The Government of Canada's updated approach to promoting chemical safety relies on laboratory testing to characterize substances before regulatory decisions are made. The test object covers regulated chemical substances and their residues in environmental and biological matrices. This article outlines the testing framework in a stepwise manner: the scope of testable elements, sample types and collection practice, chromatographic and mass spectrometric determination, assay sensitivity and linear range, co-test parameters, and acceptance criteria with reporting requirements. Together these modules describe how laboratories generate the analytical evidence used in screening assessments.
scope and testable elements
The scope of testing under this regulatory approach includes identification and quantification of chemical substances in various sample matrices. Testable elements fall into three groups: parent compounds, transformation products, and physicochemical properties that govern fate and transport. Parent compound analysis establishes concentration levels against reference values. Transformation product analysis addresses metabolites and degradation products formed in environmental or biological systems. Property testing covers parameters such as water solubility, partition behavior, volatility, and persistence indicators. Each element requires a defined analytical technique and a documented measurement objective. Laboratories select test items based on the screening question posed, the expected concentration range, and the matrix involved. The scope statement in the test plan should list target analytes, matrices, methods, and reporting units. Ambiguity in scope is a common cause of rejected data, so the plan must state which elements are quantitative, which are screening-level, and which require confirmation by a second technique.
Sample types and collection
Sample types under this framework span environmental, biological, and product categories. Environmental matrices include surface water, groundwater, sediment, soil, and air. Biological samples include tissues and fluids collected from organisms. Product samples include formulations and materials subject to notification requirements. Collection protocols follow standard chain-of-custody practice: containers must be chemically inert toward the target analytes, and preservation conditions such as refrigeration or pH adjustment must be specified before sampling begins. Field blanks, trip blanks, and duplicate samples are collected at a defined frequency to document contamination and variability during transport. Sample volumes are set according to the expected detection limit and the amount required for extraction and repeat analysis. Holding times between collection and analysis must be recorded, since many analytes degrade or adsorb to container walls beyond defined windows. All sampling records identify location, date, collector, and preservation method so results remain traceable.
Determination
by chromatography and mass spectrometry
Instrumental determination applies chromatographic separation coupled with mass spectrometric detection. Gas chromatography with mass spectrometry suits volatile and semi-volatile organic compounds after solvent extraction or headspace preparation. liquid chromatography with tandem mass spectrometry suits polar, thermolabile, and high-molecular-weight substances, typically following solid-phase extraction or dilute-and-shoot preparation. The chromatographic column is selected by analyte polarity; a polyethylene glycol polar capillary column (wax column) serves polar volatiles, while reversed-phase columns serve general liquid chromatography work. Mass spectrometric detection uses selected ion monitoring or multiple reaction monitoring to improve selectivity at low concentrations. Identification relies on retention time agreement with a calibration standard plus qualifying ion ratios within stated tolerances. Quantification uses an internal standard added before extraction to correct for losses. Tuning, calibration verification, and system suitability checks precede each analytical batch, and continuing calibration checks are run at defined intervals to confirm instrument stability.
Assay sensitivity and linear range
Sensitivity is expressed as the method detection limit and the limit of quantification, both established during validation. The detection limit reflects the lowest signal distinguishable from noise; the quantification limit reflects the lowest concentration measurable with acceptable precision and bias. Calibration establishes the linear range, typically verified with a multi-point curve bracketing expected sample concentrations. Linearity is judged by the correlation coefficient and by residual patterns across the curve, not by the coefficient alone. When samples exceed the upper calibration point, dilution and reanalysis are required rather than extrapolation. Matrix effects in mass spectrometric methods can suppress or enhance response, so validation includes matrix-matched calibration or standard addition where suppression is substantial. Reporting of non-detected results states the detection limit rather than zero, and results between the two limits are reported as detected but not quantifiable. These conventions keep sensitivity claims verifiable across laboratories.
Co-test parameters
A complete data package includes supporting measurements that give context to the primary results. For water samples, pH, conductivity, dissolved organic carbon, and suspended solids influence speciation and partitioning of the analyte. For soil and sediment, organic matter content, particle size distribution, and moisture content affect extraction recovery and comparability. For biological samples, lipid content and moisture normalize residue concentrations on a consistent basis. Quality control co-tests include method blanks, laboratory control samples, matrix spikes, and duplicates, each with defined acceptance windows. Recovery from matrix spikes indicates extraction efficiency, while duplicate precision reflects homogeneity of the sample. When co-test values fall outside expected ranges, the primary result may require qualification or reanalysis. Co-test data also support interpretation of trends across sites and sampling events, because concentration differences often track changes in these governing parameters rather than true changes in analyte levels.
Acceptance criteria and reporting
Acceptance criteria are fixed before analysis and applied without post-hoc adjustment. Typical criteria cover calibration linearity, continuing calibration verification within a stated percentage of the true value, method blank cleanliness, matrix spike recovery within defined bounds, and duplicate relative difference below a set limit. Results from a batch that fails a criterion are qualified, reanalyzed, or rejected according to the documented decision rule. The final report states the sample identity, collection details, analytical method, target analytes, results with units, detection limits, and quality control outcomes. Deviations from protocol are described with their effect on data usability. Uncertainty may be reported where the end use requires it. Signed reports follow chain-of-custody documentation so each value can be traced from collection to instrument record. This structure allows regulators to review submitted data against the stated criteria and reach defensible screening decisions.
Frequently Asked Questions
What
sample types does the Government of Canada's approach to promote cover, and how should they be collected?
The covered scope defines testable elements and specifies accepted sample types along with collection requirements. Submission must follow the stated sample handling conditions so that the tested material remains suitable for the chromatography and mass spectrometry determination described in the method.
How do I choose between methods under the Government of Canada's approach to promote, and when is each applicable?
Method selection depends on the testable elements within the defined scope. Chromatography coupled with mass spectrometry is used for determination, and applicability differences relate to assay sensitivity, the linear range, and co-test parameters, which should be matched to the sample type and the analytes being assessed.
On what basis are results judged under the Government of Canada's approach to promote, and which limits are referenced?
Judgment relies on the acceptance criteria and reporting requirements set out in the approach, supported by assay sensitivity and linear range performance. Reported outcomes reflect whether measured values fall within the defined acceptance criteria, with no additional limit references applied beyond those specified in the documentation.