Sink

1. Non-Point Source Microlayer Point Source Air Ground water Hyporheic zones Water Source Sink Epi-benthic Biota Sediments Benthic Bedrock Chemical Fate

2. pore water Water Source Sink Surficial Sediments Epi-benthic Sediment Benthic Bedrock inorganic Chironomid larvae organic Bedrock

3. H Cl Cl C Cl Cl C Cl Dichlorodiphenyltrichloroethane

4. DDT • DDT was banned for sale in the U.S. on January 1, 1973 • In 1993, DDT was the third most frequently detected pesticide on produce entering the U.S. • Prior to its being banned DDT was accumulating in the fat of humans and all other animals including Arctic seals, and Antarctic penguins even though these animals were far removed from any point of application. Further study showed that birds were acquiring high levels of DDT by biomagnification

5. DDT was classified as a suspected occupational carcinogen that should be handled cautiously in the workplace. • Statistically significant correlation between high body burdens of DDT and breast cancer were observed. (Correlation does not establish cause and effect, There is a significant correlation between the number of Baptist ministers in a City and liquor consumption.) • At a site in California people found DDT the size of bowling balls under houses surrounding the site that was abandoned by a chemical company still in business. EPA bought the homes. Sewers leading to the ocean so contaminated they are being cleaned by hand. Hazmat suits and buckets.

6. The California site is a superfund site (Superfund is the federal government’s program to clean up the nation’s uncontrolled hazardous waste sites)and its history is all to reminiscent of other sites around the country. • The Palos Verdes Shelf Superfund site is an area of contaminated sediment off the Palos Verde Peninsula. The contaminated sediment lies in the Pacific Ocean at depths of 50 ft. or more, too deep for human contact. However, the fish found in the Palos Verdes Shelf area contain high concentrations of DDT and PCBs, concentrations that continue to pose a threat to human health and the natural environment. • The U.S. Justice Department and the California Attorney General in 1990 filed suit under the federal Superfund Law, alleging that Montrose Chemical Corporation of California, Aventis CropScience USA, Inc., Chris-Craft Industries Inc. and Atkemix Thirty Seven Inc., either owned or operated a DDT manufacturing plant in Los Angeles County.

7. Montrose Chemical Corp. Was the nation’s largest manufacturer of DDT. From the 1950s to the 1971 tons of DDT were dumped into the sewer system. In 1971, the last year Montrose used the county sewers, an estimated 50,500 lbs. • The settlement (2000) brought the total amount for environmental restoration to $137.5 million. The US and California previously reached similar settlements with County Sanitation District No. 2 of LA which operated the sewers that conveyed the DDT to the ocean; about 150 municipalities that discharged other substances through the sewers; and three other corporate defendants – Potlach, Simpson, and CBS/Westinghouse that discharged PCBs through the sewers and into the ocean. • Some of the DDT and PCB contaminated sediment has been capped. The question that remains is what to do with the rest of the contaminated sediment and will the sediment stay capped? • What to do about the human health risks from contaminated fish.

8. Most of the DDT on Palos Verdes Shelf converted quickly to DDE or DDD, two DDT related compounds. Recent analysis suggests that reductive dechlorination continues for DDT but PCB concentrations are not breaking down. • There are many ways in which capped DDT and PCBs may not stay in place: biological, chemical, and physical processes are being investigated. • The second area of concern is contaminated fish consumption so EPA and the State have undertaken an extensive outreach program. To warn people of the dangers of eating the contaminated fish. The outreach efforts have been conducted in English, Spanish, Cambodian, Chinese, Filipino, Korean, Vietnamese, Chamorro (northern Mariana Islands and Guam), Samoan, Marshallese, and Tongan. Who says we are not a country of emigrants. • Handout ……..

9. Herbicides account for 69% of all pesticides used by American farmers, insecticides 19% and fungicides 12%. Four crops corn, cotton, wheat, and soybeans account for about 70% of the insecticides and 80% of the herbicides used on crops each year. Fungicides are used primarily to treat seeds and to protect fruits and vegetables during the growing season and after harvest. About 20% of the pesticides used each year in the U.S. are applied to lawns, gardens, parks, golf courses, and cemeteries. The average home owner applies about 5 times more pesticide per unit of land area than do farmers. Each year, Americans spend about 1.5 billion dollars on pesticides used on lawns.

