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Testing

T-03

Contaminants and residues

Heavy metals, mycotoxins, pesticide and veterinary residues and process contaminants, measured against the limit that actually applies to your commodity.

What it is
Metals, mycotoxins, residues, process contaminants
Who it is for
Importers, exporters and high-risk commodity handlers
Turnaround
2–10 days

WHAT THIS IS

What this is, and why it matters

Contaminant testing measures substances that should not be present, or should only be present below a stated limit. Four families cover most of the work. Heavy metals — lead, cadmium, mercury, arsenic, tin — arrive from soil, water, packaging or processing equipment. Mycotoxins — aflatoxins, ochratoxin A, deoxynivalenol — are produced by moulds on cereals, nuts, spices, dried fruit and feed. Pesticide and veterinary drug residues carry over from agricultural use. Process contaminants such as acrylamide and histamine are created by the process itself, or by mishandling before it.

This is the testing that carries the highest regulatory consequence in this market. A contaminant exceedance is not a quality problem to be negotiated with a customer — it is a held consignment, a withdrawal, or an enforcement action. It is also the area where a result means nothing without its limit: the same lead value can be compliant in one commodity and an exceedance in another. Every report here states the limit applied and the source of that limit alongside the result, because a number on its own is not a decision.

What this lane covers

  • Heavy metals, mycotoxins, pesticide and drug residues
  • Reported against the specific regulatory or customer limit

TRIGGERS

When you need it

You import or you export

Consignments are cleared against contaminant limits, and a certificate of analysis is routinely part of the documentation. Testing before the consignment moves costs less than testing after it has been held.

Your commodity carries a known risk

Nuts, cereals, spices, dried fruit, rice, fish and animal feed each carry a characteristic contaminant risk. A real supplier approval programme tests that risk on incoming lots rather than filing the certificate the supplier sent with them.

A regulator or a customer has asked

SFDA sampling, a customer audit finding, or a withdrawal elsewhere in your category all generate the same request: current data on your own product, not on a comparable one.

CATALOGUE

Contaminants — parameters

ParameterMatrixReference methodTurnaround
Lead (Pb)Food, feed, waterISO 17294-2 (ICP-MS)5–7 days
Cadmium (Cd)Food, feed, waterISO 17294-2 (ICP-MS)5–7 days
Mercury (Hg)Fish, foodISO 17294-2 (ICP-MS)5–7 days
Arsenic (As, total and inorganic)Rice, food, waterEN 16802 / ISO 17294-25–7 days
Tin (Sn)Canned foodISO 17294-2 (ICP-MS)5–7 days
Aflatoxin B1 and totalNuts, cereals, spices, feedAOAC 991.31 (HPLC-FLD)5–7 days
Aflatoxin M1Milk, dairyISO 14501 (HPLC-FLD)5–7 days
Ochratoxin ACereals, coffee, dried fruitAOAC 2000.035–7 days
Deoxynivalenol (DON)Cereals, feedAOAC 986.175–7 days
Pesticide residues (multi-residue)Produce, cerealsEN 15662 (QuEChERS, GC/LC-MS-MS)7–10 days
Veterinary drug residuesMeat, poultry, dairy, honeyLC-MS-MS screening7–10 days
HistamineFish and fishery productsAOAC 977.13 (HPLC)4–5 days
MelamineDairy, feedLC-MS-MS7–10 days
AcrylamideFried and baked foodLC-MS-MS7–10 days
Total polar compoundsFrying oilAOCS Cd 20-912–3 days

Method references and turnaround times shown are indicative and are confirmed in writing before any sample is accepted.

Figure · Published turnaround spread
Published turnaround spread, grouped from the catalogue above — every line carries a working-day figure. Bands share one axis, so a longer band is genuinely a longer wait.

PROCESS

How it works

  1. Send the brief before the sample

    The commodity, the contaminants in question, and the limit you are being held to — a regulatory limit, a customer specification, or a destination market requirement. Contaminant work is defined by its limit, so this is the first thing the laboratory needs.

  2. Sample requirements confirmed in writing

    Contaminant sampling is where representativeness matters most, because contamination is rarely evenly distributed through a lot — aflatoxin in a nut consignment being the standard example. Sample size, the number of incremental samples and how they are combined are confirmed in writing before you sample.

  3. On the bench, to a published method

    Every determination runs to the ISO, AOAC or APHA method named in the catalogue above, and that reference travels onto the report line rather than sitting in a footnote. Turnaround runs from acceptance at the laboratory, not from the day the sample left you.

  4. Reported so the result can be acted on

    The report states the result, the limit applied, and the source of that limit, so the compliance position is on the page. Results near a limit are reported with their measurement uncertainty, because that is the point at which uncertainty changes the decision.

What you get back

A report stating each contaminant, the method, the measured value, the limit applied and where that limit comes from — the form a customs broker, a customer or an SFDA reviewer expects to receive it in.

Service facts

ParameterValueNote
Live service status[VERIFY: Which testing services are actually LIVE]Published as orderable only when the lab confirms it.
Accreditation positionAccredited. Certificate N-T-00607 covers food and agricultural microbiological testing to ISO/IEC 17025:2017.Stated plainly, never implied by a badge.
Sample requirementsConfirmed to you in writing before dispatch. Container, quantity, temperature and hold time change with the parameter and the matrix, so they are issued per request rather than published as one list.Per-parameter detail publishes with the confirmed method list.

Q+A

Common questions

Contaminants

My customer asked for a “heavy metals test” — which metals do they mean?

There is no single heavy-metals test — the list depends on the product. The applicable limits for contaminants and toxins in food sit under SFDA.FD CAC 193, and the laboratory confirms in writing which metals and which limits apply to your product before testing starts.

Is GSO 2481 the heavy-metals standard?

No — GSO 2481 covers maximum residue limits for veterinary drugs. Heavy metals and other contaminants in food are judged against SFDA.FD CAC 193. The report states which limit each result was compared to, and its source.

Do you report pass/fail or just numbers?

Each result is reported with the limit it was judged against and where that limit comes from. A result without its limit cannot be acted on; with the limit and its source, it becomes a decision you can defend to a customer or an inspector.

Can one sample cover metals, mycotoxins and pesticide residues?

Often, but the quantity needed depends on the panel. The laboratory confirms the required amount in writing before you sample, so you are not asked for more material after the batch has shipped.

A customer rejected a batch for a residue — can you retest it?

Yes, if retained sample from that batch exists — testing a different batch answers a different question. The report states exactly what was tested and against which limit, which is what the customer’s QA team will ask for first.

Send the sample question or the instrument list. It is read by a bench professional, not routed through a ticket queue. Confirmed phone, mailbox and address publish here at launch.