Pesticides in a historical perspective

Teckomatorp and hormoslyr arouse Swedish opinion

The use of pesticides in Sweden increased until the mid-1970s, with the greatest increase occurring in the use of herbicides. Opinion against pesticides grew and in Sweden it rapidly came to be directed against the phenoxy acids, chemicals used to control weeds on arable land and scrub in forests. The debate was particularly heated as regards hormoslyr, a phenoxy acid that was often sprayed by planes over logging sites. Knowledge on the importance of correct handling was inadequate, and in the middle of the 1970s the authority responsible recommended that any remaining herbicide should be incinerated or buried. In the mid-1970s it was also revealed that BT Kemi in Teckomatorp, where the herbicides were manufactured, had buried drums of toxic waste on the factory site. Decontamination of the area is still continuing today.

Reports on spread in the environment from 'ordinary' use

For a long time the debate dealt with everything except the place where most of the pesticides were applied, namely arable land. It was assumed that the various compounds were broken down to harmless components after being applied in the field by the farmer. This was not the case. In the middle of the 1980s people began to wonder where these chemicals were going. To the surprise of many, pesticide residues were found in streams and rivers throughout Sweden. The groundwater was also found to be polluted in many areas. Even rainwater proved to contain pesticide residues. To avoid the problems with the persistent, fat-soluble pesticides, more easily degradable but also more water-soluble substances have been developed. This carries an increased risk of pesticides disappearing from arable land and ending up in surface waters or the groundwater instead.