Workers health effects

In addition, the results of the PSA should be compared with the probabilistic safety criteria when these have been defined for the plant. This should be done for all the probabilistic criteria defined for the plant, including those which address system reliability, core damage, releases of radioactive material, worker health effects, public health effects and off-site consequences such as land contamination and food bans. 

T. N. Blumer and co-workers, eds.. Effect of Nitrates and Nitrites in Food as Related to Health, Institute of Nutrition, University of North Carohna, Raleigh, 1973. 

Hexane is classified as a flammable liquid by the ICC, and normal handling precautions for this type of material should be observed. According to the ACGIH, the maximum concentration of hexane vapor in air to which a worker may be exposed without danger of adverse health effects is 125 ppm benzene is rated at 10 ppm. 

For radiation doses <0.5 Sv, there is no clinically observable iacrease ia the number of cancers above those that occur naturally (57). There are two risk hypotheses the linear and the nonlinear. The former implies that as the radiation dose decreases, the risk of cancer goes down at roughly the same rate. The latter suggests that risk of cancer actually falls much faster as radiation exposure declines. Because risk of cancer and other health effects is quite low at low radiation doses, the iacidence of cancer cannot clearly be ascribed to occupational radiation exposure. Thus, the regulations have adopted the more conservative or restrictive approach, ie, the linear hypothesis. Whereas nuclear iadustry workers are allowed to receive up to 0.05 Sv/yr, the ALARA practices result ia much lower actual radiatioa exposure. 

C. I. Fairchild and co-workers, Health-Related Effects of Different Uentilation Rates in Plutonium Eaboratories, LA-11948-MS, Los Alamos National Laboratory, N.M., 1991. 

In another study of workers exposed to UF, the review of two years of foUow-up medical data on 31 workers who had been exposed to utanium(VI) fluoride and its hydrolysis products following the accidental mpture of a 14-t shipping cylinder in early 1986 indicated that none of the 31 workers sustained any observable health effects from exposure to U even though an exposure limit of 9.6 mg was exceeded by eight of the workers (244). 

Aplastic anemia and leukemia are not the only health effects ascribed to benzene exposure. A number of recent studies have associated benzene exposure with chromosomal changes (aberrations) (118). Other studies have shown abnormalities in porphyrin metabolism and decrease in leucocyte alkaline phosphatase activity in apparendy healthy workers exposed to 10—20 ppm benzene (119,120). Increases in leukoagglutinins, as well as increases in blood fibrinolytic activity, have also been reported and are believed to be responsible for the persistent hemorrhages in chronic benzene poisoning (121,122). 

Human Health Effects. Any assessment of adverse human health effects from PCBs should consider the route(s) of and duration of exposure the composition of the commercial PCB products, ie, degree of chlorination and the levels of potentially toxic PCDF contaminants. As a result of these variables, it would not be surprising to observe significant differences in the effects of PCBs on different groups of occupationally-exposed workers. 

Polymers. Studies to determine possible exposure of workers to residual epichl orohydrin and ethylene oxide monomers in the polymers have been done. Tests of warehouse air where Hydrin H and Hydrin C are stored showed epichl orohydrin levels below 0.5 ppm. Air samples taken above laboratory mixing equipment (Banbury mixer and 6" x 12" mill) when compounds of Hydrin H or C were mixed gave epichl orohydrin levels below detectable limits, and ethylene oxide levels less than 0.2 ppm, well below permissible exposure limits (46). A subacute vapor inhalation toxicity study in which animals were exposed to emission products from compounded Parel 58 suggests that no significant health effects would be expected in workers periodically exposed to these vapors (47). 

Medical monitoring and surveillance programs enable occupational health professionals to identify adverse health effects caused by exposure to hazardous substances and conditions and to discuss plans with site workers, industrial hygienists, safety professionals, and line management to prevent exposures and protect workers. These goals can be accomplished through two objectives ... 

Cross-comparing the risks of various activities is difficult because of the lack of a common basis of comparison, however Cohen and Lee, 1979 provide such a comparison on the basis of loss of life expectancy. Solomon and Abraham, 1979 used an index of harm in a study of 6 occupational harms - three radiological and three nonradiological to bracket high and low estimates of radiological effects. The index of harm consists of a weighting factor for parametric study the lost time in an industry and the worker population at risk. The conclusions were that the data are too imprecise for firm conclusions but it is possible for a radiation worker under pessimistic health effects assumptions to have as high index of harm as the other industries compared. 

