Metal limits are set element by element, for a named product. Pesticide limits are set for the raw plant, and extraction changes the figures.
Two short rows sit near the end of a botanical extract specification: heavy metals and pesticide residues. They are easy to read as a formality, a figure or the word “complies”, and on to the next row. Each of them stands for a set of legal limits, and those limits depend on the element or the pesticide, on the product and on the market.
Here are six checks to make on these two rows, with the rules of the European Union, Great Britain and the United States behind them. Our earlier articles covered the specification, the extract ratio, the Certificate of Analysis, and the solvent and carrier; this one stays with metals and pesticides.
01 / THE METALS ROW
Does the row give a limit for each metal?
Many specifications carry a single row for heavy metals, with one figure, such as 10 ppm, for all of them together. European Union food law has no such total. Its maximum levels are set element by element, and for food supplements there are three: lead 3.0 mg/kg, cadmium 1.0 mg/kg (3.0 for supplements made mainly from seaweed or bivalve molluscs) and mercury 0.10 mg/kg.2 Great Britain sets the same three figures in its own version of the earlier regulation.3
One mg/kg is one ppm. A total of 10 ppm is higher than each of the three levels, so a row that gives only a total cannot show that any one of them is met. A limit, and later a result, is needed for each element.
A fourth element, arsenic, often has a row of its own. The European Union regulation has an arsenic section, with levels for foods such as rice, fruit juices and salt, and no entry for food supplements.2 European guidance for herbal medicines takes its metal limits from the pharmacopoeia and adds that for metals not listed there, “acceptance criteria should be based on safety considerations”; whether to test for other toxic elements, arsenic among them, is to be examined “using a risk assessment approach”.1 An arsenic limit on a specification therefore comes from somewhere else, such as a pharmacopoeia monograph or a company’s own decision. Ask which.
Check: that the specification gives a limit for each element, at least lead, cadmium and mercury, rather than one total, and where the arsenic limit comes from.
02 / THE PRODUCT
Which product is each limit set for?
A maximum level belongs to a product. The European Union levels “shall apply to food as placed on the market”, and the three figures above are the ones for food supplements. For the same metal the regulation sets other levels for other products: for lead in dried spices, from 0.60 mg/kg for fruit spices to 2.0 mg/kg for bark spices.2
An extract supplied to a company that makes supplements is an ingredient, not the product the level was written for. For a processed or compound food that has no level of its own, the regulation requires account to be taken of “changes of the concentration of the contaminant caused by processing”, and in an official control the food business operator “shall provide and justify the specific concentration, dilution or processing factors”.2
Check: for each limit, the product it applies to, whether the extract as supplied or a finished product, and the regulation or pharmacopoeia it is taken from.
03 / THE PESTICIDE ROW
What does the pesticide row refer to?
The pesticide row usually shows no figure. It names a rule, such as Regulation (EC) No 396/2005 or a pharmacopoeia chapter. European guidance for herbal medicines accepts either: “For pesticide residues, the acceptance criteria of the Ph. Eur. (2.8.13.) or the acceptance criteria of Regulation (EC) 396/2005 should be applied, unless otherwise justified.”1 Ph. Eur. is the European Pharmacopoeia.
Behind the reference stands a table. In the European Union regulation a maximum residue level, or MRL, is “the upper legal level of a concentration for a pesticide residue in or on food or feed”, set pesticide by pesticide and product by product; where no specific level is set, the default is 0.01 mg/kg.4 Great Britain keeps its own register of levels with the same default, and its regulator notes that “GB MRLs and EU MRLs may become different over time”.6
So the word “complies” is complete only with three things beside it: the rule, the market whose levels were applied, and the list of pesticides the test covered. A result of “not detected” depends in turn on the lowest concentration the method can measure, which the regulation calls the limit of determination.4
Check: the rule the pesticide row refers to, the market whose levels were applied, the pesticides the test covered, and the lowest concentration the method can measure.
04 / CONCENTRATION
Were the limits applied to the plant or to the extract?
