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Environmental Article

New Reference Mix of Canadian Drinking Water Volatiles

By Jason Thomas, Environmental Innovations Chemist

  • New, complete mix includes 19 volatiles on Canadian Drinking Water List.
  • Simple purge and trap GC/MS analysis.
  • Rtx®-VMS column provides sharp peaks for early eluters, resolves heavier compounds.

Much like the US Environmental Protection Agency’s regulation of environmental contaminants in drinking water through the Safe Drinking Water Act, Canada has its own stipulations regarding drinking water. These mandates are laid out in the Guidelines for Canadian Drinking Water Quality published by Health Canada’s Water Quality and Health Bureau. Regulation falls under the jurisdiction of the individual provinces and territories, which use these guidelines to establish water quality requirements for municipal water sources.(1)

Here, we illustrate the analysis of the volatiles portion of the Canadian contaminants list, now available from Restek as Canadian Drinking Water Volatiles Mix (cat.# 30610). We analyzed a 25mL water sample containing 50ppb each analyte, using an OI Analytical 4660 purge and trap system, with autosampler, and an HP 5890/5971 GC/MS system. A 30m x 0.25mm ID x 1.4µm Rtx®-VMS column (cat.# 19915), in conjunction with a Siltek® deactivated 1mm ID split inlet liner and a 35:1 split, affords good peak shape for the early-eluting components, as well as good resolution for the heavier compounds. The Rtx®-VMS column is an excellent choice for many other volatiles applications as well.

Figure 1  Canadian Drinking Water Volatiles Mix analyzed on an Rtx®-VMS column.

  1. 1,1-dichloroethene
  2. methylene chloride
  3. chloroform
  4. carbon tetrachloride
  5. benzene
  6. 1,2-dichloroethane
  7. trichloroethylene
  8. bromodichloromethane
  9. toluene
  10. tetrachloroethylene
  1. dibromochloromethane
  2. chlorobenzene
  3. ethylbenzene
  4. m-xylene
  5. p-xylene
  6. o-xylene
  7. bromoform
  8. 1,4-dichlorobenzene
  9. 1,2-dichlorobenzene
Column:
Rtx®:-VMS 30m, 0.25mm ID, 1.4µm (cat.# 19915)
Sample:
50 ppb each analyte in 25mL water, prepared from Canadian Drinking Water Volatiles Mix (cat.# 30610), 2000µg/mL each component in purge & trap methanol
Inj.:
split, 35:1, 1mm ID Siltek® splitless inlet liner (cat.# 20972-214.1)
Inj. temp.:
200°C
Carrier gas:
helium
Linear velocity:
30cm/sec. @ 35°C, constant pressure
Oven temp.:
35°C (5 min.), to 70°C @ 5°C/min., to 220°C @ 20°C/min. (hold 3 min.)
Det.:
MS
Transfer line temp.:
150°C
Scan range:
35-250 amu
Ionization:
EI
Mode:
scan
Purge and Trap Conditions
Instrument:
OI 4660 Eclipse Purge and Trap
Trap:
#10 (Tenax®/silica gel/carbon molecular sieve)
Sample temp.:
40°C
Purge:
11 min. @ 40mL/min.
Desorb preheat:
185°C
Desorb:
0.5 min. @ 190°C
Desorb flow rate:
35.0mL/min.
Bake:
6 min. @ 210°C
Interface:
split injector
Transfer line temp.:
150°C

References

  1. www.hc-sc.gc.ca/ewh-semt/water-eau/drink-potab/index_e.html