Zeng Dezhi / I object to herbicide as a defoliant for red bean 01: toxicological examination ignores the risk of reproductive poison and completely mispoints the point.

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Wen / Zeng Dezhi (Honorary Professor, Department of Plant Pathology, ZTE University, author of Pesticide Pharmacology and Application)

Although the operating procedure of the competent unit follows the system of administration in accordance with the law, and after two expert meetings, it is still difficult to obtain the recognition of farmers and the general public. A few days ago, the Prevention and Inspection Bureau specially went south to hold a symposium. However, the directors of the five peasant associations in the main red bean producing areas and most of the speakers expressed doubts about the risks and control brought about by grass control, and called on the government not to open up hastily.

After nearly two months of troubles, it is reported that the Council of Agriculture will take the public opinion of the "public policy network platform" as the policy basis, and will soon announce the policy trend recently. based on years of research on pharmacology and the relevant research evidence that has continued to be produced in recent years, the author must honestly tell the Council of Agriculture that it is not appropriate to open up red beans to use fixed weeds as a defoliant.

The reason for the author's objection is that when the herbicide is used as a defoliant, it has a high risk of reproductive toxicity to farmers and consumers (especially pregnant women's embryos), as well as negative effects on liver and kidney. Due to the lack of professional botanist system guidance in agricultural use in Taiwan, and the lack of proper education and training for pesticide application personnel, the risk is difficult to control. The following is the author's detailed explanation, because the length of the article is divided into 3 articles to provide reference from all walks of life.

The research on germicidal reproductive drugs has been approved by the European Union, but Bayer sponsored the writing of the report to reverse the case.

The risk that deserves most attention in the application of herbicide should be the problem of reproductive and neurotoxin, which was not approved by the European Union in 2018. With regard to the problem of herbicide and reproductive toxicity, in fact, scientific evidence has been submitted one after another since 1996, and in the evaluation report made by the European Food Safety Agency (EFSA) for the registration of herbicide in 2005, it is also clear that herbicide can cause serious embryonic development problems without obvious maternal toxicity (maternal toxicity), and its reproductive toxicity is classified as 1B in the report.

In order to overturn the EU ruling that a pair of fixed weeds is equivalent to the need to take off the shelves, Bayer, as the owner at that time, of course quickly tried its best to prove and refute it. Under the financial support of Bayer, a 76-page analysis and review report led by Schulte-Hermann, co-authored by 15 scientific research institutions / community experts and scholars, and a total of 76 pages was released in 2006. It is the main reference material used by Chinese Pharmaceutical Institute to evaluate the toxicity of herbicide.

The Drug Institute cited the 2006 report as its "scientific partner" (screenshot from the website).

Based on the research data collected in that year (including those provided by Bayer) and the understanding of the relevant EU regulations, this report deeply discusses the appropriateness of EFSA to classify the reproductive toxicity of herbicide as 1B, and the report is published by the Journal of controlled Toxicology and Pharmacology (Regulatory Toxicology and Phamacology) as a supplement (2006, 44:S1-S76).

This powerful / persuasive report is presented in the name of the Science Partnership Assessment Panel (Science Partners Evaluation Groups), a private company headquartered in Cambridge, Massachusetts, USA. The correspondent, Professor Gerald N. Wogan, holds the title of fellow of the National Academy of Sciences and retired from the Massachusetts Institute of Technology (MIT) in 2001.

The information submitted by the pesticide manufacturer was not approved by EFSA, and in 2018 it was finally ruled that the herbicide was "not approved".

Although EFSA pointed out that herbicide carries the risk of reproductive poison, thanks to Bayer's efforts, herbicide was approved by the European Commission in 2007, provided that "a risk assessment report on mammals and non-target organisms is submitted within two years". Only according to the 2012 EFSA review report, the subsequent supporting information submitted by the manufacturer has obviously not been recognized by the EFSA evaluation experts. After the manufacturer Bayer took the initiative to withdraw the case in 2017, the EFSA made a final ruling in 2018 on the basis of reproductive drug issues.