10. Bioavailable – term used to describe the availability of chemicals or materials to living organisms. Measurements of total concentrations of chemicals in water or sediments does not necessarily indicate that the chemical measured is in a form that can be taken up by organisms… Bioaccumulation – General term describing a process by which chemicals are taken up by aquatic organisms from the water directly, or through consumption of food containing the chemicals. Bioconcentration – A process by which there is a net accumulation of a chemical directly from water into aquatic organisms (e.g., by gill, epithelial tissue, or through cell walls). Example lead Biomagnification – A process by which there is a net accumulation of a chemical as the chemical passes up through two or more trophic levels. The term implies an efficient transfer of a chemical from food to consumer, so that the residue concentrations increase systematically from one trophic level to the next. Example DDT

11. Biomagnification of a Persistent Pesticide – DDT PPM DDT Residue Water 0.00005 Plankton 0.04 Silverside Minnow 0.2 Sheepshead Minnow 0.9 Pickerel (Predatory Fish) 1.3 Needlefish (Predatory Fish) 2.1 Heron (Bird, feeds on small animals) 3.6 Tern (Bird, feeds on small animals) 3.9 Herring Gull (Scavenger) 6.0 Fish Hawk (Osprey egg) 13.8 Merganser (Fish eating duck) 22.8 Cormorant (Feeds on large fish) 26.4 BMF (Biological Magnification Factor) = 26.4/0.00005 = 528,000 BMF = ratio of concentration in the organism divided by the concentration in the medium.

12. Characteristics of DDT (POP under Stockholm Convention of the U.N.) Class of chemicals – Naturally occurring? - Synthetic or Manmade? Bioaccumulate - Bioconcentrate - Biomagnify - Hydrophilic - Hydrophobic - Lipophilic - Lipophobic - If you go into the field to look for DDT what should you be aware of?

13. DDT refers to a technical grade which is usually composed of: 77.1% p,p’-DDT 14.9 % o,p’-DDT 0.3% p,p’- DDT 0.1 % o,p -DDD 4.0 % p,p’ -DDE 0.1% o,p’ –DDE 3.5% unidentified compounds Mirex to Kepone - mirex is one of the POPs

14. All things are connected Reported by Dr. Paul Ehrlich In the early 1960’s DDT was sprayed on the thatched roofs and vegetation around villages in Borneo to kill mosquitoes and control malaria. The DDT killed the mosquitoes very successfully, but poisoned all the insects which were then eaten by the gecko lizards that inhabited the houses. The geckos accumulated so much DDT that they too died. Moths, which previously had been kept under control by the geckos, ate the palm thatch and caused the roofs to collapse. Village cats ate the geckos and were themselves poisoned allowing rats to descend on the villages unleashing an epidemic of bubonic plague. To kill the rats the government parachuted cats into some of the remote villages. Sometimes actions that are not well thought out have complex and unsuspected consequences.

15. Eco-colonialism Malaria, an old scourge long thought vanquished, has returned to South Africa. In 1931-32 a malaria epidemic killed more than 22,000 people in the region. After health authorities began spraying DDT inside homes to attack mosquitoes that carry the disease, the incidence dropped dramatically. By 1973, South Africa recorded only 331 malaria cases in the entire country, in 1977 a single death. DDT was phased out by industrialized countries-including South Africa-starting in the mid-1970s in favor of the more expensive insecticides called pyrethroids (chrysanthemum flowers). But mosquitoes have developed resistance to these compounds, and malaria is again rampant throughout poor and politically unstable regions of Asia, South and Central America, and sub-Saharan Africa. The WHO says malaria affects up to 500 million people per year and kills about 2.7 million of them, mostly children in sub-Saharan Africa. The South African government has renewed DDT spraying, and malaria cases are dropping. But the back lash has created total uproar. The South Africans say if they don’t use DDT

