Repealing peeling advice

The UK government is considering changing its advice for consumers to peel fresh fruit and vegetables in order to reduce exposure to pesticide residues. Sandra Bell explains why public interest groups are not convinced by the arguments from scientific agencies that help formulate official policy.

FOE poster

If we are to believe recent statements of the Food Standards Agency (FSA) and the Advisory Committee on Pesticides (ACP) [that advises on pesticide safety] we should all be celebrating the progress in reducing pesticide residues which means that advice to peel fruit and vegetables is no longer needed. However, Friends of the Earth (FOE) is not convinced. Having looked at the evidence on which the FSA’s statement is based it is clearly driven by politics and not by scientific assessment. Other public interest groups share FOE concerns including PAN UK and the Consumers Association. 
    FOE’s view is that the government and retailers should be aiming for zero residues in fruit and vegetables so that they can be eaten with confidence that they do not contain toxic residues. However, until we reach that goal it is important that consumers have access to information about what pesticides do occur in their food and to practical advice on how to reduce their exposure. Peeling will not remove all residues (particularly systemic pesticides which go more than skin deep) but it is a practical way to reduce them, and is useful advice to consumers, particularly those who cannot afford or do not have access to organic food. Interestingly the Environmental Protection Agency in the US still advises consumers to ‘peel fruits and vegetables when possible to reduce dirt, bacteria and pesticides’. So what has prompted the FSA’s desire to get rid of the advice in the UK?

Background
The advice, issued by the Chief Medical Officer, that peeling fruit and vegetables ‘is a sensible additional precaution when preparing fruit and vegetables for small children has been given out to the public since 1997 in response to queries about pesticide residues. The advice was originally issued due to concerns about incidences of high levels of pesticide residues in some fruit and vegetables.
    In March 2000 Health Minister Gisela Stuart confirmed that the advice ‘remains relevant and is used by government departments in responding to inquiries about pesticide residues in food’.(1) Yet little more than one year later, in May 2001 Health Minister, Yvette Cooper stated that the FSA was now reviewing the need for the advice since the ‘situation with pesticides has moved on and many of the pesticides of particular concern have been withdrawn or are undergoing review’.(2)
    Yvette Cooper’s statement was prompted by a question about whether the peeling advice would be passed on to schools in receipt of free fruit under the Government’s National School Fruit Scheme. It would not do much for the Department of Health’s publicity if schools had to be issued with peeling instructions with their free fruit in order to reduce the dose of pesticides the children were to take in. The FSA’s paper to the ACP in October 2001 confirmed its concerns in this respect when the FSA stated that it could be implied from the advice that ‘only organic food should be supplied to the National School Fruit Scheme’ because non-organic fruit or vegetables would have to be peeled to make them safe(3).
    The FSA then sought the advice of the ACP to give scientific credibility to its line on peeling. The ACP made its decision in March 2002 after considering two papers on pesticide residues from the Pesticide Safety Directorate (an executive agency of the Department for Environment, Food and Rural Affairs that provides the secretariat for the ACP). The ACP recommended that the situation with residues had improved sufficiently for the advice to be revoked.

Pesticide residues – what has changed?
FOE believes that the situation with residues has not improved sufficiently since 1997 to justify withdrawing the advice. The FSA’s paper refers to the review and revocation of organophosphate (OP) and carbamate pesticides since the advice was issued in 1997. However several OP and carbamate pesticides are still approved for use on fruit and vegetable crops in the UK, and even if all these approvals were revoked OP and carbamate pesticides will continue to appear as residues in imported food. 
    In fact the incidence of residues is a more important factor in assessing exposure to pesticides than product approvals. Government data show that in 2000 about three quarters of apples sampled contained pesticide residues (74%) and that 81% of pears contained residues. Both of these fruits will regularly be provided to schools under the National School Fruit Scheme. The residues found include OP pesticides. For example chlorpyrifos was one of the most commonly found residues in samples of apples tested between January and December 2000. Chlorpyrifos was found in 35% of the apple samples(4). In the US concern about children’s exposure to chlorpyrifos led to severe restrictions on its use on food commonly eaten by children (for example, use on apples restricted to pre-bloom applications only). Research has linked exposure to chlorpyrifos with brain damage in young rats(5).

Variability still an issue 
Both the FSA and the ACP have claimed that the issue of variability (that is, very high levels of pesticides in individual fruits or vegetables) has now been addressed. However, high levels of residues continue to occur in composite sampling, for example: 

• Among the 50 carrot samples tested in 2000 one contained levels of the organophosphate pesticide, chlorfenvinphos which were so high that the Pesticide Residue Committee (PRC) concluded that ‘if the carrots were eaten unpeeled then safety margins would be eroded’6.

ACP plays down exceedences of safety levels
FOE obtained the two Pesticide Safety Directorate papers which were considered by the ACP to inform their decision. These looked at recent residues in fruit and vegetables and modelled exposure based on ‘worst case’ scenarios (ie high level consumption and high residue levels). 
    The first of the two papers(7) looked at residues in apples and pears. In 1999 the Working Party on Pesticides Residues (which preceded the PRC) said that levels of chlormequat in pears were high enough to give a toddler a ‘mild stomach upset’. The PSD paper confirms that the Acute Reference Dose for chlormequat would still have been exceeded by toddlers eating imported pears in 2000. However, the PSD seeks to avoid unfortunate conclusions by pointing to the fact that the acute reference dose is based on rabbits and dogs and that monkeys are less sensitive: ‘if humans are more similar to monkeys in this respect then there may be a considerable margin of safety built into the acute reference dose’. This begs the question as to why PSD rely on rabbit and dog data for this information. Or is it a case of trying to diffuse an unfavourable result.
    The second PSD paper(8) looked at residues in a range of fruit and vegetables. It finds that significant exceedences of the Acute Reference Dose for toddlers are likely for a range of pesticides (see Table 1), in some cases over 1000% of the acute reference dose. Pesticides included organophosphates and pesticides which are known to interfere with the hormone system.
    Incredibly, the ACP stated that it was reassured by these results. In our view these two papers raise more questions and concerns than they provide reassurance. 

