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9-Misc: Danish researchers found glyphosate leaching intogroundwater

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                                  PART I
-------------------------------- GENET-news -------------------------------

TITLE:  Poisonous Spray [Roundup] on a Course Towards Drinking Water
SOURCE: Politken, Denmark, by Anders Legarth Schmidt
        english translation sent by NGIN, UK
DATE:   May 10, 2003

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Poisonous Spray [Roundup] on a Course Towards Drinking Water

Denmark's most popular herbicide Roundup is polluting the underground
water far more than previously thought. Agriculture uses yearly 800 tons
of active glyphosate in herbicide. The Environment Minister is looking at
taking steps to address this. The Danish drinking water resources are
under attack from an unexpected quarter. The chemical glyphosate that is
in the popular herbicides Roundup and Touchdown is against all
expectations sieving down through the soil and polluting the ground water
at a rate of five times more than the allowed level for drinking water.
This has been shown from tests done by the Denmark and Greenland
Geological Research Institution [Danmark og Gronlands Geologiske
Undersogelse (GEUS), HM/GENET] in an as yet unpublished article.

Believed Bacteria broke down glyphosate

"When we spray glyphosate on the fields by the rules it has been shown
that it is washed down into the upper ground water with a concentration
of 0.54 micrograms per litre. This is very surprising, because we had
previously believed that bacteria in the soil broke down the glyphosate
before it reached the ground water." It is the Environment Ministry that
has given permission to use glyphosate - based on the producers
[Monsanto's] own research.

Used against Twitch and Thistles

Farmers spray glyphosate on their fields after the harvest to keep the
soil free of twitch and thistles. It had been earlier found in wells in
Roskilde and Storstroms regions as well as the Copenhagen district
council area. Critics say glyphosate causes cancer, while its defenders
call it a wonder herbicide. Professor Mogens Henze the head of the
Institute for Environment and Resources at Denmark's Technical
University, says that the consequence of the new knowledge is that water
works in five to ten years will need to clean the water before Danes can
drink it. "The results show that glyphosate is polluting our drinking
water. And unfortunately we have only seen the tip of the iceberg,
because glyphosate and many other spray chemicals are on their way
through the soil at this point in time. Politicians need to look at
agriculture in relation to clean drinking water and decide what it is
they are going to do." says Mogens Henze, who isn't blaming the farmers
who use something that the authorities have allowed.

Use Doubled

Statistics from the Environment Ministry show that the use of glyphosate
has doubled in the last five years. In 2001 800 tons was used and that
made up a quarter of farmers total use of pesticides. This shows that
glyphosate is the most used herbicide by farmers. As a result of the new
research from DGGRI the Environment Minister Hans Christian Schmidt is
currently thinking about doing something about the use of glyphosate on
Danish fields. "It is simply not acceptable that this stuff is turning up
in our groundwater in such a concentration so high over the acceptable
level. If this is the case then we must react quickly" says the
Environment Minister, who is awaiting a report from the Environment Ministry.

                                  PART II
-------------------------------- GENET-news -------------------------------

TITLE:  Danish glyphosate restrictions draw protests
SOURCE: Environment Daily no. 1457
DATE:   Jun 5, 2003

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Danish glyphosate restrictions draw protests

Danish environment minister Hans Christian Schmidt has announced
unprecedented restrictions on glyphosate, the country's and Europe's most
widely used herbicide. The action follows publication of data showing the
chemical's presence in groundwater, from which Denmark obtains most of
its drinking water. Although concentrations in drinking water did not
exceed permissible limits, it was "worrying" that unacceptable quantities
of glyphosate and its breakdown product AMPA might build up via drainage
in the uppermost levels of groundwater, Mr Schmidt said. "Danes should be
able to put the coffee on in the morning without worrying about
pesticides", he added. From 15 September, autumn spraying of glyphosates
will be banned on sites "where leaching is extensive because of heavy
rain". There are a number of exceptions to the new restrictions, which
are subject to revision after an interim consultation period. In a joint
response, Cheminova, Syngenta and Monsanto, which manufacture or sell
glyphosate in Denmark, condemned the government's move as "unacceptable"
for the producers or Danish farmers. Glyphosate could only be identified
as a threat by ignoring "scientific findings and knowledge", they said.
According to the firms, the restrictions appeared to be based on finding
of glyphosate at one metre's depth in the soil. This "can hardly - and
only with the most narrow political intentions - be regarded as
groundwater, and certainly not as drinking water", they complained.

