CLASSIFICATION OF TOXIC AGENTS Flashcards
toxic agents may be
- chemical
- biological
- physical
Examples of Heavy Metal
- lead
- mercury
- cadmium
- chromium
- arsenic
- beryllium
- nickle
differ from other toxic substances in that they are neither created nor destroyed by humans, but they are capable of affecting the health of humans through the air, water, soil, and food they are found in
heavy metals
Their effect on health could occur through at least two mechanisms: first, by increasing the its presence in air, water, soil, and food, and second, by changing the structure of the chemical.
heavy metals
The EPA defines a pesticide as any substance or mixture of substances intended to prevent, destroy, repel, or mitigate any pest.
agricultural chemicals (pesticides)
types of pesticides
- organophosphats
- organochlorine
- fumigants
- inorganic pesticides
- natural organic pesticides
powerful insectidal
dichloro-diphenyl-trichloroethane (DDT)
inexpensive, stable, easily applied, and highly effective - ideal for crop protection and disease prevention
dichloro-diphenyl-trichloroethane (DDT)
lethal to a wide variety of insects but relatively nontoxic to mammals
dichloro-diphenyl-trichloroethane (DDT)
was having unexpected effects on wildlife
dichloro-diphenyl-trichloroethane (DDT)
By the ________, evidence began to accumulate that indiscriminate use of DDT
1960s
due to dichloro-diphenyl-trichloroethane (DDT) birds such as _________ are disappearing
Peregrine falcons, bald eagles, brown pelicans, and other carnivorous birds
any chemical, of natural or synthetic origin, capable of causing an adverse effect on a living organism
toxicants
a toxicant that is produced by a living organism.
toxins
toxic substances produced by microorganisms that are of high molecular weight and have antigenic properties
microbial toxins
broadly defined to represent the array chemicals derived from many species of cyanobacteria (blue - green bacteria), dinoflagellates, and diatoms
algal toxins
generally heat stable and, therefore, not altered by cooking methods
algal toxins
referred to as secondary plant compounds, are often held to have evolved as defense mechanisms against herbivorous animals, particularly insects and mammals
plant toxins (phytotoxins)
Many of the common drugs of abuse such as cocaine, caffeine, nicotine, morphine, and the cannabinoids are ___
plant toxins
Many chemicals that have been shown to be toxic are constituents of ________ and part of _________
plants ; human diet
usually take the form of venoms that are secreted and released by an animal.
animal toxins
As a _________ evaporates, the vapors may pose a threat to the exposed population
solvent
cutaneous effects, such as defatting and local irritation systemic toxic effects, including effects on the nervous system
solvent
release and propagation of energy in space or through a material medium in the form of waves, the transfer of heat or light by waves of energy, or the stream of particles from a nuclear reactor.
radiation
can occur when radioactive materials are released into the environment as a result of an accident or an act of terrorism.
Radioactive contamination and radiation exposure
80 % of human exposure to radiation comes from natural sources, such as ______ from the sun, ______ from the soil, or _____ in rocks and soil
cosmic radiation ; radon gas ; uranium
Over 50 percent of that natural exposure is due to ____
radon gas
The more -____ one is exposed to, either with short – term exposure or with long – term exposure, the greater the chance for serious health consequences.
radiation
The chance of cancer increases with repeated exposure to _____ over time.
radiation
classic example of toxins produced by puffer fishses
tetrodotoxin
