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European Union - Final Regulatory Action
Thiamethoxam CAS number:
153719-23-4
Date circular:
12/12/2022

Chemical name: (E,Z)-3-(2-chloro-thiazol-5-ylmethyl)-5-methyl- [1,3,5]oxadiazinan-4-ylidene-N-nitroamine

Final regulatory action has been taken for the category: Pesticide

Final regulatory action: The chemical is Severely Restricted

Use or uses prohibited by the final regulatory action:

Uses of thiamethoxam as a plant protection product with the exception of uses in permanent greenhouses.

Pesticide use or uses that remain allowed:

Regulation (EC) No 1107/2009 on the placing on the market of plant protection products:
Commission Implementing Regulation (EU) 2018/785 severely restricted the use of thiamethoxam as plant protection product by only allowing uses as insecticide, in permanent greenhouses or for the treatment of seeds intended to be used only in permanent greenhouses. The resulting crop had to stay within a permanent greenhouse during its entire life cycle.
In the meantime, i.e. on 30 April 2019, the approval of thiamethoxam expired. [Note: All approvals of active substances used in plant protection products are time-limited in the European Union.]
Regulation (EU) No 528/2012 on the making available on the market and use of biocidal products:
Thiamethoxam is approved in the EU under Regulation (EU) No 528/2012 for its use as an active substance in biocidal products for product-type 18- Insecticides, acaricides and products to control other arthropods (pest control). The validity of the approval for PT-18 ends on 31 January 2025.
Commission Directive 2013/3/EU of 14 February 2013 amending Directive 98/8/EC of the European Parliament and of the Council to extend the inclusion in Annex I thereto of the active substance thiamethoxam to product-type 18 Text with EEA relevance. <http://data.europa.eu/eli/dir/2013/3/oj>
Commission Directive 2008/77/EC of 25 July 2008 amending Directive 98/8/EC of the European Parliament and of the Council to include thiamethoxam as an active substance in Annex I thereto (Text with EEA relevance)
<http://data.europa.eu/eli/dir/2008/77/oj>

The final regulatory action was based on a risk or hazard evaluation: Yes

Summary of the final regulatory action:

The final regulatory action, i.e. Commission Implementing Regulation (EU) 2018/785, severely restricting the use of thiamethoxam in accordance with Regulation (EC) No 1107/2009 of the European Parliament and of the Council of 21 October 2009 concerning the placing of plant protection products on the market stipulates the following: Only uses as insecticide, in permanent greenhouses or for the treatment of seeds intended to be used only in permanent greenhouses, may be authorised. The resulting crop must stay within a permanent greenhouse during its entire life cycle.
EU Member States were required, in accordance with Regulation (EC) No 1107/2009, where necessary to amend or withdraw existing authorisations for plant protection products containing thiamethoxam as active substance by 19 September 2018 at the latest.

The reasons for the final regulatory action were relevant to: Environment

Summary of known hazards and risks to the environment:

