Other natural organohalogens

Over 4,000 chlorinated and other halogenated compounds are produced naturally, dispelling the widespread notion that these chemicals are only of man-made origin.

The synthetic chlorine-containing chemicals DDT, PCBs (polychlorinated biphenyls), dioxins, and several others are known by the public as persistent and toxic man-made environmental pollutants.
Less well known - even to many scientists - is that nature has been producing similar, and in some cases, identical halogenated organic compounds since the beginning of life on earth.

The sheer number and chemical diversity of these naturally-occurring organochlorines, organobromines, organoiodines, and organofluorines are truly astounding. These natural halogen-containing chemicals are produced by bacteria, fungi, plants, marine organisms, insects, and higher animals including humans.

The extraordinary compounds are also formed abiogenically, as in volcanoes, forest fires, and other geothermal events. In some instances, these natural organohalogens are the same chemicals that man synthesises for industrial use. Some of the quantities of these natural chemicals far exceed the quantities emitted by man.

Read more about natural organohalogens in our Science Dossier.

Prof. Gordon W. Gribble and his chlorine research

Prof. Gordon W. Gribble is a Professor of Chemistry and former chairman of the Department of Chemistry at Dartmouth College, Hanover, New Hampshire, USA. His research interests include the synthesis and isolation of biologically active natural products, heterocyclic chemistry, synthetic methodology, and environmental organic chemistry. He has published 170 papers in these areas.

For the past 25 years Professor Gribble has had a special research interest in naturally-occurring chemicals, particularly those containing chlorine and other halogens.

Read more about Dr. Gordon W. Gribble and his research on dartmouth.edu.