We have looked at all the governments published residue results between Jan 2000 and June 2005, and summarised what they tell us about the pesticide residues in potatoes.

Potatoes have been tested on nine occasions since the beginning of 2000. A further survey was conducted at the end of 2005 and the next surveys will be conducted in the second and 4th quarters of 2006.

The total number of samples that have been tested is 982, which includes 36 organic samples (Each sample is at least 10 potatoes weighing at least 1 kg).

Which pesticides turn up on potatoes?
The five most commonly reported pesticides (with approximate percentages* of non-organic survey samples reported to contain them):

1	Chlorpropham	24.5%
2	Maleic hydrazide	13.7%
3	Oxadixyl	5.8%
4	Tecnazene	2.6%
5	Imazalil	2.0%

*Not all the individual pesticides were tested for in all the samples, and so the percentages may underestimate their occurrence.

Find out more about the health and environmental effects of these pesticides

There were eight different pesticides found at least once over the nine surveys

How frequently do residues occur on potatoes?
38% (377) of all samples contained measurable residues, including 1 organic sample.

11% (106) of samples had more than one pesticide residue. The highest number of pesticides found in one sample was four.  The average number of pesticides found in non-organic samples was 0.52.  Taking into account only those samples that do contain residues, the average number of pesticides found was 1.3.

How often are residues greater than legal limits?
Seven samples had a residue that was above the legal limit.

 Residues greater than the legal limit reported in potatoes between 2000 and June 2005

Report	Country of origin/type of potato	Pesticide	Residue found, mg/kg	Legal limit (MRL), mg/kg
2001Q4	UK/new	Aldicarb	0.6	0.5
2001Q4	UK/new	Maleic hydrazide	5.8	1
2001Q4	France/new	Maleic hydrazide	25	1
2002Q2	UK/maincrop	Dithiocarbamates	0.06	0.05
2002Q2	UK/maincrop	Dithiocarbamates	0.07	0.05
2002Q2	UK/new	Imazalil	0.07	0.02
2003Q2	UK/maincrop	Tecnazene	1.3	0.05