16. they will have a pandemic disaster. In December 2000 to the beginning of 2001 representatives of more than 100 nations finalized a UN proposal to impose a prohibition or gradual phase out of 12 substances including DDT. The group of 12 chemicals many of them chlorinated hydrocarbons are known as POPs (persistent organic pollutants). Malaria specialists have no quarrel with banning such compounds as chlordane, heptachlor, dieldrin, PCBs, and dioxin that have been linked to cancer and damage to the human nervous, reproductive, and endocrine system. But they argue that DDT is benign in minute quantities necessary to repel mosquitoes. Some two dozen poor nations, and China and India, continue to spray inside buildings. Preventing poor countries from using DDT, they believe smacks of eco-colonialism by rich countries more concerned with theoretical long-term risks to their own environment than with sickness and death in the Third World. They also call this another instance of First World values being imposed globally, regardless of the consequences.

17. H H H 2 3 3’ 2’ H H 4’ 4 5 6 5’ 6’ H H H H Cl Cl Cl Cl Cl Cl Cl Cl Cl Cl 2,2’3,3’4,4’5,5’6,6’-decachlorobiphenyl Cl H 2-monochlorobiphenyl PCBs

18. 209 congeners (distinct formulations) of which 23 seem to be environmentally important. PCBs are a diverse group of organo-chlorines consisting of a biphenyl ring with 10 available positions for chlorination. In general, the half-life of PCBs in the body increases with increasing chlorination, and values have been estimated to range from <1 year to 71 years. However, the most common congeners to which the general population is exposed are characterized by half-lives of 2-6 years. Thus, it may be difficult to determine the complete historical exposure to PCBs, as biological measurements are often collected many years after exposures have occurred. Ingestion of contaminated food products, especially contaminated sport-caught fish, is among the most important pathways of exposure to PCBs. Reproductive factors, including parity (number of times a female has given birth) and breast-feeding, appear to decrease body burdens of PCBs in reproductive-age women.

19. PCBs - Polychlorinated Biphenyls • 1922 Theodore Swann of the Federal Phosphorus Company set up a plant to produce biphenyl for use in heat transfer applications • 1929 Swann developed PCBs • 1930 Monsanto took over production of PCBs which they sold under the name of AROCLOR • 1943 It was reported in an internal Monsanto memo that chlorinated naphthalene and biphenyl were generally highly toxic and should be used with extreme caution • 1966 Dr. Soren Jensen an analytical chemist with the Univ. of Stockholm discovered PCBs in environmental samples while looking for DDT

20. 1970 – Monsanto restricted the sale of PCBs to closed system manufacturers. GE capacitors • 1977 Monsanto discontinued production of PCBs* • PCBs were found in significant quantities in • Transformers and capacitors • Heat transfer applications • Washable wall coverings • Coatings for ironing board covers • Waterproofers and canvas • File casting solutions • Insulating tapes and protective lacquers • Epoxy resins • Carbonless carbon paper • Hydraulic fluids • Plasticizers • *DDT 1973 banned for sale in US

21. Sold under the name Aroclor as Aroclor 1254, Aroclor 1220, etc. where the second part of the number indicates the percent chlorination of the molecule, the higher the number the more chlorinated the molecule. • PCBs are almost everywhere in the US • The U.S. EPA calculated that 91% of all Americans have detectable levels of PCBs in their bodies, and 40.3% have at least 1 ppm • The milk of nursing mothers had detectable levels of PCBs in all samples tested. The average 1.8 ppm gave an infant seven times the amount the FDA permitted in cow’s milk. • Many of the fish stocks of the Great Lakes and numerous of the nation’s river systems became too contaminated to eat because they contained more than 2 ppm (the limit set by the Federal Government controlling the number of fish that should be eaten by individuals).

22. Up to 20 ppm of PCBs have been found in fish from Lake Ontario, far higher than the 2 ppm set by the FDA. Laboratory animals have demonstrated a wide variety of adverse effects of PCBs in laboratory animals, including interference with reproduction, loss of hair, liver ailments, and gastrointestinal lesions. • Dr. James Murphy estimated that almost half of the PCBs which contaminate Lake Michigan were entering the lake through precipitation. • In New York, Michigan, and Texas companies (mid-night dumpers) drained PCBs from transformers, mixed it with crankcase oil and sold the mixture as a dust suppressor for dirt roads. Executives of these companies were sentenced to prison for these activities.

