module 6 Flashcards
anthropogenic vs natural pollution
anthropogenic is pollution that is a result of human influence, natural is volcanos
two main categories for air pollution
particulate matter and gaseous matter
common food contaminant in southeast asia resulting in liver necrosis liver failure did death and liver cancer
aflatoxin B1
major air pollutants
particulate matter - solids or liquid drops, engine exhaust
gaseous air pollutants - carbon monoxide, hydrogen sulfide, carbon dioxide, ozone
sources of air pollution
natural air pollutants - volcanos forest wildfires dust storms
anthropogenic- heating and power, automobiles, industrial processes.
types of insecticides
organichlorine ddt they work but increasing sensitivity of neurons resulting in tremors convulsions and death
organophosphorus - absorbed through skin and leading cause of poisoning in agriculture sector.
organophosphorus toxicity
absorbed through skin very toxic to humans.
they irreversibly inhibit acetylcholinesterase which is responsible for breaking down acetylcholine in the synaptic cleft . this causes an increase in acetylcholine in nervous tissue. decreased heart rate severe difficulty breathing fecal and urinary incontinence and blurred vision and death.
herbicides
agent orange - mimicked plant growth hormones. causes uncontrollable grow
heading to death
paraquat - most widely used herbicides. highly toxic when ingested.
paraquat
one of the most widely used herbicides, highly toxic when ingested. causes cellular damage and when ingested immediate burns to the mouth and stomach. primary target is the lungs. where cellular damage results in the development of fibrous tissue that inhibits the ability to breathe. ingestion of two teaspoons can cause death due to lung damage
agent orange
mixture used in vietnam war. it mimics plant growth hormones. causing uncontrollable growth. causing deaths
binds to argo hydrocarbon receptor which is involved in the expression of many genes required for normal cellular functioning
TCDD manifests as chloracne( severe acne) impairment of liver function and cns function. increases risk of certain cancers and birth defects.
lead exposure sources
old paint
lead acid car batteries , makes lead airborne. ends up in soil
aviation fuel and gas in some countries
lead toxicity
cns - decrease. in appetite, irritability and fatigue
brain damage learning deficits and blindness
PNS - degeneration of motor nerves. loss of coordination m.
kidneys - impaires mitochondria
blood - decreases biosynthesis of heme iron, decreasing lifespan of blood cells. causes anemia.
mercury sources
found in water and air mostly fish
mercury toxicity
mercuric mercury - inhalation through vapours toxic to kidneys
methyl mercury - mercury is converted to methyl mercury by bacteria and fish in water. most toxic form of mercury. 90% is absorbed.
targets CNS enters brain binds to nerve cell proteins and leads to nerve cell death. acute toxicity is irritability numbness and tingling. vision and hearing loss tremor and paralysis. chronic is coma and death
treatment for mercury toxicity
chelating agents such as activated charcoal only for mercuric mercury prevents it from being n absorbed