Pesticide levels are set for raw commodities, not for extracts. For processed products the European Union regulation applies the level of the raw product, “taking into account changes in the levels of pesticide residues caused by processing and/or mixing”.4 A note from the European Commission’s services counts “plant extracts” among processed products and describes the tool, a processing factor: “the ratio of the residue concentration in the processed product and the residue concentration in the relevant unprocessed product”. A factor above 1 means “Residues concentrated in the processed product”.5 Great Britain’s regulator describes the same approach.6
The regulation itself lists no such factors: the annex that could hold them “has not yet been established”, and the note warns that “processing factors are product and substance specific”.5 An extract made at 10:1 shows why: ten kilograms of plant material go into one kilogram of extract. A residue that passes completely into the extract arrives at ten times the concentration; one that the solvent does not dissolve arrives at less. European medicines guidance says as much about solvents that dissolve fats and oils, asking for attention to “pesticide residues and mycotoxins that are soluble in lipophilic solvents and so can be concentrated in herbal preparations prepared with lipophilic extraction solvents”.1
Metals follow the same logic. The guidance accepts plant material above the pharmacopoeia’s limits for heavy metals only “provided that the resulting extract satisfies these requirements”, and it asks for justification “that the contaminants do not accumulate during the manufacturing process”.1 United States law sets the bar differently for pesticides: where the raw commodity has a tolerance and the processed food has none of its own, the residue is accepted only if its concentration “is not greater than the tolerance prescribed for the pesticide chemical residue in the raw agricultural commodity”.8
Check: whether each limit was applied to the plant material or to the extract and, where a processing factor was used, its value and the data behind it.
05 / THE BATCH
Was this batch tested for them?
A specification states limits. Whether a given batch was tested against them is a separate question. European medicines guidance says that “Testing of these contaminants in the herbal preparation is usually considered not necessary if tested on the herbal substance”, meaning the plant material before extraction, and that “Periodic/Skip testing of contaminant residues may be acceptable where justified”.1
The same guidance says what such a justification should weigh: the plant material and how it is grown, “possible contamination from neighbouring farms, geographical origin”, and, for metals, “the plant specific ability to accumulate heavy metals/toxic elements”.1 A buyer can ask the same things: where the plant was grown, whether it was cultivated or collected wild, and how often the contaminant tests are run. Our article on the Certificate of Analysis explains periodic testing and what a certificate shows for the batch in hand.
Check: whether the metal and pesticide results come from this batch of extract, from the plant material or from periodic testing, and how often the tests are run.
06 / YOUR PRODUCT
What do the two rows mean for your finished product?
The legal levels apply to your product as you sell it, and the extract is one part of it. A supplement that contains 20% of an extract receives one fifth of the extract’s lead; the other ingredients add their own. The regulation’s phrase for this is “the relative proportions of the ingredients in the product”.2 Work back from the level your product must meet to the limit you need on each ingredient.
In the United States, the rule on specifications for dietary supplements gives no figures for metals. It requires the company that makes a supplement to establish, for each component it uses, “limits on those types of contamination that may adulterate or may lead to adulteration of the finished batch of the dietary supplement”.7 The limits on the ingredient are then yours to set.
Check: the levels your finished product must meet in its market, the share of the extract in it, and the limit that leaves for the ingredient.
WHAT TO SEND
State your limits with your enquiry
When metal or pesticide limits matter to your product, tell us:
- the ingredient, and the plant part if more than one is offered;
- your intended application and destination market;
- the limits your quality team applies for lead, cadmium, mercury and arsenic, and the rule they come from;
- the pesticide residue rule your product must meet;
- whether you need metal and pesticide results for each batch;
- which technical documents you need, such as a specification sheet or Certificate of Analysis;
- your name, company and contact details.
We offer technical documentation and COA support, and the available document set is confirmed for each ingredient and project. Specification ranges in our catalogue are references, and feasibility, availability and price are confirmed with your quotation.
This article describes legal limits and gives no values for YOHOLIFE® ingredients; the specification and documents for a selected grade are confirmed when you enquire. Source 1 was written for medicines and is cited here for its approach; sources 2 to 6 are European Union and Great Britain food law and official explanations of it; sources 7 and 8 are United States law. Legal references were checked on 12 November 2026 and are given for orientation, not as regulatory advice.