23. In another case PCBs in 55 gallon drums were buried in semi-trailers by companies collecting PCBs from industries for disposal. The collection companies would then dig a ditch, back the semi-trailer into the ditch, remove the tractor, and then bury the trailer and its contents. Big profits if you don’t get caught. Cradle to grave……. Newer laws • In the fall of 1981, New York state hunters were warned to limit their consumption of wild ducks because of PCB contamination, Montana hunters were given the same warning for contamination by Endrin. Dissection of ducks from the Hudson River and Lake Ontario showed contamination levels as high as 7.5 ppm PCBs compared to the 2 ppm limit. It was suggested that no more than two meals of ducks be eaten a month and the skin and fat should be carefully removed. If dressing was fixed with the ducks it was recommended that it should not be eaten.

24. In New York the striped bass fishery had to be shut down (shut down in 1976). Fish and sediments in the upper Hudson River were highly contaminated with PCBs. The source was traced to two closed system manufacturing plants owned by GE that made capacitors. Both facilities had discharge permits from the New York State Department of Conservation. The dilemma of the DOC was how to handle the contaminated sediments. The ultimate decision was to leave them in place, the rationale being that resuspending the fines during dredging would be more detrimental than leaving them in place. GE was fined and the DOC contributed some money to study the problem. The amount contributed by both was only about 20% of the estimated costs to clean it up. The fishery is still shut down as of 2006…. • The first decision to remediate this problem was to allow the natural sediment to cover the contaminated areas.

25. Wednesday Dec. 6, 2000 – EPA proposes a comprehensive plan to clean up the Hudson River and protect public health. The proposal came after 10 years of study. The proposal targets the most contaminated portion of the river and dredging is the recommended option. The plan recognizes the need for stepped up containment of new PCB contamination from active sources. The clean up would remove 100,000 pounds of PCBs that would potentially contaminate people, fish, and wildlife throughout the region. It would reduce health risks and fish contamination by five times immediately following clean-up. The PCB contamination dates back some 30 years ending in 1977 during which GE discharged some 1.3 million pounds of PCBs directly to the river from its facilities in Hudson Falls and Fort Edward, New York.

26. EPA has extensive experience with dredging projects. The proposed clean-up plan calls for dredging the most contaminated areas about 12% of the 40-mile stretch of the Upper Hudson River. The plan calls for the removal of over 2.65 million cubic yards of contaminated sediment, containing 150,000 lbs of total PCBs. Backfilling with clean material, then disposal and on-going monitoring. After treatment the dredged material would be transported away from the river (outside the Hudson River watershed)communities by rail for disposal. The dredging project, which would require GE to pay for it under Superfund law, would take an estimated five years and cost about $460 million.

27. EPA and GE have encountered multiple delays and the project is now scheduled to begin in 2009. With each year of delay another 500 pounds of PCBs wash downstream, over the Federal Dam at Troy to the lower Hudson River, an area that will not be remediated under this clean up. After more than three years of negotiations, on October 6, 2005 a Consent Decree was reached between GE and EPA. Unfortunately this agreement, contrary to the Record of Decision, allows GE to “opt out” of the clean up after the first phase or only 10 percent of the remediation is complete.

28. Short-cakes in the Mid-west were found to contain PCB contamination. • Cattle in Kansas Zebra mussels (Dreissena polymorpha) invaded the Hudson River in about 1990 and are abundant where suitable habitat is found. Especially high average densities (17,000/m2) are found on rocks in waters deeper than 5 m. Zebra mussels have had a profound effect on the ecosystem. Resent estimates suggest that the zebra mussel population of the lower Hudson River may filter a volume of water equal to the entire volume of the tidal freshwater river every 2 days, altering the planktonic community. I addition a recent summer time decline in dissolved oxygen levels can be attributed to the arrival and spread of the zebra mussels. Much research remains to be done on how or if the zebra mussel influences the dynamics of PCB bioaccumulation and transfer through the Hudson River ecosystem.

