Human health hazards, potential

Relative Risks of Nitrosamines. The mere existence of reproducible variations in carcinogenicity from one nitrosamine to another is directly relevant to the question of potential human health hazards from environmental nitrosamines. The problem of nitrosamines in cooked bacon is a simple and straightforward example. 

Human health hazards assessment is the process of identifying the potential effects that chemical may have on humans who are exposed to it, and of determining the levels at which these effects may occur. Human health toxicity data are compared with data from the exposure assessment module to assess human health risk in the risk characterization module. 

The vast majority of mixture data are obtained from toxicological bioassays on binary combinations of chemicals, with fewer studies on 3 or more chemicals or on whole mixtures (i.e., mixtures of many compounds considered together, some of which may be unidentified). Data from bioassays are useful to identify potential human health hazards, quantify dose-response relationships, and provide the... 

Hsieh DPH Potential human health hazards of mycotoxins in Natori S, Hashimoto K, Ueno Y (eds) Mycotoxins and Phycotoxins 88. Amsterdam, Elsevier, 1989, pp 69-80. 

Intermediate-Duration Exposure. No reliable information is available on the effects of repeated-dose exposure in humans. Limited information is available on the effects of repeated inhalation and oral exposures to 1,1-dichloroethane in animals. The studies reviewed indicate that 1,1-dichloroethane is possibly nephrotoxic, but this effect has only been demonstrated at high doses in one of several species tested. No other toxic effects have been attributed to 1,1-dichloroethane following repeated-dose exposures in animals. An intermediate MRL could not be derived for any routes of exposure. More information on the systemic effects of repeated-dose exposures in animals, particularly by the inhalation route since this is the most likely route of human exposure, would be useful to determine whether nephrotoxic effects observed in one study are an actual result of exposure to 1,1-dichloroethane, to determine if 1,1-dichloroethane reacts like other chlorinated aliphatics (e.g., causes neuro-and liver toxicity), and to more fully assess potential human health hazards from repeated exposure to 1,1-dichloroethane. This latter justification is particularly important since repeated exposure to low levels of 1,1-dichloroethane may be of more concern than short-term exposure to very high levels based on the current use and/or disposal of this chemical. 

Chronic-Duration Exposure and Cancer. No information is available on the effects of chronic exposure to 1,1-dichloroethane in humans. The NCI study reported histopathological examinations for endpoints of systemic toxicity in addition to the neoplastic effects in rats and mice. No MRL can be derived for long-term exposure. Additional chronic toxicity studies particularly by the inhalation route would be useful to fully assess potential human health hazard from long-term exposure to... 

The Owens Lake dusts have been recognized as a potential human health hazard. Remediation elforts have recently been implemented to help mitigate dust generation from the dry lake beds. However, we are not aware of any systematic epidemiological or exposure studies that have been carried out to assess or document the health elfects on people living near Owens Lake. 

We are convinced that these limits do not hold in due consideration the potential ecological damage and the possible human health hazards associated with the presence of asbestos in effluents. In addition it appears that the use of parameters related to the... 

Biomonitoring for human health hazard surveillance typically involves collection of hair, expired air, bodily fluids (blood, urine, saliva, breast milk, semen), feces, epithelial scrapings, exfoliated cells, or, less frequently, tissue biopsies from people known or suspected of being exposed to potential chemical, physical, or biological hazards. These samples are analyzed for toxic chemicals, their metabolites, or biomarker responses. The most commonly used biomarkers in humans are those relating to DNA and chromosomal damage, because these effects contribute to cancer risk. Besides biomarkers of chemical exposure and effects, there are also human biomarkers of tumor formation and susceptibility to toxic... 

Over 80 000 chemicals are listed in the TSCA registry, with 1500-2500 new chemicals added each year 20 000 chemicals are commonly found in the workplace (NIOSH list) with <1% tested for reproductive and developmental hazard potential. It is therefore necessary and appropriate to develop fast, inexpensive, sensitive, and accurate methods to prescreen the plethora of chemicals and concentrate resources on those identified by the screening test(s) as potential human health hazards. However, the mechanisms of action of developmental toxicants appear numerous and frustratingly difficult to identify (see section Mechanisms). 

Franklin, M,R. (1976). Mcthyleii edioxyphenyl insecticide synergists as potential human health hazards. Environ. Health Pet sped. 14, 29 32. 

Salem, Ballantyne, and Katz present the argument that when chemicals are used to control civilian dismrbances, it is necessary to use substances of low health hazard potential and employ delivery methods that carry the minimum potential for injury. This chapter reviews the namre and effects of chemicals used, and proposed for use in peacekeeping operations. Particular attention is given to their operational uses in various circumstances, pharmacology, toxicology, evaluation of safety-in-use, delivery, effects on humans, consequences and medical management of overexposure and injury, and the need for preparedness planning. 

The assoeiation of fungi with mammalian diseases came to the fore in 1960 with the diseovery of the aflatoxins (1.36). The death of turkeys from liver damage having been fed on groundnuts eontaminated with Aspergillus flavus led to the isolation of the highly carcinogenic aflatoxins. These developments are discussed in Chapter 9. It led to the awareness of the potential human health hazards from microbial metabolites and the implications of the presence of other mycotoxins in foodstuffs such as patulin in apple juice and the tri-chothecenes on corn. The development of analytical methods for the detection of mycotoxins has become an important aspect of food science. 

McGregor, D. (2006). Methyl tertiary-butyl ether Studies for potential human health hazards. Crit Rev Toxicol 36, 319-358. 

BIOMEDICAL CRITERIA FOR EVALUATING POTENTIAL IN-USE HUMAN HEALTH HAZARDS OF RIOT CONTROL AGENTS... 

Assessing the Potential Human Health Hazards of Dioxin-Contaminated Soil... 

Although the general toxicity of Ge is low, exposure to germanium can lead to intoxication symptoms in flora, fauna, and humans. Ge products (elixirs, supplements) present a potential human health hazard (Tao and Bolger 1997). 

Perchlorates pose a serious risk to humans because they are unstable and have a tendency to explode spontaneously. They are also human health hazards, with harmful effects on both the brain and the thyroid. They have a tendency to prevent the uptake of iodine by the thyroid, thus interfering with the synthesis of hormones normally produced by that organ. Health officials believe that exposure to perchlorates may cause infertility in women or may have harmful effects on their newborn children. These effects include mental retardation and delays in their normal development. As a consequence, efforts are underway to locate areas where perchlorates may have entered the public water supply causing potential health problems for people living in the region. 

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