1. Secondary Routes of Exposure to Biocides Rolf Halden, PhD, PE Johns Hopkins University Center for Water and Health Bloomberg School of Public Health Baltimore, MD Presented to the Food and Drug Administration (FDA) Nonprescription Drugs Advisory Committee, Silver Spring, MD, on October 20, 2005

2. Overview Background Primary exposures Secondary exposures –Biocides in aquatic environments –Biocides in terrestrial environments Biocides in food, drinking water, human milk, blood, and urine Summary

3. Properties of Important Environmental Contaminants Toxic Large quantities Environmentally persistent Exposure routes exist Difficult to detect

4. Accordingly, Polychlorinated Biocides May Be Problematic Triclocarban (TCC)Triclosan (TCS) PropertyTriclosanTriclocarban Year Introduced19641957 FormulaC 12 H 9 Cl 3 O 2 C 13 H 9 Cl 3 N 2 O Molecular Weight289.55315.59 Water Solubility (mg/L at 25ºC)1.97 – 4.60.65 – 1.55 Log K OW (at 25ºC, pH 7)4.84.9 For each molecule in water, we expect to find ~100,000 in fat

5. Triclocarban: A chemical running under the radar Publications per year

6. Known / Potential Environmental and Human Health Risks of Triclosan Triclosan Degradates (including chloroform) Cross-resistance to Antibiotics Endocrine Disruption ? Acts as Carcinogen, Mutagen or Teratogen (No, at least not directly) Bioaccumulation Persistent Environmental Contaminant Impurities

7. Known / Potential Environmental and Human Health Risks of Triclocarban Triclocarban Cross-resistance to Antibiotics ? Endocrine Disruption ? Acts as Carcinogen, Mutagen or Teratogen ? (Plausible Connection) Bioaccumulation ? Persistent Environmental Contaminant Impurities ? Degradates

8. Biocides Are Persistent Environmental Pollutants Estimated using quantitative structure activity relationship (QSAR) analysis 1 60 120 540 0.75 0.1 1 10 100 1000 10000 AirWaterSoilSediment Estimated Half-life (days) Triclosan Triclocarban Halden and Paull, 2005, ES&T 39(6):1420-1426

9. Overview Background Primary exposures Secondary exposures –Biocides in aquatic environments –Biocides in terrestrial environments Biocides in food, drinking water, human milk, blood, and urine Summary

10. Ingestion Absorption (Inhalation) Primary Human exposure Sources of Biocides: Personal care products Plastics Textiles Laundry detergents Others Co-exposure Manufacturing byproducts Routes of Primary Exposure

11. Wastewater WWTP Sludge Effluent Water resources Air Drinking water Sediment Soil Ingestion Absorption (Inhalation) Secondary Food (Plants and Animals) Bioconcentration Bioaccumulation Biomagnification Human exposure Co-exposure Degradates & Metabolites Routes of Secondary Exposure Disposal

12. Overview Background Primary exposures Secondary exposures –Biocides in aquatic environments –Biocides in terrestrial environments Biocides in food, drinking water, human milk, blood, and urine Summary

13. Triclocarban: 48 Years of Usage Before the First Publication on Its Environmental Fate

14. Isotope Dilution Liquid Chromatography Electrospray Ionization Mass Spectrometry Relative Intensity (%) Triclocarban 313 315 317 373 375 377 HN O H N Cl Cl Cl HN O H N Cl Cl Cl 313 315 317 373 375 377 380 C C 320 322 382 384 324 C C HN O H N l l Cl D D D HN O H N l l Cl D D D D D D D 320 322 382 384 324 325 350375 400300 m/z [M-H] - [M-H+60] - Halden and Paull, Environ. Sci. Technol., 38(18):4849-4855 (2004)

15. TCC Contamination in Baltimore Streams Halden and Paull, 2005, Environ. Sci. Technol., 39(6):1420-1426

16. Co-Occurrence of TCC and TCS in MD Streams TCC [ng/L] TCS [ng/L] R 2 = 0.9882 Measure TCS Calculate TCC Halden and Paull, 2005, Environ. Sci. Technol., 39(6):1420-1426

17. Prediction: TCC Contamination Nationwide

18. Model Predicts Nationwide Contamination Halden and Paull, 2005, Environ. Sci. Technol., 39(6):1420-1426

19. Predictions for 85 Streams Across the U.S. Halden and Paull, 2005, Environ. Sci. Technol., 39(6):1420-1426

20. Toward an Inventory of Biocides in U.S. Water Resources Nationwide

21. Jochen Heidler: Initial Data from the U.S. River samples taken upstream and downstream of WWTPs in 9 states across the U.S. Sapkota, Heidler, and Halden (In Review)

22. Preliminary Results ModelExperimental Upstream Downstream Number of samples 851818 Detection Frequency 60%56% 100% Mean [ng/L] 213 12±15 84 ±109 Predicted Nationwide Contamination Was Confirmed Experimentally Sapkota, Heidler, and Halden (In Review) However, concentrations are low, in the ng/L range!