30. Cl Cl Cl Cl Cl Cl Cl Cl Cl Cl 2,2’3,3’4,4’5,5’6,6’-decachlorobiphenyl Characteristics of PCBs Class of chemicals Naturally occurring? Synthetic or Manmade? Bioaccumulate Bioconcentrate Biomagnify Hydrophilic Hydrophobic Lipophilic Lipophobic

31. Two New Reports Show Industrial Toxins in Human Bodies- World Watch Nov/Dec 2005 Heavy metals, pesticides, solvents, fire retardants, glues, coatings, and combustion emissions are just some of the pollutants absorbed into our bodies on a daily basis, according to two recent studies on human exposure. In the National Report on Human Exposure to Environmental Chemicals, researchers at the U.S. Centers for Disease Control and Prevention (CDC) tested the blood and urine of 2,400 Americans for 148 common chemicals. Among the pollutants found in high levels were cadmium, a heavy metal thought to be absorbed from cigarette smoke and associated with weakened bones and kidney injuries, and phthalates, common plastic softeners that have been linked to diminished reproductive functioning. Although most of the chemicals the CDC tested for existed in concentrations below those believed to be debilitating, the report emphasized the dearth of knowledge about chronic exposure to toxins. On the plus side, the researchers pointed to declines in Americans’ exposure to lead sources such as old paint and to more stringent limits on public smoking. And what else……..? DFS

32. A second study, by the Environmental Working Group (EWG), tested for 413 different pollutants in the umbilical blood of 10 newborn babies. Of the 287 chemicals that were present, 180 are known to cause cancer in humans or animals (hmmmmm OR….). 208 have been shown to contribute to developmental problems, and 217 are toxic to the nervous system. Although embryologists once believed that the placenta protected babies in the womb, they now know that many toxins can filter through, threatening fetuses and newborn babies during sensitive stages of development. Citing pervasive ignorance about the 75,000 chemicals currently manufactured in or imported into the U.S., EWG advocated a more precautionary approach to chemical use. It recommended that the U.S. EPA be given more leeway in demanding safety assessments and that chemical manufacturers be required to demonstrate the safety of their products in the womb. Consumers can also reduce their personal risk by eating organic foods, maintaining a pesticide free household, and limiting use of hygiene products such as hair sprays, cosmetics, and deodorizers. Precautionary principle, 75,000 chemicals, etc. In the face of high levels of uncertainty act conservatively.

33. January 30, 2008 Government promises to rid the nation’s food supply of brain-damaging pesticides aren’t doing the job according to the results of a yearlong study that carefully monitored the diets of a group of local children. The peer reviewed study found that the urine and saliva of children eating a variety of conventional foods from area groceries contained biological markers of organophosphates, the family of pesticides spawned by the creation of nerve gas in World War II (in this study malathion and chlorpyrifos). Overall pesticide marker levels in urine samples were even higher in the winter months, suggesting children may have consumed fruits and vegetables that were imported. The government needs to ensure that imported food comply with the standards we impose on domestic produce. Once you switch from conventional food to organic, the pesticides that the authors can measure in the urine disappear. The level returns immediately when you go back to the conventional diets. Death or serious health problems have been demonstrated in thousands of cases in which there were high-level exposures to malathion and chlorpyrifos. But a link between neurological impairments and low-level exposure is far more difficult to determine.

34. The lead author on this study is Professor Lu from Emory University and a member of US EPA’s pesticide advisory panel. He stated in a press release regarding this peer reviewed journal article, “It is appropriate to assume that if we – human beings– are exposed to this class of pesticides, even though it’s a low-level exposure on a daily basis, there are going to be some health concerns down the road.” “There is a large underpinning of animal research for organophosphate pesticides, and particularly for chlorpyrifos, that points to bad outcomes in terms of the effects on brain development and behavior.” Dr. Theodore Slotkin, a professor of pharmacology and cancer biology at Duke University. Congressional concern that children were being harmed by excessive exposure to pesticides led to the unanimous passage of the Food Quality Protection Act. At its heart was a requirement that by 2006, the EPA complete a comprehensive reassessment of the 9,721 pesticides permitted for use and determine the safe level of pesticide residues permitted for all food products. Handout

