
e7329807d8d4f52595daf0f170dbd766.ppt
- Количество слайдов: 52
ELSI & Mercury The Ethical, Legal, and Social Implications of Mercury Steven G. Gilbert, Ph. D, DABT www. asmalldoseof. org A Small Dose of Mercury Toxicology – 10/13/04
Child Health A Small Dose of Mercury Toxicology – 10/13/04
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 A Small Dose of Mercury Toxicology – 10/13/04
“The Commons” The Tragedy of the Commons By Garrett Hardin, Science, 1968 A Small Dose of Mercury Toxicology – 10/13/04
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 A Small Dose of Mercury Toxicology – 10/13/04
Problems – Solutions? Ø Ø Ø Ø A Small Dose of Mercury Lead and kids Fetal alcohol syndrome Nuclear disarmament Bioterrorism Ocean Fisheries Persistent chemicals The Commons Mercury Toxicology – 10/13/04
Hg - Inorganic & Organic Hg Inorganic – Quick Silver Hg CH 3 Organic – Methyl Mercury A Small Dose of Mercury Toxicology – 10/13/04
Hg Facts & Uses • • • Quicksilver 13. 6 times the weight of water Evaporates at room temperature Bacteria change to Methylmercury Amalgam Many Industrial uses (thermometers, chemical reactions, gold mining) A Small Dose of Mercury Toxicology – 10/13/04
Hg – Like Water A Small Dose of Mercury Toxicology – 10/13/04
Hg – Solid Enough to Sit On A Small Dose of Mercury Toxicology – 10/13/04
Ancient Awareness • Alchemy • Medicine - cure syphilis? • Egyptian tomb -1500 BC A Small Dose of Mercury Toxicology – 10/13/04
Greek God Mercury “For then she bare a son, of many shifts, blandly cunning, a robber, a cattle driver, a bringer of dreams, a watcher by night, a thief at the gates, one who was soon to show forth wonderful deeds among the deathless gods. . . ” Description of the birth of the Greek God Mercury A Small Dose of Mercury Toxicology – 10/13/04
Historical Events Occupational Exposure Gold mining. Hatters in the felt industry Magicoreligious & Ethnomedical A Small Dose of Mercury Toxicology – 10/13/04
Historical Awareness A Small Dose of Mercury Toxicology – 10/13/04
Current Ethnic Exposures Magicoreligious & Ethnomedical Esperitismo (spiritual belief Puerto Rico) Santeria (Cuban practice) Voodoo Carried in pouch, spread around house or bed, mixed in bath or burned in devotional candles Some consume orally for indigestion, constipation Injected to ward of evil (see Prasad, EHP 112(13), Sept 2004) A Small Dose of Mercury Toxicology – 10/13/04
Discharge in Minamata Bay A Small Dose of Mercury Toxicology – 10/13/04 HG Polluting with
Fetal Effects of Me. Hg A Small Dose of Mercury Toxicology – 10/13/04
Life-Long Effects of Me. Hg A Small Dose of Mercury Toxicology – 10/13/04
Planting Seed with Mercury A Small Dose of Mercury Toxicology – 10/13/04
Iraq Mothers with Bread A Small Dose of Mercury Toxicology – 10/13/04
Iraq Infant - Effects of Mercury A Small Dose of Mercury Toxicology – 10/13/04
Outbreaks of Me. Hg Poisoning Place Year Cases Minamata 1953 -60 1000 Nigata Guatemala 1964 -65 1963 -65 646 45 Ghana 1967 144 Pakistan 1969 100 Iraq 1956 100 Iraq 1960 1, 002 Iraq On-going 1971 2001 40, 000 ? ? ? A Small Dose of Mercury Toxicology – 10/13/04
Environmental Sources of Mercury • Natural Degassing of the earth • Combustion of fossil fuel • Industrial Discharges and Wastes • Incineration & Crematories • Dental amalgams Hg 0 A Small Dose of Mercury Hg 2+ CH 3 Hg+ Mercury Toxicology – 10/13/04
Coal Fired Plants – Hg Emissions A Small Dose of Mercury Toxicology – 10/13/04