The Danish row will reignite a gathering EU debate on the sustainable
pesticides use being coordinated by the European Commission, which is due
to issue firm proposals for a strategy next year
(ED 04/07/02

European NGOs and some MEPs are campaigning for a halving in pesticide
usage over ten years
(ED 28/03/03

Danish EPA, tel: +45 32 66 01 00, and press release
Cheminova, Syngenta and Monsanto statement

                                  PART III
-------------------------------- GENET-news -------------------------------

TITLE:  The Danish Pesticide Leaching Assessment Programme 
        Monitoring results May 1999 - June 2002
SOURCE: Danmark og Gronlands Geologiske Undersogelse (GEUS)
DATE:   Jun 2003

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The Danish Pesticide Leaching Assessment Programme (PLAP)
Varslingssystem for udvaskning af pesticider til grundvand (VAP)

Monitoring results May 1999 - June 2002
Third report
Jeanne Kjr, Marlene Ullum, Preben Olsen, Pia Sjelborg, Arne Helweg,
Betty Bgel Mogensen, Finn Plauborg, Ruth Grant, Inge S. Fomsgaard and
Walter Brsch.

Geological Survey of Denmark and Greenland, Ministry of the Environment
Danish Institute of Agricultural Sciences, Ministry of Food, Agriculture
and Fisheries
National Environmental Research Institute, Ministry of the Environment

Editor : Jeanne Kjr
Cover: Peter Moors
Layout and graphic production: Authors and Lasse Gudmundsson
Printed: June 2003
Price: DKK 200
ISBN 87-7871-115-0

Available from:
Geological Survey of Denmark and Greenland
Oster Voldgade 10
DK-1350 Copenhagen

Phone: +45 3814 2000
Fax: +45 3814 2050


The report is also available at



In 1998, the Danish Government initiated the Danish Pesticide Leaching
Assessment Programme (PLAP), an intensive monitoring programme aimed at
evaluating the leaching risk of pesticides under field conditions. The
first phase of the programme from 1998 to 2001 was funded by the Danish
Government, while a two-year prolongation from 2002 to 2003 was funded by
the Ministry of the Environment and the Ministry of Food, Agriculture and

The work was conducted by the Geological Survey of Denmark and Greenland
(GEUS), the Danish Institute of Agricultural Sciences (DIAS) and the
National Environmental Research Institute (NERI) under the direction of a
management group comprising Jeanne Kjr (GEUS), Marlene Ullum (GEUS),
Svend Elsnab Olesen (DIAS), Arne Helweg (DIAS), Ruth Grant (NERI), Betty
Bgel Mogensen (NERI), Christian Ammitse (Danish Environmental
Protection Agency) and Christian Deibjerg Hansen (Danish Environmental
Protection Agency).

This report presents the results for the period May 1999-June 2002.
Preliminary results covering part of the period (May 1999-June 2001) have
been reported previously (Kjr et al. , 2002). The present report should
therefore be seen as a continuation of that report, with the main focus
on the monitoring period July 2001-June 2002.

The report was prepared jointly by Jeanne Kjr (GEUS), Marlene Ullum
(GEUS), Preben Olsen (DIAS), Pia Sjelborg (DIAS), Arne Helweg (DIAS),
Betty Bgel Mogensen (NERI), Finn Plauborg (DIAS), Ruth Grant (NERI),
Inge S. Fomsgaard (DIAS) and Walter Brsch (GEUS). While all authors
contributed to the whole report, the aspects for which each author was
mainly responsible are as follows:
- Pesticide and bromide leaching: Jeanne Kjr, Preben Olsen and Walter Brsch
- Soil water dynamics and water balances: Marlene Ullum, Finn Plauborg
and Ruth Grant
- Degradation and sorption parameters: Pia Sjelborg, Inge S. Fomsgaard
and Arne Helweg * Pesticide analysis quality assurance: Betty Bgel Mogensen.

