OECD 218/219
Chachchaya Cervinkova 3 'Lucie Langova
Sediment-water Chironomid toxicity test - using spiked sediment/ spiked water (oecd 218/219)
http://www.oecd-ilibrary.org/content/book/9789264070288-en
• investigate the effects of chemical exposure to the sediment-dwelling larvae of freshwater species (Chironomus sp.; C.riparius -preferovaný, C. tentans - možné také použít, ale delší doba líhnutí, C. yoshimatsui)
• Exposure scenario; sediment/ water spiking
(process of adding test substance into test sediment/ water)
Sediment
• Artificial sediment (uncontaminated, clean,
standard matrix, no seasonal variability, no other organisms, no pre-treat)
- 4 - 5 % vysušená rašelina (velikost částic < 1 mm)
- 20 % kaolinový jíl s obsahem kaolinitu min. 30 % JL 75 - 76 % křemenný písek (min. 50 % zrn 0,05 - 0,2
mm)
- CaCO3 se přidá, aby výsledné pH bylo 7,0 ± 0,5
^ \
Přírodní
- Stanovení pH, obsah organického uhlíku, poměr C/N
- Bez kontaminace a jiných organismů
(konkurence, konzumace larev)
- Nutnost stabilizace (alespoň 7 dní)
Voda
Studniční Povrchová
Provozní ^\
Uměle připravená ^^jÉjfelk
Zjištění tvrdosti a obsahu amoniaku v kontrolních a jedné testovací nádobě s nejvyšší
koncentrací na začátku a na konci testu
First instar chironomid larvae are exposed to a concentration range of chemical in
sediment-water system
Testovaná látka je spikovaná do sedimentu/vody a larvy jsou následně zavedeny do zkušebních kádinek
Endpoint ; total number of adults emerged and time of emergence, larvae survival and growth (10 days)
• C. riparius, C. yoshimatsui - 12 and 23
days
• C. tentans - 20 - 65 days
• At least 5 concentrations and 4 replicates (ECXI larvae survival and growth estimation test)
Aeration; 7 days
Water
overlying 6 cm
s; : Sea. si;5 ;Cm ( < 3 : cm£!
2nd - 3rd day - take egg masses place in new culture medium
First instar begin to hatch couple days later
Add 20 of first instar larvae
(stop aeration) Then, continues aeration
Water
overlying 6 cm
s; : Sed. si;5 ;Cm; ( < i : cm^
24 hours later, spike the test substance into the overlying water
Then, continues aeration
Food; daily or 3 times/week Finely ground fish food Temp - 20
Light - 16 hours (500 - 1000 lux)
• Exposure duration
-- C. riparius, C. yoshimatsui - 20 - 28 days - C. tentans - 28 - 65 days
> Observation
number of female and male, development time, abnormal behaviour
number of pupae
compare with control (> 70%)
Plumose antennae
Source: www.williamfisherphotography.com
Blind mosquitoe
Important food source of fish and predatory
Source:
http://www.ces.ncsu.edu http://www.mzephotos.com http://www.morgellonsuk.org.uk http://flyfishingreporter.com http://www.nature.com/
Adult r^Ti^k
A: the nvlaa screen
B: Üie inverted plastic cup^.
C: the liples^ exposure beafeer
D: the water exchange screen porte I: water F: sediment
Poměr líhnutí
ER = n
n
a
ne: pakomáři vylíhnutí v nádobě na: larvy vložené do nádoby
Validace: ER kontrola > 0,7
Average development rate = time span of introduction of larvae and
emergence of the experimental of midges
i =1 Jk
X = Avg. development rate per vessel
i = index of inspection interval
m = maximum number of inspection intervals § = number of midges emerged in the inspection interval i lip = total number of midges emerged at the end of experiment (= i■ £ )
■■.■■■.".■■■X- IV/
X, = develoment rate of the midges emerged in interval i
Vyhodnocení
Statistická analýza
- Chí-kvadrát test -ANOVA
- t-test
- Regresní analýza L atd.
• Děkujeme za pozornost!