A Protocol for Responding to Adverse Fish Health Events and ...
A Protocol for Responding to Adverse Fish Health Events and ...
A Protocol for Responding to Adverse Fish Health Events and ...
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A <strong>Pro<strong>to</strong>col</strong> <strong>for</strong> <strong>Responding</strong> <strong>to</strong> <strong>Adverse</strong> <strong>Fish</strong> <strong>Health</strong> <strong>Events</strong> <strong>and</strong> Chemical<br />
Overspray/Drift Incidents at Sunl<strong>and</strong> <strong>Fish</strong> Hatchery by Munro Mortimer<br />
Context<br />
If <strong>and</strong> when future adverse fish health events occur at the Sunl<strong>and</strong> <strong>Fish</strong> hatchery, it<br />
may be appropriate <strong>to</strong> collect environmentally relevant materials (water, soil,<br />
sediment, pond vegetation, whole fish <strong>and</strong> fish tissues, surface wipes, <strong>and</strong> deployed<br />
droplet capture devices) <strong>for</strong> labora<strong>to</strong>ry analysis.<br />
Capacity <strong>to</strong> respond in an effective <strong>and</strong> timely manner involves having staff trained<br />
in the techniques required, <strong>and</strong> having the necessary equipment on h<strong>and</strong> at an<br />
appropriate location/s.<br />
Collecting environmental samples <strong>for</strong> chemical testing<br />
It is essential that all samples are collected in such that:<br />
1. Material sent <strong>for</strong> analysis is representative of the environmental location<br />
sampled;<br />
Ensuring materials are representative usually means collecting composite<br />
samples. For example in sampling a pond, water samples should be taken<br />
from several points <strong>and</strong> mixed in equal proportions <strong>to</strong> get a composite <strong>for</strong><br />
analysis.<br />
Unless water is well‐mixed <strong>and</strong> shallow, contaminant concentrations may<br />
vary with depth. This needs <strong>to</strong> be accounted <strong>for</strong> in the sampling design ‐. E.g.<br />
composites through depth or discrete composites at st<strong>and</strong>ard depths.<br />
The same principles apply <strong>to</strong> sampling plants, fish, soils, sediments.<br />
2. If comparisons are <strong>to</strong> be made between locations or against a benchmark,<br />
then statistical requirements should be met (e.g. multiple composite<br />
samples). The relevance <strong>and</strong> availability of comparable material from<br />
reference locations should also be considered;<br />
3. The interpretational requirements of the data should be built in<strong>to</strong> the<br />
sampling design;<br />
For example if water is being sampled, is it a filtered sample or an unfiltered<br />
sample (or both) that is required? If filtration is appropriate, then field<br />
filtration may be necessary;<br />
4. Not contaminated as a result of incorrect h<strong>and</strong>ling or s<strong>to</strong>rage;<br />
A schedule of the appropriate containers <strong>and</strong> preservatives is attached. This<br />
is taken from the Qld EPA (now DERM) Water Quality Sampling Manual as<br />
updated <strong>for</strong> the new EPP(Water) Sampling Manual 2009.<br />
1
In general, amber solvent‐washed glass bottles with Teflon lid liners are<br />
required <strong>for</strong> organics, <strong>and</strong> acid‐washed glass or plastic (not <strong>for</strong> mercury<br />
analysis) bottles are required <strong>for</strong> metals <strong>and</strong> metalloids.<br />
Gloves should be worn <strong>and</strong> changed frequently. Ideally, samples are collected<br />
directly in<strong>to</strong> the s<strong>to</strong>rage container. If this is impractical, an interim container<br />
may be used but care is needed <strong>to</strong> avoid cross‐contamination (e.g. clean<br />
between samples/sites).<br />
