Individual sensitivity

The odor threshold of carbon disulfide is about 1 ppm in air but varies widely depending on individual sensitivity and purity of the carbon disulfide. However, using the sense of smell to detect excessive concentrations of carbon disulfide is unreHable because of the frequent co-presence of hydrogen sulfide that dulls the olfactory sense. 

Individuals differ in their sensitivity to odor. Figure 14-7 shows a typical distribution of sensitivities to ethylsulfide vapor (17). There are currently no guidelines on inclusion or exclusion of individuals with abnormally high or low sensitivity. This variability of response complicates the data treatment procedure. In many instances, the goal is to determine some mean value for the threshold representative of the panel as a whole. The small size of panels (generally fewer than 10 people) and the distribution of individual sensitivities require sophisticated statistical procedures to find the threshold from the responses. 

Caution 2,4-Dinitrochlorobenzene causes severe skin irritation to some individuals. Sensitive persons are advised to wear rubber gloves. 

The thiazide diuretics are contraindicated in patients with known hypersensitivity to the thiazides or related diuretics, electrolyte imbalances, renal decompensation, hepatic coma, or anuria. A cross-sensitivity reaction may occur with the thiazides and sulfonamides. Some of the thiazide diuretics contain tartrazine, which may cause allergic-type reactions or bronchial asthma in individuals sensitive to tartrazine. 

The most important potential complication of phenol-based peels is cardiotoxicity. Phenol is directly toxic to myocardium. Studies in rats have shown a decrease in myocardial contraction and in electrical activity following systemic exposure to phenol [i6]. Since fatal doses ranged widely in these studies, it seems that individual sensitivity of myocardium to this chemical exists. In humans neither sex/age nor previous cardiac history/blood phenol levels are accurate predictors for cardiac arrhythmia susceptibility [17]. 

Effects In Humans. Neither postmortem nor functional cerebrospinal fluid (CSF) studies in humans provide firm evidence for similar, long-term damages or alterations to monoaminergic neurons in chronic stimulant abusers. In part, the lack of demonstrable neurochemical changes may well be due to the obvious preclusion of well-controlled prospective experimentation in humans, as well as to variability in critical variables (e.g., individual sensitivity or pattern of abuse) encountered in clinical research. Possible relationship of the various complications of stimulant abuse including hyperpyrexia, seizure, anoxia, and metabolic exhaustion to neuronal chromatolysis, terminal destruction, and monoamine and enzymatic depletion have not been systematically explored in human autopsy eases. It should be also noted that, under nonperturbed conditions, overt behavioral deficits are rare in... 

Individual sensitivity to coffee drinking may or may not be related to its caffeine content. Other compounds found in coffee are probably responsible, as the same individuals can often drink tea without adverse gastrointestinal effect. 

Capitalizing on self-assembly and nanoscience will enhance the ability to screen drugs for individual sensitivities. Advances in drug discovery, combinatorial synthesis, and screening with sensors that have the ability to detect multitudes of specific genetic matches—marrying microelectronics and self-assembly—are expected to be near-term breakthroughs. Then the creation of advanced forms of in the field or in the office tests for chemical risks, pharmaceutical compatibility, or environmental hazards will be possible. 

One of the reasons for suspecting that variations in parathyroid functioning are great is the fact that experimental animals have striking individual sensitivity to administered hormone. This fact has been noted particularly in dogs which have been used for assay animals. Also, in one study involving humans it was found that four normal individuals had their phosphate clearance increased 60 per cent, 190 per cent, 150 per cent, and 110 per cent, respectively, when 200 units of the hormone was administered intravenously, while two individu-... 

Mayer C. Appenzeller U. Seelbach H. Achatz G. Oberkofler H. Breitenbach M. Blaser K. Crameri R Humoral and cell-mediated autoimmune reactions to human acidic ribosomal P2 protein in individuals sensitized to Aspergillus fumigatus P2 protein. J Exp Med 1999 189 1507-1512. 

Volunteers exposed to vinyl acetate showed a wide variation in individual sensitivity to its irritant effects one of three had throat irritation at 20 ppm for 4 hours, whereas 72 ppm for 30 minutes produced eye irritation in three of four participants. All subjects agreed that they could not work at 72 ppm for 8 hours. 

Recommended dosages of digoxin may require considerable modification because of individual sensitivity of the patient to the drug, the presence of associated conditions, or the use of concurrent medications. In selecting a dose of digoxin, the following factors must be considered ... 

Latex allergy The needle cover of the prefilled syringe contains natural rubber (latex), which may cause allergic reactions in individuals sensitive to this substance. 

The principles of toxicology, dose - response and individual sensitivity, are well illustrated by the metals. Historically, most of the interest and concern was with the obvious effects of metal toxicity such as colic from lead or symptoms of the Mad Hatter from mercury. The emphasis has changed to the more subtle and long-term effects and concern for potentially sensitive individuals. It is now well documented that children exposed to even low levels of lead will have a lowered IQ and other learning difficulties. This knowledge has resulted in significant changes in our use of metals. 

Recommendations depending on individual sensitivity limit exposure to solar radiation (ultraviolet radiation) reduce energy consumption... 

UV radiation illustrates the basic principles of toxicology in that individual sensitivity varies greatly, and it is best to limit your dose (exposure) to control your response. The challenge is to understand and manage the risk and benefits of our individual exposure and resulting acute and long-term effects. 

Solar radiation is a classic example of the principles of toxicology beware of individual sensitivity and dose yourself in a way that limits any adverse response. 

Some radiation is helpful and necessary, as in the case of sunlight, which allows us to see the world. The nonionizing radiation of the sun warms us, but too much ultraviolet radiation can cause sunburn or cancer depending on our individual sensitivity. There is clearly a dose - response relationship between exposure and effect, with individual sensitivity playing an important role. Microwave and radiofrequency radiation are incredibly useful in heating and transmitting information. 

Landi, S., Frenzilli, G., Sbrana, I. Barale, R. (1996a) Modulating factors of individual sensitivity to diepoxy butane sister chromatid exchanges induced in vitro in human lymphocytes. Mutat. Res., 357, 75-82... 

In individual sensitivity studies where two or several models participated, it was demonstrated that there are differences in the model results, reflecting differences in model formulations of chemical and dynamical processes. A main conclusion of the study is that the uncertainty range of the model estimates of large-scale ozone perturbations is approximately a factor two. 

---