ENVIRONMENTAL MONITORING OF DIOXIN LIKE COMPOUNDS IN THE UNITED STATES

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ENVIRONMENTAL MONITORING OF DIOXIN LIKE COMPOUNDS
IN THE UNITED STATES

• Commission for Environmental Cooperation of North
  America
• Fourth Workshop on Sources and Measurements
• of Dioxins, Furans and Hexachlorobenzene
• October 28-29, 2010

Dwain Winters Winters Environmental Bethesda,
Maryland
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CRITICAL AREAS FOR ENVIRONMENTAL MONITORING

• DIOXIN IN LAKE SEDIMENT
• DIOXIN IN AMBIANT AIR
• DIOXIN IN SOIL

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LAKE SEDIMENT CORE INVENTORY
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TEMPORAL TRENDS IN SEDIMENT DIOXIN CONCENTRATION
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NATIONAL DIOXIN AIR MONITORING NETWORK(NDAMN)

• A nationally based ambient air monitoring network
  
• The target analytes are vapor and particulate
  phases of dioxin-like compounds
• 32 stations operated in rural and non-impacted
  sites
• Network started in 1999 and ended in 2004

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WHY WAS NDAMN CREATED?

• Establishing background levels
• Determining temporal and geographical
  variability
• Investigating long-range transport and
  transboundary movement
• Verify/calibrating EPAs air models
• Providing data to determine exposures
• \

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Measured Analytes
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(No Transcript)
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Dioxin Air Sampler
Quartz Fiber Filter for particle bound dioxin
PUF plug for vapor-phase dioxin
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Sampling Frame

• Sampling period
• 24 hrs/d 7 d/wk
• 28 days
• All stations operate simultaneously with 4
  sampling periods/year

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NDAMN Sampling Moments
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2000 NDAM Annual Average
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General increase observed in CDD/F TEQ in Late
Fall/ Early Winter vs Summer
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COMPARING 2001 RESULTS WITH POPULATION DENSITY
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General Observations for NDAMN from 1999 - 2001

• The dominant CDD/F congeners in ambient air were
  the OCDDgt1,2,3,4,6,7,8-HpCDDgt 1,2,3,4,6,7,8-HpCDFgt
  OCDF.
• This profile was constant over all NDAMN sites.
• The 1,2,3,7,8-PCDD contributes over 40 of the
  dioxin TEQ.

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General Observations for NDAMN from 1999 2001,
continued

• PCB-118 dominates coplanar PCBs in ambient air
  followed by PCB-105, PCB-77 and PCB-156.
• PCB-126 dominates the TEQ.

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NDAMN conclusions

• 22 rural sites
• Annual mean dioxin TEQ (WHO method) air
  concentrations
• Range 2 fg m3 to 28 fg/ m3
• Overall mean 12 fg m3.
• Mean annual PCB TEQ air concentrations
• Range 0.15 9 fg/ m3.
• Overall mean 1 fg/ m3.
• These values are consistent with other studies of
  rural areas.

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NDAMN CONCLUSIONS, continued

• 8 Remote Sites
• Annual mean dioxin TEQ (WHO method) air
  concentrations
• Range 0.5 to 3 fg/ m3
• Overall mean 1.05 fg/ m3
• Mean annual PCB TEQ air concentrations
• Range 0.05 1.0 fg/ m3
• Overall mean 0.23 fg/ m3

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NDAMN CONCLUSIONS, continued

• Dioxin concentrations at remote sites were on
  average one order of magnitude lower than what
  was measured at rural sites.
• Although not statistically significant, PCBs were
  approximately 5-times lower in remote sites as
  compared to rural sites.

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NDAMN CONCLUSIONS, continued

• CDDs and CDFs air concentrations have generally
  remained about the same from 1999 2001 when all
  NDAMN locations are considered.
• CDD and CDF air concentrations have decreased
  from 1999 to 2001 at a few specific locations.

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NATIONAL DIOXIN SOIL SURVEY
NDAMN air sampling stations. Circles indicate
stations included in soil survey and triangles
are excluded stations.
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Soil Survey Results
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HRMS CDD/CDF TEQs for all 27 sites.
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HRMS PCB TEQs for all 27 sites
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AIR COMPARED TO SOIL