Tecnazene water pollution

The Advisory Committee on Pesticides (ACP) has reviewed the sprout suppressant tecnazene used on potatoes. The recommendations, which were accepted by government, allow for the continued use of tecnazene despite concerns over water pollution. As a result of the review, the maximum residues limit in potatoes has been raised to 10mg/kg from 5 mg/kg.
    The ACP requested that a review of water pollution from residues of potato sprout suppressant used on potatoes be conducted by the Pesticides Safety Directorate, an executive agency of the Ministry of Agriculture. Previous surveys in the late 1980s measured residues in effluent and stream water from around potato washing plants. Mean levels of 13µg/l of tecnazene and  22µg/l of TAC (a breakdown product) were detected. There was also evidence that illegal washing occurred outside the normal period. One site sampled showed detectable levels of tecnazene even when the plant was not operating.
    Further data required includes: formulation data; residue stability and metabolism data; a study on environmental fate and behaviour and operator exposure data. The ACP also requested some general information be submitted about potato washing plants in the UK such as their number and location. Tecnazene is currently being reviewed as part of the Europe-wide EU programme.

Evaluation on: Review of Tecnazene, No 127, April 1995, MAFF, 160pp.

[This article first appeared in Pesticides News No. 28, June 1995, page 26]