BIOMARKERS OF CHEMICAL EXPOSURE AT AAMJIWNAANG. Nil Basu, PhD and Diana Cryderman, PhD University of Michigan School of Public Health

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1 BIOMARKERS OF CHEMICAL EXPOSURE AT AAMJIWNAANG Nil Basu, PhD and Diana Cryderman, PhD University of Michigan School of Public Health

2 ABOUT THIS REPORT: This study was co-conducted by researchers at the University of Michigan School of Public Health and the Environment Office (Sharilyn Johnston, Christine Rogers, Wilson Plain Jr.). We thank the study participants for their interest and time, and Chief Christopher Plain and Band Council members for their support. We also thank Dr. Fiona Miller, Dr. Stuart Batterman, Dr. Sergei Chernyak, Dr. Don Patterson, Dr. Amy Schulz, Dr. Howard Hu, Lisa Letourneau, Mozhgon Rajaee, Jessica Barno, Caitlyn Kowalsky and Lawrence Kowalsky for technical assistance. Funding for this study was received from the University of Michigan Rackham Graduate Program, the U.S. NIEHS Environmental Toxicology Research Training Grant (T32 ES07062), the Great Lakes Commission s GLAD program, the Michigan Institute of Clinical Health Research s CTSA program (UL1RR024986), and the University of Michigan School of Public Health. SUGGESTED CITATION: Note, this report will be submitted for scientific peer-review in late The suggested citation is: Basu, N., Cryderman, D.K., Miller, F.K., Johnston, S., Rogers, C., Plain, W Multiple Chemical Exposure Assessment at. McGill Environmental Health Sciences Lab Occasional Report

3 We are losing our people, losing our history. Our environment is affecting all life, not just humans member, Lambton County Health Study Open House SUMMARY A number of environmental pollutants were measured in biomarker samples from 43 motherchild pairs living in the region Pollutants measured included various metals, polycyclic aromatic hydrocarbons (PAH), perfluorinated chemicals (PFC), brominated flame retardants (BFR), polychlorinated biphenyls (PCB), and organochlorine pesticides (OCP) Potential sources of these chemicals are industries, the general environment and home Despite some limitations of our study, the findings show that mothers and children in the region are exposed to a number of environmental pollutants Some exposures trended higher than the average Canadian; notable chemicals include cadmium, possibly mercury, some perfluorinated chemicals (PFCs), some polychlorinated biphenyls (PCBs), hexachlorohexane (HCH), and DDT Based on these findings, recommendations are offered at the end of the report. 2

4 INTRODUCTION The First Nation, previously known as the Chippewas of Sarnia, is an Ojibwe Tribe situated in the heart of the Great Lakes Basin. The Reservation lands are located near the Canadian city of Sarnia (Ontario) and American city of Port Huron (Michigan). is a community of 850 members. An additional 100,000 people reside in neighboring St. Clair County (Michigan) and Lambton is highlighted in red. Dots refer to reporting industries County (Ontario). Simply put, is surrounded by pollution. The region is known as Chemical Valley. More than 50 multi-national industrial facilities are found within a 25 km radius of lands. The industrial facilities surrounding are primarily involved in the petrochemical, polymer, and chemical manufacturing sectors. In 2009 these facilities collectively released more than 110 million kilograms of pollution into the air. About 60% of these releases occurred within 5 km of. The released chemicals are complex mixtures of metals (e.g., mercury, lead, cadmium, manganese, aluminum), volatile and persistent organics (e.g., benzene, polycyclic aromatic hydrocarbons), and dust and particulate matter. Emerging chemicals of concern (e.g., brominated flame retardants, perfluorinated chemicals) also exist in the region. All these chemicals are potent neurotoxicants, carcinogens, and/or endocrine disruptors. PURPOSE Despite a strong belief that chronic exposures to toxic chemicals is impacting health and causing persistent uneasiness at, and in the surrounding region, little is known about direct human exposures. As such, the current community-based study was conducted to assess exposures to various chemical pollutants. A scientific biomarker approach was taken, meaning that chemical pollutants were analytically measured in blood, urine, and hair samples from participating individuals. 3

