this was initially a small portion of the plant’s operations. In the 1960s, UCC expanded operations, including construction of facilities to produce carbamates and to allow for production of new synthetic intermediates for other companies (Woomer, 2000). Rhône-Poulenc purchased UCC’s agricultural division, including the Institute site, in 1986. In 2000, Aventis (formed by a merger of Rhône-Poulenc and AgrEvo) took over management of the facility. Finally, Bayer CropScience acquired the facility in 2002 (CSB, 2011). Bayer CropScience is a global provider of insecticides, herbicides, and fungicides. Independently operated within Bayer, AG, Bayer CropScience is headquartered in Germany. The company employs about 20,700 workers in over 120 countries (Bayer CropScience, 2011c). The U.S. headquarters are in Research Triangle Park, North Carolina.
In 2008, the facility hosted seven tenants. Bayer CropScience owned and operated 9 of the 16 production units on the site. Two production units, owned by Adisseo and FMC Corporation, were also operated by Bayer. The remaining units were owned and operated by Dow Chemical, Catalyst Refiners, Reagent Chemical, and Praxair, respectively. Bayer employed approximately 85 percent of the 645 workers employed at the facility (CSB, 2011).
HISTORY OF CARBAMATE INSECTICIDE MANUFACTURING
The focus of production at the Bayer plant in 2008 was on carbamate pesticides, which have been shown to be effective against a variety of pests. The general structure of carbamate pesticides is R1NHCOOR2, where R represents alkyl or aryl groups. The facility in Institute manufactured a number of different carbamates over the years. The processes for manufacturing these materials have changed over time, some of which have implications for process safety. What follows here is a description of some of the major changes at the facility, and Appendix B contains a detailed timeline of modifications. The major carbamate products are summarized in Table 3.1.
Carbamate pesticide production in Institute began in the 1960s with carbaryl. Carbaryl is a broad-spectrum pesticide and is used in a variety of commercial and residential settings for control of pests such as beetles, crickets, fleas, ticks, and moths (U.S. EPA, 2004). Production of MIC also began during that decade, although at that time it was only manufactured for use at other facilities and for sale to other companies rather than for use onsite. That changed in 1976 with the production of aldicarb in Institute. Aldicarb had previously been produced in Woodbine, Georgia, and although final formulation and packaging of the material continued at that site, synthesis of the pesticide was moved to Institute. While sharing basic carbamate chemistry with carbaryl, for reasons that are discussed in Chapter 5, production of aldicarb was carried out by a chemical pathway using phosgene and MIC. Aldicarb is primarily used to control nematodes and sucking insects in crops such as cotton, beans, and peanuts (U.S. EPA, 2010). The method for production of carbaryl was changed in 1978 from one that used naphthyl-