.It was concluded that only the following uses of plant protection products containing the active substance thiamethoxam may be authorised, as they are expected to satisfy in general the requirements laid down in Article 29(1) of Regulation (EC) No 1107/2009 and the uniform principles laid down in Regulation (EU) No 546/2011:
-Uses in permanent greenhouses or for the treatment of seeds intended to be used only in permanent greenhouses. The resulting crop must stay within a permanent greenhouse during its entire life cycle.
Furthermore, taking into account the risks for bees from treated seeds, the placing on the market and the use of seeds treated with plant protection products containing thiamethoxam should be subject to the same restrictions as the use of thiamethoxam.
On the peer review of the updated pesticide risk assessment for bees for the active substance thiamethoxam considering the uses as seed treatment and granules on 28 February 2018, the following risks to the environment were identified:
Risk to bees via systemic translocation in plants - residues in nectar and pollen:
A high risk at the Tier-1 was concluded for oilseed rape and maize and all bee groups. It should be noted that, in lack of specific toxicity data, the high risks for solitary bees were identified using uniquely surrogate toxicity estimation based on honeybee data (low risk not demonstrated) (treated crop scenario and succeeding crop scenario).
The Tier-2 risk assessment for uses on winter oilseed rape resulted in a high risk for:
oall bee species for uses on winter oilseed rape (treated crop scenario).
obumblebees and solitary bees treated for uses on maize (treated crop scenario).
The Tier-3 risk assessment for uses on winter oilseed rape resulted in a clear high risk for solitary bees, while the conclusion for honeybees and bumblebees was less straightforward (treated crop scenario). Despite clear and consistent effects were not recorded for honeybees and bumblebees, the analysis of the data through a Weight-of- Evidence exercise did not allow excluding the possibility of observing effects larger than negligible on the parameters linked, directly and indirectly, to the respective protection goals.
Risk to bees from contamination of adjacent vegetation via dust drift:
On the basis of the Tier-1 risk assessment, a high risk to all bee groups was indicated for the uses on broccoli, Brussel sprout, cauliflower, head cabbage, kale, lettuce, carrots and maize. Nevertheless, all the previous crops with the exception of carrots
and maize are sown in greenhouses. When these structures are permanent, exposure to bees is considered negligible and a low risk is concluded.
For the uses on winter oilseed rape, a high risk (based on surrogate data) was concluded for bumblebees and solitary bees. The risk assessment for honeybees could not be finalised, in lack of data about chronic toxicity to adults and HPG development (a low risk was nevertheless indicated for acute toxicity to adults and prolonged toxicity to larvae, when a deflector is used).
For the uses on sugar beet (both seeding rates), the risk assessment could not be finalised in lack of data about chronic toxicity to adults and HPG development (whereas a low risk was indicated for acute toxicity to adults and prolonged toxicity to larvae for all bee groups - for bumblebees and solitary bees only when a deflector is used).
Risk to bees via consumption of contaminated water:
The refined risk assessment indicated high risk to honeybees from exposure to guttation fluids for the use in maize.
Furthermore, neonicotinoids insecticides are persistent in the environment, particularly in soil. The mean/median DT50 values for thiamethoxam in soil are 174 days. Thiamethoxam fulfils the criteria for being a vP substance. It might be worth noting that the main soil metabolite of thiamethoxam is clothianidin, so that the DT50 of the active substance alone is not fully representative of the whole exposure time-variable profile.
On the peer review of the updated pesticide risk assessment for bees for the active substance thiamethoxam, the following data gaps were identified:
Risk to bees via systemic translocation in plants - residues in nectar and pollen:
The risk assessment for honeybees could not be finalised, in lack of data about chronic toxicity to adults and HPG development (a low risk was nevertheless indicated for acute toxicity to adults and prolonged toxicity to larvae).
The Tier-3 risk assessment for maize highlighted a low risk for bumblebees. Once again, a definitive conclusion could not be drawn for honeybees and solitary bees based on the available data. This was mainly because the available experiments were not suitable to address the risk due to exposure to contaminated maize pollen, among other reasons. The data did not allow excluding the possibility of observing effects larger than negligible on the parameters linked, directly and indirectly, to the respective protection goals.
Risk to bees via consumption of contaminated water:
In the absence of agreed input parameters for FOCUS surface water modelling, no exposure assessment for the representative uses could be performed. Therefore, the risk to honeybees consuming residues in surface water could not be finalised.
Risk to bees from contamination of adjacent vegetation via dust drift:
For the uses on sugar beet (both seeding rates), the risk assessment could not be finalised in lack of data about chronic toxicity to adults and HPG development (whereas a low risk was indicated for acute toxicity to adults and prolonged toxicity to larvae for all bee groups - for bumblebees and solitary bees only when a deflector is used).
The available data did not allow performing any refined risk assessment for exposure via dust drift.

Expected effect of the final regulatory action in relation to the environment:

Reduction of risk for the environment from the use of plant protection products containing thiamethoxam.

Date of entry into force of the final regulatory action: 29/05/2022

Complete entry into force of all provisions of Commission Implementing Regulation (EU) 2018/785 of 29 May 2018 amending Implementing Regulation (EU) No 540/2011 as regards the conditions of approval of the active substance thiamethoxam was 19 December 2018.