Jeanne Kjr
June 2003



In 1998, the Danish Government initiated the Pesticide Leaching
Assessment Programme (PLAP), an intensive monitoring programme aimed at
evaluating the leaching risk of pesticides under field conditions. The
objective of the PLAP is to improve the scientific foundation for
decision making in the Danish registration procedures for pesticides. The
specific aim is to analyse whether pesticides applied in accordance with
current regulations leach to the groundwater at levels exceeding the
maximum allowable concentration of 0.1 g/l.

The PLAP includes evaluation of the leaching risk of 27 pesticides at six
agricultural sites (ranging from 1.1 to 2.4 ha) representing a wide range
of Danish soil and climate conditions. The pesticides were all applied at
the maximum permitted rate. Bromide tracer was applied early in the
monitoring period and bromide and pesticide concentrations are measured
monthly in both the unsaturated and the saturated zones, and weekly in
the drainage water. This report presents the monitoring results for the
six agricultural sites during the monitoring period May 1999-June 2002.
The report is preliminary as the monitoring period is too short to fully
evaluate the leaching risk of all applied pesticides. A more complete
evaluation integrating the monitoring data with both sorption and
degradation studies and modelling of pesticide transport will be made
once a more comprehensive data set covering the entire leaching period of
more pesticides becomes available. The results hitherto obtained
preliminary findings are that:

- Nearly half of the applied pesticides (11 of 27) did not leach during
the current monitoring period.

- The monitoring data indicate unacceptable leaching of two of the
applied pesticides or their degradation products. Thus glyphosate and its
degradation product AMPA and two degradation products of metribuzin
leached from the root zone (1 m b.g.s.) in average concentrations
exceeding the maximum allowable concentration of 0.1 g/l.

- At the two sandy sites, previous application of pesticides has caused
marked ground water contamination with degradation products of
metribuzin. These appear to be relatively stable, and both leached
throughout the entire monitoring period, thus indicating continuation of
leaching as long as three years after application. There was evidence
that the degradation products may persist in the groundwater several
years after application.

- Finally, the monitoring data indicate leaching of a further 14
pesticides. The levels of leaching hitherto detected were not
unacceptable, however. Although the concentration in several samples
exceeded 0.1 g/l, the average concentration did not.

The monitoring data were supported by hydrological modelling (MACRO
version 4.2) providing an overall water balance for each of the six
sites. The model was parameterized using measured data or literature/
default values, but has not yet been calibrated except for the sandy
sites Tylstrup and Jyndevad. The uncalibrated models performed
surprisingly well when comparing simulated and observed time series for
groundwater table, soil water content and drainage flow.

Sorption and degradation parameters were determined on various
combinations of pesticides and soil types representative of the PLAP. The
results suggest that:

- Microbial activity, sorption and degradation rates are low, as is
generally the case in subsoil.

- Both degradation rates and sorption differed markedly between soils,
thus stressing the importance of having site-specific parameters when
modelling the leaching of pesticides.

- The degradation rates were in some cases better described by a two-
compartment 1 st + 1 st order model than by the usual 1 st order model.
Degradation often encompasses an initial fast degradation rate with a
short half-life followed by slower degradation rates with longer half-
lives. An error is thus introduced if the simple 1 st order half-life is
used in the evaluation of pesticide persistence. Further analysis of the
significance of the introduced error for risk assessment of pesticide
leaching is thus required.

The quality of the pesticide analyses was evaluated continuously using an
intensive quality assurance (QA) system. This consisted of internal
control samples prepared by the analysis laboratory as part of their
standard method of analysis and both blank and spiked samples prepared in
the field and analysed in the laboratory together with the routine
samples. The overall quality of the pesticide analysis was considered

- Reproducibility of the pesticide analyses was good, with standard
deviation generally being in the range 0.003-0.025 g/l.

- Reproducibility of the degradation products was slightly poorer than
that of the mother compounds, standard deviation being 0.004-0.029g/l.

- Recovery was generally good (> 70%) in the case of spiked samples.
Exceptions are fenpropimorph, desmedipham, glyphosate, phenmedipham and
pirimicarb at single sites.

- Variation in recovery of the same compound in spiked samples from all
field sites indi cate uncertainties in analysis caused by differences in
matrix composition.

- Contamination of samples rarely occurred during collection, storage and


European NGO Network on Genetic Engineering

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