Zimbabwe grain board phases out methyl bromide fumigant

Zimbabwe's Grain Marketing Board (GMB) has recorded significant progress in phasing out the use of fumigators listed among Ozone Depleting Substances (ODS) in treating stored grain, an official has said.

GMB quality assurance manager and ODS project manager, Patience Mutukwa said there had been a reduction from 14 000 ozone depleting tonnes in 1999 to nearly zero in 2000. She said the reduction had been necessitated by the increase in use of phofaine, an ozone-friendly substance.

"The use of the other alternative contact insecticide and phofaine increased from two tonnes in 1999 to five tonnes in 2000," she said.

She added that the GMB was in the process of equipping its depots with equipment and training personnel to monitor the use of phofaine.

"The use of the chemical needs special knowledge and at the moment, we have trained 40 employers. We are also providing protective equipment, fumigation sheets and gas detectors which will be used to monitor the presence of fumigators, she said.

Mutukwa, however, noted with concern that the alternative, though environmentally friendly, had many disadvantages than its predecessor.

"With the fumigation chemicals it only took two days for total elimination of pests in stored grain of any quantity. But phophaine takes about seven days to treat the same quantity of grain," she said.

Mutukwa added that incorrect use of the new chemical can result in pests developing resistance.

The chemical can be highly flammable if temperature and humidity are not monitored. Zimbabwe, a signatory to the Montreal Protocol, has made relative success in phasing out ODS in agriculture and refrigeration sectors.

New Ziana.