<strong>Fish</strong> tissues (or whole animals), plants/plant tissues, soils, <strong>and</strong> sediments,<br />
should be s<strong>to</strong>red in solvent‐washed glass or foil wrapped (organics), or s<strong>to</strong>red<br />
in acid‐washed glass or plastic <strong>for</strong> metals analysis.<br />
5. Loss of contaminant between sampling <strong>and</strong> analysis is minimised (covered<br />
under 4 above);<br />
<strong>Fish</strong> <strong>and</strong> fish tissues <strong>for</strong> veterinary examination<br />
For pathology, the procedures published in “Cultured Aquatic Animals – preparation<br />
<strong>for</strong> Veterinary Labora<strong>to</strong>ry Examination (Second Edition)” QDPI should be followed.<br />
Sprayed surfaces<br />
Sampling of sprayed surfaces (e.g. buildings, pathways, vegetation) can be done by<br />
taking wipe samples. The pro<strong>to</strong>col from the Qld EPA (now DERM) Water Quality<br />
Sampling Manual as updated <strong>for</strong> the new EPP(Water) Sampling Manual 2009 is<br />
attached.<br />
Overspray <strong>and</strong> Spray Drift sampling<br />
Advice on appropriate absorbent pads has been sought from UQ, Gat<strong>to</strong>n. They have<br />
indicated willingness <strong>to</strong> provide materials <strong>and</strong> advice – a modest quote <strong>to</strong> cover cost<br />
of materials is expected.<br />
Quality Control<br />
Field blanks <strong>and</strong> blind replicates should be included.<br />
Samples should be labelled as they are collected <strong>and</strong> a written record made (what,<br />
where, when, by whom, etc.). Coded labels are fine (e.g. initials <strong>and</strong> site numbers<br />
marked on a map).<br />
2
Table 2 ‐ Water Samples ‐ Containers <strong>and</strong> Preservation Methods<br />
Container codes: V, Volume: Typical sample volume, mL. [see note 1 ]. W, Washing: A = Acid, D = Detergent, S = Solvent, W = Water. M, Material: G = Borosilicate Glass, P = Plastic (examples: Polyethylene, PTFE, PET, polypropylene or<br />
similar) [‡] Except where specifically stated otherwise, put sample in container first, THEN add the preservative/s – if more than one, in the order shown thus: [A] [B].<br />
[§] ‘Refrigerate’ = cool <strong>to</strong> 1‐4C; ‘Freeze’ = freeze <strong>to</strong> ‐20C. [†] Denotes recommended maximum time from collection in the field <strong>to</strong> analysis in the labora<strong>to</strong>ry.<br />
Container Code<br />
Preservation Procedure<br />
(as above)<br />
Filling Method<br />
Rec. Max.<br />
Quality Characteristic<br />
How much: (a) OR (b)<br />
<strong>and</strong>/or<br />
Preservative<br />
S<strong>to</strong>rage Conditions holding<br />
(WATER SAMPLES) V W M Sample Filtering (if any)<br />
<strong>to</strong> add [‡]<br />
(a) Mass or (b) <strong>to</strong> pH<br />
[§]<br />
period [†]<br />
Volume shown<br />
Other Instructions<br />
ACIDITY AND ALKALINITY 250 D P Fill container completely <strong>to</strong><br />
exclude air<br />
None — — Refrigerate 24 hours Analyse in the field if practicable [consult<br />
analyst about procedure]<br />
ADSORBABLE ORGANIC HALIDE<br />
(A.O.X.)<br />
1000 A G Fill container completely <strong>to</strong><br />
exclude air<br />
Nitric Acid — 1‐2 Refrigerate in the dark 3 days Transport sample promptly <strong>to</strong> labora<strong>to</strong>ry<br />
so that analysis can be started as soon as<br />
practicable<br />
BACTERIA 200 See G or<br />
Refrigerate Maximum<br />
Escherichia coli <strong>and</strong><br />
note P<br />
24 hours<br />
THERMOTOLERANT<br />
BACTERIA<br />
Enterococci<br />
[2]<br />
See note [ 3 ]<br />
BIOCHEMICAL OXYGEN<br />
DEMAND (B.O.D.)<br />
1000 W G or<br />
P<br />
Fill container completely <strong>to</strong><br />
exclude air.<br />
None — — Refrigerate in the dark 24 hours Check with the labora<strong>to</strong>ry on suitable<br />
arrival time<br />
BORON 100 D P Fill container completely <strong>to</strong> None — — — 1 month —<br />
