What is fetotoxicity?
Cf Fetotoxicity. Injury to the embryo, which may result in death or abnormal development of a part, owing to substances that enter the placental circulation. Want to thank TFD for its existence?
How does developmental toxicity affect the developing fetus?
Developmental toxicity. Once fertilization has taken place, the toxicants in the environment can pass through the mother to the developing embryo or fetus across the placental barrier. The fetus is at greatest risk during the first 14th to 60th day of the pregnancy when the major organs are being formed.
When is the fetus at greatest risk of exposure to toxicants?
The fetus is at greatest risk during the first 14th to 60th day of the pregnancy when the major organs are being formed. However, depending on the type of toxicant and amount of exposure, a fetus can be exposed toxicant at any time during pregnancy.
What are the effects of toxic pregnancy?
Toxicology Adverse effects on the embryo due to a substance that enters the maternal system and crosses the placental barrier; the effects of the substance may be expressed as embryonic death or abnormal development of one or more body systems, and can be deleterious to maternal health.
How does toxicity develop?
The toxicity depends on a variety of factors: dose, duration and route of exposure (see Module Two), shape and structure of the chemical itself, and individual human factors. body by inhalation (breathing), ingestion (eating), or absorption, or by direct contact with a chemical. humans, animals, or plants; a poison.
What is an embryo toxin?
Embryotoxins include mercury compounds, lead compounds and other heavy metals, and organic compounds such as formamide. Teratogens - Agents that can disturb or cause a malformation in the development of an embryo or fetus. Teratogens may cause a birth defect in the child or cause termination of the pregnancy.
What is placental toxicity?
Placental toxicology is a fascinating subject, as it deals with the toxic effects of drugs, chemicals, and biotoxins (hereafter collectively referred as chemicals) on mother, placenta, and fetus.
Which toxicity is any toxic effect that take place during the development of an organism?
The substance that causes developmental toxicity from embryonic stage to birth is called teratogens.
What causes toxicity in pregnancy?
Exogenous effects, like maternal use of tobacco and alcohol and the negative implications on the fetus are well known. So is the effect of environmental toxins which reach the fetus. Toxins are abundant in the environment in which we live and maternal exposure to these will most often affect her fetus.
How do toxins enter the fetus?
If you breathe or swallow some chemicals, they can enter your bloodstream and pass to your baby via the placenta. Your baby can also be exposed to chemicals after they are born through your breastmilk or if they put their fingers in their mouth.
What should placenta look like?
The placenta looks like a disc of bumpy tissue rich in blood vessels, making it appear dark red at term. Most of the mature placental tissue is made up of blood vessels. They connect with the baby through the umbilical cord and branch throughout the placenta disc like the limbs of a tree.
What are the 3 types of toxicity?
Types of toxicity There are generally three types of toxic entities; chemical, biological, and physical. Chemicals include inorganic substances such as lead, hydrofluoric acid, and chlorine gas, organic compounds such as methyl alcohol, most medications, and poisons from living things.
What is an example of toxicity?
A more potent chemical is more toxic. For example, sodium cyanide is more potent than sodium chloride (table salt) since swallowing a smaller amount of cyanide can poison you. The potency and, therefore, the toxicity of a chemical can be affected by its breakdown within the human body.
What is the most common target organ of toxicity?
The central nervous system is the target organ of toxicity most frequently involved in systemic effects. The blood circulation system, liver, kidneys, lungs and skin follow in frequency of systemic effects.
What is the purpose of embryo-fetal developmental toxicology?
The objectives of the embryo-fetal developmental toxicity studies are designed to detect adverse effects on the pregnant female and development of the embryo and fetus consequent to exposure of the female from implantation to hard palate closure.
What is fetal evaluation?
Fetal evaluations consist of fetal body weights and an external examination of variations and malformations. The definitive embryo-fetal developmental toxicity study is conducted per the ICH guidelines. This study follows the dose-range finding study and utilizes a robust sample size with full fetal evaluations, including external, visceral and skeletal examinations. In addition, toxicokinetics can also be assessed during the course of dose administration for appropriate exposure assessment.
What is the term for the substance that causes developmental toxicity from embryonic stage to birth?
The substance that causes developmental toxicity from embryonic stage to birth is called teratogens. The effect of the developmental toxicants depends on the type of substance, dose and duration and time of exposure. The first few weeks of embryogenesis in humans.
How do toxicants affect a pregnant woman?
However, depending on the type of toxicant and amount of exposure, a fetus can be exposed toxicant at any time during pregnancy. For example, exposure to a particular toxicant at one time in the pregnancy may result in organ damage and at another time in the pregnancy could cause death of the fetus and miscarriage. There are a number of chemicals, biological agents (such as bacteria and viruses), and physical agents (such as radiation) used in a variety of workplaces that are known to cause developmental disorders. Developmental disorders can include a wide range of physical abnormalities, such as bone or organ deformities, or behavioral and learning problems, such as a mental retardation. Exposures to some chemicals during pregnancy can lead to the development of cancer later in the life of the child and are called transgenerational carcinogens. Exposure to toxicants during the second and the third trimester of a pregnancy can lead to slow fetal grown and result in low birth weight.
What were the effects of thalidomide on pregnant women?
Thalidomide was extensively used for the treatment of nausea in pregnant women in the late 1950s and early 1960s until it became apparent in the 1960s that it resulted in severe birth defects. Fetus that were exposed to thalidomide while in the womb experienced limb malformation by which the limb were not developed or appeared as stumps. Other effects also seen with thalidomide exposure included deformed eyes and hearts, deformed alimentary and urinary tracts, blindness and deafness. The thalidomide tragedy marked a turning point in toxicity testing, as it prompted United States and international regulatory agencies to develop systematic toxicity testing protocol. The effects of thalidomide led to important discoveries in the biochemical pathways of limb development.
What is the most important time for the action of any teratogenic substances resulting in birth defects?
The embryogenesis is the most crucial time for the action of any teratogenic substances resulting in birth defects. Certain Pathogens are also included since the toxins they secrete are known to cause adverse effects on the development of the organism when the mother or fetus is infected. Developmental toxicology is a science studying adverse ...
What are the chemicals that cause developmental disorders?
There are a number of chemicals, biological agents (such as bacteria and viruses ), and physical agents (such as radiation) used in a variety of workplaces that are known to cause developmental disorders.
What is developmental toxicology?
Developmental toxicology is a science studying adverse developmental outcomes. This term has widely replaced the early term for the study of primarily structural congenital abnormalities, teratology, to enable inclusion of a more diverse spectrum of congenital disorders. Typical factors causing developmental toxicity are radiation, ...
What is the term for the study of adverse effects on the development of an organism resulting from exposure to toxic agents before?
It is the study of adverse effects on the development of the organism resulting from exposure to toxic agents before conception (either parent), during prenatal development, or post-natally until puberty. The substance that causes developmental toxicity from embryonic stage to birth is called teratogens.
embryotoxicity
toxic effects on the embryo of a substance that crosses the placental barrier; see also embryolethality and teratogenesis. adj. adj embryotox´ic.
embryotoxicity
Toxicology Adverse effects on the embryo due to a substance that enters the maternal system and crosses the placental barrier; the effects of the substance may be expressed as embryonic death or abnormal development of one or more body systems, and can be deleterious to maternal health. Cf Fetotoxicity.