35. CH3 C N CH CH3 OC2H5 C C O P CH OC2H5 N CH3 S What have we done to replace things like DDT? One class of chemicals has been developed called organophosphates. Of which Diazinon shown above is an example. O,O,-Diethyl O-(2isopropyl-4-methyl-6-pyrimidinyl) phosphorothioate Acetylcholinesterase inhibitor Action: insecticide and nematicide Use: For soil insects and pests of fruits, vegetables, tobacco, forage, field crops, range, pasture, grasslands, ornamentals. For cockroaches and other household insects including grubs, nematodes in turf, seed treatment and fly control. (Example and calculation)

36. USES Diazinon is a non-systemic insecticide used in agriculture to control soil and foliage insects and pests on a variety of fruit vegetable, nut and field crops. Diazinon is also used on non-lactating cattle in an insecticidal ear tag. Prior to cancellation of all residential uses in by 2004, diazinon was used outdoors on lawns and gardens, indoors for fly control and in pet collars to control fleas and ticks. Diazinon is metabolized within organisms to form diazoxon (sometimes referred to as “activation,) diazoxon is a more potent cholinesterase inhibitor compared to diazinon itself.

37. How many containers 100 yds long x 50 yards wide x 3 yards deep would it take to dilute the diazinon in a quart container of 25% diazinon by weight to the recommended concentration of 80 ng/L. Conversions To Convert From To Multiply by gm mg 1,000 mg ug 1,000 ug ng 1,000 ml gm 1 cc ml 1 qt ml 946.33 liters gallons 0.26417205 gallons ft3 0.13368 ft3 yd3 3.7037x10-2

38. Diazinon – Safe concentration for aquatic life is 80 ng/L although newer research indicates that it might be as low as 8 ng/L. The concentration in 25% diazinon is 25% by weight. One liter contains ___________ ml, and weighs ________________ gms. One quart contains _____________ ml, therefore a quart weighs ________? If one quart weighs ____________ gms and 25% of that is diazinon then one quart contains ________________ gms of diazinon _____________ gm of diazinon = ________________ mg of diazinon _____________ mg of diazinon = ________________ ug of diazinon _____________ ug of diazinon = _________________ ng of diazinon How many liters need to be added to the solution containing ________ ng of diazinon to reduce it to 80 ng/L?

39. __________________ ng = 80 ng/L x = ___________________ liters x To convert liters to gallons multiply by ___________ = ____________ To convert gallons to ft3 multiply by ___________= _____________ One yd3 contains 27 ft3 to convert ft3 to yd3 divide by 27 = __________ How many containers 100 yds long by 50 yds wide x 3 yds deep does it take to dilute the amount of diazinon in a quart or 25% diazinon to 80 ng/L? If it turns out that the “safe” concentration is 8 ng/L how many boxes would it take?

40. What’s Happening with Diazinon Outdoor Use Products? As part of an agreement between U.S. EPA and diazinon manufacturers to phase out and eliminate all residential uses of the insecticide diazinon, retailers can no longer sell diazinon outdoor non-agricultural use products, including home lawn and garden products, after December 31, 2004. It will be illegal for retailers to sell these products after that date. However, consumers may continue to use diazinon products purchased before that date, provided they follow all label directions and precautions. What are my Options as a Retailer? Diazinon manufacturers will repurchase from retailers for formulators any unopened, unused supplies of diazinon outdoor non-agricultural use products after December 31, 2004, and before March 31, 2005. If you have questions or need additional information, contact your distributor. It was possible before diazinon was restricted to agricultural uses, that I could go into the store and buy a one gallon container containing 50% diazinon! RUP……. Or……. RIP?

41. Copper 63.546 x 1 = 63.546 Sulfur 32.066 x 1 = 32.066 Oxygen 15.9994 x 9 = 143.9946 Hydrogen 1.00794 x 10 = 10.0794 Sum 249.686 Formula Weight 249.686 mg of CuSO4•5H2O contains 63.546 mg of Cu++ 10 x Perform a toxicity test on copper starting with CuSO4•5H2O we Need to prepare a 10 mg/L solution of copper. What do we need to know: Atomic weights of each of the elements and the number of each of the elements x = 39.292 mg of CuSO4•5H2O dissolved in 1 liter of water gives a nominal 10 mg/L solution of Cu++

43. Biomonitoring • Using biological material to monitor for the presence of toxicants • “No instrument has yet been made that can measure toxicity! Chemical concentrations can be measured but only living material can be used to measure toxicity.”