5 RECRUITMENT & SAMPLING Band Council Resolution (BCR 2008/ ) was obtained University of Michigan Institutional Review Board (IRB: HUM ) approved human subjects work Recruitment was performed via multiple methods, including word-of-mouth, flyers, mailings, and newspaper ads 42 mother-child pairs were recruited from the First Nation Reserve and surrounding areas; children were 4-14 years old Prior to participating each mother (or guardian) provided consent for herself and her child, and children provided assent to participate Blood was collected by a licensed phlebotomist (Lifelabs) via venipuncture Urine was collected into plastic vessels Detailed surveys were conducted but are not reported upon here LAB ANALYSES Metals (9 chemicals) in blood and urine were measured via ICPMS and DMA Perfluorinated chemicals, PFCs, (13 chemicals) in serum were measured by HPLC-MS Polychlorinated biphenyls, PCBs, (81 chemicals) in whole blood Polycyclic aromatic hydrocarbons, PAHs, (15 chemicals) in whole blood Organochlorine pesticides, OCPs, (21 chemicals) in whole blood Brominated flame retardants, BFRs, (22 chemicals) in whole blood All chemicals were measured analytically at the University of Michigan School of Public Health except for the PFCs which were measured by AXYS Analytical (Sydney, BC) Not all chemicals were detected, and here we only report upon those measured All concentration units are µg/l (part per billion), unless otherwise indicated Many quality control (QC) steps were taken but not reported here Results are compared to biomonitoring data from Canada (Canadian Health Measures Survey ) and the U.S. (4th NHANES Biomonitoring Survey) Results are presented as 50th and 90th percentile values <LOD means below detection limits 4

6 MERCURY A naturally occurring element that exists in a number of forms and is used in a number of industrial applications. There exists a rich history of mercury use in the region. HOW MIGHT PEOPLE BE EXPOSED? Organic mercury (OHg) is mainly found in fish, and thus consumed Inorganic mercury (IHg) is found in dental amalgam and can also be released by some industries; can be inhaled or consumed Mercury exists in the region (detected in air, water, sediment, soil, fish) Mercury RESULTS - CHILDREN Hair Hg Blood Hg Urine Hg <LOD 1.02 Mercury RESULTS - MOTHERS Hair Hg Blood Hg Urine Hg BOTTOM LINE? Organic mercury exposure (hair and blood) is within the reference range, and possibly reflects limited fish consumption by the community Inorganic mercury exposure (urine) is within the expected range Some individuals tend to have higher exposures 1 Hair Hg values are in ug/g; urine and blood are in ug/l 5

7 OTHER METALS Naturally occurring elements with varied chemical and physical properties that make them useful in our society. Many domestic, commercial & industrial sources exist. HOW MIGHT PEOPLE BE EXPOSED? Inhalation and ingestion are most likely routes of exposure Metals exist in the region (air, water, sediment, soil, fish) RESULTS 1 - CHILDREN Antimony Arsenic Cadmium Copper ,139.7 Lead Manganese Molybdenum Vanadium <LOD <LOD RESULTS 1 - MOTHERS Antimony Arsenic Cadmium Copper ,419.1 Lead Manganese Molybdenum Vanadium <LOD <LOD BOTTOM LINE? Exposures to most metals are not different than reference values Some metals (cadmium, vanadium) are slightly higher 1 Copper, Lead, and Manganese were measured in whole blood and all other elements were measured in urine 6

8 PCBS Manmade chemicals largely banned but still persist in the environment. Previously used in a number of industrial applications, such as coolants in transformers and motors. HOW MIGHT PEOPLE BE EXPOSED? Industries & old electrical items may leak PCBs into air, water, soil Some foods (fish, meat, dairy) may be contaminated PCBs exist in the region (sediment, fish) RESULTS - CHILDREN PCB <LOD 0.0 PCB PCB PCB PCB RESULTS - MOTHERS PCB PCB PCB PCB PCB BOTTOM LINE? PCB exposures are elevated in mothers and children, but sources and exposure routes are not clear Children have higher levels due to unique susceptibilities, such as handto-mouth contact and immature metabolic (or detoxification) pathways 7

9 PERFLUOROCHEMICALS (PFC) Useful manmade chemicals because they repel oil, water, and grease. Used mainly as surface protectors (e.g., carpet, clothes, paper) and also in fire-fighting foams. HOW MIGHT PEOPLE BE EXPOSED? These chemicals persist in the environment and do not breakdown easily Main exposure routes are eating, drinking, or breathing contaminated sources (e.g., dust, carpets, fire-fighting foams) RESULTS - CHILDREN PFOA PFNA PFDA PFHxS PFOS RESULTS - MOTHERS PFOA PFNA PFDA PFHxS PFOS BOTTOM LINE? Exposures exist, particularly in children More studies should be conducted to pinpoint the source and exposure routes (i.e., are they from industrial, commercial, or domestic sources?) 8

