Information on historical and future trends in use and emissions of pe
rsistent organochlorines on a global scale is essential for interpreti
ng present and predicting future environmental concentrations of these
compounds in remote regions. In this study, which is now a recognized
project under the Global Emissions Inventory Activity of the Internat
ional Geosphere Biosphere Program, information on registration status,
trends in regional use/emissions, and mode and time of applications o
f 10 pesticides is being compiled. Results pertaining to four pesticid
es are presented here. The cumulative global usage accounted for (in m
etric tonnes) is 450 000 for toxaphene, 1 500 000 for DDT, 550 000 for
technical HCH, and 720 000 for lindane. The interpolated usage of tox
aphene and DDT was 1 330 000 and 2 600 000 tonnes from 1950 to 1993 an
d 670 000 and 990 000 tonnes from 1970 to 1993. The compounds are stil
l legally used in several countries, and illegal use in other countrie
s has been suggested. International cooperation, changes in legislatio
ns and regulations, and improved record keeping by governments and oth
er bodies are required to restrict usage, as well as to improve the es
timates.