Organochlorines, organophosphates and carbamates, pyrethroids.
how do insecticides work?
poison the CNS
how do organochlorines and pyrethroid act?
by altering the movement of ions across the nerve cell membranes and changing the ability of the neuron to fire.
how do organophosphates and carbamates act?
at the synapse, altering the transmission of the signal from one cell to the next.
organophosphates and carbamates have the same mechanism of action which is ...
inhibition of acetylcholinesterase, causing ach to remain in the synapse leading to excessive firing of the nerves.
name two herbicides
paraquat (more acutely toxic)
what are the health effects of fungicides
waste material, usually in chemical form, that can cause long-term risk to environment and health
the collection, transport, processing, recycling, reducing or disposal of waste materials
concerning waste management, communities need to:
understand the risks and controls, ensure good communication
... deals with the removal of pollution or contaminants from environmental media such as soil, groundwater, sediment, or surface water for the general protection of human health and the environment or from a site intended for development.
what is remediation based on?
assessment of human health and ecological risks and is subject to regulatory requirements
different toxic wastes
Dioxins - PCDDs (polychlorinated dibenzodioxins)
PCBs - Polychlorinated biphenyls
a large family of related compounds, which differ in number and position of chlorine atoms
why are dioxins dangerous?
are not easily broken down in the environment
accumulate in the soils
bioaccumulate in fat
biomagnify as they pass up the food chain
what are the health effects of dioxins?
cancer, immune sys, reprod. and dev. effects
what is the half life of both dioxins and PCBs?
PCBs health effects
chloracne in workers
abundant man-made chemicals, as plasticizers for PVC
health effects of phtalates
repr. and dev. toxicities
an exogenous substance that alters functions of the endocrine system and consequently causes adverse effects in an organism and its progeny
Endocrine Disrupting Chemicals
mechanisms of endocrine disruption are ...
acting as receptor agonist
acting as receptor antagonist
modifying the metabolism of natural hormones
modifying the number of hormone receptors
modifying the production of natural hormones
modulating hormone levels
EDC important issues
no threshold - any level
EDC dose-response relationship is the most controversial issue