Milestones in the Development of China's Pesticide Industry     

By Yin Yimin, China Petroleum and Chemical Planning Institute    

China is an agricultural country with a large population. Food and clothing have always been the primary issues that need to be resolved in the development of China's national economy. Therefore, the pesticide industry has always gotten a lot of attentions from the Chinese government. Up to now, by relying on its own efforts, China can produce more than 300 varieties of pesticide (technical) products and has invented more than 30 varieties of new pesticides that have gotten registration certificates or temporary registration certificates, and invented six pesticides for which intellectual property rights have yet to be requested. Over 6 000 types of pesticide formulations have granted registration certificates or temporary registration certificates in China. Among them, over 250 varieties of pesticides technical and over 3 000 types of pesticide formulations have been put into regular use and can fully meet Chinese farmers' needs and have even been exported in large amounts.

1.  In the initial development stage

In 1950, Sichuan Luzhou Chemical Factory constructed a new dichloro-diphenyl-trichloroethane (DDT) plant and put it into operation in 1951. It was China's first pesticide plant.
   Benzene hexachloride (BHC) developed jointly by North China Institute of Agricultural Science and Shanghai Pesticide Machinery Factory was also put into production in 1951. Later, camphechlor developed by Zhejiang Research Institute of Chemical Industry was put into production in Zhejiang, Fujian and Anhui provinces. In 1957, Tianjin Pesticide Factory established the production plant of China's first organic phosphorus insecticide - parathion.
   In 1962, Prof. Yang Shixian set up the Institute of Element-Organic Chemistry at Nankai University in Tianjin that carried out studies on organic phosphorus chemicals, organic fluorides and organic boron chemicals. By 1966, this institute had developed three types of organophosphorus pesticides like monocrotophos and chloromethiuron, herbicides like diallate, fungicides like phenazine oxide, plant growth regulators like chlormequat chloride and other new pesticides and put them into commercial production.
   During this period, following the industrialization of BHC, Shenyang Research Institute of Chemical Industry carried out a series of research projects, including the improvement of the production process of BHC to achieve continuous production and the development of diphenyl sulfone, tetradifon, parathion, dichlorvos, sodium MCPA, sodium pentachlorophenol, zineb, maneb and kejunling.  
    While starting to synthesize organic pesticides, China launched research work on dusts powder, wettable powder, oil soluble concentrates, emulsifiable concentrates and composite agents and their corresponding processing auxiliary agents.
   Nanjing Zhongshan Chemical Plant was set up in Jiangsu province in the 1950s. It is China's first specialized enterprise to produce chemical auxiliary agents for pesticides. Even today, it is still a major supplier of auxiliary agents for the processing of water-based pesticide formulations.

2.  Bans on the production and use of highly toxic pesticides have promoted the development and upgrade of China's pesticide industry

2.1. Bans on the production of organic mercury in 1972 and its uses in 1973 promoted the development of low-accumulative, chronic fungicides.

In the 1960s and early 1970s, the rice blast and wheat rust in China were prevented and controlled mainly with highly toxic, highly persistent and high-hazard phenyl mercuric acetate and ethyl mercuric chloride. These two fungicides caused many cases of human poisoning. In 1970, the Chinese government began to organize domestic scientists to develop alternatives to mercury-containing fungicides.
    In this period, ethyl garlicin was developed by Mr. Mei Binfu at Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, and Jinggangmycin was developed by Mr. Shen Yichu at the Shanghai Pesticide Research Institute. In 1970, Mr. Zhang Shaoming of Shenyang Research Institute of Chemical Industry synthesized and screened carbendazim. In 1971, the pilot-scale experiment for carbendazim was completed. This fungicide was put into commercial production in 1973.
   Later, other highly effective fungicides, such as thiophanate, thiophanate-methyl, metalaxyl, as well as triadimenol, triadimefon, diniconazole 3 and propiconazole, have also been developed and industrialized. Thus, the ban on the production and use of organic mercuric fungicides has promoted the development and upgrade of China's fungicide industry.

2.2. Banning the production and use of BHC and DDT in 1983 has promoted the development of high-potency low-persistence pesticides

In the 1970s, China's highest output of BHC reached 350 000 tons per year, that of DDT was around 25 000 t/a, and both the production capacity and output of organochlorine pesticides, such as aldrin, dieldrin, sodrin, endrin, heptachlor, chlordane and camphechlor, reached around 400 000 t/a. The rapid growth of organochlorine pesticides was due to their simple and easily available raw materials, short production routine and broad insecticidal spectrums. In addition, all organochlorine pesticides consume chlorine. They consumed more than 35% of chlorine produced in China in that period. At that time, China lacked caustic soda. Chlorine co-generated in the production of caustic soda must be consumed or used to allow increased output of caustic soda.
   However, with the widespread use of BHC and DDT, their cumulative toxicity had caused increasing attention. In 1978, the former Ministry of Chemical Industry of China began to organize domestic scientists to develop organic phosphorus and carbamate pesticides to replace BHC and DDT. On April 1st, 1983 the State Council of China started to prohibit the commercial production and use of BHC and DDT, only allowing Tianjin Chemical Plant and Yangzhou Pesticide Factory to produce DDT exported to Africa for the prevention and control of mosquitoes and permitting Shenyang Chemical Plant and Tianjin Dagu Chemical Plant to produce lindane.
   After the production and use of BHC, DDT and other organochlorine pesticides was banned, China's total output of other pesticides (more than 90% of them were insecticides) was only about 130 000 t/a (100% active ingredients) in 1983, whilst China's pesticide consumption amounted to 210 000 t/a - 230 000 t/a. So there was a large deficit in local supply at that time. Moreover, stopping the operation of a large number of organochlorine pesticide plants had an impact on the consumption of the chlorine from the production of caustic soda and directly inhibited the production of caustic soda.
    So the Chinese government approved the construction of two 5 000 t/a fenitrothion plants in Tianjin and Ningbo, two 1 000 t/a monocrotophos plants in Nantong and Qingdao and the production installations of matched intermediate trimethyl phosphite units. The national government also approved technological renovation or expansion of production capacity of methyl parathion, parathion, methamidophos, malathion, phoxim, trichlorfon, dichlorvos, dimethoate and omethoate.
   The government went on to approve the import of pesticides and their intermediates in thousands of tons annually for several years in a row, costing billions of US dollars. From 1984 to 1986, China's pesticide output reached 180 000 t/a, rapidly solving the issue of replacing BHC and DDT.

2