10 BROMINATED FLAME RETARDANTS These are manmade flame retardant chemicals added to a wide number of products (such as electronics and furniture) to make them difficult to burn. HOW MIGHT PEOPLE BE EXPOSED? These chemicals persist in the environment and do not breakdown easily Main exposure routes are eating, drinking, or breathing contaminated sources (e.g., dust, carpets) RESULTS - CHILDREN BDE BDE BDE BDE BDE <LOD <LOD RESULTS - MOTHERS BDE BDE <LOD 7.5 BDE <LOD 9.1 BDE <LOD 14.5 BDE <LOD <LOD BOTTOM LINE? There is evidence of some human exposures in the region, but levels are relatively low 9

11 POLYAROMATIC HYDROCARBONS PAHs are 100+ different chemicals that are formed during the incomplete burning of coal, oil, gas, garbage, meats, and other organic matter. HOW MIGHT PEOPLE BE EXPOSED? Breathing air with PAHs (e.g., some industries, vehicles, cigarettes) Eating certain foods that are grilled or charred PAH RESULTS CHILDREN AND MOTHERS CHILDREN MOTHERS Napthalene Acenapthene Phenanthrene Anthracene Fluoranthene Pyrene BOTTOM LINE? There is evidence of human exposures in the region, but there is no appropriate reference study for comparison Given the number of likely PAH sources in the region, more studies are needed with biomarkers (e.g., serum, urine) and field sampling 10

12 ORGANOCHLORINE PESTICIDES Manmade chemicals used largely throughout the 20 th century as insecticides. Many are now banned, but they breakdown slowly and thus still persist in the environment. HOW MIGHT PEOPLE BE EXPOSED? These chemicals persist in the environment and do not breakdown easily Main exposure routes are eating, drinking, or breathing contaminated sources (e.g., certain foods, proximity to landfills and waste sites) OCP RESULTS - CHILDREN HCB HCH <LOD <LOD DDE DDT <LOD <LOD OCP RESULTS - MOTHERS HCB HCH DDE DDT <LOD <LOD BOTTOM LINE? DDT and HCH exposures seem elevated More studies should be conducted to pinpoint the source and exposure routes, especially since these chemicals are largely banned 11

13 LIMITATIONS Recruitment was challenging and prone to sampling bias as individuals volunteered themselves for participation A cross-sectional study that only provides a snapshot in time and thus may not be representative of other times (e.g., susceptible life-stages, seasonality in exposures, certain industrial activities or releases) No ideal reference population was available for comparison (as available, data were compared to Canadian and U.S. Biomonitoring programs) More than 150 pollutants were analyzed here but many other chemicals exist in the region that need further study (e.g., benzene) Despite being the first biomonitoring study in the region, the resulting sample size was low and there is a need for a larger, more comprehensive study that integrates exposures with health outcomes CONCLUSIONS Despite some limitations, the findings show that mothers and children in the region are exposed to a number of environmental pollutants Some of these pollutants may come from industry and others may come from the environment or home Exposures may be higher than the average Canadian for some chemicals such as cadmium, mercury, some PFCs, some PCBs, and some OCPs 12

14 RECOMMENDATIONS There is a need for a rigorous epidemiological study to comprehensively assess and characterize pollutant exposures and potential human health effects in relation to the various sources in the region (including broader Lambton County). Such a study should build upon the current report and be focused on both occupational and environmental exposures. In particular, it should consider children s exposure and health. There is a need for an enhanced and expanded ecological research study to monitor environmental quality on spatial and temporal scales. Such a study should include several monitoring sites (more than currently being tracked by various organizations), each site should be monitored regularly (several times per year) and over many years, and monitoring sites should include both ecological sites as well as human communities. Such a study would better help resolve pertinent source-fate-exposure pathways. There is a need to support an independent oversight panel that may provide objective and expert guidance concerning environmental public health risks in the region in relation to pollutant exposures. RESOURCES FOR MORE INFORMATION Aamjiwaang Environment: Study website: Agency for Toxic Substances & Disease Registry s (ATSDR) ToxFAQ TM to find out more information on the individual contaminants reported upon here: 13