Hudson Bay Mining and Smelting Co., Limited (HBMS) has operated a - - PowerPoint PPT Presentation

Hudson Bay Mining and Smelting Co., Limited (HBMS) has operated a fully-functional mine and base metal smelting complex in Flin Flon, Manitoba, since the 1930’s. Mining and smelting activities have gradually led to a build-up of naturally occurring metals in the environment in the Flin Flon area

• Historical releases related to wind

blown materials (fugitive dusts from tailings; storage piles) into residential communities or ecological areas of interest;

• Atmospheric emissions from

historical and/or on-going stack emissions from smelting facilities;

• Historical materials use off site (in

community or residential areas)

The ‘Flin Flon area’ includes Flin Flon and Channing, Manitoba, and, Flin Flon and Creighton, Saskatchewan

• 2007 Manitoba Conservation report;

“Concentrations of Metals and Other Elements in Surface Soils of Flin Flon, Manitoba and Creighton, Saskatchewan, 2006”

• Levels of some metals were elevated in soil but

there was no immediate risk to human health

• The report recommended further study to better

understand potential health risks for people living in the Flin Flon area related to the HBMS smelter emissions

• The Flin Flon Soils Study was the result of this

recommendation.

Scientific Peer Review Study Team Intrinsik Goss Gilroy Habitat HBMS Technical Advisory Committee Community Advisory Committee Community Independent Expert Review Panel Ethics Review

• Manitoba Conservation
• Manitoba Health
• Manitoba Innovation, Energy and Mines (IEM)
• Saskatchewan Ministry of Environment
• Saskatchewan Ministry of Health
• Health Canada
• Representatives from the Community

Advisory Committee (consists interested members of the public, including representatives of local organizations)

Establishment

• f Process

Technical Oversight/Government Interaction Supplemental Data Collection and QAQC Community Interaction Development of TOR and Study Protocol HHRA/ERA Weight of Evidence Evaluation External Review DRAFT REPORT FINAL REPORT

• RA is one of the tools in the “tool box”
• RA will inform the need for other tools, and will

provide direction

• Weight of evidence tools:
• Bioaccessibility
• Evaluation of

Exposure (biomonitoring)

• Medical Surveillance

(community health status)

• Human health risk assessment is a scientific process that

is used to estimate the likelihood that a population may experience adverse health effects as a result from exposure to particular chemicals in the environment.

• It considers the following factors:

– How dangerous a chemical is known to be; – How sensitive people are to the chemical; – How a person might come into contact with the chemical such as swallowing, breathing, or skin contact as well how often and how long they are exposed; and, – How much of the chemical a person is exposed to.

Summary of HHRA Results for Non-Cancer Endpoints (Toddler) Chemical East Flin Flon West Flin Flon Creighton Channing Typical Background Arsenic      Cadmium      Copper      Lead      Inorganic mercury      Methyl mercury      Selenium      Summary of HHRA Results for Carcinogenic Endpoints (Lifetime Receptor) Chemical East Flin Flon West Flin Flon Creighton Channing Arsenic     Cadmium    

 Negligible risk – no further investigation required  Potential risk – risk management or further consideration such as an Exposure Study of residents may be required

• An HHRA may indicate that further information is required

to understand exposure and potential human health risks

• A direct way to obtain additional information on human

health risks is to assess human exposure through biological samples (e.g. blood, urine)

• Biomonitoring or an evaluation of environmental

contaminant exposure can be undertaken to assist in supplementing the information in the HHRA

• An evaluation of exposure examines the levels of internal

exposure to selected chemicals that a person or group of people encounter

• Sometimes referred to as biomonitoring, these studies

focus on quantifying and determining exposures and effects in humans through the use of biomarkers – Biomarkers for measuring exposure are generally measurements of chemicals or chemical components that are found in people’s fluids or tissues (e.g. lead in blood, arsenic in urine, etc.)

• Evaluations of exposure provide information on actual

exposures received by people and account for exposures from all potential sources, pathways and routes that a person encounters

• What is the current level of internal exposure to chemicals of

concern in the population residing in the affected area?

