Persistence

Page No. Source Quotes from Decision Documents
295 1 Agency App. B “chronic toxicity [studies are] not considered by the Agency to be essential because of the negative mutagenicity data and the unlikelihood of chronic exposure to the substance”
326 1 Agency App. B “In carbon-labelling studies, after 4 days..0.2% of the carbon remained to be excreted..very little 1080 remained in the animal..this [remaining] labelled carbon had [likely] been incorporated into metabolic products in the body”
326 3 Agency App. B “By 96 hours, only trace amounts of the parent compound (fluoroacetate) could be detected in any tissue in the sheep [given 0.1 mg/kg bw of 1080]”
328 4 Agency App. B “As would be expected a proportion of the fluoride release [from 1080 metabolism] is retained in bone”
350 8 Agency App. C “Persistence of 1080 baits on soil is dependent on rainfall, bait type and size. Baits can remain intact for several weeks”
351 2 Agency App. C “1080 residues are persistent in animal carcasses for prolonged periods in winter conditions”
355 2 Agency App. C “17 Days After Treatment (DAT) 1080 stream water without plants [at 23°C] declined to 12 μg/l [from 129 μg/l]..at 7°C slower declines were seen [27 μg / l at 17 DAT]”
355 4 Agency App. C “The fluoride ion concentration was measured in the [aquatic] test systems..mean final concentration of 83 μg/L (assumed to be 17 DAT; not stated in the study). Fluoride ion concentration in the control was 1-2 μg/l”
356 3 Agency App. C “1080 reached a maximum in [aquatic] plants after approx. 24 hours..after 191 hours…traces remained at 11°C [after 0.12 mg/L added to aquaria]”
368 3 Agency App. C “no adverse effects  [were observed at 5 mg/L 1080] on soil microflora [2 species]..isolated from NZ soils previously exposed to 1080”
369 2 Agency App. C “There is limited information available on the degradation of 1080 in animal carcasses..It is clear that 1080 residues remain in the guts of dead animals for prolonged periods (at least 75 days under cool winter conditions..) and only degrade slowly”
369 4 Agency App. C “The reasons for the slow rate of degradation [of 1080 in carcasses] are not clear, but the Agency considers it may be a function of low pH in the gut, absence of bacteria able to degrade 1080, toxicity to gut bacteria, low levels of..invertebrate activity, accompanied by cool temperatures at the time of 1080 bait distribution”
370 1 Agency App. C “Day 75 (after estimated time of death, 1080 concentration of possum stomachs] 4.9 mg/kg
370 2 Agency App. C “day 73 [possum] stomach contents 6 mg/kg”
370 3 Agency App. C “At nearly 6 months..the remaining carcass still had dyed green bait in its stomach but <LOD (LOD not stated)”
370 4 Agency App. C “following a flood [2 months after 1080 drop] 3 carcasses were washed down-river well beyond the boundaries of the operational area [6 km..7 mg/kg; 15 km..6mg/kg; 50 km..<LOD] 1080 measured in the stomach contents..another possum and a stag carcass were found [after 3 months] following another larger flood..40 km..stag 0.5 mg/kg, 50 km..possum 1.7mg/kg”
371 1 Agency App. C “concentrations [of 1080 in rabbit carcasses]..were highly variable..the apparent increase in concentration from that at the time of death..may be due to..dehydration”
372 1 Agency App. C “[1080 concentrations in rabbit carcasses 3 weeks after death..0.02mg/kg (muscle)”
373 1 Agency App. C “many vertebrate pest control operations are conducted in NZ during winter or early spring when ground temperatures are well below 20°C, microbial activity is slower and soils wet. Under dry conditions, microbial activity is also less than optimum, resulting in slower degradation..even when soil temperatures are higher’
373 2 Agency App. C “No studies have been conducted using standard international guidelines to assess the route and rate of degradation of 1080 in soil..while [lab] studies have indicated the ability of some soil organisms to biodegrade 1080, the rate of such degradation under New Zealand conditions is uncertain. Likewise, no robust studies on the adsorption/leaching of 1080 were available to the Agency”
374 1 Agency App. C “No standard guideline studies on the adsorption, desorption or leaching of 1080 were submitted..or located by the Agency”
374 2 Agency App. C “the adsorption and leaching potential of 3 NZ soils [were studied by Parfitt et al]..the Agency only had access to the study as published..and a large number of deficiencies are noted”
376 3 Agency App. C “The [1080-treated] oats remained toxic to rabbits for the duration of the trial (7 weeks) [Australian study]..the relevance of the loss of 1080 from oats under Australian conditions to those in NZ is unknown”
377 1 Agency App. C “the rate of 1080 breakdown in baits in the field was assessed..analysis was complicated by: inconsistent recording of bait size; 1080 loading varying 0.08- 0.15%..rainfall and habitat not recorded in a way which allowed meaningful interpretation..bait type not always being recorded..small sample size (n=8 records for carrot bait)”
377 3 Agency App. C “The 1080 content of the large carrot baits gradually declined during exposure to 200mm rain..whereas no significant loss was observed from the smaller carrot baits.”
