Study of Environmental
Contamination of a Mining
and Smelting Town in Peru
Presentation
* St. Louisto:
St. Louis Section AIHA
February 17, 2006
By:
David A. Sterling, Ph.D., CIH
Fernando Serrano, MS
La Oroya *
Angela Hobsen, MPH
Saint Louis University School
of Public Health
International collaboration of an environmental exposure
study in La Oroya, Peru & the surrounding Mantaro River
Valley to assess biological & environmental contamination
levels from a local metal mine & smelters
Acknowledgements
Saint Louis University
School of Public Health
Chris King
R Greg Evans
Volunteers
Chris Reid
Mayan
Gale Carlson
Ryan Sterling (4)
CDC (Inorganic
Toxicology Lab)
NIOSH
ARZOBISPADO
DE HUANCAYO
Peru
Archdiocese of
Huancayo
Joining Hands Network
(Consortium of NGOs)
Other
International Peace
Observers (Columbus,
OH)
Niton (now part of
Thermo Electron Corp)
Environmetrics (now
part of PDC
Laboratories)
3
History Doe Run, La Oroya Peru
La Oroya metallurgic complex was built in the 1920's
by a U.S. company and was known as Cerro de Pasco
Copper.
1974 - Nationalized by the Peruvian government.
Became part of the Centromin mining organization.
1997 - Sold to Doe Run as part of Peru's privatization
of industry policy
Initial Studies
Blood Lead Study in a Selected Population from
La Oroya, released 1999 by the Director
General of Environmental Health (DIGESA) of
the Peruvian Ministry of Health. Only .9% of
children BlPb<10
Study of Blood Lead Levels of the People of La
Oroya by DRP 2000-2001 and in 2003 by
CooperAccion: Only .9% of children BlPb<10
2002 Report by Interamerican Association
for Environmental Defense & the Peruvian
Society of Environmental Law
>10ugPb/dl in 99% of children tested
Interior Dust Lead Levels in La Oroya, Peru,
2004 Asociacion Civil Labor and Cooperaccion,
Peru and Occupational Knowledge International,
CA USA. 88% exceeded 40ug/ft2, 100% in
Antigua
5
Main Research Questions
1.
What are the environmental levels of heavy
metals in La Oroya and Concepcion (the control
community)?
2. What are the biological (blood and urine) levels
of heavy metals?
3. Is there a difference between the two
communities?
4. What are the associations and factors between
exposure, behaviors and biological measures?
Oroya Antigua
Smelter
Oroya
Nueva
Cuipata
Study Design and Preparation
Minimum Statistical sample size AND reality of
time frame (For power of .8 to see a difference at =.05 for in blood
lead of 8ug/dL: N= 250 subjects distributed by age group and city.
Using prior information from both La Oroya and Hurculaneum, MO)
Approvals
SLU Institutional Review Board (IRB)
Peru Ministry of Health
Provincial Minister of Health
USDA Permit to import soil
CDC letter to import blood/urine
Getting to know the lay of the land, culture and
life style (i.e. how and what to measure?)
8
Methodology
Team Work and International Cooperation
International team of 80
8 Field Teams
2 Recruiters
1 Health Interviewer
1 Doctor
1 Medical Technician
1-2 Environmental Scientists (SLU)
1 International Peace Observer
Others:
Logistics, Planning, Transportation, Security and
Administrative
9
Methods
Population/Location Sample Selection
Stratified Random Sampling
Random selection of city area/blocks
Random selection of starting house
Up to one subject per age group per house
0-6, 7-12, 13-18, >18
Inclusion Criteria
Spanish speaking
Live in city for 3 years
Live in home for 3 months
10
Methods
Sampling Instruments and Media
Biological Sampling (For Metals)
Blood & urine samples
Questionnaire
Health behaviors and beliefs, demographics,
occupation, other exposures, .
Environmental Sampling (For Metals)
Dust Wipes (Floor/entry/bedroom, Food prep table,
Child hands) Modified HUD protocol
Soil First 2-4cm core
Residential Water - Rinse 2x, 50ml collection
Mantaro River (metals and biological indicators)
Paint
11
Analysis Of Samples
Blood (4) and Urine (13) ICP/DRC/MS (CDC)
Water (26) ICP EPA Method 200.7
(Environmetrix)
Dust and Soil (26) (XRF)
(SLU and NIOSH)
Soil - dried, ground and seived
to 125um
Wipes Niton protocol
Paint XRF for lead
12
Results
184 Homes Visited
367 Participants (Barely expected 250)
La Oroya 172 + 50 at office
Concepcion 145
Blood 364 samples
Urine 344 samples
Dust Wipes 715
Soil 92
Water 143 community, 13*3 Mantaro River
13
Results Reported Here
Aggregated results of blood and urine only
reported on initial 250 samples (IRB)
Initial results of dustwipe samples
14
Blood Lead ug/dL
Pre and Post Blood Lead
5
4.5
4
3.5
3
2.5
2
1.5
1
0.5
0
Ref Range*1.4 4.4
Pre
Post
Environmental Team Members
*50th to 95th %ile From the Third National Report on Human Exposure to Environmental Chemicals www.cdc.gov/exposurereport 15
Blood Mercury (ug/L)
Pre and Post Blood Mercury
9
8
7
6
Ref Range 0.3 1.9
Pre
5
4
Post
3
2
1
0
1
Environmental Team Members
50th to 95th %ile From the Third National Report on Human Exposure to Environmental Chemicals www.cdc.gov/exposurereport 16
17
18
19
20
21
22
23
Mean ug/sqft
Initial Dust Wipe Mean Loading For
La Oroya (LO) and Concepcion (C)
450
400
350
300
250
Inside Floor
Inside Food Prep
Outside
Handwipes 6M-6Y
Handwipes 7112Y
200
150
100
50
0
LO
C
Lead
LO
Arsenic
LO
Cadmium
24
Conclusions
Exposures to heavy metals (Pb, Cd, Cu,
As, Hg and others) are occurring in the
Mantaro River Valley (La Oroya and
Concepcion)
Exposures in La Oroya are generally
higher than Concepcion ~100 Km distant
Exposures in La Oroya Antigua are
higher than other areas of La Oroya
25
Whats Next?
Dealing with Ethical and Communication Issues in Community
Based Participatory Research
Translation and Dissemination
4 Public Meetings in December on first results
Final report to be presented in July
Additional Health Risk Communication
Participants informed about their individual results February
Education/counseling at community, family and individual levels
Radio campaigns, public meetings, fact sheets,
Control methods recommended individual, community, regional
Additional control methods being assessed
Further Evaluation of River Valley Impact From Mining and
Processing Activities?
26
Questions ???
27
