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An Introduction to the Principles of Toxicology. A Small Dose of Toxicology. ENV H 472 A - ENVIRONMENTAL RISK AND SOCIETY Class 2. Steven G. Gilbert, PhD, DABT www.asmalldoseof.org www.toxipedia.org. A Small Dose of Toxicology. See: www.asmalldoseof.org -- smdose.
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An Introduction to the Principles of Toxicology A Small Dose of Toxicology ENV H 472 A - ENVIRONMENTAL RISK AND SOCIETY Class 2 Steven G. Gilbert, PhD, DABT www.asmalldoseof.org www.toxipedia.org
A Small Dose of Toxicology See: www.asmalldoseof.org -- smdose
www.toxipedia.org A free toxicology encyclopedia and resource center that anyone can edit. Toxipedia provides comprehensive, accurate, and scientifically based information on the hazards and risks of chemical and physical agents, with the goal of advancing human and environmental health. Toxipedia
Toxipediasuite of sites www.ipmopedia.org www.healthyworldtheater.org www.wanmec.org www.wltox.org www.toxipedia.org
LDDI Consensus Statement Scientific Consensus Statement on Environmental Agents Associated with Neurodevelopmental Disorders Developed by the Collaborative on Health and the Environment’s Learning and Developmental Disabilities Initiative November 7, 2007 http://www.iceh.org/LDDI.html
LDDI Consensus Statement Given the established knowledge, protecting children from neurotoxic environmental exposures from the earliest stages of fetal development clearly is an essential public health measure if we are to help prevent learning and developmental disorders and create an environment in which children can reach and maintain their full potential. http://www.iceh.org/LDDI.html
NW Public Health Public Health and the Precautionary Principle By Steven G. Gilbert See: http://healthlinks.washington.edu/nwcphp/nph/ nwph
Precautionary Principle “When an activity raises threats of harm to human health or the environment, precautionary measures should be take even if some cause and effect relationships are not fully established scientifically.” Wingspread Conference, 1998.
Central components • Setting goals (Health indicators) • Taking preventive action in the face of uncertainty • Shifting the burden of responsibility to the proponents of an activity (Who benefits?) • Exploring a wide range of alternatives to possibly harmful actions (Is it necessary?) • Increasing public participation in decision making (transparency of information & environmental justice)
So Many Chemicals so Little Data 2863 above 1 Million pounds 12 or 0.4% good data 21.4% some data 78.2% no data www.preventingharm.org
The Consequences • Nearly 12 million children (17%) under age 18 in the US suffer from one or more developmental disabilities • Learning disabilities – 5-10% of kids in public school • ADHD – 3-6% of all school kids, maybe higher
The First Bioethicist Aldo Leopold "A thing is right when it tends to preserve the integrity, stability, and beauty of the biotic community. It is wrong when it tends otherwise." - Aldo Leopold, 1949, A Sand County Almanac ---------- 1887 - 1948 ----------
Limits on Freedom “An ethic, ecologically, is a limitation on freedom of action in the struggle for existence” Aldo Leopold
“The Commons” The Tragedy of the Commons By Garrett Hardin, Science, 1968
Technical Solutions “It is our considered professional judgment that this dilemma has no technical solution.” The Tragedy of the Commons By Garrett Hardin, Science, 1968
Problems – Solutions? • Lead and kids • Fetal alcohol syndrome • Nuclear disarmament • Bioterrorism • Ocean Fisheries • Persistent chemicals • The Commons
Toxicology Definitions The study of poisons or the adverse effects of chemical and physical agents on living organisms.
Ancient Awareness 399 BC Death of Socrates by Hemlock Socrates was charged with religious heresy and corrupting the morals of local youth. The active chemical used was the alkaloid coniine which, when ingested causes paralysis, convulsions and potentially death.
Historical Awareness From Romeo and Juliet - act 5 Come bitter pilot, now at once run on The dashing rocks thy seasick weary bark! Here’s to my love! O true apothecary! Thy drugs are quick. Thus with a kiss I die. Shakespeare (1564-1616)
Human & Environmental Health “Conditions that ensure that all living things have the best opportunity to reach and maintain their full genetic potential.” Steven G. Gilbert, 1999
What do these have in common? • Hong Kong • Princess Diana • Ambassador to Mexico • Coeur d’Alene, Silver Valley, ID • Tacoma • $100 Billion, $65 Billion • Food, noise, dust • 11,000 to 689,000 Children
Power To Discover The Truth “It is not the truth that makes you free. It is your possession of the power to discover the truth. Our dilemma is that we do not know how to provide that power.” Richard Lewontin (New York Review of Books, Jan 7, 1997)
What Is This? O CH3 CH3 N N 7 1 3 O N N CH3
Risk = Hazard X Exposure Key Words Dose / Response Individual Sensitivity
Paracelsus “All substances are poisons; there is none which is not a poison. The right dose differentiates a poison from a remedy.” Paracelsus (1493-1541)
An Individual View “The sensitivity of the individual differentiates a poison from a remedy. The fundamental principle of toxicology is the individual’s response to a dose.” S. G. Gilbert (1997)
Thalidomide • Introduced in 1956 as sedative (sleeping pill) and to reduce nausea and vomiting during pregnancy • Withdrawn in 1961 • Discovered to be a human teratogen causing absence of limbs or limb malformations in newborns • 5000 to 7000 infants effected • Resulted in new drug testing rules
H H C C OH H H H What Is This? (CH3-CH2-OH)
Greek 2nd BC Lead History Lead Makes the Mind Give Way
Polluting with HG Discharge in Minamata Bay