Seed contaminants and tolerance tables

​​​​​All seed consignments imported into Australia for all end uses must meet the standards for seed contaminants and tolerances set by Department of Agriculture.

Check the guidance on this page and import conditions in the Biosecurity Import Conditions system (BICON) to understand the requirements you must meet when importing seeds to Australia.

For the purposes of biosecurity, contamination risks of imported seed consignments include: soil, live insects/snails, seed species that have been assessed as a weed risk, unidentified seeds, fungal mycelium (sclerotia), animal faecal matter and plant material.

How are contaminants identified?

Contamination can be identified by inspection of the consignment and/or based on laboratory analysis of a submitted seed sample from the seed lot. Seed inspection requirements vary based on the seed lot size and size of the seed. As a general rule, the department has adopted the following policy for seeds:

For seed lots less than 10 kg OR seed lots containing seed greater than 8mm diameter

  • The seed lot is subject to inspection by a biosecurity officer on arrival in Australia.
  • The seeds will be inspected visually to assess contamination.
  • If contamination is found, a sample must be drawn in accordance with International Seed Testing Association (ISTA) procedures and submitted to a department approved seed testing laboratory for analysis.

For seed lots greater than 10 kg AND containing seed less than 8mm diameter

  • The seed lot must be sampled in accordance with International Seed Testing Association (ISTA) procedures and methodology, and sample(s) forwarded to a department approved laboratory for analysis.
  • An importer may elect to have this performed offshore or on arrival in Australia.
  • The results of the seed analysis must be presented an official Seed Analysis Certificate, ISTA Orange Certificate or NAL Certificate.
  • The certificate will outline what contamination is present in the sample (purity and other matter).

Note: Further information on ISTA is available at

Can I assess my own certificate?

If you choose to have your consignment tested offshore (i.e. prior to arrival in Australia), you may wish to assess the certificate yourself. By assessing the certificate prior to shipping your goods, you may be able to determine whether there are any contamination issues with your consignment and therefore, allow you to remediate the consignment prior to shipping, if necessary.

Please note the department will still need to assess the certificate on-arrival.

Below are the contaminant and tolerance standards seed consignments must meet for:

  • soil
  • contaminant seeds
  • sclerotia
  • animal faecal matter.


Seed must be free of soil. Soil is not always readily visible, but 0.1% has been adopted as the standard maximum tolerance. Seed contaminated with soil above this tolerance must be cleaned, exported or disposed of.


Levels of soil contamination reported on seed analysis certificates are to be rounded to 1 decimal place for assessment purposes. For example:

0.14 per cent would be rounded down to 0.1 per cent and is therefore, below the tolerance level

0.15 per cent would be rounded up to 0.2 per cent and is therefore, above the tolerance level.

Contaminant seeds

Contaminant seeds are grouped into two key categories:

All contaminants detected in a consignment must be assessed. If a consignment contains both acceptable and unacceptable contaminants (i.e.restricted seed species exceeding the tolerance level specified below, species listed as having a nil tolerance, etc.) the consignment is NOT OK.

Restricted seeds

Table 1. Maximum contaminant seeds per kilogram (kg) for restricted seeds
Seed Tolerance (seeds per kg)SeedTolerance (seeds per kg)
Agropyron spp.35 Medicago falcata60
Avena spp.35 Medicago glutinosa60
Brachiaria spp.60 Medicago media60
Cajanus spp.60 Medicago sativa60
Calopogonium spp.35 Melilotus alba60
Carthamus tinctorius35 Melinis spp.250
Cenchrus spp. (other than C. gracillimus)35 Onobrychis spp.250
Centrosema spp.60 Oryza sativa5
Chloris spp.35 Panicum spp.250
Citrus spp.Nil Pennisetum spp. (other than P. macrourum)125
Cyamopsis tetragonolobus35 Phaseolus spp.25
Desmodium spp.45 Pueraria spp.45
Digitaria spp.125 Secale cereale35
Eucalyptus spp.Nil Sesamum indicum60
Glycine spp.60 Setaria spp. (other than S. faberi)250
Gossypium spp.Nil Sorghum spp. (other than S. almum and S. halepense)35
Hibiscus cannabinus60 Stylosanthes spp.35
Hordeum spp.35 Triticum spp. seed from Karnal bunt countries (b)Nil
Lablab purpureus35 Triticum spp. seed from non-Karnal bunt countries (b)35
Lactuca spp. (a)250 Vicia spp. (other than V. faba)35
Leucaena spp.25 Vicia fabaNil
Linum usitatissimum45 Vigna spp.25
Lotononis spp.250 x Triticosecale spp. (Triticale) seed from Karnal bunt countries (b)Nil
Manihot esculenta25 x Triticosecale spp. (Triticale) seed from non-Karnal bunt countries (b)35
-- Zea spp.Nil

a excluding Lactuca capensis, Lactuca denticulata, Lactuca pulchella and Lactuca taraxacifolia.
b Karnal Bunt (Tilletia indica) is known to occur in the following countries: United States of America, Mexico, Brazil, India, Iran, Pakistan, Nepal, Afghanistan, South Africa and Iraq.

Seeds with nil tolerance

Seeds with a nil tolerance include:

  • any species listed on BICON as not permitted entry
  • any species listed on BICON as having additional requirements, e.g. requires an import permit, testing, etc.
  • any species not listed on BICON or specified in a list prepared by the Director of Biosecurity and published on the department’s website
  • any seed that cannot be identified to species level
  • any species listed in Table 2 when being imported into the defined state. Note: For all other states and territories these species are permitted entry as contaminants.

Contaminant seeds not listed on BICON or not identified to species level require an assessment by the department's Plant Import Operations Program prior to any action being taken.

Table 2. Seeds with nil tolerance when being imported into the defined state
Seed State
Convolvulus arvensisWestern Australia, South Australia, Victoria
Galium aparineWestern Australia
Galium spuriumTasmania
Galium tricornutumWestern Australia, Tasmania, certain parts of South Australia

Sclerotia and Ergot

The following sclerotia (fungi) are not of biosecurity concern, and may be imported without mandatory seed cleaning.

  • Claviceps purpurea
  • Claviceps paspali
  • Sclerotinia sclerotiorum
  • Sclerotium bataticola
  • Sclerotium rolfsii.

*  Fungi in the genus Claviceps is commonly referred to as Ergot

A contamination tolerance level of 0.05% is permitted:

  1. For any species not listed above; or
  2. Where contamination cannot be identified down to a species level in a consignment.

NOTE: For seed lots of Lolium spp. or Festuca spp. no action is required when ergot or sclerotia is detected.

Alternatively, the department can undertake an assessment of a new contaminant species not listed above. Please note assessments are subject to Departmental resources, and may take several weeks.

Animal faecal contamination

Consignments must be free of animal faecal contamination. All reports of faecal contamination on seed analysis certificates must be referred to the Canberra office (Plant Import Operations) for advice.


  • For consignments of imported pasture seed (such as Lolium spp., Festuca spp., Poa spp, Agrostis spp) only.
  • A tolerance of 0.01% is permitted for rodent faecal contamination for pasture seed consignments exported from the United States only. The level of rodent faecal contamination (as a percentage) must be stated on an ISTA laboratory report.
  • Consignments are subject to inspection on arrival, to verify freedom from live rodents. There is no tolerance for consignments detected with live rodents.
  • For consignments detected with rodent dropping contamination and no ISTA certification, the seed lot will be subject to an onshore sample being drawn in accordance with ISTA methodology and forwarded to a department approved laboratory for purity testing to determine the percentage of rodent droppings.