44. History Although most of the poisons of the time were of vegetable origin, the sulfide of arsenic and arsenious acid were known to be used. It has been postulated that arsenic was the poison with which Agrippina killed Claudius to make Nero, Emperor of Rome. This postulate is supported by the later used of the same material by Nero in poisoning Britannicus, Claudius’ natural son. The deed was done under the direction of Locusta, a professional poisoner attached to the family. The mixture of fact and legend that surrounds the murder illustrates the practices of the times. A first attempt to kill Britannicus failed but the illness reported contained evidence of all the symptoms of arsenic poisoning. The failure led to suspicion and Britannicus’ family hired a taster (biomonitor). The second, successful, attempt involved a more devious scheme. The arsenic had been placed in cold water and Britannicus was served excessively hot soup. The taster had demonstrated the safety of the soup but it was not retested after the water had been added to cool the soup.

45. Here superstition and legend embellish the story. Nero claimed that Britannicus had died of epilepsy and ordered his immediate burial to prevent others from seeing the blackening of the body believed to occur after poisoning. As the legend has it the corpse was painted with cosmetics to hide the deed, but in a raging rain storm the cosmetics were washed off, revealing Nero’s evil deed. Tasters are one type of biomonitor….. What do you see as its strengths and weaknesses? Name another biomonitor from history?

46. When in Rome Do as the Romans Do From all one reads you get the sense that the Romans liked a good party. Clearly the infrastructure of the Roman Empire was well advanced. The Romans had gone so far as to develop a system to transport sewage. There are a lot of theories about the downfall of the Roman Empire. One of those theories, which is considered by scholars as a reasonable one is of toxicological origin. Does anyone know what that theory might be? California popytrail; coke in pottery; etc.

47. Antagonism and Bioavailability It is clear that the Greeks and Romans made considerable use of poisons, often political. Much legend and myth has grown out of the skill of poisoners and the occupational hazards of political life during the period. One such legend tells of King Mithridates of Pontus, who was so fearful of poisons that he regularly ingested a mixture of 36 ingredients (Galen says it was 54 ingredients) as protection against assassination. On the occasion of his imminent capture by his enemies, his attempt to kill himself with poisons failed because of his successful concoction and he was forced to use his sword held by a servant. From this tale comes the term “mithridatic” referring to an antidotal or protective mixture.

48. Additivity, Antagonism, Synergism Assume one unit of toxicant 1 causes 50% mortality of a test species exposed to it and 1 unit of toxicant 2 causes 50% mortality of the same test species exposed to it. Additivity – If these two toxicants are strictly additive then, 0.5 units of toxicant 1 mixed together with 0.5 units of toxicant 2 should cause 50% mortality to the same test species. Antagonism – If these two toxicants are antagonistic to one another then 0.5 units of toxicant 1mixed with 0.5 units of toxicant 2 should kill less than 50% of the same test species. Synergism – If these two toxicants are synergistic to one another then 0.5 units of toxicant 1 mixed with 0.5 units of toxicant 2 should kill more than 50% of the same test species, i.e. the toxicants facilitate one another. DFS

49. La Voisin – Early Toxicologist The culmination of the practice of poisoning in France is represented by the commercialization of the service by Catherine deShayes, who earned the title of La Voisin before she was decapitated. Under the guise of delivering care to the sick and poor, Catherine tested toxic concoctions, carefully noting the rapidity of the toxic response (the onset of action), the effectiveness of the concoction (potency), the degree of responses of the parts of the body (specificity or site of action), and the complaints of the victim (clinical signs and symptoms). Clearly Catherine must be given credit as perhaps the earliest untrained toxicologist. Her business was dissolved by her execution. Her trial was one of the most famous of those held by the Chambre Ardente, a special judicial commission established by Louis XIV to try such cases with out regard to age, sex, or national origin. La Voisin was convicted of many poisonings, including over 2,000 infants among her victims.

50. Dose - Response Typical frequency distribution for the tolerance concentrations of a population. The area between any two ordinances represents the proportion of subjects having tolerances between those two concentrations.