In August 2023, the European Food Safety Authority (EFSA) completed the peer review of the re-reviewed risk assessment reports for several substances and published the conclusions of the assessment. These substances include the herbicide metribuzin, the fungicide folpet and metconazole, which have been receiving widespread attention.
metribuzin
Azinone is a triazinone herbicide developed by DuPont in the United States. It plays a herbicidal activity by inhibiting photosynthesis of sensitive plants. After application, the germination of sensitive weeds is not affected, and the leaves are chlorinated after emergence. It is mainly used to control annual broad-leaved weeds and some grass weeds.
At present, azinoxone has been approved for market in many countries and regions, such as China, Australia, the European Union, the United States, Brazil and so on. As of August 2023, 21 original drugs and 100 preparations have been registered in China.
The EFSA Peer reviewed Conclusion report of Azinoxone was published on August 24, 2023. In the report, the European Union first affirmed the efficacy of azinoxone as a herbicide on potatoes and soybeans, and then evaluated azinoxone in terms of human health, environmental non-target organisms and environmental impacts. The results are as follows:
(1) Non-dietary exposure risks for bystanders and residents exceeded AOEL values in all representative uses.
(2) The risk to birds, mammals, aquatic organisms and soil organisms is low; When used in potatoes, azinoxone presents a high field risk to non-target arthropods. In addition, in all representative uses, the high risk of azinoxone for bees cannot be ruled out.
(3) Azinoxone is identified as an endocrine disruptor of the human thyroid hormone (T) pathway.
In addition, EFSA concluded that there are still some data gaps, and the risk assessment related to diet and drinking water has not been finalized.
While EFSA concluded that azinoxone may produce endocrine disrupting effects mediated through the thyroid hormone (T) pathway in humans, the current results also show that the associated endocrine disrupting effects have a significant toxicity threshold. Therefore, there is no final conclusion as to whether the endocrine disrupting effects of azinoxone will lead to its banning in the EU, and further exposure and risk assessments are required.
2 Sterile Dan (folpet)
Bactericide is a contact fungicide developed by Chevron Chemical Company. It interferes with the respiratory action of fungi through S-H bond binding, and prevents and protects many leaf diseases of cereals and fruit and vegetable crops, and has good preventive and protective effects on downy mildew and leaf spot. Sterilized Dan is mainly used to control potato late blight, powdery mildew, leaf rust and leaf spot of other crops, and some diseases of grapes.
At present, sterilization Dan in China, the European Union, Brazil, New Zealand and other countries and regions approved for listing. As of August 2023, Germicidal Dan has two original drug registrations and three preparation registrations in China.
The EFSA Peer Review Conclusion report for Sterilized Dan was published on August 18, 2023. The report showed that no critical areas of concern were identified in the assessment of human health, environmental non-target organisms and environmental impacts. Specific conclusions are as follows:
(1) The groundwater model showed that in one of seven scenarios for a representative use, the groundwater associated metabolite phthalamic acid exceeded the 0.1 μg/L limit in one scenario.
(2) In some representative uses, germicidal Dan has a high risk to non-target arthropods other than birds, mammals, bees, and earthworms; In all representative uses, sterilized Dan has a high risk to aquatic organisms; In all representative uses, Germicidal Dan has a low risk to non-target soil dwellers, non-target land plants and microorganisms.
(3) Germicidal Dan does not meet the endocrine disruptor identification criteria for human and environmental non-target organisms (that is, it is not an endocrine disruptor).
In addition, EFSA's conclusions show that there are still some data gaps and that the residual results have not yet been finalized.
According to the current EFSA evaluation results, there are no major negative conclusions, and if some current problems can be actively addressed in the future, sterilized Dan is expected to successfully pass this rereview.
metconazole
Phyllobactericide is a triazole fungicide jointly developed by Kureha Chemical Company of Japan and Cyanamide (now BASF) Company of the United States. The mechanism of action is the same as other triazole fungicides, which is an inhibitor of C-14 demethylation in ergosterol biosynthesis (FRAC: 3), and prevents pathogen spores from invading crop tissues by inhibiting the elongation of pathogenic bacteria mycelia. Phyllobacteriazole is a kind of broad-spectrum absorbent fungicide with excellent activity, which is mainly used to control the sphaerium, Fusarium paniculata, leaf rust of wheat, dwarf rust of barley, powdery mildew, crown rust of oats and so on.
At present, the market of phyllobacterazole is mainly concentrated in Europe, South America and other places, and has been approved for listing in Brazil, North America, the European Union, the United Kingdom, Japan and other countries and regions. As of August 2023, there are only 2 original drug registrations and 2 preparations registered in China.
The peer-reviewed conclusion report on phyllobacterazole was released on August 24, 2023. In the report, the EU recognized the efficacy of phyllobactericidal and plant growth regulation, and then evaluated phyllobacterazole in terms of human health, environmental non-target organisms and environmental impacts, with the following results:
(1) When phyllobacterazole is used in rape, the exposure risk of bystanders and residential children is higher than that of users.
(2) The estimated residue of phyllobacterazole related metabolites did not exceed the toxicological reference value.
(3) In all representative uses, the risk to birds, wild mammals, bees, non-target arthropods, earthworms, soil microorganisms, non-target land plants, and wastewater treatment organisms was low.
(4) Phyllobacterazole does not meet the criteria for the identification of endocrine disruptors in human and environmental non-target organisms (that is, it is not an endocrine disruptor).
In addition, EFSA's conclusions show that there are still a number of data gaps, resulting in the drinking water and the corresponding population risk assessment has not been finalized.
No critical areas of concern were identified in the assessment of human health, environmental non-target organisms, and environmental impacts, and no potential endocrine disrupting effects of phyllostazole on human and environmental non-target organisms were identified.
4 Follow-up review steps
In the next step, the European Commission (EC) will analyse the conclusions of EFSA and the Rereview Assessment Report (RAR) and will submit the rereview report and draft regulation to the Member States to recommend the continuation or non-continuation of the authorisation of bactericidin, Azalone and phyllostazole. Representatives of EU member states will then vote on the draft regulation at the Standing Committee on Plants, Animals, Food and Feed (SCoPAFF).
The latest progress of phyllobacterazole, azidone and germicide was reviewed
2023 09/11