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Air Emissions

We are committed to controlling air emissions from our facilities to reduce local, regional and global environmental impacts.



Air emissions are generated by our manufacturing and research operations, as well as by burning fuel in on-site equipment and fleet vehicles. Our Air Management Standard requires our facilities to quantify and control air emissions to comply with applicable regulations and emission standards.

Many of our pharmaceutical manufacturing processes, cleaning operations and research laboratories require the use of solvents. Evaporation of solvents into the air is the primary source of volatile organic compound (VOC) emissions. In an effort to reduce VOC emissions, reduction in solvent usage has been incorporated as an element of our Green & Sustainable Science program.

Key elements of the program include designing efficient processes that use fewer and less-hazardous solvents and using water-based methods for cleaning our process equipment where they are as effective as solvent-based methods. To reduce emissions from processes where solvents are used, we use pollution-control technologies such as conservation vents, carbon filters, thermal oxidizers, condensers and scrubbers.

Air emissions are also generated by burning fuel in our boilers and power-generation turbines (for heat and energy), and by other combustion processes, such as thermal oxidizers (for treating air emissions) and incinerators (for destroying waste). Our fleet vehicles and aircraft also burn fuel and generate air emissions. These combustion processes result in emissions of carbon dioxide (CO2), nitrogen oxides (NOx), sulfur oxides (SOx) and volatile organic compounds (VOCs). We strive to make our facilities more energy-efficient through our energy-management programs and to improve the fuel efficiency of our fleet vehicles. By making these improvements, we also reduce emissions of CO2, NOx, SOx and VOCs from our operations.


Our NOx emissions increased slightly from 2017 to 2018 due to the need to burn more fuel during the cold winter months and the use of emergency generators at our Puerto Rico facility during an extended power outage caused by Hurricane Maria.

Even though our use of solvents in manufacturing operations has declined over time, our VOC emissions increased from 2017 to 2018 due to the adoption of more-accurate emission-tracking methods.

The decrease in SOx emissions from 2017 to 2018 can be attributed to the use of fuel with a lower sulfur content and our energy-conservation programs.

Emissions of ozone-depleting substances (ODS) are the result of non-routine releases from temperature-control and fire-suppression systems and can vary from year to year.

AIR POLLUTANT EMISSIONS BY TYPE (MT)12014 2015 2016 2017 2018
Nitrogen oxides (NOx)515 494 454 480 494
Sulfur oxides (SOx)49 48 37 37 30
Volatile organic compounds (VOCs)512 455 440 380 404
Ozone-depleting substances (ODS)1.5 0.1 0.7 0.1 0.3
Note: Previously reported data have been restated per our methodology, which includes adding facilities that have been acquired and removing facilities that have been sold as operating sites.
1 Data are estimated using conservative assumptions and factors, not measured or weighed.