies, breast-milk. The well-documented signs of poisoning in occupationally-exposed workers are also reviewed. A section devoted to the metabolic fate of PCBs cites evidence of accumulation in the liver and the adipose tissues of various organs, placental transport, fetal accumulation, and distribution to milk. The most extensive section, which runs some 100 pages, evaluates findings from studies of toxicity in experimental animals and in vitro systems. Findings suggest that PCBs are immunosuppressive and act as tumour promoters. An assessment of effects on humans draws upon studies of two large outbreaks of poisoning from contaminated food, and of occupational exposures. Concerning risks to the environment, the report cites reproductive failure in sea mammals as the most important hazard, further concluding that the predicted redistribution of residues towards the marine environment will pose an increasing hazard for sea mammals in the future. A review of the hazards of polychlorinated terphenyls concludes the report

Triphenyl phosphate / published under the joint sponsorship of the United Nations Environment Programme, the International Labour Organisation, and the World Health Organization
World Health Organization; International Programme on Chemical Safety ( 1991 )
Abstract

Evaluates risks to human health and the environment posed by the production and use of triphenyl phosphate, a compound widely used as a flame retardant in phenolic and phenylene-oxide-based resins for the manufacture of electrical and automobile components. Triphenyl phosphate is also used as a non-flammable plasticizer in cellulose acetate for photographic films, and as a component of hydraulic fluids and lubricant oils. Main sources of release into the environment are identified as leakage or spills of hydraulic fluid, leaching from plastics, and manufacturing processes. A review of data on effects on organisms in the environment concentrates on risks to the aquatic environment, concluding that triphenyl phosphate is the most acutely toxic of te various triaryl phosphates to fish, shrimp, and daphnids. The remaining sections evaluate toxic effects as determined through studies in experimental models and observations in humans. The book notes that triphenyl phosphate exhibits low toxicity in short-term studies, is not mutagenic, and has not been shown, in several well-designed studies, to cause delayed neuropathy or other neurotoxic changes. Studies of exposed workers found no evidence of neurological disease or other abnormalities. Risks to the environment are likewise judged to be low, though spills of hydraulic fluid could result in fish kills