Hazards chronic effects

CHRONIC HEALTH RISKS may cause dryness, cracking and skin irritation affects central nervous systems causes eye irritation optic nerve damage is the predominant hazard chronic effects may be similar to methanol. 

When dispersed as a dust, adipic acid is subject to normal dust explosion hazards. See Table 3 for ignition properties of such dust—air mixtures. The material is an irritant, especially upon contact with the mucous membranes. Thus protective goggles or face shields should be worn when handling the material. Prolonged contact with the skin should also be avoided. Eye wash fountains, showers, and washing faciUties should be provided in work areas. However, MSDS Sheet400 (5) reports that no acute or chronic effects have been observed. 

Health Hazards Information - Recommended Personal Protective Equipment Dust mask goggles or face shield protective gloves Symptoms Following Exposure Inhalation of dust irritates nose and throat. Contact with eyes causes irritation General Treatment for Exposure INHALATION move to fresh air. EYES flush immediately with physiological saline or water get medical care if irritation persists. SKIN flush with water Toxicity by Inhalation (Thresholdlimit Value) Data not available Short-Term Exposure Limits Data not available Toxicity by Ingestion Grade 1 oral LDjq 11.7 g/kg (rat) Late Toxicity Chronic effects in humans are unknown Vapor (Gas) Irritant Characteristics Not pertinent liqidd or Solid Irritant Characteristics Data not available Odor Threshold Data not available. 

One of the prime concerns, apart from acute and subacute toxicity, is the question of whether a product causes chronic effects. In this context, carcinogenicity studies are of cardinal importance. A possible chronic hazard may be indicated by epi-demological studies. Where such investigations are not available, experiments are performed on animals for the duration of their entire life span. The type of application depends on the exposition (perorally, dermally, per inhalation). 

Long-term (chronic) potential hazards of lighter, more volatile, and water-soluble aromatic compounds include contamination of groundwater. Chronic effects of benzene, toluene, and xylene include changes in the liver and harmful effects on the kidneys, heart, lungs, and nervous system. 

Humans are susceptible to the acute toxic effects of 1,2-dibromoethane from various routes of exposure. Except for adverse reproductive effects in men after occupational exposure, chronic effects of 1,2-dibromoethane exposure have not been documented in humans. Based on data derived from animal studies, mechanisms of action of 1,2-dibromoethane at a cellular level, toxicokinetics, and genotoxicity tests, there is a potential for certain adverse health effects in humans exposed chronically to low environmental levels of 1,2-dibromoethane that could exist near hazardous waste sites or areas of former agricultural use. 

The acute hazard to humans from vapor exposure appears to be relatively slight, as ample warning in the form of eye, nose, and throat irritation occurs at low concentrations no chronic effects have been reported in humans. ... 

The enormous cost of multiple-species, multiple-dose, lifetime evaluations of chronic effects has already made the task of carrying out hazard assessments of all chemicals in commercial use impossible. At the same time, quantitative structure activity relationship (QSAR) studies are not yet predictive enough to indicate which chemicals should be so tested and which chemicals need not be tested. In exposure assessment, continued development of analytical methods will permit ever more sensitive and selective determinations of toxicants in food and the environment, as well as the effects of chemical mixtures and the potential for interactions that affect the ultimate expression of toxicity. Developments in QSARs, in short-term tests based on the expected mechanism of toxic action and simplification of chronic testing procedures, will all be necessary if the chemicals to which the public and the environment are exposed are to be assessed adequately for their potential to cause harm. 

Such a dichotomy cannot be resolved in a generic manner. Although it may be advisable that chronic effect results be obtained from both a rodent and nonrodent, the selection of appropriate species for chronic toxicity tests should be based upon practical reasons and the results of previously conducted studies. In some cases, testing with a single species may provide sufficient data for assessing test chemical hazards. Strains of test animals should be well characterized for commonly found diseases and their resistance, and should be free from congenital defects. 

The Panel has also concluded that chronic effects of hazardous waste exposure at Love Canal have neither been established or ruled out yet, in a scientifically rigorous manner. 

Probably the most significant worker health and safety development affecting the coloring of plastics is OSHA s Hazard Communication Standard (HCS).This regulation brings many colorants under regulation due to possible chronic effects of exposure. 

Thus to ensure the safety of food packaging, not only is it necessary to consider the toxicity of any migrating species (hazard evaluation), but also how much is consumed (consumption estimation) and how much is present in the foodstuffs (occurrence estimation) consumed. This approach by Rees and Teimant (1993) is suitable for chemicals that have a chronic effect, but for those that have acute toxic effects the amount of food containing them... 

A5.2.2.9 The competent authority will need to establish what level of risk is acceptable to implement such an approach to consumer product labelling for chronic effects. For example, CPSC recommends labelling for a cancer hazard if the lifetime excess risk exceeds one-in-a-million from exposure during reasonably foreseeable handling and use. ... 

The concerns of the residents intensified in May, 1980 when the EPA announced that a study had found chromosome damage in 11 of 36 Love Canal residents tested. This study had serious scientific flaws but was widely publicized and became the focus of deep debate. The results of the chromosome study, as well as those from the studies of fetal outcomes, were evaluated by an expert panel which was established by the Governor of New York soon after the release of the chromosome damage reports. This expert group, known as the Thomas panel, came to the conclusion that no acute health effects related to exposure to the hazardous wastes had been established and that studies of chronic effects were inconclusive. Not surprisingly, the reactions to this report were mixed and reflected the positions staked out by the various actors in the Love Canal story, including a number of scientists. 

Hazard identification is the step in the risk assessment that qualitatively characterizes the inherent toxicity of a chemical. Scientific data are evaluated to establish a possible causal relationship between the occurrence of adverse health effects and chemical exposure. This step includes characterization of acute, subchronic, and chronic effects the potential for local versus systemic effects the influence of the route of exposure the relevance, to humans, of effects seen in animals an evaluation of the biological importance of the observed effects the likelihood of the effects occurring under certain conditions and the potential implications for public health. This step should be based on a thorough review of all the data that may provide information that is relevant to evaluating the potential chemical hazard. This may include data describing the effects on a variety of test animals, in vitro studies that characterize mechanisms of toxicity, metabolism, physiologically based pharmacokinetic studies, structure-activity relationships, short-term human studies, and epidemiological studies. Animal studies may focus on particular types of effects and may include reproductive toxicity studies,... 

Hazard Chronic manganese poisoning and pulmi-nary effects. TLV 1 mg/m3. 

Although originated for DHHS, the approach has potential for use throughout government when it is necessary to communicate risks to an interested public. This is especially true for pesticides. These chemicals, which are an important part of the armamentarium against that aspect of nature which would take the very bread from our mouths, have acquired a somewhat unsavory reputation because of the potential risk associated with some of their chronic effects. The method chosen to explain the context of a pesticide risk (health hazards, etc.) to the public is a vital part of effective pesticide use management. 

Carcinogenicity Bio-accumulation Hazard to Wildlife and other Chronic Effects... 

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