exclude air<br />
BROMIDE 100 D P — None — — Refrigerate in the dark 1 month —<br />
CHEMICAL OXYGEN DEMAND 100 A G or Fill container completely <strong>to</strong> Sulphuric Acid — 1‐2 Refrigerate<br />
7 days —<br />
(C.O.D.)<br />
P exclude air<br />
Freeze<br />
1 month<br />
CHLORIDE 100 D P — None — — — 1 month —<br />
CHLORINE, Free 100 D P — None — — Keep sample out of 5 min Determine immediately on site<br />
direct sunlight<br />
CHLORINE, Total 100 D P — None — — Keep sample out of<br />
direct sunlight<br />
5 min Determine immediately on site<br />
CHLOROPHYLL<br />
use 1 of the 2 methods<br />
see note [4]<br />
See<br />
note<br />
[4]<br />
1000 D G or<br />
P<br />
See note [4] – keep filter paper<br />
[filtered liquid is not required<br />
<strong>for</strong> this test]<br />
None — — Refrigerate in the dark 24 hours Sample must be transported in the dark<br />
Wrap folded filter paper<br />
in aluminium foil <strong>and</strong><br />
freeze in the dark<br />
1 month —<br />
COLOUR 500 D P — None — — Refrigerate in the dark 48 hours —<br />
3
CONDUCTIVITY<br />
use 1 of the 2 methods<br />
CYANIDE, Total<br />
see note [ 5 ]<br />
100 W P Fill container completely <strong>to</strong> None — — — 24 hours Determine in situ or on site if possible<br />
exclude air<br />
Refrigerate 1 month<br />
500 W P — Sodium Hydroxide Solution* — 12 Refrigerate in the dark 24 hours *Caution: this procedure can create<br />
lethal HCN gas<br />
DISSOLVED OXYGEN (D.O.) 300 W G — None — — — — Determine in situ or on site<br />
Winkler solution S<strong>to</strong>re in the dark 24 hours<br />
FLUORIDE 200 D P — None — — — 1 month PTFE (poly‐tetrafluoroethylene)<br />
containers are unsuitable<br />
HERBICIDES AND PESTICIDES:<br />
Herbicides<br />
HERBICIDES AND PESTICIDES:<br />
Carbamates<br />
Pyrethrins<br />
Synthetic pyrethroids<br />
Organo‐chlorine,<br />
Organo‐phosphorus <strong>and</strong><br />
Nitrogen‐containing<br />
Pesticides<br />
1000 S G* Do not pre‐rinse container with<br />
sample material. Do not<br />
completely fill sample container<br />
(leave head space of approx.<br />
1‐2 cm depth)<br />
1000 S G* Do not pre‐rinse container with<br />
sample material. Do not<br />
completely fill sample container<br />
(leave head space of approx.<br />
1‐2 cm depth)<br />
Sodium Thiosulphate –<br />
see note [6]<br />
Sodium Thiosulphate –<br />
see note [6]<br />
80 mg per L<br />
sample<br />
80 mg per L<br />
sample<br />
— Refrigerate in the dark 7 days * Lid of sample container must have<br />
insert of Aluminium or PTFE<br />
(poly‐tetrafluoroethylene). Protect<br />
sample from light<br />
— Refrigerate 7 days * Lid of sample container must have<br />
insert of Aluminium or PTFE<br />
(poly‐tetrafluoroethylene)<br />
HYDROCARBONS, Petroleum 1000 S G Do not pre‐rinse container with Sulphuric Acid — 1‐2 Refrigerate 1 month —<br />
sample material. Fill bottle<br />
completely with sample (no<br />
head space)<br />
IODIDE 500 D P — None — — Refrigerate in the dark 1 month —<br />
LIGNINS AND TANNINS 250 W G — None — — Refrigerate 7 days —<br />
METALS – Calcium or<br />
Magnesium<br />
see note [ 7 ] re preserving;<br />
METALS Chromium,<br />
Hexavalent<br />
see note [ 8 ]<br />
250 A P Fill container completely <strong>to</strong><br />
exclude air<br />
Nitric Acid — 1‐2 — 1 month —<br />
None — — — 7 days<br />
100 A P — None — — Refrigerate 24 hours —<br />
4
METALS – Mercury 250 A G For ‘Dissolved’ <strong>for</strong>m, filter on<br />
site; see note [9]<br />
METALS– Potassium or Sodium<br />
use 1 of the 2 methods<br />
[A] Nitric Acid — 1‐2 — 1 month If sample is wastes or contaminated<br />
waters, more Potassium Dichromate may<br />
be needed:—<br />
[B] Potassium Dichromate<br />
50 mg/mL<br />
Per 250 mL<br />
sample—<br />
5 mL or more<br />
see last<br />
column<br />
— • If sample is initially clear or a pale<br />
colour, adding 5 mL of preservative<br />
