Mycotoxins are toxins produced by moulds that grow on a crop in the field or in storage. Polycyclic aromatic hydrocarbons, or PAHs, reach plant material from the environment or from the way it is dried. On a specification, each of their limits belongs to named substances, a named material and a market.
Near the end of a botanical extract specification there may be rows for aflatoxins, ochratoxin A and polycyclic aromatic hydrocarbons. Their figures are very small, and often there is only the word “complies”. Many specifications carry no such rows at all, and then the first question is why.
Here are six checks to make on these rows. They draw on the food law of the European Union and of Great Britain, on European guidance for herbal medicines, and on United States rules and guidance. Our earlier articles covered the specification, the extract ratio, the Certificate of Analysis, the solvent and carrier, the heavy metal and pesticide rows, the assay method, the microbiological rows, the identification row, the physical rows and the shelf life; this one stays with mycotoxins and PAHs.
01 / THE SUBSTANCES
Which substances does each row name?
“Mycotoxins” is a family name, and so is “PAHs”. A limit is always set for particular members of the family. For most of the foods it lists, European Union law sets two aflatoxin figures side by side: one for aflatoxin B1 alone, and one for the sum of aflatoxins B1, B2, G1 and G2.1 The recitals of the 2006 regulation that still applies in Great Britain, the numbered reasons printed before its articles, explain why: the total is limited “as well as the aflatoxin B1 content alone, aflatoxin B1 being by far the most toxic compound”.2
Ochratoxin A is a separate toxin with a row of its own. European guidance for herbal medicines names both when it lists the contaminants to address: “mycotoxins (aflatoxins, ochratoxin A)”.3 Both are produced by moulds: aflatoxins by certain Aspergillus moulds and ochratoxin A by certain Aspergillus and Penicillium moulds, as the United States Food and Drug Administration describes them.4
PAHs are handled in the same way. The European Union sets one level for benzo(a)pyrene and one for the sum of four substances: benzo(a)pyrene, benz(a)anthracene, benzo(b)fluoranthene and chrysene.1 The sum was introduced in 2011, after the European Food Safety Authority had concluded that “benzo(a)pyrene is not a suitable marker for the occurrence of polycyclic aromatic hydrocarbons in food”. With a sum of four, the amending regulation says, PAHs can also be controlled in samples “in which benzo(a)pyrene is not detectable, but where other PAH are present”.5
So a row headed “aflatoxins” with a single figure does not say whether the figure is for aflatoxin B1 or for the four together, and a row for benzo(a)pyrene alone says nothing about the other three PAHs.
Check: which substances each row covers, among aflatoxin B1, the sum of the four aflatoxins, ochratoxin A, benzo(a)pyrene and the sum of the four PAHs.
02 / THE MATERIAL
For which material is each limit set?
A maximum level belongs to a food, and European Union law lists the foods one by one. For aflatoxins the plant materials on the list include a few named dried spices, at 5.0 µg/kg for aflatoxin B1 and 10.0 µg/kg for the sum. For ochratoxin A the list includes dried herbs at 10.0 µg/kg, most dried spices at 15 µg/kg, and a few named dried roots and flowers for herbal infusions at 15 or 20 µg/kg. For PAHs it includes dried herbs, most dried spices, finely ground powders of plant origin that are stirred into drinks, and food supplements containing botanicals and their preparations, each at 10.0 µg/kg for benzo(a)pyrene and 50.0 µg/kg for the sum of four.1 Such preparations, a footnote explains, include extracts.1
That supplement level does not apply to supplements containing vegetable oils: there the oil has to meet the level for oils and fats, 2.0 µg/kg for benzo(a)pyrene and 10.0 µg/kg for the sum.1
What the list leaves out matters as much. It sets no aflatoxin level for dried herbs, and no aflatoxin or ochratoxin A level for food supplements. For mycotoxins and PAHs it sets a level for an extract itself in one entry only, point 1.2.19.2 of the annex. That entry is for the pure and undiluted extract of one root, 1 kg of it obtained from 3 to 4 kg of root, and its level is four times that of the dried root.1
For dried, diluted, processed or compound food that has no level of its own, the levels in the list are applied with four things taken into account. These are “changes of the concentration of the contaminant caused by drying or dilution processes”, changes caused by processing, the proportions of the ingredients, and the limit of quantification of the analysis, the smallest amount it can measure. In an official control the business must “provide and justify” its factors; if it does not, or the authority does not accept them, the authority sets them itself.1 Our article on the heavy metal and pesticide rows works through this reasoning for metals.
