Children susceptibility

Fire lighters, moth balls. Children susceptible to toxic effects. Oral nausea, vomiting, diarrhoea, excitement, coma, convulsions. Hepatic... 

Children susceptibility to UFP exposure was supported by this study and, when compared to adult individuals in similar conditions, they had at least two times higher dose rates, even when compared to older individuals. Therefore, special attention should be given to the major sources of ultrafine particles in primary schools in order to... 

Child health data needs relating to susceptibility are discussed in 3.12.2 Identification of Data Needs Children s Susceptibility. 

Studies in animals suggest that, unlike some other phthalate esters, the potential for adverse reproductive or developmental effects following exposure to di-n-octylphthalate by the route most relevant to human exposure (oral) is very low (Foster et al. 1980 Gray and Butterworth 1980 Hardin et al. 1987 Heindel et al. 1989 Mann et al. 1985 Morrissey et al. 1989 NIOSH 1983 NTP 1985 Oishi 1990 Oishi and Hiraga 1980). Therefore, it does not appear that individuals of child-bearing age or embryos/fetuses are likely to be unusually susceptible to the effects of di-n-octylphthalate. No other information is available on populations with above-average susceptibility to di-n-octylphthalate. 

The existence in every human being of a vast array of attributes which are potentially measurable (whether by present methods or not), and probably often uncorrelated mathematically, makes quite tenable the hypothesis that practically every human being is a deviate in some respects. Some deviations are, of course, more marked and some more important than others. If this hypothesis is valid, newborn children cannot validly be considered as belonging in either one of two groups, normal and abnormal. Substantially all of them are in a sense "abnormal." In the majority, the "abnormalities" may be well enough concealed so that they are not revealed by clinical examination, though they may easily have an important bearing upon the susceptibility of the individual child to disease later in life. 

Paradoxically, catnip fed to mice had stimulant effects, with increased rearing, locomotion, and stereotypical behavior, increased susceptibility to chemically induced (picrotoxin and strychnine) seizures, and decreased sleeping time after barbiturate administration (Massoco et al. 1995). The LD50 for nepetalactone in mice was reported to be quite high at 1300 mg/kg (Harney et al. 1978). In chicks, an a cohol extract of catnip had biphasic effects, where low to moderate doses (25-1800 mg/kg) produced sedative effects, while higher doses (>2 g/kg) had less sedative and perhaps stimulant effects (Sherry and Hunter 1979). Humans have reported sedative effects of catnip, and one accidental ingestion by a young child reportedly produced sedative effects (Osterhoudt et al. 1997). 

The concept that infants and children may be a sensitive subgroup relates to their relative immaturity compared to adults. Children, as well as the unborn child, have in some cases appeared to be uniquely vulnerable to toxic effects of chemicals because periods of rapid growth and development render them more susceptible to some specific toxic effects when compared to adults. In addition to such toxicodynamic factors, differences in toxicokinetics may contribute to an increased susceptibility during these periods. It should be noted, however, that during the developmental and maturational periods the susceptibility to exposure to xenobiotics in children may be higher, equal, or even lower than in adults. Except for a few specific substances, not very much is known about whether and why the response to a substance may differ between age groups. It should also be borne in mind that, in terms of risk assessment, children are not simply small adults, but rather a unique population (Nielsen et al. 2001). 

Nielsen, E., I. Thorup, A. Schnipper, et al. 2001. Children and the unborn child. Exposure and susceptibility to chemical substances - An evaluation. Environmental Project No. 589. Copenhagen Danish Environmental Protection Agency, Ministry of the Environment and Energy. http //www2.mst.dk/Udgiv/pubhcations/ 2001/87-7909-574-7/html/default eng.htm... 

Other less obvious factors are also considered while choosing a suture. For instance, the age and health of the patient. An older person in poor health generally requires a longer period to heal, thus for absorbate sutures, the required degradation time needs to be increased. Conversely, for an active child, while the degradation time may be less, the suture may be exposed to more frequent sudden stresses and the body tissues are generally thinner. The presence of immunodeficiency is also an important factor since they are more susceptible... 

Children, because of their small size, are often the most susceptible to many of the naturally occurring toxins, just as they are to other toxicants. The caffeine from a can of cola will have a much bigger effect on a small child than it will on an adult. 

As a result, they are so susceptible to viral and bacterial infections that they rarely survive infancy. In the French scientists research, blood stem cells were removed from an affected child, treated with a retroviral vector carrying a normal docking protein gene, and returned to the child. Nine out of ten children treated in this way developed functional, mature immune system cells, which provided them with protection against infections. News articles proclaimed that a cure had been found. 

The human reproductive process does not fit perfectly into the animal model of reproductive and developmental toxicity. Conditions of the fetal-maternal unit that affect both mother and child have not been adequately addressed in this monograph, although there is some evidence that some of these adverse outcomes, such as pregnancy-induced hypertension, may be related to environmental exposure (Tabacova et al., 1998 Dawson et al., 1999). This is a promising frontier for new research. We have also not dealt with genetic susceptibility to developmental toxicants. Advances in this field may illuminate many of the mysteries of how toxicants act, and on whom. Limited data are available on mechanisms of action (see section 5.2.4). The work on oxidative stress in pregnancy (Tabacova et al., 1998 Hubei,... 

Increased susceptibility of certain segments of the population, e.g., young children, may arise from increased tissue sensitivity, more complete absorption, altered distribution, or less developed or impaired defense mechanisms. The increased sensitivity of the child to lead toxicity is well documented (100, 101). In children, unlike the adult, renal tubular damage and encephalopathy are more common sequelae (76, 100). With arsenic exposure, children show significantly higher concentrations of the element in hair and urine than do adults (62). 

The diamagnetic susceptibility measurements are consistent with the NMR properties of cycloheptatrienes. Pikulik and Childs compared the H NMR chemical shifts of the C(7) proton of 7-substituted cycloheptatrienes and the corresponding 1,4-cycloheptadienes and showed that there was a considerable upfield shift of the resonance of the former protons... 

---