should turn it a distinct yellow. If the<br />
colour appears but then fades, more<br />
preservative is needed; so add a<br />
further 5 mL. Repeat if necessary.<br />
• If sample is initially a dark colour, it may<br />
be difficult <strong>to</strong> determine whether<br />
enough preservative has been added.<br />
Discuss with the analyst be<strong>for</strong>e<br />
sampling if practicable.<br />
Both preservation steps are required<br />
100 W P — None — — — 1 month —<br />
250 A P<br />
Nitric Acid 1‐2 1 month Permits measurement with other metals<br />
METALS– others: Aluminium,<br />
Arsenic, Barium, Cadmium,<br />
Chromium – Total<br />
(hexavalent + trivalent),<br />
Cobalt, Copper, Iron, Lead,<br />
Manganese, Molybdenum,<br />
Nickel, Selenium, Silver,<br />
Uranium<br />
see note [8]<br />
NUTRIENTS: AMMONIA<br />
use 1 of the 2 methods<br />
NUTRIENTS: NITRATE<br />
use 1 of the 2 methods<br />
NUTRIENTS: NITRITE<br />
use 1 of the 2 methods<br />
250 A P For ‘Dissolved’ <strong>for</strong>m, filter on<br />
site; see note [9]<br />
Nitric Acid — 1‐2 — 1 month —<br />
100 W P Filter on site;<br />
see note [9]<br />
None — — Refrigerate 24 hours S<strong>to</strong>re in area free of contamination<br />
(ammonia vapour may permeate the<br />
Filter on site;<br />
see note [9]<br />
None — — Freeze 1 month walls of containers, even if made of high<br />
density polyethylene)<br />
100 W P [Unfiltered sample] None — — Refrigerate 24 hours —<br />
Filter on site;<br />
see note [9]<br />
None — — Freeze 1 month<br />
100 W P — None — — — 24 hours Have sample analysed as soon as possible<br />
after collection<br />
Freeze 48 hours<br />
5
NUTRIENTS: NITROGEN, TOTAL<br />
KJELDAHL (T.K.N.) or TOTAL<br />
(T.N.)use 1 of the 2 methods<br />
NUTRIENTS: PHOSPHORUS,<br />
Dissolved use 1 of the 2<br />
methods<br />
NUTRIENTS: PHOSPHORUS,<br />
Total use 1 of the 2 methods<br />
250 W P — None — — Refrigerate 24 hours —<br />
100 W P Filter on site;<br />
see note [9]<br />
Freeze 1 month<br />
None — — Refrigerate 24 hours —<br />
Freeze 1 month<br />
250 W P — None — — Refrigerate 24 hours —<br />
OIL AND GREASE 1000 S G Do not pre‐rinse container with<br />
sample material. Fill bottle<br />
completely with sample (no<br />
head space)<br />
Freeze 1 month<br />
Sulphuric Acid — 1‐2 Refrigerate 1 month —<br />
ORGANOTINS (e.g. TBT) 1000 S G — None — — Refrigerate 7 days * Lid of sample container must have<br />
insert of Aluminium or PTFE<br />
(poly‐tetrafluoroethylene). Protect<br />
sample from light<br />
pH 100 D P — None — — Refrigerate 6 hours Determine in situ or on site if practicable<br />
POLYCHLORINATED BIPHENYLS<br />
(P.C.B.)<br />
POLYNUCLEAR AROMATIC<br />
HYDROCARBONS (P.A.H.)<br />
1000 S G* Do not pre‐rinse container with<br />
sample material. Do not<br />
completely fill sample container<br />
(leave head space of approx.<br />
1‐2 cm depth)<br />
1000 S G Do not pre‐rinse container with<br />
sample material. Do not<br />
completely fill sample container<br />
(leave head space of approx.<br />
1‐2 cm depth)<br />
Sodium Thiosulphate –<br />
see note [6]<br />
Sodium Thiosulphate –<br />
see note [6]<br />
80 mg per L<br />
sample<br />
80 mg per L<br />
sample<br />
— Refrigerate in the dark 7 days * Lid of sample container must have<br />
insert of Aluminium or PTFE<br />
(poly‐tetrafluoroethylene)<br />
— Refrigerate in the dark 7 days —<br />
SOLIDS, Dissolved 1000 D P Fill container completely <strong>to</strong> None — — Refrigerate 24 hours —<br />
exclude air<br />
SOLIDS, Suspended 1000 D P — None — — Refrigerate 24 hours —<br />
SULPHATE 200 W P — None — — Refrigerate 7 days —<br />
SURFACTANTS, ANIONIC 500 [ 10 ] G — Sulphuric acid — 1‐2 Refrigerate 48 hours Glassware must not have been washed<br />
with detergent previously<br />
SURFACTANTS, NON‐IONIC 500 [10] G — Formaldehyde 25 mL per L<br />
sample<br />
— Refrigerate 1 month Glassware must not have been washed<br />