Where the list has no level for the plant either, there is no maximum level to carry over. That does not leave the extract without rules. The Union’s general regulation on contaminants forbids placing on the market any food that contains a contaminant “in an amount which is unacceptable from the public health viewpoint”, and requires levels to be kept “as low as can reasonably be achieved by following good practices”. Where no Union level has been adopted, a Member State’s own provisions apply, subject to the Union’s treaties.6
Great Britain keeps its own version of the 2006 regulation. Its PAH levels for dried herbs, dried spices and supplements containing botanicals are the same figures, but its ochratoxin A list has no level for dried herbs, and its level for spices covers a few named spices only.2
Check: for each limit, the material it is set for, whether plant, extract or finished product, the market, and the rule it is taken from.
03 / THE ORIGIN
Is this plant, plant part or process at risk?
The guidance starts from testing, but does not expect every plant material to be tested alike. For mycotoxins, the European questions and answers on herbal medicines say that testing should in general be carried out on herbal substances, their term for the plant material. Routine testing, they add, is not required for all of them, because “only a few herbal substances are at risk of contamination”. They ask for a risk assessment “taking account of the plant and the plant part”, and say that routine analysis should be considered for parts at risk, such as seed, fruit, root and rhizome. Testing should be conducted where the literature reports mycotoxin formation in the plant, or where possible contamination of the plant material is known.7
Moulds need moisture, so harvesting, drying and storage bear on the risk. The same document gives quick drying after harvest, to a loss on drying below 12%, as an example of a measure that reduces it.7 The guideline on specifications links the microbial purity of a herbal substance “to production and storage and to mycotoxin contamination”.3
Our article on the physical rows explains the loss on drying figure, and our article on the microbiological rows the mould count and water activity; a mycotoxin row belongs beside them.
PAHs come from elsewhere. The 2006 regulation describes how: they “can contaminate foods during smoking processes and heating and drying processes that allow combustion products to come into direct contact with food”, and environmental pollution may also cause contamination.2 When the European Union set PAH levels for supplements, dried herbs and dried spices in 2015, it noted that high levels in certain supplements with botanical ingredients “have been linked to the bad drying practices applied to these botanical ingredients” and “are avoidable by applying good practices”. It related high levels in dried herbs and dried spices to bad drying practices as well.8
Extraction comes next. Whether a contaminant follows the plant into the extract depends partly on the solvent. The questions and answers note that “aflatoxins and ochratoxin A are soluble in alcohol”, so that testing of the herbal preparation, their term for what is made from the plant, such as an extract, should also be considered.7 The guideline on specifications asks for particular attention to mycotoxins “that are soluble in lipophilic solvents and so can be concentrated in herbal preparations prepared with lipophilic extraction solvents”, that is, solvents that dissolve fats and oils.3 Our article on the solvent and carrier lines shows where a specification states the solvent.
Check: the plant part, how the material was dried and stored, and the extraction solvent, which all bear on how much these rows matter for the extract.
04 / THE FIGURE
What do the unit, the sum and “not detected” mean?
These limits are written in micrograms per kilogram, µg/kg, which is the same as parts per billion, ppb. A microgram per kilogram is a thousandth of the milligram per kilogram in which heavy metal limits are written, so a figure copied with the wrong unit is wrong by a factor of one thousand.
A sum needs a rule for the substances that were not found. In European Union law the level for the sum of aflatoxins refers to “lower bound concentrations, which are calculated on the assumption that all the values below the limit of quantification are zero”, and the sum of the four PAHs is calculated in the same way.1 A substance too scarce to be measured counts as nothing. A sum reported as zero, or a row marked “not detected”, therefore depends on how little the method can detect and measure. Ask for the limits of detection and quantification of each substance, the smallest amounts the method can detect and can measure, and for the individual results behind a sum.
A level also has a basis. The European Union levels apply, unless the list says otherwise, “to food as placed on the market”, so the PAH level for a supplement is a figure per kilogram of the supplement as sold.1
Check: the unit, how a sum treats results below the limit of quantification, the limits of detection and quantification of the method, and the product for which the level is set.
