Forum on Toxics in Air, Water & the Environment

1. Forum on Toxics in Air, Water & the Environment March 10, 2011 Edgewater Community Council Edgewater Environmental Sustainability Program Thomas J Murphy, PhD Kimberly Frye, MS James Filippini

2. The Bad News • Everything consists entirely of chemicals • All Chemicals are toxic The Good News • Most Chemicals have low toxicity • The risk of a toxic Chemical is in the dose – “The Dose makes the Poison”

3. Toxicity Definitions • The toxicity of a substance is measured in milligrams (mg) of chemical per kilogram (2.2 lbs) of body weight, mg/kg. • Since individuals vary in their susceptibility to different chemicals, toxicity is reported as the dose that is harmful to 50% of the population tested. • For lethality, it is reported as the Lethal Dose in mg/kg for 50% of the population or the LD50

4. Classification of Toxic Chemicals

6. The LD50 of a number of common or known substances

7. What About Small Amounts? For cancer-causing chemicals, it is assumed that even one molecule might cause a cancer For most chemicals there is a No Effects Level below which there is no toxicity • Some Carcinogens: • Benzo[a]pyrene • Radon • Aflatoxin B • Hepatitis B Virus • Estrogen • UV radiation • Human Papillomas Viruses (HPV)

10. Water Treatment

11. Milwaukee not so fortunate

12. “Unidentified plume” in Milwaukee Harbor after MMSD discharged 4.9 bilion gal. of untreated wastewater into Lake Michigan

13. 1993 Milwaukee Water Supply Crypto Infection • 419,000/1.6 mil population • Rivers swelled by rains and snowmelt, transported to Lake and from there intake • High turbidity of raw water overwhelmed plants floc and filtration system • Sources: cattle, slaughterhouses & sewage • Solution: Monitor treated water for turbidity, low turbidity = low likelihood of pathogens

14. Emerging Contaminates • Hexavalent Chromium, of Erin Brockovich infamy • Pharmaceuticals and Personal Care Products (PPCP’s) • Disinfection Byproducts (DBP’s) Most prevalent Trihalomethanes produced when Cl reacts with organic matter. • Carcinogenic VOC’s, Part of EPA’s new strategy to look at groups of chemicals.

15. Hexavalent Chromium • Total Chromium standard set at 0.1 mg/L (includes chromium-6) • EPA working with communities to develop data base • EPA reviewing science as part of risk assessment with intent of developing a MCL drinking water standard.

16. Information on Water supply quality can be found at:

17. Fish Consumption Advisories • PCB driven followed by Hg • Dioxins, chlordane, DDT and others not high enough to warrant advice beyond PCB’s • PCB’s declining trend with unlimited consumption by 2040 • Primary Sources: legacy pollution and atmospheric from urban areas

18. Mercury (Hg) • Elemental Hg not very toxic • Organic form Methylmecury (CH3Hg) Highly toxic. (neurotoxcin) • Hg + anerobic bacteria in sediments = CH3Hg • Biomagnifies in fish

21. Sources of Hg

22. Secondary Metabolites • Natural Chemicals • defense: predators & pathogens • attractants: pollinators & seed-dispersal • plant-plant competition: allelopathy

23. Natural v. Synthetic Chemicals Natural Chemicals • Not tested (e.g. dietary supplements, aflatoxins in peanut & apple mold,) • Most levels in diet are below harmful levels (e.g. cyanide, alkaloids) • Importance of varied diet!

24. Some Known Carcinogens

26. EPA regulations require the following of strict safety precautions to remove lead contamination from buildings. http://www.eps.gov/lead/pubs/steps.pdf

27. Radon is a naturally occurring radioactive gas that is emitted from the decay of uranium in the soil, rock and water. It can get into the air of buildings, offices, schools and homes, and become trapped. EPA studies show that living in a home for a lifetime at the Action Level of 4 pCi/L, seven out of 1,000 people could get lung cancer.Testing is easy and inexpensive, taking only a few minutes to set-up the kit, and exposing it for three to seven days.