with detergent previously<br />
TRIHALOMETHANES <strong>and</strong><br />
HALOACETIC ACIDS<br />
200 S G* Fill container completely <strong>to</strong><br />
exclude air<br />
Ascorbic Acid, or<br />
0.125 g per<br />
200 mL<br />
sample<br />
— — 14 days *Glass vial with cap having PTFE‐faced<br />
septum<br />
6
Sodium Thiosulphate –<br />
see note [6]<br />
Ammonium chloride 0.2g per 200<br />
mL sample<br />
TURBIDITY 100 D P — None — — — 24 hours If practicable, determine in situ or on site<br />
16 mg per<br />
200 mL<br />
sample<br />
7
Table 3 ‐ Sediment Samples ‐ Containers <strong>and</strong> Preservation Methods<br />
Container codes: V, Volume: Typical sample volume, mL. [see note 1]. W, Washing: A = Acid, D = Detergent, S = Solvent, W = Water. M, Material: G = Borosilicate Glass, P = Plastic (examples: PTFE, polyethylene, PET, polypropylene or<br />
similar) [‡] Except where specifically stated otherwise, put sample in container first, THEN add the preservative/s – if more than one, in the order shown thus: [A] [B].<br />
[§] ‘Refrigerate’ = cool <strong>to</strong> between 1‐4C; ‘Freeze’ = freeze <strong>to</strong> ‐20C. [†] Denotes recommended maximum time from collection in the field <strong>to</strong> analysis in the labora<strong>to</strong>ry.<br />
Container Code<br />
Preservation Procedure<br />
Rec. Max.<br />
Quality Characteristic (as above) Filling Method Preservative How much: (a) OR (b) S<strong>to</strong>rage Conditions holding Other Instructions<br />
(SEDIMENT SAMPLES) V W M <strong>to</strong> add [‡] (a) Mass or<br />
Volume<br />
HEAVY METALS<br />
See note [ 11 ]<br />
(b) <strong>to</strong> pH<br />
shown<br />
[§] period [†]<br />
375 A G — None — — — 7 days —<br />
Ziplock Plastic Bag — None — — Freeze 1 month<br />
ORGANOTINS (e.g. TBT) 375 S G None — — Refrigerate 7 days —<br />
PESTICIDES AND HERBICIDES<br />
See note [ 12 ]<br />
SEMI‐VOLATILE ORGANICS<br />
375<br />
375<br />
S<br />
S<br />
G<br />
G<br />
—<br />
—<br />
None<br />
None<br />
—<br />
—<br />
—<br />
—<br />
Refrigerate<br />
Refrigerate<br />
7 days<br />
7 days<br />
—<br />
—<br />
TOTAL ORGANIC CARBON 375 S G — None — — Refrigerate 7 days —<br />
(T.O.C.)<br />
See note [12]<br />
Ziplock Plastic Bag — None — — Freeze 1 month<br />
8
Note [1]<br />
Note [2].<br />
Note [3].<br />
Note [4].<br />
The volume shown is a typical volume <strong>for</strong> a single determination. The actual volume needed depends on many fac<strong>to</strong>rs. If practicable, discuss with the analytical labora<strong>to</strong>ry<br />
be<strong>for</strong>e sampling.<br />
Sterile containers are required as specified in AS/NZS 2031‐2001. For samples from chlorinated sources, these must contain Sodium Thiosulphate be<strong>for</strong>e sampling. The<br />
concentration must be such as will produce a concentration of at least 100 mg/mL in the sample. Where bottles are prepared by the labora<strong>to</strong>ry, they should be supplied<br />
already containing the required amount of Sodium Thiosulphate. Sodium Thiosulphate neutralizes the chlorine, thus preventing further bactericidal effects on organisms in the<br />
water during transit.<br />
AS/NZS 2031‐2001 indicates that microbiological examination should commence within 6 hours of collection; under exceptional circumstances this may be extended <strong>to</strong> a<br />
maximum of 24 hours. The analyst should attach a note <strong>to</strong> the test report stating the time interval between sample collection <strong>and</strong> testing.<br />
Filter the sample <strong>and</strong> submit the filter paper itself (containing the particulates so removed) <strong>to</strong> the analyst. Filter the sample in the field using vacuum filtration equipment.<br />
Filter the sample through a fine glass fibre filter (Whatman GF/C or equivalent). The vacuum applied across the filter should be no more than 40 cm of mercury, <strong>to</strong> avoid<br />
