Contamination Investigation: Identification and Source Analysis

Have you found an unknown particle, an unusual deposit or an unwanted substance in your product, water or process? BJL Laboratoires assesses contamination investigation requests to characterise contaminants and investigate their possible sources.

The investigation combines a review of the circumstances, targeted analyses and, where possible, comparison with control samples. The objective is to provide useful data to understand the incident and guide corrective actions.

Have You Identified a Contamination Problem?

Describe the problem, the material involved and the circumstances of its discovery. Photographs and a comparison sample can help define the investigation.

Request a Contamination Investigation

What Is a Contamination Investigation?

A contamination investigation aims to characterise unwanted material found in a sample and examine possible explanations for its presence.

It can address several questions:

what is the nature of the contaminant?
does it consist of particles, metals or organic compounds?
does the contamination affect a single sample or several batches?
are there similarities with a raw material, equipment component or known deposit?
at which stage of the process does the contamination appear to arise?
which checks could help assess the effectiveness of a corrective action?

The analytical programme depends on the sample matrix, the quantity available and the information required. It is defined individually for each investigation.

When Should You Contact the Laboratory?

appearance of particles or foreign matter in a product;
presence of a deposit on a surface or equipment;
suspected contamination of water or an effluent;
an unusual increase in metal or pollutant concentrations;
differences between a routinely used raw material and a new batch;
contamination following maintenance or cleaning;
presence of residues at a particular process stage;
suspected cross-contamination between operations;
recurrence of a defect despite an initial corrective action.

Which Contaminants Can Be Investigated?

Particles, Dust, Deposits and Inclusions

Microscopic examination can provide information about particle shape, dimensions and appearance. Elemental microanalysis can supplement these observations to investigate composition.

BJL Laboratoires can assess the suitability of transmission electron microscopy combined with EDX microanalysis, depending on the sample and the preparation it allows.

Learn more about particle identification by TEM-EDX.

Metals and Elements

Elemental contamination can be investigated through targeted analyses, including ICP-OES / ICP-AES following suitable sample preparation. Comparing several samples can help identify changes or differences in composition.

Explore our ICP-OES / ICP-AES analyses.

Organic Compounds

Depending on the target substances and their properties, an approach using GC-MS or LC-MS/MS may be considered. The laboratory checks whether the technique is suitable for the sample matrix and expected concentrations.

Testing for a known compound and investigating an unknown contaminant do not necessarily require the same analytical programme. Feasibility is assessed before the service is defined.

GC-MS Analysis | LC-MS/MS Analysis

How Can the Source of Contamination Be Investigated?

Analysing a contaminated sample provides information about that particular sample. Investigating its origin often requires comparison samples and an accurate timeline.

Depending on the circumstances, the investigation may compare:

an affected product and a control product;
several batches manufactured on different dates;
raw materials from different suppliers;
samples collected before and after a process stage;
an unknown particle and a material that may have generated it;
a deposit and residues from equipment;
samples collected before and after cleaning;
sampling or container blanks, where relevant.

An analytical similarity is an indication, but not necessarily proof of origin. Results must be interpreted alongside sampling conditions, process history and other possible explanations.

The Stages of an Investigation

Describe the incident: specify when it appeared, the affected batches, the observed defect and any recent changes.
Define the hypotheses: consider raw materials, equipment, the environment, cleaning, packaging and transport.
Develop a sampling plan: select affected samples, controls and potential sources for comparison.
Assess feasibility: review the available quantity, possible preparation procedures, techniques and expected performance.
Perform the analyses: carry out observations, targeted testing or quantification according to the agreed programme.
Interpret the results: examine differences, similarities and the limitations of the conclusions.
Define further investigations: where necessary, propose additional comparisons or testing after corrective action.

Preserving Samples Before Analysis

Contact the laboratory before cleaning, dissolving, grinding or transferring a particle. Unsuitable preparation may alter the contaminant or remove useful information.

photograph the defect and its location before handling;
keep affected samples and controls separate;
label each container with a unique reference;
record the sampling conditions and date;
avoid handling that could introduce additional contamination;
ask BJL to confirm suitable containers and shipping conditions.

The required quantity depends on the material and proposed analyses. For an isolated particle or a sample available in very limited quantities, the strategy should be agreed before shipment.

What Information Should You Provide to BJL Laboratoires?

The sample matrix: water, liquid, powder, material, product, deposit or dust.
The observed problem: a particle, a change in composition, a residue or an unusual result.
The timeline: first occurrence, frequency and preceding operations.
The affected batches: number, dates and availability of unaffected batches.
Recent changes: supplier, raw material, maintenance, cleaning or process settings.
Suspected contaminants: substances, elements or materials, where known.
Available information: photographs, previous reports and relevant technical details.
Available samples: quantities, controls and comparison materials.
Your objective: identification, quantification, comparison or investigation of a possible source.
Your required turnaround time.

What Results Can You Expect?

Depending on the agreed programme, the service may provide microscopic observations, elemental composition, identification of target compounds, concentrations or comparisons between samples.

Conclusions are limited to the information accessible through the techniques used and the samples received. The origin of contamination cannot always be determined from a single analysis.

If an existing method needs to be adapted to your matrix or objective, an analytical method development study may be considered.

Contamination and Non-Conformity Investigations

A contamination investigation focuses on the presence of unwanted material and its possible sources. It may form part of a broader non-conformity investigation involving an out-of-specification result, differences between batches or a change in process performance.

Explore our analytical non-conformity investigation service.

Contamination Investigation Costs and Turnaround Times

The cost depends on the number of samples, the preparation required, the selected techniques and the level of interpretation requested.

An initial targeted phase can be defined and then extended according to the results obtained. BJL specifies the scope of the service and the expected turnaround time in its proposal.

Frequently Asked Questions

Can an Unknown Contaminant Be Analysed?

Yes. A feasibility assessment can begin with a description of the problem and photographs. The laboratory then determines which techniques may provide useful information.

Is One Analysis Enough to Identify the Source?

Not always. Comparison with a control sample, a raw material or a suspected source material is often needed to examine possible origins.

Can I Send a Very Small Particle?

Feasibility depends on its dimensions, nature and how it can be handled. Contact the laboratory before collecting or transferring it.

Should I Provide an Uncontaminated Sample?

Where available, a comparable control sample can help distinguish the material’s normal constituents from potential contamination.

Can the Laboratory Assess a Corrective Action?

A comparison programme before and after the intervention may be proposed. Sampling conditions must allow a meaningful comparison.

A Laboratory in France for Your Investigations

BJL Laboratoires, based in Sèvres near Paris, supports industrial companies, engineering consultancies, quality departments and environmental professionals.

Sample acceptance and transport conditions must be confirmed before shipment. For samples sent from abroad, consult our international sample shipping information.

Describe Your Contamination Problem

Provide details of the sample, your observations, available photographs and suspected sources. BJL Laboratoires will assess a suitable analytical approach.

Request a Feasibility Assessment