Developmental toxicity functional abnormalities

Toxicologists nowadays take a broad view of developmental toxicity they consider not only structural but also functional abnormalities to qualify as adverse, as long as they were produced as a result of exposures incurred in utero. Thus, for example, the developmental effects of chronic alcohol abuse by pregnant women, known as fetal alcohol syndrome (FAS), are characterized not only by the presence of certain craniofacial abnormalities, but also by a variety of disabilities such as shortened attention span, speech disorders, and restlessness. Although fully expressed physical deformities included in FAS are associated with heavy drinking, debate continues on the level of alcohol consumption, if any, that is without these more subtle effects on behavior. 

Developmental toxicity, defined in its widest sense to include any adverse effect on normal development either before or after birth, has become of increasing concern in recent years. Developmental toxicity can result from exposure of either parent prior to conception, from exposure of the embryo or fetus in utero or from exposure of the progeny after birth. Adverse developmental effects may be detected at any point in the life span of the organism. In addition to stmcmral abnormalities, examples of manifestations of developmental toxicity include fetal loss, altered growth, functional defects, latent onset of adult disease, early reproductive senescence, and shortened life span (WHO/IPCS 2001b). 

It is assumed that all four manifestations of developmental toxicity (death, structural abnormalities, growth alterations, and functional deficits) are of concern. 

Developmental toxicity Adverse effects on the developing organism. Adverse developmental effects may be detected at any point in the life span of the organism. Major manifestations of developmental toxicity include death of the developing embryo, induction of structural abnormalities (teratogenicity), altered growth, and functional deficiency. 

Reproduction toxicity represents any effect on fertility and reproduction that can adversely affect the continuation of the species. Developmental toxicity is any adverse effect induced during the developmental period, i.e. from conception through puberty. The major manifestations of developmental toxicity inclnde death of the developing oiganism, stmctural abnormalities, altered growth and functional deficiencies. Developmental toxicity can be considered a component of reprodnctive toxicity, and sometimes it is difficnlt to distinguish between effects mediated thiongh the parents versus direct interaction with developmental processes. 

SAFETY PROFILE Poison by intravenous and subcutaneous routes. Moderately toxic by ingestion and intraperitoneal routes. An experimental teratogen. Human systemic effects by ingestion and intraperitoneal routes change in vestibular functions, blood pressure decrease, eosinophilia, respiratory depression, and pulmonary changes. Human reproductive and teratogenic effects by unspecified routes developmental abnormalities of the eye and ear and effects on newborn including postnatal measures or effects. Toxic to kidneys and central nervous system. Has been implicated in aplastic anemia. Experimental reproductive effects. Human... 

Many poisons can disturb mental and rational function leading to behavioral abnormalities. Psychototoxins include phencyclidine, LSD, and fungal toxins. Less commonly, stimulants such as cocaine and amphetamine can cause psychiatric problems. Psychiatric effects of high doses of corticosteroids have also been described. In addition to the developmental retardation, some investigators believe that cognitive impairment, hyperactivity, and perhaps even antisocial behavior may be caused by childhood lead exposure. Public discussion of these subtle toxic effects is highly politicized because childhood exposure to lead still occurs as a risk factor in slums and tenements. 

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