380 1 Agency App. C “All [carrot] baits except 1-inch cubes at high rate had </= 10% original 1080 by end week 7”
380 2 Agency App. C “Overall greater 1080 retention by the large [carrot] bait at both concentrations”
380 3 Agency App. C “covered [carrot] baits showed little sign of degradation..”
381 3 Agency App. C “Loss of <40% 1080 after 500 mm rain, indicating binding of 1080 to carrot”
383 4 Agency App. C “[a single bait was placed on soil in each plant container, 9 mg/1080/bait] mean maximum concentration [in broadleaf plants] 0.06 mg/kg 10 DAT, declining to LOD by 38 DAT”
384 2 Agency App. C “[cereal] baits were analysed for 1080 at day 56 and found to contain <1% of the original amount [120 mm rainfall over 56 days]”
387 3 Agency App. C “at day 14 [soil concentrations] had declined to..39 mg/kg [in the highest treatment of 92 mg/kg soil]”
423 3 Agency App. C “5.51 mg/kg ants [one day after exposure to 0.03% 1080 in sucrose] with rapid decline in week following exposure but still measurable after 7 days (0.27 mg/kg ants)”
424 2 Agency App. C “0.033 mg/kg at 240 hours [residues in tree weta after dosing with 15 mg/kg 1080]”
425 2 Agency App. C “Most exposed [native] cockroaches died during the 14 day period [after being fed 0.08% 1080 cereal bait]”
434 2 Agency App. C: Fisk “The purpose of this review..is to assess whether available published evidence is sufficient to assess the persistence of monofluoroacetate”
434 4 Agency App. C: Fisk “[1080] is highly water soluble, involatile, and stable to hydrolysis”
435 1 Agency App. C: Fisk “The pathway and rate [of uptake by organisms] would need to be considered in order to determine whether such a process is important in determining the assessment of overall persistence”
437 2 Agency App. C: Fisk “after 17 days [fluoroacetate and fluorocitrate] levels were almost undetectable [in aquaria with plants, dosed with up to 5 mg/L 1080]”
444 4 Agency App. C: Fisk “[1080] in [water] plant tissue peaked..on day 1..declined to barely detectable levels..on day 13 (7°C) [after dosing with 0.12 mg/L 1080]”
445 2 Agency App. C: Fisk “at 11°C the concentration of 1080 [in aquaria with a species of aquatic plant] declined..at 192 hours there was still 23% of the [1080 dosed at 0.12 mg/L] remaining”
445 3 Agency App. C: Fisk “in the [water] plants, the concentration of [1080] peaked at 24 hr..at 11°C there were still detectable levels at 240 hr [after dosing with 0.12 mg/L 1080]”
447 5 Agency App. C: Fisk “One of the positive [water samples for 1080] was collected before aerial dosing began”
447 6 Agency App. C: Fisk “The one criticism is that soils and water used in the degradation studies could have been subject to prior exposure to fluoroacetate”
449 1 Agency App. C: Fisk “Soils with a prior history of [1080] exposure showed a higher incidence of fluoride degrading micro-organisms”
450 3 Agency App. C: Fisk “there might be problems with persistence in very hot dry areas”
454 3 Agency App. C: Fisk “[Fisk conclusion] if so [possible adaptation of plants and micro-organisms to 1080 has occurred due to its presence from human and plant sources] adaptation must be quite widespread”
475 2 Agency App. E “15% of [carrot] bait more than 5 mm in size caught in [the] canopy and dropped to the ground 10 days after the drop”
521 5 Agency App. F “cases included..150 sheep dying 10 weeks after toxic carrot had been laid in paddocks..78 sheep dying after grazing an airstrip used to load toxic carrot bait..20 weeks after the operation”
560 2 Agency App. H “only 3 [sheep] were used [in a study by Eason, et al., 1994 on 1080 in animal tissues], and there appeared to be considerable variability in the half-life in different animals”
629 1 Agency App. L: Current controls “[Condition of permission issued by DoC for 1080 operations, in current controls] Caution period monitoring: Monitoring physical breakdown of bait and carcasses is required [for 1.5 g/kg 1080 carrots for control of possums and wallabies]” (information should therefore exist on this)
700 2 Agency App. M “The Agency understands that carcasses can reach waterways particularly after significant rain events and agrees there are some aspects which make this a higher risk in relation to drinking water contamination. In particular: a single carcass could [contain] a number of baits [and] the drinking water source may have already been declared free of contamination”
