Supplemental information

Observed volatilization fluxes of S-metolachlor and Benoxacor applied on soil with and without crop residues

Bedos C.1*, Alletto L.2, Durand B.1, Fanucci O.1, Brut A.3, Bourdat-Deschamps M.1 , Giuliano S. 2, Loubet B. 1, Ceschia E.3, Benoit P.1

Number of pages: 4

Number of Tables: 4

Number of Figures: 4

-  Air sampling

Table S 1 Air sampling

Sample number / T-MM1 / Duration (min) / T-MM3 / Duration (min) / Plot / Duration (min)
D1S1 / 116.260 / 210 / 116.281 / 210 / 136.51 / 170
116.406 / 116.417 / 136.63
D1S2 / 116.417 / 210 / 116.427 / 210 / 136.63 / 144
116.552 / 116.563 / 136.73
D1S3 / 116.563 / 200 / 116.573 / 200 / -
116.698 / 116.708 / -
N1S4 / 116.719 / 795 / 116.719 / 795 / 136.73 / 777
117.271 / 117.271 / 137.27
D2S5 / 117.292 / 210 / 117.292 / 210 / 137.27 / 207
117.427 / 117.427 / 137.42
D2S6 / 117.448 / 210 / 117.448 / 210 / 137.42 / 205
117.583 / 117.583 / 137.56
D2S7 / 117.604 / 210 / 117.604 / 210 / 137.57 / 236
117.740 / 117.740 / 137.73
N2S8 / 117.760 / 735 / 117.760 / 735 / 137.73 / 777
118.260 / 118.260 / 138.27
D3S9 / 118.281 / 210 / 118.281 / 210 / 138.27 / 207
118.417 / 118.417 / 138.42
D3S10 / 118.438 / 210 / 118.438 / 210 / 138.43 / 198
118.573 / 118.573 / 138.56
D3S11 / 118.594 / 210 / 118.594 / 210 / 138.56 / 208
118.729 / 118.729 / 138.71

Table S 2 Chemical analysis

Splitless method / Split method
TDS3 / 30 to 325 °C (hold 8 min) at 60 °C/min in the TDS splitless mode / Same conditions with transfer step (transfer into the GC system) operated with split to analyze highly concentrated samples
Transfer line / 325 °C
Cooled injection system / -50 °C to 325 °C (hold 23 min) at 12 °C/s (straight glass liner) in the solvent vent mode
Helium flow rate / 200 mL/min
/ Compound / CAS number / Ion 1 / Ion 2 / Retention time (min) /
Benoxacor / 98730-04-2 / 120 / 259 / 15.0
Metolachlor / 51218-45-2 / 162 / 238 / 15.5

Table S 3 Calibration points for air, soil, and plant residue samples

Air sample analysis
Example n°1 / 0.1-0.2-0.5-1-5-25 ng
Example n°1 / 0.2-0.5-1-5-25-100 ng
Example n°1 / 1-5-25-100-200-500 ng
Example n°1 / 10-25-50-100-200 ng
Soil sample analysis / 0.01-0.035-0.07-0.15-0.25-0.375-1 µg/ml

-  Recovery tests for soil and crop residue extraction

Soil and crop residues samples were spiked before extraction with a mixture of s-metholachlor, OA and ESA. The concentrations of each compound were 100µg/kg and 150µg/kg for soil and crop residue, respectively, corresponding to a final concentration in the extract before analysis of 0.3µg/mL and 0.1µg/mL, respectively.

Table S 4 Recovery results for soil and crop residue samples

Soil / Crop residues
From Aslam et al. (2014) / This study / From Aslam et al. (2014)
rdt (%) / CV (%) / n / Rdt (%) / Rdt (%) / rdt (%) / CV (%) / n
Smeto / 104 / 4 / 5 / 105 / 100 / 76 / 30 / 3
OA / 57 / 3 / 5 / 30 / 38 / 35 / 8 / 3
ESA / 75 / 4 / 5 / 67 / 70 / 42 / 10 / 3

Figure S 1Picture of the three wind tunnels placed in the field. The arrow with thick dashed line represents the airflow direction inside the tunnel (left). Map of the field for the field scale experiment. The red point indicates the location of the different masts

Figure S 2 Latent heat of evaporation together with soil surface temperature for the wind-tunnel experiment

Figure S 3 Ratio of the concentrations in S-metolachlor and benoxacor in the air for each sampling periods (left) and in the applied solution, measured application dose with filters, air concentrations averaged over all sampling periods and cumulated fluxes (right)

Figure S 4 Cumulated volatilization fluxes of S-Metolachlor and Benoxacor for the wind-tunnel and field experiments