Passive & High-Volume Atmospheric Samplers:A Comparison of Sampling Rates for Currently-Used Pesticides

Jason Slobodian, Don Waite & Tom HarnerEnvironment Canada, Science & Technology BranchAir Quality Research Division

Allan CessnaAgriculture and Agri-Food Canada, Research Branch Environmental Health

Ludo TuduriUniversité Bordeaux ILaboratoire de Physico-toxicochimie des systèmes naturels

Jim Sproull & Diana ChauEnvironment Canada, Science & Technology BranchPrairie and Northern Laboratory

Agriculture on the PrairiesArea Seeded to Major Crops 2005(Grains, Oilseed and Pulse Crops)

Saskatchewan14.30 Mha

52.5%

Manitoba 3.26 Mha

12.0%Other

Provinces 3.08 Mha

11.3%

Alberta 6.59 Mha

24.2%Sources:

Alberta Agriculture, Food and Rural Development

Saskatchewan Agriculture and Food

Manitoba Agriculture, Food and Rural Initiatives

Pesticide Use on the PrairiesEstimated Annual Usage

Pesticide RankQuantity Used

in Canada(kg)

% Used inAlberta &Manitoba

Glyphosate 1 4.61×106 69%

MCPA 3 1.54×106 87%

2,4-D 4 1.49×106 92%

Saskatchewan, the largest pesticide user is Canada with 36% of sales, is not included

Source: Brimble et al. 2005, Pesticide utilization in Canada: A compilation of current sales and use data

PrairiePrairie & Northern Canada Atmospheric Network (PANCAN)

Current-Use PesticidesPre-emergent Herbicides

EthalfluralinTrifluralin

Triallate

Current-Use PesticidesPost-emergent Herbicides

BromoxynilDicamba

2,4-DMCPA

Current-Use PesticidesAmerican Herbicides

Alachlor AtrazineMetolachlor

Lindane(γ-HCH)

Insecticide

High-Volume Sampling

High-Volume SamplingTriallate 2005

0.00

1.00

2.00

3.00

4.00

5.00

6.00

18-M

ay-05

25-M

ay-05

1-Jun

-058-J

un-05

15-Ju

n-05

22-Ju

n-05

29-Ju

n-05

6-Jul-

0513

-Jul-0

520

-Jul-0

527

-Jul-0

53-A

ug-05

Con

cent

ratio

n (n

g/m

3 )

Bratt's Lake 1 mBratt's Lake 10 mBratt's Lake 30 mHaffordWaskesiu

High-Volume SamplingBromoxynil 2005

0.00

1.00

2.00

3.00

4.00

5.00

6.00

18-M

ay-05

25-M

ay-05

1-Jun

-058-J

un-05

15-Ju

n-05

22-Ju

n-05

29-Ju

n-05

6-Jul-

0513

-Jul-0

520

-Jul-0

527

-Jul-0

53-A

ug-05

Con

cent

ratio

n (n

g/m

3 )

Bratt's Lake 1 mBratt's Lake 10 mBratt's Lake 30 mHaffordWaskesiu

Passive Sampling?

Passive Sampling

Passive SamplingAdsorption Curve

Time

Qua

ntity

on

PUF

Linear

Curvilinear Equilibrium Partitioning

Laboratory Analysis of Samples

• Analysis was conducted by Environment Canada’s Prairie and Northern Laboratory in Edmonton

• Samples were:– Treated with 2,4-D d5– Soxhlet extracted– Concentrated– Methylated with diazomethane– Analyzed by GC/MS/MS

• For high-volume samples, the glass fibre-filter and PUF/XAD2 cartridge were simultaneously analyzed

% Detection of Pesticides in Passive SamplesRelative to High-Volume Samples

where the atmospheric concentration > 0.05 ng/m3

ND ND ND

• Sampling Rates are required to determine atmospheric concentrations

Quantity on PUF (ng)

