Carbofuran, Methomyl to drop out of Chinese market

- Will the withdrawal of carbofuran and methomyl products benefit other products, such as carbosulfan?
- Is it possible for Chinese companies to invest in formulation manufacturing plants overseas?

On September 7, 2023, the Chinese Ministry of Agriculture and Rural Affairs gave an instruction prohibiting four high-toxic pesticides, which stipulates that from December 1, 2023, the issuing authority will revoke the formulation registration of omethoate, carbofuran, methomyl and aldicarb. Therefore, the production of the four products will be prohibited while products made lawfully can be sold and used within the shelf-life period, but will be prohibited from sales and use from December 1, 2025. Manufacturers’ technical material production for exports is still valid, which should continue to operate under supervision. The instruction given by the ministry represents the end for carbofuran, a product that has been used in China for more than half a century since its market launch in the 1970s, in the Chinese agricultural market.

Carbofuran is a carbamate miticide, insecticide and nematicide jointly developed by FMC and Bayer. The product is systemic, contact and stomach toxic, being also ovicidal, with a long-lasting effect.

Carbofuran is also an AChE inhibitor, but what makes it different from carbamate insecticides is its irreversible binding with cholinesterase, making it highly toxic.

Currently, carbofuran is widely used on non-crop gardens, green plants and ornamental plants, but its use it not allowed for vegetables, fruit trees, tea trees and Chinese herbal medicines.

So far, as per China Pesticide Registration Watch there are 141 valid registrants in China, including 4 TC registrations, while formulations are mostly FSC.

Synthesis processes

There are three synthesis processes using benzofuranol as the starting raw material, which are the following:

Process 1: Methyl isothiocyanate (MIC) process, where MIC reacts with benzofuranol in the presence of a catalyst. The reaction formula is as follows:

Process 2: Chloroformate process, where benzofuranol firstly reacts with phosgene in the presence of catalyst, resulting in chloroformate furanophenol, added with methylamine for aminolysis. The reaction formula is as follows:

Process 3: Carbamoylchloride (MCC) process, where phosgene reacts with methylamine in a T-shaped tube at 300 °C, resulting in MCC, which reacts with benzofuranol. The reaction formula is as follows:

As shown by comparison, Process 1 has the advantages of high yield (98%, based on benzofuranol), superior quality, short production cycle, no generation of sewage, and continuous production run. Its disadvantages include a large initial investment, high equipment requirement, high toxicity of MIC and the slightly poor product color. The advantages of Process 2 are its high product content, white color and small initial investment. Its disadvantages are low yield (90 to 92%), long production cycle, generation of large amounts of sewage and high safety operation requirements. In contrast, Process 3 has the advantages of high yield (≥97%), superior quality, white color, small initial investment, easy availability of equipment and materials, safe and convenient operation, and the generation of slightly larger amounts of sewage. In general, from the perspectives of availability of raw materials, simplicity of process, cost of production, ease of industrialization, investment requirement, and safe and convenient operation, the MCC process is more suitable for the industrialized production of carbofuran.

Considerations on carbofuran’s market exit

Carbofuran is a broad-spectrum, high-effective and low-residue insecticide widely used in agricultural production. However, in recent years, it has been phased out gradually, and it will definitely drop out from the Chinese market by the end of 2025, which is a major change within the industry and will have certain effects on the Chinese agriculture.

Although other substitute insecticides are available, they do not have carbofuran’s broad-spectrum effects and high effectiveness. Therefore, the agricultural industry needs to find an appropriate alternative, which requires more time and resources. Moreover, the market exit of carbofuran may cause difficulties in controlling some insect pests, meaning that farmers must increase their labor intensity and input costs. Nevertheless, in the long-term, this is a necessary step towards sustainable agricultural development and is also an inevitable step in the course of development of environmentally-friendly agriculture.

If you have any questions or issues regarding products during your sourcing from China, including price trends, bans or phase-outs, supply status, etc., please contact us at agropages@vip.163.com for more detailed information.