Radionuclides in Ontario Drinking Water

Ontario Drinking Water

Licensed Testing of Radionuclides in Drinking Water

Maxxam is the only commercial laboratory licenced by the Ontario Ministry of the Environment for radionuclide analysis. We can provide determinations for the over 70 radionuclides listed in the Ontario Safe Drinking Water Act. We also do testing for other provinces and territories following Federal guidelines – click here for details.

MOE CERTIFICATE OF APPROVAL SAMPLES

Package Method Detection Limit
Radium-226
  • Alpha-Spectrometry
0.01 Bq/L
Tritium
  • Liquid Scintillation Counting
15 Bq/L
Gross Alpha, Gross Beta & Tritium
  • Gas Flow Proportional Counting
  • Liquid Scintillation Counting
0.1/0.1 Bq/L

15 Bq/L

Gross Alpha
Gross Beta
  • Gas Flow Proportional Counting
0.1/0.1 Bq/L

ONTARIO DRINKING WATER REGULATIONS

All water for human consumption in Ontario must be analyzed at a licenced laboratory (unless the water is federally regulated) and there is a surcharge for handling these samples.

Package Method Detection Limit
Radionuclide Screen for Gross Alpha, Gross Beta & Tritium
  • Gas Flow Proportional Counting
  • Liquid Scintillation Counting
0.1/0.1 Bq/L

15 Bq/L

Gross Alpha, Gross Beta
  • Gas Flow Proportional Counting
0.1/0.1 Bq/L

MOE Directive RE: Certified Labs for Drinking Water (PDF)

If screening levels are exceeded, Maxxam can provide recommendations for identification and quantification of the specific radionuclides.

Ontario Drinking Water Specific Determinations

Radionuclide Method Detection Limit
Radon-222 Gamma-Spectrometry 10 Bq/L
Radium-226 Alpha-Spectrometry 0.01 Bq/L
Tritium Liq. Scint. Counting 15 Bq/L
Lead-210 Beta-Counting 0.05 Bq/L
Polonium-210 Alpha-Spectrometry 0.01 Bq/L
Radium-224/226 Alpha-Spectrometry 0.01 Bq/L
Radium-228 Sep. + Gamma Spec 0.2 Bq/L
Strontium-90 Beta-Counting 0.2 Bq/L
Thorium Isotopes (Th-228,Th-230 & Th-232) Alpha-Spectrometry 0.01 Bq/L
Uranium Isotopes (U-234, U-235 & U-238) Alpha-Spectrometry 0.01 Bq/L
Th-232 Neutron Activation 0.01 Bq/L
U-238 Neutron Activation 0.01 Bq/L

Schedule 3 Ontario Drinking Water Standards

MACs (Maximum Acceptable Concentrations) of Radionuclides in Drinking Water *From Schedule 3: Radiological standards from Safe Drinking Water Act, 2002 – O. Reg. 169/03

Radiological Parameter Max in Bq/L Radiological Parameter Max in Bq/L
Natural Radionuclides
Beryllium-7 4000 Thorium-228 2
Bismuth -210 70 Thorium-230 0.4
Lead-210 0.1 Thorium-232 0.05
Polonium-210 0.2 Thorium-234 20
Radium-224 2 Uranium-234 4
Radium-226 0.6 Uranium-235 4
Radium-228 0.5 Uranium-238 4
Artificial Radionuclides
Americium-241 0.2 Niobium-95 200
Antimony-122 50 Phosphorus-32 50
Antimony-124 40 Plutonium-238 0.3
Antimony-125 100 Plutonium-239 0.2
Barium-140 40 Plutonium-240 0.2
Bromine-82 300 Plutonium-241 10
Calcium-45 200 Rhodium-105 300
Calcium-47 60 Rubidium-81 3000
Carbon-14 200 Rubidium-86 50
Cerium-141 100 Ruthenium-103 100
Cerium-144 20 Ruthenium-106 10
Cesium-131 2000 Selenium-75 70
Cesium-134 7 Silver-108m 70
Cesium-136 50 Silver-110m 50
Cesium-137 10 Silver-111 70
Chromium-51 3000 Sodium-22 50
Cobalt-57 40 Strontium-85 300
Cobalt-58 20 Strontium-89 40
Cobalt-60 2 Strontium-90 5
Gallium-67 500 Sulphur-35 500
Gold-198 90 Technetium-99 200
Indium-111 400 Technetium-99m 7000
Iodine-125 10 Tellurium-129m 40
Iodine-129 1 Tellurium-131m 40
Iodine-131 6 Tellurium-132 40
Iron-55 300 Thallium-201 2000
Iron-59 40 Tritium 7000
Manganese-54 200 Ytterbium-169 100
Mercury-197 400 Yttrium-90 30
Mercury-203 80 Yttrium-91 30
Molybdenum-99 70 Zinc-65 40
Neptunium-239 100 Zirconium-95 100

* Lower detection limits and all other drinking water radioisotopes are available, please inquire

Radionuclides in Ontario Drinking Water