Memorandum submitted by the Ministry of
Agriculture, Fisheries and Food (B 10)
1. ISSUE
1.1 The Government has required the holders
of marketing authorisations for organophosphorus (OP) sheep dips
to withdraw their products from the market by 31 January pending
the introduction of new containers designed to minimise the risk
of operator exposure to concentrated dip.
2. BACKGROUND
2.1 OP dips for use against sheep scab were
introduced in the 1980s, replacing organochlorine dips, which
were persistent in the environment. They are effective against
serious sheep ectoparasites, including the scab mite, blowfly,
ticks, keds and lice. OPs are toxic chemicals and must be handled
with care. They are absorbed through the skin and measures must
be taken to prevent exposure.
2.2 Advice on sheep dipping is provided
in booklet, AS29(rev2), in the Agriculture Safety series, issued
jointly by the Health and Safety Executive (HSE), the Veterinary
Medicines Directorate (VMD), the Environment Agency and the Scottish
Environment Protection Agency (SEPA). The booklet has been sent
free to all registered sheep farmers in Great Britain. It sets
out a hierarchy of safety measures to be taken when dipping, including
properly designed and sited dipping baths, engineering controls
(eg screens and splash boards), and personal protective equipment
(PPE).
2.3 Warnings and advice are included on
the labels of containers of sheep dips. Proposals for simplified,
more easily understandable labels are under preparation and will
be widely circulated for comment.
2.4 An interdepartmental high-level group
of officials ("`the official group'") was set up in
December 1997 to monitor information sharing on OPs and to draw
together scientific evidence. Its report—"Official
Group on OPs—Report to Ministers"—was published
on 25 June 1998.
3. RESEARCH AND
COMMITTEES' ADVICE
3.1 A report of a three-year epidemiological
study by the Institute of Occupational Medicine (IOM), published
in July 1999, identified the handling of concentrated OP dip as
the main source of potential exposure. It suggested that exposure
to concentrates was associated with an increased likelihood of
ill-health in the groups of subjects studied. The report was referred
to the Department of Health's Committee on Toxicity of Chemicals
in Food, Consumer Products and the Environment (COT), which had
been asked in 1998 to review the evidence of possible ill-health
effects of OPs and to advise on whether prolonged or repeated
low-level exposure could cause chronic ill-health effects. The
IOM's report was also referred to the Veterinary Products Committee
(VPC) and the Advisory Committee on Pesticides (ACP) for urgent
advice on whether its findings affected their earlier advice on
the safety of OPs and whether further measures were necessary
in advance of the completion of the COT's review.
3.2 In an interim report, also published
in July, the VPC advised that marketing authorisation holders
should be asked to submit practicable plans to improve and standardise
the design of sheep dip containers, with the objective of minimising
operator contact with OP concentrate. Plans were to be submitted
within three months and if they were not, action would begin to
revoke marketing authorisations.
3.3 The COT's report, published in November,
concluded that the balance of evidence did not support the hypothesis
that prolonged or repeated low-level exposure to OPs caused peripheral
neuropathy or clinically significant neuropsychological effects.
It indicated that, if such effects did occur, they must be relatively
uncommon. There remained a question, however, over whether there
might be a small group of individuals particularly susceptible
to OPs.
4. FURTHER
ADVICE FROM
THE VPC
4.1 The VPC and other regulatory committees
were asked to consider the regulatory implications of the COT's
report and all advised against a general withdrawal of OPs from
the market. The VPC had also considered plans submitted by the
marketing auhorisation holders for changes to concentrate containers.
One company was able to demonstrate satisfactory plans for long-term
improvement and a short-term, interim solution. None of the other
plans was fully satisfactory. Time would be needed to introduce
even the interim solution and the VPC therefore advised that all
OP sheep dips should be withdrawn from the market pending the
introduction of new containers which would minimise operator exposure.
5. THE ANNOUNCEMENT
5.1 The Government's response to the committees'
reports was announced to Parliament on 20 December. Companies
could not be informed before Parliament but were informed of the
withdrawal by letter immediately after the announcement, and a
News Release was also issued. Marketing authorisations were immediately
suspended pending the introduction of new containers. This meant
that no OP sheep dips could legally be sold or used from that
date.
5.2 All companies co-operated. Sales were
stopped immediately and marketing authorisation holders took action
to comply with the requirement to withdraw products from the market
by 31 January. Withdrawing products from the sales chain is straightforward
but retrieving products from farms presents greater difficulties.
6. EFFECT ON
SHEEP WELFARE
6.1 It will take time to introduce new containers
of concentrated dip. The interim solution proposed by one company
could be introduced relatively quickly but it is possible that
there will be no OP dip available for the Spring dipping season.
There are, however, other products available (synthetic pyrethroid
(SP) dips and injectables) for the control of ectoparasites including
sheep scab. Pour-on products are also available for parasites
other than scab.
7. FURTHER WORK
7.1 The Government announced a four-point
plan for further work arising from the committees' report. This
includes measures to promote best practice in sheep dipping, including
improvements to labelling, targeted inspections by Health and
Safety inspectors, and the development of a research programme
to take forward the research recommendations of the COT and regulatory
committees.
8. SUMMARY
8.1 Following a report from the Institute
of Occupational Medicine, the VPC advised that marketing authorisation
holders for OP sheep dips should submit plans for improvements
to the containers of concentrated dip. Plans were submitted within
the three month deadline but only one was satisfactory. Even the
satisfactory solution would take time to introduce and the VPC
advised that all OP sheep dips should be removed from the market
pending the introduction of improved containers.
8.2 The Government could not delay action
in the light of the VPC's advice and companies were required to
withdraw products from market by 31 January.
8.3 OP sheep dip products will be permitted
to return to the market once satisfactory improved containers,
designed to minimise the risk of operator exposure, have been
introduced.
8.4 Although a satisfactory interim solution
is being developed by one company, it is possible that there will
be no OP dips available in time for the Spring dipping season.
There are, however, alternative products available.
15 February 2000
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