possible rupture of cells <strong>and</strong> consequent release of chlorophyll. The volume of sample needed will depend on the concentration of particulate matter present; a typical<br />
volume <strong>to</strong> filter is 1000 mL, but <strong>for</strong> samples with high loadings, the filter can become clogged be<strong>for</strong>e this volume has passed through. You must record the volume that has<br />
actually passed through the filter, <strong>and</strong> give this in<strong>for</strong>mation <strong>to</strong> the analyst with the sample. Filters must not be <strong>to</strong>uched with fingers <strong>and</strong> all sample h<strong>and</strong>ling apparatus must<br />
be kept free of acids as this causes degradation of chlorophyll. Place filter paper in a container that excludes light (example: a small tube completely wrapped in aluminium foil)<br />
<strong>for</strong> transport <strong>to</strong> analyst.<br />
Note [5]. When requesting analysis, specify which <strong>for</strong>m you require <strong>to</strong> be determined.<br />
Note [6].<br />
Note [7].<br />
Note [8].<br />
Note [9].<br />
Preservative is needed only if sample is chlorinated. Preservative should be in the bottle prior <strong>to</strong> filling with sample.<br />
Second method [no preservation] can be used only where sample is— [a] of pH 8 <strong>and</strong> low carbonate content; <strong>and</strong> [b] drawn solely <strong>for</strong> determination of Calcium,<br />
Magnesium or Hardness.<br />
When collecting a sample <strong>for</strong> determination of Chromium (VI), it is suggested that you also collect a sample <strong>for</strong> determination of Total Chromium <strong>and</strong> submit both <strong>for</strong> analysis.<br />
This allows the labora<strong>to</strong>ry <strong>to</strong> per<strong>for</strong>m the simpler test <strong>for</strong> Total Chromium first; then, if none is detected, it need not carry out the more complex test <strong>for</strong> Hexavalent (VI)<br />
Chromium.<br />
Filter sample in the field, through 0.45 m poly ether sulphone filter, preferably using fully‐enclosed pressure filtering equipment, such as single‐use syringe (50 mL) with<br />
0.45 m single‐use filter. For turbid samples a glass fibre pre‐filter should also be used <strong>to</strong> make filtering easier.<br />
Note [10]. Containers <strong>to</strong> be methanol‐rinsed glass in accordance with AS 5667.1:1998<br />
Note [11].<br />
You must specify which metals are <strong>to</strong> be determined on the sample.<br />
9
Note [12].<br />
If analysis is required <strong>for</strong> <strong>to</strong>tal organic carbon (T.O.C.) as well as <strong>for</strong> PESTICIDES AND HERBICIDES, the same sample will suffice <strong>for</strong> both analyses.<br />
10
Wipe‐sampling of surface contaminants (also known as “swab<br />
sampling”)<br />
The presence of surface contamination (<strong>for</strong> example by dusts, spray drift, or residues<br />
from containment) can be assessed by taking a swab from the surface concerned.<br />
This is a useful technique <strong>for</strong> testing <strong>for</strong> the presence of contaminants on a surface.<br />
However, although there are regula<strong>to</strong>ry measures of surface contamination <strong>for</strong> some<br />
contaminants (<strong>for</strong> example <strong>for</strong> “PCB‐free” materials) the use of wipe samples <strong>for</strong> a<br />
purpose other than detecting contaminant presence (<strong>for</strong> example comparing surface<br />
contamination on a spatial basis, <strong>for</strong> checking the efficacy of decontamination, or <strong>for</strong><br />
comparison with environmental effects guidelines) is not recommended. In the latter<br />
case, the units are incompatible (surface contamination is measured in mass per unit<br />