23. Overview Background Primary exposures Secondary exposures –Biocides in aquatic environments –Biocides in terrestrial environments Biocides in food, drinking water, human milk, blood, and urine Summary

24. Typical U.S. Wastewater Treatment Plant (WWTP) Activated sludge WWTP 680 ML/d (180 MGD) Population served: 1.3 Million Heidler and Halden, 2004

25. Schematic Overview of Studied Activated Sludge Wastewater Treatment Plant (WWTP) Influent Mechanical Screens Primary Clarifiers Activated Sludge Treatment Secondary Clarifiers Sand Filters Effluent Primary Sludge Chlorine Anaerobic Digesters Sludge Thickeners Air Dewatered digested sludge Solid Waste Secondary Sludge Sampling Locations Heidler and Halden, 2004

26. WWTP: Less Than 1 ppb in Effluent 1 10 100 1000 10000 100000 InfluentEffluentDigested Sludge TCS TCC ppb < 1 ppb Accumulation Heidler and Halden (In Preparation) Heidler and Halden (2004 Preliminary Estimate)

27. But Substantial Accumulation in Sludge 1 10 100 1000 10000 100000 InfluentEffluentDigested Sludge TCS TCC ppb < 1 ppb Accumulation Heidler and Halden (2004 Preliminary Estimate)

28. Fate of Biocides During Conventional Activated Sludge Wastewater Treatment TCS Mass in effluent Mass degraded TCC Mass in sludge 45% 1% 54% 3% 54% 43% Heidler and Halden (2004 Preliminary Estimate) (Data shown are based on a conservative 2004 estimate; revised estimates have been submitted for publication )

29. Estimated Mass & Use of Sludge in the U.S. Land Application 63% Landfills 17% Other 1% Incineration 19% Biosolids Applied to Land, National Research Council of the National Academies, 2002 Sludge: A Potential Resource: 12.5 Billion dry lb/yr After successful removal from wastewater, the majority of captured compounds is re- introduced into the environment

30. Biocides: Transfer from Water to Ag Soils Plant removes but does NOT degrade biocides effectively Biocides are transferred into municipal sludge Concentration ratio sludge/effluent: ~100,000 >150,000 lbs/yr of TCS and >175,000 lbs/yr of TCC are applied on agricultural land in sludge used as fertilizer Neither biocide is approved/tested for use in agriculture Heidler and Halden (2004 Preliminary Estimate)

31. Overview Background Primary exposures Secondary exposures –Biocides in aquatic environments –Biocides in terrestrial environments Biocides in food, drinking water, human milk, blood, and urine Summary

32. Are People Getting Unintentionally Exposed and What Are the Risks/Outcomes?

33. Rare Infant Deaths From Laundry Disinfectants AJPH 60(5):901 (1970)

34. 1967: Rare Deaths Due to Improper Use of Laundry Agents 1967, Booth Memorial Hospital, St. Louis, MO Infants: sweating, fever, difficulty breathing 2 deaths, multiple illnesses 2 drums of Loxene found in laundry closet –22.9% chlorophenols –4% triclocarban Analysis of blood showed phenol poisoning AJPH 60(5):901 (1970)

35. Methemoglobinemia in Infants: U.S. Pediatrics, February 1963 Committee on Drugs “...clinical judgment would dictate avoiding... even the most innocent-appearing substances in the nursery...until data on toxicity are available...” (verbiage from final paragraph) Pediatrics, December 1971

36. Human Exposure to Environmentally Persistent Biocides Triclosan in drinking water resources (Multiple reports) Triclocarban in fruit juice (Sapkota et al. unpublished) Triclosan in fish (Multiple reports) Triclosan in breast milk (1 Report published; 1 in preparation) Triclosan/Triclocarban in human blood (WWF; Sapkota et al. unpublished) Triclosan in human urine (CDC, 2005)

37. In Summary: The Biocides TCS and/or TCC... –persist in the environment –are produced faster than they degrade (unsustainable usage) –contaminate sludge, a potentially valuable resource –contaminate the food supply –bioaccumulate in biota (e.g., fish) –are detectable in human blood, milk and urine (general population) –contaminate soils and aquatic sediments; consequences unknown These known/potential risks need to be weight against potential benefits

38. Acknowledgments Daniel Paull, Jochen Heidler, Amir Sapkota, David Colquhoun, Rey de Castro Guy Hollyday (Baltimore Sanitary Sewer Oversight Coalition) John Martin and Nick Frankos from the Department of Public Works, City of Baltimore Triclocarban research was made possible by the –NIEHS grant P30ES03819 (Pilot Project) –JHU Faculty Innovation Award –CRF of Maryland –JHU Center for a Livable Future –JHU Faculty Research Initiative

39. Selected References 1.Kolpin et al., Environ. Sci. Technol., 36:1202, 2002 2.Halden and Paull, Environ. Sci. Technol., 38(18):4849, 2004 3.Halden and Paull, Environ. Sci. Technol., 39(6):1420, 2005 4.Okumura, Nishikawa, Anal. Chim. Acta, 325:175, 1996 5.Latch, J. Photochem. Photobiol., 158:63, 2003 6.Gledhill, Water Research, 9:649, 1975 7.Clark et al., Int. J. Environ. Anal. Chem., 45:169, 1991 8.Bester, Water Research, 37:3891, 2003 9.Federle et al., Environ. Toxicol. Chem., 21:1330, 2002 10.McAvoy et al., Environ. Toxicol. Chem., 21:1323, 2002 11.Heidler and Halden, ACS National Meeting, Washington, DC, 2004.

42. Monitoring at Other U.S. Treatment Plants Is Ongoing Population (1996 data) Heidler and Halden (unpublished)

43. TCC in River Sediments Source: Wastewater Treatment Plant

44. TCC in Human Urine 30 Anonymous Adult Volunteers Lacking Occupational Exposures 24 Had Detectable Levels of Triclosan Mean 127 ng/mL = µg/L = ppb 5th to 95th Percentile: <LOD to 702 ng/mL Ye et al. 2005 Anal. Chem. 77:5407-5413; Data from the CDC in Atlanta, GA

45. Ecological Risk Posed by 3,4-Dichloroaniline Versteeg et al. 1999; Environ. Tox. Chem. 18(6):1329