Taking a comprehensive view of the above, after more than a decade of controversial attack and defense on registration, manufacturers have indeed tried their best to defend their own rights and interests, but in the end, they have failed. If it is not reasonable, it is not that the trade barrier / market is not as good as ideal (the Prevention and Inspection Bureau originally said that solid grass control is not banned by the European Union, but poor sales actively withdraw from the market) and so on.

The European Union cancelled the license for the use of herbicides after the end of July 2018.

Toxicological examination should examine the existing scientific research reports in an all-round way, so as not to cover the whole.

Since there are many reports in the European Union pointing out the risk of killing grass and breeding poison, and then making a decision of "disapproval", why does the business unit in charge of toxicological safety assessment and review insist on the safety of herbicide and submit a report to the expert meeting at the same time? emphasize that "there will be no doubts about causing reproductive poison under normal use"?

Taking a closer look at the content of the report submitted by the business unit, it is not difficult to find that its argument is mainly based on the above-mentioned analytical report funded by Bayer and published by Schulte- Hermann in 2006. The whole report explains the mechanism of reproductive toxicity with the inhibition of glutaamide synthase (GS) activity as the main axis, and believes that the need for a high dose may lead to a decrease in ammonia detoxification activity and a lack of fetal glutathione supply, resulting in a lack of nutrition, and finally indirectly affect fetal development, and it can be judged that its reproductive toxicity can be classified as a slight grade that can be ignored.

When listening to these relevant narratives in the course of the meeting, the author thinks that the competent unit is too partial to cover all the arguments in toxicology and safety assessment, and lacks professional ability in the omni-directional collection and collection of relevant scientific research reports.

According to the relevant scientific and technological reports that individuals have dabbled in in recent years, studies on the reproductive toxicity of herbicide all focus on the metabolic and neurotoxic problems related to the function of glutamate receptors, and the discussion of the mechanism of action also emphasizes the loss of apoptosis (apoptosis) / gene expression caused by the obstruction of embryonic development and differentiation. The above-mentioned business units in charge of the interpretation of the mechanism of reproductive toxicity is fundamentally wrong. The safety assessment review report completed in this way is indeed very difficult for people to let go of the misgivings about reproductive poison, and therefore, at the meeting, individuals repeatedly stressed that when opening up the use of herbicides as a defoliant for red beans, it is necessary to do the relevant risk control work as a prerequisite.

California enacted legislation as early as 1984 to regulate the "reproductive toxicity" caused by pesticides.

The development of science and technology keeps pace with the times. It has been pointed out in the previous discussion that after the introduction of an important drug, the research and development of related science and technology, including pharmacology and safety assessment, are usually continuous and progressive. When the study found that there may be potential negative effects on the use, it is necessary to make appropriate adjustments to the management of the use of drugs, and even have to be removed from the shelves in serious cases.

Reproductive toxicity is a very serious issue in the application and management of pesticides, because it affects not only the fate of a newborn, but also the whole family to endure suffering. In the United States, which is recognized as the leader of agricultural science and technology in the world, California is the largest agricultural state, and California is also the first state in the United States to legislate to regulate the reproductive toxicity of pesticides. As early as 1984, it passed the Neonatal defect Prevention Act (SB950), mainly to prevent reproductive toxicity and teratogenicity caused by pesticides.

The understanding of the mechanism of reproductive toxicity is a very important topic in the field of life science research and development since the new century. Reproductive toxicity mainly affects the process of embryonic development in female animals and testicular function and sperm development in male animals. In recent years, specific drugs have led to the elucidation of the molecular basis of reproductive toxicity-related physiological / biochemical and gene expression. What's more, people do not dare to take the management of such side effects of drug use lightly. (the article is not finished to be continued)

─, a public policy network participation platform, expressed its views on the use of "killing grass" in fallen leaves of red bean.

(to read a series of reports on the controversial use of herbicide for red bean defoliant, please click here.)