Atmospheric Hg A Small Dose of Mercury Toxicology – 10/13/04
Mercury Release 50 -75% mercury of released in the environment related to human activities A Small Dose of Mercury Toxicology – 10/13/04
Biotransformation of Mercury Inorganic Mercury Discharge Biomethylation Methyl. Mercury Ambient Water Sediments Bioaccumulation Edible Fish Methyl-Mercury In Humans A Small Dose of Mercury Exposure Mercury Toxicology – 10/13/04
The Mercury Cycle A Small Dose of Mercury Toxicology – 10/13/04
Neurobehavioral Effects • Blindness - Deafness • Cerebral Palsy - Seizures • Abnormal reflexes & muscle tone • Retarded motor development • Visual and Auditory Deficits • Delayed motor development • Altered DRH performance A Small Dose of Mercury Toxicology – 10/13/04
Effects On The Brain • Decrease in Brain Size • Cell loss • Disorganization of cells • Cell migration failures A Small Dose of Mercury Toxicology – 10/13/04
Animal - Risk Assessment Ø MONKEY - 25 µg/kg - LOAEL Ø RAT - 10 µg/kg - LOAEL Ø RAT - 50 µg/kg - replicated A Small Dose of Mercury Toxicology – 10/13/04
Animal - Risk Assessment Ø 2. 5 µg/kg - NOAEL (animals) Ø 0. 25 µg/kg - Human Ø 0. 025 µg/kg - Sensitive populations (the rule of dividing by 10) A Small Dose of Mercury Toxicology – 10/13/04
Human - Risk Assessment • 10 -20 ppm hair - LOAEL • • 40 -80 ppb blood - LOAEL • • 0. 645 µg/kg • • 0. 06 µg/kg - Rf. D • A Small Dose of Mercury Toxicology – 10/13/04
Me. Hg Consumption Limits US EPA – Rf. D 0. 1 ug/kg-day US FDA – 1 ppm (mg/kg) fish NAS – blood Hg <5. 0 µg/L hair <1. 0 µg/g A Small Dose of Mercury Toxicology – 10/13/04
Hg in Newborns “Based on the distribution of Blood Hg concentrations among the adult female participants in 1999 -2000 NHANES and the number of U. S. births in 2000, > 300, 000 newborns each year in the United States may have been exposed in utero to methyl mercury concentrations higher than those considered to be without increased risk of adverse neurodevelopmental effects associated with methyl mercury exposure. ” Mahaffey et al. Environ Health Perspect 112: 562 -570 (2004). A Small Dose of Mercury Toxicology – 10/13/04
Cost of Childhood Disorders Lead exposure Asthma Cancer Neurobehavioral Total costs $43. 4 Billion $ 2. 0 Billion $ 0. 3 Billion $ 9. 2 Billion $54. 9 (48. 8 -64. 8) Billion Environmental Pollutants and Disease in American Children: Estimates of Morbidity, and Costs for Lead Poisoning, Asthma, Cancer, and Developmental Disabilities, by Landrigan, P. et al. EHP, 110, July 2002, 721 -728. A Small Dose of Mercury Toxicology – 10/13/04
Mercury Fishing Advisories Ø In 2000, 41 States have over 2000 fish consumption advisories Ø An increase from 27 in 1993 Ø Pregnant women, nursing mothers, women who intend to have children, and children under 15 A Small Dose of Mercury Toxicology – 10/13/04
WA State Advisory Limit the amount of canned tuna you eat, based on your bodyweight. Guidelines are: Women of childbearing age should limit the amount of canned tuna they eat to about one can per week (six ounces. ) A woman who weighs less than 135 pounds should eat less than one can of tuna per week. Children under six should eat less than one half a can of tuna (three ounces) per week. Specific weekly limits for children under six range from one ounce for a twenty pound child, to three ounces for a child weighing about sixty pounds. http: //www. doh. wa. gov/fish/Fish. Adv. Mercury. htm A Small Dose of Mercury Toxicology – 10/13/04