05 / THE BATCH
Was this batch tested, and by a method shown to suit the material?
A row on a specification states a limit. It does not say that every batch is tested against it, and the guidance does not always ask for that. For plants and plant parts not at particular risk, the questions and answers find that monitoring would in general be enough, and that reduced testing “(or even omission of testing) may be acceptable if justified”.7 For extracts, the guideline on specifications starts from the plant material. Under the European Pharmacopoeia’s monograph on herbal drugs, that is, on plant material, it says, “routine testing or periodic testing, in some cases, is required” for mycotoxins. For the extract, the guideline asks for a justification “that the contaminants do not accumulate during the manufacturing process”. It adds that testing the extract is usually considered not necessary if the plant material was tested, and in its next sentence asks for the particular attention to solvents described in the third check.3
So a mycotoxin or PAH figure on a Certificate of Analysis may have been measured on this batch of extract, measured on the plant material before extraction, or carried over from periodic testing. Our article on the Certificate of Analysis explains periodic testing and why these are different statements.
The method deserves a question of its own. For aflatoxins the guideline points to a method of the European Pharmacopoeia, notes that it has been shown to be suitable for three named herbal substances, and adds: “Its suitability for other herbal substances should be demonstrated or another validated method used.”3 For PAHs it asks for “Suitable validated methods” and for acceptance criteria that are justified.3 Ask which method produced the figure, and whether it was validated for this material.
Check: whether each result comes from this batch of extract, from the plant material or from periodic testing, and which method was used and for which materials it was validated.
06 / YOUR PRODUCT
What do these rows mean for your finished product?
The legal levels apply to your product as you sell it, and the extract is one of its ingredients. In the European Union a supplement containing botanicals must itself meet the PAH level described in the second check.1 Our article on the heavy metal and pesticide rows shows how to work back from the level a product must meet to the limit needed on each ingredient.
In the United States the Food and Drug Administration lists an action level of 20 parts per billion for aflatoxins in foods. Action levels, it says, are “limits at or above which FDA will take legal action to remove products from the market”, not levels of contamination that are permitted where it can be avoided. Its list, dated August 2000, has none for ochratoxin A or for PAHs, and where none exists the agency “may take legal action against the product at the minimal detectable level of the contaminant”.9 The federal rule for dietary supplements sets no figures of its own. For each component the company must set “limits on those types of contamination that may adulterate or may lead to adulteration of the finished batch of the dietary supplement”, and it must set such limits for the finished batch as well.10
In the European Union three rules exclude what might look like ways out when a batch is above a level. Food above a maximum level “shall not be used as a raw material in food or as an ingredient in food”. Food that complies “shall not be mixed with food which exceeds these maximum levels”. And food containing these contaminants may not be “deliberately detoxified by chemical treatments”, whatever the level.1 United States guidance treats blending in the same way: blending a food above an action level with another food “is not permitted, and the final product resulting from blending is unlawful, regardless of the level of the contaminant”.9
In each of these markets the finished product is yours to answer for. So tell your supplier which levels your product must meet, and in which market, and ask for the rows that follow from them.
Check: the levels your finished product must meet in its market, whether any lot was blended or treated to bring it under a level, and the limits you therefore need on the ingredient.
WHAT TO SEND
State your mycotoxin and PAH requirements with your enquiry
When these rows 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 kind of finished product the extract will go into;
- the limits your quality team applies for aflatoxin B1, total aflatoxins, ochratoxin A, benzo(a)pyrene and the sum of the four PAHs, and the rule they come from;
- whether you need mycotoxin and PAH results for each batch;
- whether you will test the delivery yourself, and by which method;
- 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 published law and guidance and gives no mycotoxin or PAH limits, results or test methods for YOHOLIFE® ingredients; the specification and documents for a selected grade are confirmed when you enquire. Sources 1 and 6 are European Union food law in force. Sources 5 and 8 are earlier amending regulations, no longer in force in the Union, cited for the reasons they give. Source 2 is the earlier regulation as it still applies in Great Britain. Sources 3 and 7 were written for herbal medicines and are cited here for their approach; the European Pharmacopoeia methods and limits that source 3 refers to are not reproduced. Sources 4, 9 and 10 are United States public information, guidance and law; the action level in source 9 is set in guidance, not in a regulation. Sources were checked on 13 November 2026 and are given for orientation, not as regulatory advice.
