Proper Management of PRTR Substances
Chemical substances that are used in the research and development and production of pharmaceutical products include some substances subject to the PRTR system that could have an impact on the environment. The amount of these substances handled, released into the environment and transferred as waste need to be understood and properly managed. Therefore, in addition to using our unique reagent management system to monitor the usage of reagents by the Eisai Group in Japan, we are also striving to reduce our usage of PRTR substances and control their release into the environment. In the event that the amount of PRTR substances used exceeds the designated limit, we surely report this matter to the relevant prefectural governments without delay.
The amount of chemical substances used in the manufacturing process depends largely on the volume of pharmaceutical products produced. However, to maintain the quality of active pharmaceutical ingredients, it is not easy to change manufacturing conditions after entering the commercial production phase. Therefore, from the perspective of green sustainable chemistry,* we are working from the research and development stage to reduce the amount of chemical substances used, utilize alternative solvents, and develop synthetic methods that reduce the amount of substances used. In addition, we actively promote the reuse of organic solvents and incorporate various means into the manufacturing processes to minimize their release into the atmosphere.
The total amount of PRTR substances handled by the Eisai Group in Japan during fiscal 2020 increased 43.9% from the previous fiscal year, coming to 380 tons. This increase was due to large growth in the amount of production of anti-cancer drugs and drugs in the neurology area. As a result, seven substances were reported to the authorities as in the previous year.
＊ Chemical technology that considers the environment and supports the sustainable development of society.
Volatile Organic Compounds (VOCs) Release Control
VOCs, such as ethyl acetate, acetone and methanol, are highly volatile and turn into gas in the atmosphere, and as is the case with NOx discharged from production plants, cause the generation of photochemical oxidants. From the viewpoint of preventing air pollution, these substances need to be controlled to reduce their release into the atmosphere. To this end, main production plants and research laboratories of the Eisai Group in Japan implement the same level of efforts as for PRTR substances to reduce the usage of VOCs and stipulate equipment operation procedures to minimize their release during production or research processes.
The graph below shows chronological changes in the amount of VOCs handled and released into the atmosphere of 55 substances (taken from the Ministry of the Environment’s list of 100 major VOCs, excluding PRTR substances) that are handled and released by plants and research laboratories of the Eisai Group in Japan. In fiscal 2020, total amount of VOCs used by the domestic Eisai Group was 1,168 tons, an increase of 3.6% compared with the previous fiscal year, due to an increase of production at the Kashima Plant. As a result of countermeasures taken at plants and research laboratories, the amount of VOCs released into the atmosphere was minimized to 28 tons, which is 2.4% of the amount of VOCs handled.
Proper Management of Polychlorinated Biphenyl (PCB) Waste
We store PCB waste properly in enclosures with locks and warning signs and with measures taken to prevent vaporization, dispersion, and leakage. In the Eisai Group in Japan, although one transformer and a set of PCT-containing paints were stored at the Kawashima Plant, disposal of these wastes was completed in fiscal 2020 in accordance with the Law Concerning Special Measures Against PCB Waste. As a result, the disposal of PCB waste by the Eisai Group in Japan has been completed. The notification of completion of processing from the Kawashima Plant was submitted to Gifu Prefecture without delay.
Management of Fluorocarbons
The Eisai Group in Japan is systematically disposing of and replacing fluorocarbon-based equipment with equipment that uses hydrofluorocarbons (HFC) and non-fluorocarbons (NON), which do not have ozone-depleting effects. Since fluorocarbons have a strong greenhouse gas effect, we conduct regular inspections to prevent leakage accidents. In the unlikely event of a leakage, we immediately share information and work to prevent recurrence.
Whenever a piece of equipment is removed, we ensure that all fluorocarbons are collected, destroyed and disposed of, and ensure that process certificate is received from fluorocarbon recovery firm. The amount of fluorocarbons leaked by Eisai Co., Ltd. in fiscal 2020, calculated based on the Act on Controlling Emissions of Fluorocarbons, is equivalent to 553 tons of CO2, which is lower than the threshold to be reported to the Ministry of Health, Labour and Welfare.