WA State Hg CAP WA State Mercury Chemical Action Plan • • Reduce Hg in fish Reduce Hg release into the environment 4 -5 tons of Hg released in WA Educating consumers about Hg in home http: //www. ecy. wa. gov/biblio/0303001. html http: //www. ecy. wa. gov/programs/eap/pbt/mercuryplan. html A Small Dose of Mercury Toxicology – 10/13/04
Hg CAP and Trade U. S. EPA Produced “First-Ever Rule to Reduce Mercury Emissions from Power Plants” • Last 15 years no drop in Hg emissions from power plants • Is Cap and Trade appropriate for a demonstrated neurotoxic compound? A Small Dose of Mercury Toxicology – 10/13/04
Precautionary Principle "When an activity raises threats of harm to the environment or human health, precautionary measures should be taken even if some cause and effect relationships are not fully established scientifically. " - Wingspread Statement on the Precautionary Principle, Jan. 1998 A Small Dose of Mercury Toxicology – 10/13/04
Safety & Efficacy vs Harm Ø FDA regulations of Drugs (1938) Ø FDA regulations of Dietary Supplements (Dietary Supplement Health and Education Act of 1994 (DSHEA)) Ø Ephedra present an unreasonable risk of illness or injury (Dec, 2003) A Small Dose of Mercury Toxicology – 10/13/04
Central components • Taking preventive action in the face of uncertainty • Shifting the burden of proof / responsibility to the proponents of an activity • Exploring a wide range of alternatives to possibly harmful actions • Increasing public participation in decision making Wingspread Conference, 1998. A Small Dose of Mercury Toxicology – 10/13/04
Seattle Initiative City Comprehensive Plans • Every citizen of Seattle has an equal right to a healthy and safe environment. • Seattle sees the Precautionary Principle approach as its policy framework to develop laws for a healthier and more just Seattle. A Small Dose of Mercury Toxicology – 10/13/04
Knowledge - Responsibility • Children have a right to a safe, fair and healthy environment • Ethical Responsibility to share and use of knowledge • Duty to promote health and well being of children • Thoughtful public health advocate A Small Dose of Mercury Toxicology – 10/13/04
Socially Responsible Actions • Testifying • Writing review papers • K-12 class room teaching • Adding expertise to community groups • Education • Mentoring • Speakers Bureau A Small Dose of Mercury Toxicology – 10/13/04
Mercury A Global Issue Mercury distribution and exposure is a global problem A Small Dose of Mercury Toxicology – 10/13/04
Alice’s Adventures “Everything’s got a moral, if you can only find it” Lewis Carroll in Alice’s Adventures in Wonderland A Small Dose of Mercury Toxicology – 10/13/04
The Potential of Children A Small Dose of Mercury Toxicology – 10/13/04
A Small Dose of ™ Mercury A Small Dose of Mercury Toxicology – 10/13/04
Additional Information Ø Web Sites • • • A Small Dose of Mercury World Health Organization - global prospective on mercury health effects. http: //www. who. int/water_sanitation_health/GDW Q/Chemicals/mercuryfull. htm US EPA - Main site on Mercury. http: //www. epa. gov/mercury/ The Mercury Policy Project (MPP). - works to raise awareness about the threat of mercury contamination - http: //www. mercurypolicy. org/ Mercury Toxicology – 10/13/04
Authorship Information This presentation is supplement to “A Small Dose of Toxicology” For Additional Information Contact Steven G. Gilbert, Ph. D, DABT E-mail: smdose@asmalldoseof. org Web: www. asmalldoseof. org A Small Dose of Mercury Toxicology – 10/13/04