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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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