Workers exposed to chemicals often experience discomfort and adverse health effects which may progress to occupational disea.ses. Even though working conditions have improved markedly during recent decades, in general... 

The hazards of chemicals are commonly detected in the workplace first, because exposure levels there are higher than in the general environment. In addition, the exposed population is well known, which allows early detection of the association between deleterious health effects and the exposure. The toxic effects of some chemicals, such as mercury compounds and soot, have been known already for centuries. Already at the end of the eighteenth century, small boys who were employed to climb up the inside of chimneys to clean them suffered from a cancer of the scrotum due to exposure to soot. This was the first occupational cancer ever identified. In the viscose industry, exposure to carbon disulfide was already known to cause psychoses among exposed workers during the nineteenth century. As late as the 1970s, vinyl chloride was found to induce angiosarcoma of the liver, a tumor that was practically unknown in ocher instances. ... 

The harmful effects of industrial emissions are not confined to the workers but extend beyond the plant boundary line. Chemically-induced diseases among workers exposed to industrial chemicals are a warning sign of the risks to which a larger population is also being exposed usually the chemical hazards are in principle similar in the occupational and general environment. However, occasionally environmental exposures can be qualitatively different from the occupational environment and may also cause deleterious health effects in the general population. 

After the use of a chemical becomes widespread, new deleterious effects on human health may be observed. In such situations, the occupational limit values will have to be modified. Usually the OELS tend to decrease when more information on the toxicity of a chemical is obtained. Knowledge of the specific features of various chemicals is thus extremely important for planning ventilation of industrial premises. It is important to be especially aware of those chemicals that may cause long-term effects without causing any acute effects. There are also compounds such as isocyanates that are extremely irritating at concentrations as low as 0.5 ppm. However, some workers may become sensitized to isothiocyanates at a concentration of 10 ppb, and therefore this has to be taken into consideration when planning the industrial ventilation. Thus, one has to plan against compounds that can cause serious health effects at concentrations at which their presence cannot be observed by the human senses, i.e., irritation or odor. 

Figure 3-5 graphically depicts the information that currently exists on the health effects of methyl parathion in humans and animals by various routes of exposure. The available literature reviewed concerning the health effects of methyl parathion in humans described case reports of longer-term studies of pesticide workers and case reports of accidental or intentional ingestion of methyl parathion. The occupational exposure is believed to be via the dermal and inhalation routes. The information on human exposure is limited in that the possibility of concurrent exposure to other pesticides or other toxic substances cannot be quantified. 

The nuclear explosions that devastated Hiroshima and Nagasaki killed 100,000 to 200,000 people instantaneously. Probably an equal number died later, victims of the radiation released in those explosions. Millions of people were exposed to the radioactivity released by the accident at the Chernobyl nuclear power plant. The full health effects of that accident may never be known, but 31 people died of radiation sickness within a few weeks of the accident, and more than 2000 people have developed thyroid cancer through exposure to radioactive iodine released in the accident. Even low levels of radiation can cause health problems. For this reason, workers in facilities that use radioisotopes monitor their exposure to radiation continually, and they must be rotated to other duties if their total exposure exceeds prescribed levels. 

Studies of workers and volunteers in experiments have provided most of the data on health effects of inhaled trichloroethylene in humans. Most of the information on reported effects in humans following oral exposure... 

OSHA maintains a list of potential carcinogens. In addition, OSHA sets enforceable permissible exposure limits (PELS) to protect workers against the health effects of exposure to hazardous substances. 

Risk assessment pertains to characterization of the probability of adverse health effects occurring as a result of human exposure. Recent trends in risk assessment have encouraged the use of realistic exposure scenarios, the totality of available data, and the uncertainty in the data, as well as their quality, in arriving at a best estimate of the risk to exposed populations. The use of "worst case" and even other single point values is an extremely conservative approach and does not offer realistic characterization of risk. Even the use of arithmetic mean values obtained under maximum use conditions may be considered to be conservative and not descriptive of the range of exposures experienced by workers. Use of the entirety of data is more scientific and statistically defensible and would provide a distribution of plausible values. 

Schwartz BS John Hopkins University School of Hygiene Public Health, Baltimore, MD Study of the relations among BLLS, DMSA-chelatable lead, bone lead, and health effects (heme synthesis, renal early biologic effects and function, blood pressure, and CNS and PNS function) in lead workers in South Korea National Institute of Environmental Health Sciences... 

Chashschin, V.P., G.P. Artunina, and T. Norseth. 1994. Congenital defects, abortion and other health effects in nickel refinery workers. Sci. Total Environ. 148 287-291. 

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