Effective dose

The W used in calculating the effective dose is proportional to the total detriment given in Table 3.2 and, thus, takes into account fatal cancers and severe hereditary effects, weighted nonfatal cancers, and the relative severity of all fatal responses. When the whole body is irradiated uniformly, the value of wT for a particular organ is the fraction of the total detriment resulting from irradiation of that organ. Thus, the effective dose is intended to be proportional to total 

It also is important to note that the total detriment developed by ICRP (1991) is intended to be used mainly in obtaining wTs in the effective dose (the values of wT in Table 3.4 are roughly proportional to the corresponding total detriments in Table 3.2). However, total detriment is not normally used in estimating responses from a given effective dose. ICRP and NCRP have continued to emphasize fatal cancers as the health effect of primary concern and have used the probability coefficient for fatal cancers of 5 X 10 2 Sv 1 given in Table 3.3 for this purpose. Total detriment is not used in estimating responses because, as noted previously, the detriment due to nonfatal cancers in Table 3.3 is not the probability of a nonfatal cancer and the detriment due to severe hereditary effects is not experienced by exposed individuals. 

ICRP derived the wr values given in Table 1.2 from a reference population of equal numbers of males and females having a wide 

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Classification of the anabolic steroids is based on chemical stmctures and associated actions. A review of the biosynthesis and metabolism of the naturally occurring estrogens and androgens is available (1). Names, descriptions, approval dates, and recommended doses of the commercial products are found in References 1, 8, and 9. Although steroids may be orally active, the FDA approved mode of adrninistration is the subcutaneous implant. Effective dose is lower with implant rather than oral adrninistration. 

In Vivo Properties. The efficacy of dalbaheptides has been assessed ia various models of experimental septicemia ia mice. In general there was good correlation between the ED qS (effective doses which prevent death ia 50% of test animals) and the MICs on test strains. Teicoplanin was very effective, ED q values ranged from 0.11 to 0.72 mg/kg sc administration for septicemias caused by S. pyogenes S. pneumoniae and S. aureu whereas for vancomycin ED qS were from 0.58 to 7.2 mg/kg (33). Eremomycin (52) had therapeutic activity 2—3 times greater than vancomycin. Therapeutic indices... 

Dose—response relationships are useful for many purposes in particular, the following if a positive dose—response relationship exists, then this is good evidence that exposure to the material under test is causally related to the response the quantitative information obtained gives an indication of the spread of sensitivity of the population at risk, and hence influences ha2ard evaluation the data may allow assessments of no effects and minimum effects doses, and hence may be valuable in assessing ha2ard and by appropriate considerations of the dose—response data, it is possible to make quantitative comparisons and contrasts between materials or between species. 

The toxicity of many bleaching chemicals is also reflected in observed effect doses and concentrations. These measures include lowest pubHshed toxic concentration (TC q), concentration that is lethal to 50% of a specified population (LC q), lowest pubHshed lethal dose (LD q), and dose that is lethal to 50% of a specified population (LD q). Some relevant values of these are Hsted in Table 3. 

Where these limits are impracticable having regard to the nature of the work the employer may apply a dose limit of 100 mSv in any period of 5 consecutive months subject to a maximum effective dose of 50 mSv in any single calendar year, and to prior approval by the Radiation Protection Adviser, the affected employee(s), and the Health and Safety Executive. 

Investigate accidents which may have led to persons receiving effective doses in excess of 6 mSv or an equivalent dose greater than 30% of any relevant dose limit. Investigate and report to the authorities loss of materials from accidental release to atmosphere, spillages, theft. The Regulations provide a comprehensive list of notifiable concentrations for each radionuclide isotope. 

Gangoli, S. (ed.) (1999) The Dictionary of Substances and their Effects (DOSE), Royal Society of Chemistry, London. Gibbons, R. (1994) Statistical Methods for Groundwater Monitoring, Wiley. 

They also state that analytical studies of the oxidation products of dichroine-a indicate that the dichroines are quinazoline derivatives, as already indicated by Koepfli et al. for their alkaloids. With the probable exception of dichroine-a, these bases are active against malaria in chicks in the descending order dichroine-y (1), dichroine- (4) dichroidine quinazolone (40) the figures in brackets are effective doses (mgm./kilo.). There are also two neutral substances present, umbelliferone (dichrin-A) and dichrin-B, m.p. 179-181°. 

Median Effective Dose (ED) The statistically derived single dose of a substance that can be expected to cause a defined nonlethal effect in 50% of a given population of organisms under a defined set of e.xperimental conditions. 

Therapeutic index. Ratio between the median lethal dose CLDso) and the median effective dose CED30) of a drug. 

The pharmacological activities of the isomers should be compared in vitro and in vivo in both animals and humans. Separate toxicological evaluation of the enantiomers would not usually be required when the profile of the racemate was relatively benign but unexpected effects - especially if unusual or near-effective doses in animals or near planned human exposure - would warrant further studies with the individual isomers. 

Dioxane is an impurity present in alcohol ethoxy sulfates formed during sulfation of the ethoxylated alcohol. 1,4-Dioxane is a carcinogen in rats and mice [312-314] and has been considered as a possible carcinogen to humans [315-317]. However, the no-effect dose in rats is equivalent to a daily intake of dioxane of 9.6-19.0 mg/kg/day, which corresponds to 0.672 g/day for humans. In other studies it has been determined that the threshold for onset of human toxicity of 1,4-dioxane lies above an intake of 76 mg/kg in adult males [318]. Although it seems to be demonstrated that amounts up to 1000 ppm of... 

A biomarker of susceptibility is an indicator of an inherent or acquired limitation of an organism s ability to respond to the challenge of exposure to a specific xenobiotic substance. It can be an intrinsic genetic or other characteristic or a preexisting disease that results in an increase in absorbed dose, a decrease in the biologically effective dose, or a target tissue response. If biomarkers of susceptibility exist, they are discussed in Section 3.10 Populations That Are Unusually Susceptible. 

Recently, water-soluble protein fractions, isolated from extracts of bone matrix, were incorporated into a collagen matrix and shown to induce bone (67,68) and cartilage formation both in vitro and in vivo (69,70). In the latter studies, in the absence of the collajgen delivery system, the proteins were incapable of inducing cartilage formation in vivo when implanted intramuscularly into mice. The success of this approach appears to depend on delivering the active agents at an effective dose over an extended time period. 

Strictly speaking, toxicity values should be given relative to the values for the desired activity, that is as selectivity values, because absolute toxicity values are not particularly meaningful. For example, if a drug is toxic at 1 pmol kg but the therapeutically effective dose is 0.1 pmol kg the drug is... 

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