Multiple residues
Although the PSD papers claimed to look at ‘worst case’ scenarios, neither considered the presence of multiple residues in fruit and vegetables, or exposure to pesticides from other routes, for example, in the home or school grounds which could be a significant source of exposure for children. Over a third of apples tested between October and December 2000 contained residues of more than one pesticide. The FSA has acknowledged that not enough is known about the health effects of exposure to multiple residues and for this reason requested the Committee on Toxicity of Chemicals in Food, Consumer Products, and the Environment to establish a working group to investigate the potential effects on human health. The draft report from the Committee recommends that the regulatory process should take into account all routes of exposure to pesticides and should address the potential for combined toxic action. The Committee also pointed to the lack of sound data on exposure, particularly from non-dietary sources.

Uncertainties about levels of exposure
Estimates of acute exposure which are used for acute risk assessment rely on data about consumption supplied by the FSA. FOE considers that the assumptions made about consumption of fruit and vegetables for acute exposure are too conservative – a so called ‘high level’ consumer may actually be eating relatively small portions of fruit and vegetables. For example the risk assessment assumes that a toddler (aged 1½ – 4½) will eat only one orange in a day(9). These consumption figures need to be updated, especially in light of the Department of Health’s aim to ensure that by the age of five, children will be eating five portions of fruit and vegetables a day. Given that the review of the peeling advice was prompted by concerns over the National School Scheme surely the PSD and FSA should have looked at exposure levels for children eating their recommended five portions a day.
    Another problem in assessing exposure is the small number of samples of fruit and vegetables monitored for pesticide residues each year. For example, just one sample of carrots in 2000 contained residue levels above safety limits, but only 50 samples were tested. The occurrence of one sample in 50 containing such high levels raises the possibility of many other untested carrot samples containing similar levels. Since we do not know the scale of the problem a precautionary approach in terms of consumer advice is necessary. 
    Although the Department of Health (DoH) has carried out monitoring on fruit being supplied to the National School Fruit Scheme this has been very limited e.g. only 17 apple samples. A high incidence of residues was found but since there were no MRL exceedences the DoH sees no cause for concern, and simply referred to the multiple residues found in apples as ‘not unusual’.

Uncertainties about health effects 
In making its case to the ACP the FSA concentrated on OPs and carbamates and has failed to consider potential health effects of other types of pesticide. For example, since the advice was first issued by the Chief Medical Officer (CMO) in 1997 there has been growing concern about exposure to low levels of pesticides which are known to disrupt the hormone system. This was acknowledged in the Royal Society report on endocrine disrupting chemicals in 2000(10). Babies and young children are particularly vulnerable to exposure to such chemicals because their reproductive system is still developing. The EC has drawn up a list of chemicals for which it considers there is strong evidence of endocrine disrupting effects, including pesticides such as vinclozolin. Data published by the PRC shows that suspected endocrine disrupters, including carbendazim and vinclozolin, are regularly found as residues in fruit and vegetables including apples, pears and kiwi fruit(11). The second PSD paper considered by the ACP revealed that Acute Reference Doses do not even exist for some hormone disrupting pesticides.

Bad science, bad decision
The ACP and FSA made their decisions despite having incomplete information about levels of exposure and in the face of significant uncertainties about the possible effects on human health. There has not been a clear reduction in pesticide residues in fruit and vegetables since the advice to peel was issued. The FSA’s paper indicates that the desire to revoke the advice arose from the potential clash of two government policies. It would embarrass the DoH if its distribution of free fruit had to be accompanied with safety advice to peel it before consumption. This decision must question the integrity of the ACP as a scientific advisory committee and of the FSA as a body set up to protect the consumer.

References
1. House of Commons Hansard Written Answers for 13 March 2000.
2. House of Commons Written Answers for 1 May 2001. 
3. Report ACP 20 to the Advisory Committee on Pesticides, 18 October 2001, Review of the need for Chief Medical Officer’s (CMO) advice on washing and peeling fruit and vegetables.
4. Quarterly report of the Pesticides Residues Committee, October-December 2000.
5. Cohn J and MacPhail RC, 1997, Chlorpyrifos produces selective learning deficits in rats working under a schedule of repeated acquisition and performance, Journal of Pharmacology and experimental Therapeutics, 283: 312-320.
6. Annual Report of the Pesticide Residues Committee 2000.
7. Report to ACP, 16 to the Advisory Committee on Pesticides 29 November 2001, Review of CMO advice to peel fruit and vegetables: residues on apples and pears.
8. Report ACP 10 to the Advisory Committee on Pesticides, 4 March 2002, Consumer Risk Assessments based on PRC monitoring data.
9. Harris CA, Future Developments of Exposure Models to Calculate Potential Intakes of Pesticide Residues by UK Consumers, paper to ACP 6 September 2000.
10. The Royal Society, 2000, Endocrine Disrupting Chemicals.
11. Various Annual Reports of the Pesticide Residue Committee.
12. Report to ACP, Op. cit. 8.

[This article first appeared in Pesticides News No. 56, June 2002, pages 8-9]