• Do residents have higher levels of exposure than residents

living in areas without a point source of contamination?

• Based upon the current scientific literature, what are the health

risks from the levels of chemicals of concern in blood or urine found in people in the affected area?

• What personal factors are associated with the level of measured

internal exposure of people in the affected area (e.g., place of residence, place of work, level of chemicals in soil, age, gender, diet, personal habits, etc.)?

• Children, in general, are more sensitive to exposure to

environmental contaminants than adults.

• Children eat more food, drink more water, and breathe more air

relative to their size than adults do. So they may be exposed to relatively higher amounts of contaminants in these media.

• Behavior and habits are also a factor. Children’s normal

activities, such as putting hands in their mouths or playing on the ground, create additional opportunities for exposures to environmental contaminants that adults do not face.

• Environmental contaminants may affect children

disproportionately because their immune defenses are not fully developed or their growing organs are more easily harmed.

• In short, if the average exposure levels in children are not

elevated, it would be unlikely for other age groups to have elevated levels from just living in an exposed community (and not through their occupation).

• Preliminary info from the HHRA for the Flin Flon area indicated

that further information would assist to fully understand exposure to potential human health risks associated with some metals in the community

• Through September and October 2009 the study team

conducted interviews with 251 households

• Data was collected from 447 individuals
• 377 urine samples, 202 blood samples
• Urine was analyzed for arsenic (inorganic, and total) and

inorganic mercury

• Blood was analyzed for lead

10 20 30 40 50 60 70 80 90 100 East Flin Flon West Flin Flon Channing Creighton

Arsenic –soil (ug/g)

Arsenic

Results of the Urinary Arsenic Evaluation

• Urinary arsenic levels in Flin Flon are comparable to

levels in other communities (smelter and control)

• In general, total and inorganic urinary arsenic levels

found in children in the Flin Flon area were not high enough to be associated with increased health risks; a few children were referred for individual follow-up

• No real pattern relating elevated soil levels and

elevated exposures

20 40 60 80 100 120 140 East Flin Flon West Flin Flon Channing Creighton

Mercury – soil (ug/g)

Mercury

Results of the Urinary Inorganic Mercury Evaluation

• Urinary mercury (inorganic) levels in Flin Flon are less than in
• ther communities
• Majority of samples collected from Flin Flon had no detectable

levels of inorganic mercury

• Detectable levels were not high enough to be associated with

health risks

• No real geographic pattern of elevated exposure

50 100 150 200 250 300 350 400 East Flin Flon West Flin Flon Channing Creighton

Lead - soil (ug/g)

Lead

Results of the Blood Lead Evaluation

• Exposure study suggest that lead levels are slightly higher than

levels from national studies of similar age groups, and are similar to levels found in children in other atypically exposed Canadian communities

• Community averages are less than the current benchmarks;

however, benchmarks are trending lower and 13% exceed study benchmark (5 ug/dL)

• Several factors were identified as being potentially associated to

blood lead levels, including: – Child’s sex (males higher BLL than females) – Region of residence – Adult use of tobacco (number of current smokers in the house increases BLL) – Age of the house (potential indicator of lead paint) – Types of pipes

• Arsenic and Mercury

– No indication of elevated exposures – No further action warranted

• Lead

– Slightly elevated lead exposures were noted in West Flin Flon; to a lesser extent in Creighton and East Flin Flon – Source of lead is unclear; potential sources include

• Soil
• Plumbing
• Historic use of lead paint
• Lead-contaminated toys and consumer products
• Hobby items

– Based on the outcome of the HHRA and exposure studies, recommendations have been made to address lead in the environment

• Implementation of a hand washing campaign
• Lead–based paint information package

and test kits

• Instructional seminars on avoiding

exposure to lead paint during renovations

– Free equipment rental for home renovators (e.g., vacuums with HEPA filters)

• Information fact sheets describing ways to

reduce exposure to lead in drinking water (i.e., flush water from taps before use) and wild game (i.e., removing lead shot from meat)

• Follow-up blood lead study in fall of 2012 to

gauge effectiveness of risk management plan