709 1 Agency App. M “One honey sample was found with 15 ppb and this..declined to 3 ppb..after 59 days”
723 11 Agency App. N “While invertebrates feeding on poisoned animal carcasses may be exposed to 1080 residues, the Agency has not assessed exposure from this source. Any effects are likely to be minimal”
726 1 Agency App. N “[1080 residues in aquatic plants] 0.005 mg/kg 1080 after 100 hours”
727 4 Agency App. N “[1080 residues in possum stomach contents] 30.6 mg/kg at Day 25, 4.9 mg/kg at Day 75”
17 2 Applicants’ references “A range of NZ soils, many contaminated by..1080..were examined” (Bong et al., 1979)
19 1 Applicants’ references “Carrot baits were highly water-resistant and showed no decline in 1080..after 200 mm of rain. It is..inadvisable to use carrot bait in arid areas” (Bowen et al., 1995)
20 1 Applicants’ references “1080 concentration in the disposal pit [containing 12, 000 kg toxic bait] decreased to less than 10% of its original level in 12 months” (Bowman, 1999)
45 2 Applicants’ references “baits from one area contained a significant amount of 1080 for 6 weeks [bait type not specified]” (Eason et al., 1991)
74 1 Applicants’ references “[rabbits were administered doses of 1080 to study] the persistence of 1080 in plasma, liver, kidney and muscle” (results only given for plasma) (Gooneratne et al., 1994)
110 1 Applicants’ references “The highest concentration of 1080 detected in the honey [in hives near a poisoned jam bait operation] was 15 ppb and..showed a gradual decay to 3 ppb after 59 days” (Lowe, 1994)
123 2 Applicants’ references “1080 adsorbs to cellulosic leaf litter, and persists in the litter for at least 3 months” (Meads, 1994)
130 1 Applicants’ references “Level of [monofluoroacetate] decreased with time [in samples taken from stomach contents] so that, after 14 days at room temperature, only 50% of the spiked dose could be identified” (Minnaar et al., 2000)
136 2 Applicants’ references “This is in marked contrast to the prolonged persistence of the anticoagulant brodifacoum” (Morgan & Eason, 2002)
146 1 Applicants’ references “[wild possums] from areas previously exposed to a 1080 control-operation avoided 1080 baits” (O’Connor et al., 1999)
149 3 Applicants’ references “earthworm tissue residues at the conclusion of the experiment [28 days of exposure to soil initially dosed with 1080] were either close to, or below, the analytical..limit of detection (0.01 mg/kg)” (O’ Halloran et al., 2003)
152 2 Applicants’ references “In low rainfall areas, it may be appropriate to extend the withholding time until laboratory testing of weathered bait indicates it is safe to restock” (Orr & Bentley, 1994)
154 1 Applicants’ references “The amount of 1080 used per ha is..less than 15g..and if any..is not degraded because of low biological activity (e.g. at low temperature) it will be diluted by soil water and streamwater to very low concentrations” (Parfitt et al., 1994)
154 2 Applicants’ references “we report on the adsorption of 1080 by soil samples with large amounts of hydrous oxides” (Parfitt et al., 1995)
167 1 Applicants’ references “three rabbit populations [in Australia] repeatedly exposed to 1080 are becoming resistant to it. By comparing results from a similar study in 1979,they found that more than double the amount of poison is now needed to kill the same number of animals” (Randerson, 2002)
189 1 Applicants’ references “The rainfall pattern is an important factor in the weathering of poisoned rabbit baits but it is not possible to lay down specific rules about the time domestic stock should be kept off recently poisoned areas” (Staples, 1968)
107 1 Submitter 9074 “Dogs have been killed by chewing up the dried carcass of a rat or mouse killed with 1080 several months before”
14 4 Committee Decision “In wet environments 1080 residues disappear in one to four weeks”
14 5 Committee Decision “in dry or cold conditions it can take months to break down”
58 2 Committee Decision “the baits cover only a small proportion of the total treatment area and..while 1080 will leach from baits during rain, any effect will be highly localised and will not persist over time”
65 1 Committee Decision “1080 residues in the carcasses of poisoned possums may be very slow break down”