Time Deployed (d)

Sampling Rates for Passive Samplers

÷ Sampling Rate (m3/d) = Atmospheric Conc. (ng/m3)

2,4-D Sampling Rate - Calculated by Linear Regression

y = 16.97x - 0.087R2 = 0.9223

0.0

2.0

4.0

6.0

8.0

10.0

12.0

14.0

16.0

0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80

Hi-Vol Concentration (ng/m3)

Mas

s Sa

mpl

ing

Rat

e (n

g/d)

10 m30 m

Sampling Rate = 17 ± 2 m3/d

2,4-D Sampling RateBratt’s Lake Data 2003 - 2005

Triallate Sampling Rate - Calculated by Linear Regression

y = 12.646x + 0.4196R2 = 0.8627

0.0

10.0

20.0

30.0

40.0

50.0

60.0

70.0

80.0

90.0

0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00

Hi-Vol Concentration (ng/m3)

Mas

s Sa

mpl

ing

Rat

e (n

g/d)

10 m30 m

Sampling Rate = 13 ± 2 m3/d

Triallate Sampling RateBratt’s Lake Data 2003 - 2005

Trifluralin Sampling Rate - Calculated by Linear Regression

y = 1.2813x + 1.9684R2 = 0.0033

y = 8.1929xR2 =0.7345

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

9.0

10.0

0.00 0.10 0.20 0.30 0.40 0.50 0.60

Hi-Vol Concentration (ng/m3)

Mas

s Sa

mpl

ing

Rat

e (n

g/d)

10 m30 m

Trifluralin Sampling RateBratt’s Lake Data 2003 - 2005

Sampling Rates

Pesticide

Sampling Rate (ng/m3)

(±95% confidence interval)

Correlation Coefficient,

r

Ethalfluralin 10 ± 1 0.8395Trifluralin 8 ± 2 0.8570Triallate 13 ± 2 0.9288Bromoxynil 12 ± 1 0.8908Dicamba 18 ± 1 0.8725MCPA 14 ± 2 0.94482,4-D 17 ± 2 0.9604Lindane 10 ± 1 0.7608

Based on Data from 2003 - 2005

Determining Sampling Rates using Depuration Compounds

Time

Qua

ntity

on

PUF

Adsorption Curve

Depuration Curve

Depuration Compound Study 2005Comparison of passive sampling rates (m3/d) for lindane determined by: (1) deuterated depuration compound and

(2) hi-vol/passive calculation

(1) γ-HCH d6 (2) Hi-Vol/Passive13 1011 76 69 67 77 77 89 8

Average (S.D.) 9 ± 3 Average (S.D.) 8 ± 1

Minimum Detection Levels90 Day Deployment

PesticideLaboratory

Detection Limit(ng)

PassiveSampling Rate

(m3/d)

AtmosphericDetection Limit

(ng/m3)Ethalfluralin 50 10 0.06

Trifluralin 50 8 0.07

Triallate 50 13 0.04

Bromoxynil 50 12 0.05

Dicamba 50 18 0.03

MCPA 50 14 0.04

2,4-D 50 17 0.03

Lindane 10 10 0.01

Conclusions

• Passive samplers are a simple, cost-effective method for determining pesticides in the atmosphere.

• Further research is required to determine sampling rates for passive samplers.

Further Research

• Investigate whether physical-chemical properties of pesticides can be correlated with sampling rates (e.g. octanol/air partition coefficient).

• Conduct more extensive depuration study using 11 deuterated current-use pesticides.

• Perform a time series depuration study to determine the desorption curve.

Financial Support•Toxic Substances Research Initiative

•Pesticide Science Fund

Acknowledgements

Summer Students:• Kyle Galloway• Nathan Droneck• Mackenzie King

Bratt’s Lake Staff:• David Halliwell• Ormanda Niebergall

Technicians:• Dwight Quiring• Jon Bailey