Saltee Plaza, 1 K B Sarani, Room 313, Kolkata 700080Call +91 93306 64877sadguru.laboratory@gmail.com
Contaminants

Heavy metals and pesticide residue testing

Contaminant testing is about substances that should not be there at all, or only in trace amounts. Heavy metals accumulate from soil, water, processing equipment and packaging; pesticide residues come from the field. Both are regulated by maximum limits, and destination markets are often stricter than domestic ones.

Two families
Metals · pesticide residues
Sample needed
500 g food, 1 L water
Export note
Test to the buyer’s limit
Common use
COA, brand due diligence

What we screen for

Maximum limits are commodity specific — the permitted lead in a leafy vegetable differs from that in a spice or a beverage. Tell us the commodity and the destination market and we will scope to the stricter of the two.

ContaminantTypical route inCommonly tested in
Lead (Pb)Soil, old plumbing, pigments, equipmentSpices, produce, water, sweets
Cadmium (Cd)Contaminated soil and fertiliserLeafy vegetables, rice, cocoa
Arsenic (As)Groundwater — a known Bengal issueWater, rice, produce
Mercury (Hg)Industrial contamination, bioaccumulationFish and seafood
Tin (Sn)Leaching from cansCanned foods and beverages
Copper and zincEquipment and processing aidsBeverages, processed foods
Organochlorine residuesPersistent field applicationProduce, tea, spices
Organophosphate residuesField application close to harvestVegetables, fruit, grain
Synthetic pyrethroid residuesField and storage applicationProduce, stored grain
Fumigant residuesPost-harvest storage treatmentGrain, pulses, spices

What to send us

Quantity
500 g of food drawn across the lot, or 1 litre of water. Residue work needs more sample than a chemical panel
Container
Glass or a new food-grade pouch. Never send a residue sample in a reused plastic container
Hold time
Send fresh produce chilled and promptly; dry commodities are less urgent
Full collection instructions →

Arsenic in Bengal groundwater

Parts of West Bengal — notably belts in Nadia, Murshidabad, North 24 Parganas and Malda — have arsenic in groundwater well above the drinking water limit. It has no taste, smell or colour, it is not removed by boiling, and standard filters do not touch it. If your water comes from a borewell in one of those districts, arsenic is not an optional add-on to the panel. It also enters the food chain through irrigation, which is why rice from affected areas is worth testing.

Questions about this test

Which limit applies — Indian or the destination market?

For an export consignment, whichever is stricter, because the consignment has to clear both. Send the buyer specification with the enquiry and we will scope against it rather than the domestic default.

Can boiling or filtering remove arsenic?

No. Boiling concentrates it. Ordinary candle and carbon filters do not remove it either — specific media or reverse osmosis are needed, and either way you need a test first to know the starting level and afterwards to confirm the treatment works.

How many pesticides can you screen for?

A screen covers a defined panel of compounds rather than everything. Tell us the crop and the region and we will select the panel around what is actually used there, which is more useful than a longer list of irrelevant compounds.

Request this testAsk on WhatsAppUpdated 16 September 2026