OIA 18-E-0510/docCM-5557437
10 September 2019
Peter Samson
Ema
il: [FYI request #8527 email]
Dear Mr Samson
Thank you for your Official Information Act request to the Department of
Conservation, dated 19 August 2018. You requested the following:
Could you please provide three scientific studies to show that 1080 has no
effect on our waterways and does not contaminate our water. I would like
these scientific studies to include data and tests from areas where 1080 has
been dropped and found in rivers.
I have no difficulty complying with your request and you will find the details of
scientific field studies below. However, for your information, these studies are all
publicly available and therefore the department is not required to release them under
the Official Information Act.
Eason CT, Wright GR, Fitzgerald H. 1992. Sodium monofluoroacetate (1080) water-
residue analysis after large-scale possum control.
New Zealand Journal of Ecology.
16(1):47-49
No 1080 was detected in 36 water samples taken from six streams over a 4-
month period at Waipoua following aerial possum control using 0.08% 1080
Pellets sown at 5 - 6 kg ha-1 in 1990. After the 1990 aerial possum control
operation using 0.08% 1080 pellets at 14 kg ha-1 on Rangitoto Island, 24
water samples were collected over 6 months from 2 surface water and 2
ground water sites. No 1080 was detected in any of these samples. These
sowing rates were significantly higher than those currently used for pest
control in NZ.
Suren AM, Lambert P. 2006. Do toxic baits containing sodium fluoroacetate (1080)
affect fish and invertebrate communities when they fall into streams?
New Zealand
Journal of Marine and Freshwater Research. 40:531-546
Suren and Lambert conducted an experiment to assess the ecological impact
of 1080 leaching from baits on aquatic invertebrate communities. The
experiment was conducted in four streams in the Mawhera Forest in the Grey
Valley, West Coast. In each stream four sites were selected – 10 m and 100m
downstream and 10 m and 100m upstream from where the 1080 baits were to
be placed. At each site invertebrate communities on 10 replicate rocks were
quantified 4 days and 1 day prior to baits being placed in the stream. Baits
were placed in the stream at a density equivalent to 10x the normal sowing
rate. The invertebrate communities were resampled 1 day and 4 days after the
bait was placed in the stream. No biologically significant effects on the
invertebrate communities as a result of the 1080 were observed.
Conservation House -
Whare Kaupapa Atawhai
PO Box 10 420, Wellington 6143
Telephone (04) 471 0726, Fax (04) 381 3057

Srinivasan MS, Suren A, Wech J, Schmidt J. 2012. Investigating the fate of sodium
monofluoroacetate during rain events using modelling and field studies.
New
Zealand Journal of Marine and Freshwater Research. 46(2):167-178
Srinivasan et al. investigated the fate of 1080 released from baits during a
rainfall event immediately following an aerial 1080 operation. In this field
study, stream and soilwater was sampled in a 148.8 ha headwater catchment
of the Inangahua River, on the West Coast, following the application of 0.15%
1080 Wanganui #7 pellets. The pellets were applied at a rate of 2.5 kg ha-1
within 24 hours of a rainfall event (28 mm in 8 hours, with an additional
100mm falling over the next 9 days). Water sampling occurred between 5
hours and 9 days after the 1080 was applied. The only stream sample that
contained 1080 (at 0.1 µg l-1) was collected 105 minutes after the rain started.
None of the other 15 samples contained 1080 residues. Soilwater samples
were taken approximately 200 mm downhill from baits after 34.4, 57.0 and
60.6 mm of rain had fallen. 1080 residues in these soilwater samples ranged
from 0.5 – 61 µg l-1.
M. S. Srinivasan & A. Suren (2018): Tracking 1080 (sodium fluoroacetate)
in surface and subsurface flows during a rainfall event: a hillslope-scale field study,
Australasian Journal of Water Resources, DOI: 10.1080/13241583.2018.1452329
To link to this article
: https://doi.org/10.1080/13241583.2018.1452329
This field study was conducted on the West Coast of the South Island, New
Zealand, to investigate the transport of 1080 (sodium fluoroacetate) from RS5
baits in rainfall. Two kilograms of baits was hand-laid on a hill adjacent to a
stream, immediately before forecast rain. Overland, groundwater (<1 m from
surface) and stream samples collected during and immediately after the event
recorded no detectable levels (method detection limit, 0.1 ppb) of 1080. Less
than 0.7% of rainfall was recorded as overland flow. Even as a large
proportion of rainfall infiltrated into the soil, likely carrying dissolved 1080
with it, no groundwater contamination was detected. Of the seven soil water
samples that had detectable levels, the highest concentration (1.4 ppb)
observed was below the NZ Ministry of Health standard for drinking water
(3.5 ppb). The findings suggest that the potential for 1080 to contaminate
receiving waters (including soil, ground and surface water) under normal
operational conditions is considered insignificant.
Please note that this letter (with your personal details removed) and enclosed
documents may be published on the Department’s website.
Yours sincerely
Amber Bill
Director, Threats