area, <strong>and</strong> environmental effect levels are concentrations per unit volume or mass).<br />
Wipe‐sampling is applicable <strong>for</strong> assessing surface contamination both from organic<br />
contaminants such as pesticides <strong>and</strong> from inorganics such as metals. Swipe sampling<br />
is most efficient on smooth surfaces such as glass, metal, painted surfaces, <strong>and</strong><br />
smooth vegetation surfaces such as leaves. It is less effective on surfaces that are<br />
rough <strong>and</strong>/or porous such as timber <strong>and</strong> concrete.<br />
There is no st<strong>and</strong>ard method <strong>for</strong> wipe‐sampling, although there are published<br />
st<strong>and</strong>ard methods <strong>for</strong> specific tasks (<strong>for</strong> example ASTM E1728 <strong>for</strong> sampling lead dust<br />
from surfaces).<br />
The design of a wipe‐sampling pro<strong>to</strong>col involves choosing a material <strong>for</strong> the swab, a<br />
solvent <strong>to</strong> wet it, <strong>and</strong> a st<strong>and</strong>ard area <strong>to</strong> swab. A minimum of 100 sq cms surface<br />
should be wiped. If only trace levels of contamination are anticipated, wiping a much<br />
larger surface area is advisable, <strong>for</strong> example up <strong>to</strong> a square metre. For wiping such<br />
large areas, more than one wipe may be used, <strong>and</strong> wipes can be pooled <strong>for</strong> analysis.<br />
A variety of readily available materials are suitable <strong>for</strong> use as swabs. The portions of<br />
material chosen should be uni<strong>for</strong>m in all respects <strong>and</strong> free of measurable<br />
contamination in respect of analytes of interest. The latter should be checked by<br />
analysing blank swabs. Examples of suitable swab material supplied in uni<strong>for</strong>m packs<br />
are filter papers <strong>and</strong> small gauze pads such as those used <strong>for</strong> small wound dressing.<br />
The wetting solvent of choice in most cases is an organic solvent such as isopropyl<br />
alcohol or hexane. Methylated spirits purchased in a glass bottle from a pharmacy<br />
can be used. Water is only appropriate <strong>for</strong> inorganic dusts. The purity of the solvent<br />
needs <strong>to</strong> be assured against the possibility that it is a source of any of the analytes of<br />
interest (<strong>for</strong> example by testing a blank)<br />
The sampling pro<strong>to</strong>col should define a st<strong>and</strong>ard area <strong>for</strong> swabbing, as well as a<br />
st<strong>and</strong>ard method of taking the swab. For example it might involve wetting of each<br />
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swab with 2 ml of alcohol, <strong>and</strong> wiping the swab across a pre‐marked 10 cm x 50 cm<br />
surface from left <strong>to</strong> right until the whole surface has been covered, then wiping<br />
again from <strong>to</strong>p <strong>to</strong> bot<strong>to</strong>m, while applying an even pressure <strong>and</strong> holding the swab flat<br />
against the surface. An alternative <strong>to</strong> pre‐marking a surface is <strong>to</strong> swab within the<br />
boundaries of a pre‐cut template held against the surface (the template would need<br />
<strong>to</strong> be appropriately cleaned between sites). In the case of leaves, a uni<strong>for</strong>m area<br />
could be approximated by swabbing the surfaces of a fixed number of leaves of<br />
similar size at each site.<br />
Nitrile gloves should be worn <strong>and</strong> changed between sites, <strong>and</strong> each used swab<br />
sealed in a labelled sampling container appropriate <strong>for</strong> the s<strong>to</strong>rage of the analytes of<br />
interest, <strong>for</strong> example a solvent‐washed jar if pesticides are of interest.<br />
.<br />
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