natgillin/translations-raw huggingface dataset:
In some studies there may be a marked difference between the derived time zero value, C0,d, and the mean measured time zero concentration.
Cianokobalamin (B12)
C0,m (see last bullet point of paragraph 159 of this test method).
Biotin
If C0,d is very much lower than C0,m (C0,d << C0,m), the difference may suggest the presence of undigested spiked food in the gut.
Kombinirana osnovna raztopina vitaminov se hrani zamrznjena v majhnih enakih količinah.
This may be tested experimentally by conducting separate analysis on the excised gut if additional (whole fish) samples were taken and stored at the end of the uptake phase.
Vitamini se medijem dodajo tik pred uporabo.
Otherwise, if a statistically valid outlier test applied to the depuration phase linear regression indicates that the first sample point of depuration is erroneously elevated, carrying out the linear regression to derive k2 but omitting the first depuration concentration point may be appropriate.
Da se prepreči obarjanje soli pri pripravi celotnega medija, se doda enake količine osnovnih raztopin v približno 500–800 ml deionizirane vode, ki se nato dopolni do enega litra.
In such cases, if the uncertainty in the linear regression is greatly decreased, and it is clear that approximately first order depuration kinetics were obeyed, it may be appropriate to use the resulting C0,d and k2 values in the assimilation efficiency calculation.
Prvi opis medija M4 je objavljen v Elendt, B. P. (1990).
This should be fully justified in the report.
ANALIZA SKUPNEGA ORGANSKEGA OGLJIKA (TOC) IN IZDELAVA NOMOGRAMA ZA VSEBNOST TOC V HRANI IZ ALG
It is also possible that non-first order kinetics were operating in the depuration phase.
Ugotovljeno je bilo, da se vsebnost ogljika v hrani iz alg običajno ne meri neposredno, ampak na podlagi korelacij (tj. nomogramov) z nadomestnimi meritvami, kot sta število celic alg ali absorbanca svetlobe.
If this is likely (i.e. the natural logarithm transformed data appear to follow a curve compared with the straight-line linear regression plot), then the calculations of k2 and C0,d are unlikely to be valid and the advice of a biostatician should be sought.
Skupni organski ogljik (TOC) je bolje meriti z visokotemperaturno oksidacijo kot pa z UV ali persulfatnimi metodami.
If C0,d is very much higher than the measured value (C0,d >> C0,m) this may indicate: that the substance was depurated very fast (i.e. sampling points approached the limit of quantification of the analytical method very early in the depuration phase, cf.
(Za nasvet glej: The Instrumental Determination of Total Organic Carbon, Total Oxygen Demand and Related Determinands 1979, HMSO 1980; 49 High Holborn, London WC1V 6HB).
Section 6 below); that there was a deviation from first order depuration kinetics; that the linear regression to derive k2 and C0,d is flawed; or that a problem with the measured concentrations in the study occurred at some sampling time points.
Za izdelavo nomograma je treba alge ločiti od gojišča s centrifugiranjem, ki mu sledi ponovno suspendiranje v destilirani vodi.
In such cases the linear regression plot should be scrutinised for evidence of samples at or near the limit of quantification, for outliers and for obvious curvature (suggestive of non-first order kinetics), and highlighted in the report.
Nadomestni parameter in koncentracija TOC za vsak vzorec se izmerita trikrat.
Any subsequent re-evaluation of the linear regression to improve estimated values should be described and justified.
Analizirati je treba slepe kontrolne vzorce z destilirano vodo in izpeljati koncentracijo TOC iz koncentracije TOC v vzorcu alg.
If marked deviation from first order kinetics is observed, then the calculations of k2 and C0,d are unlikely to be valid and the advice of a biostatician should be sought.
Nomogram mora biti linearen v zahtevanem območju koncentracij ogljika.
GUIDANCE FOR VERY FAST DEPURATING TEST SUBSTANCES
Primeri so prikazani v nadaljevanju.
As discussed in paragraph 129 of the test method, some substances may depurate so fast that a reliable time zero concentration, C0,d, and k2 cannot be derived because in samples very early in the depuration phase (i.e. from the second depuration sample onwards) the substance is effectively no longer measured (concentrations reported at the limit of quantification).
ti primeri se ne smejo uporabiti za pretvorbo; ključnega pomena je, da laboratoriji pripravijo svoje nomograme.
This situation was observed in the ring test carried out in support of this test method with benzo[a]pyrene, and has been documented in the validation report for the method.
Regresija mg/l suhe teže na mg C/1.
In such cases linear regression cannot be carried out reliably, and is likely to give an unrealistically high estimate of C0,d, resulting in an apparent assimilation efficiency much greater than 1.
Podatki iz koncentriranih suspenzij v polkontinuirani seriji gojenih celic, ponovno suspendiranih v destilirani vodi.
It is possible to calculate a conservative estimate of k2 and an “upper bound” BMF in these instances.
os x: mg C/1 koncentrirane hrane iz alg
Using those data points of the depuration phase where a concentration was measured, up to and including the first “non-detect” concentration (concentration set at limit of quantification), a linear regression (using natural logarithm transformed concentration data against time) will give an estimate of k2.
os y: mg/1 suhe teže koncentrirane hrane iz alg
For these sorts of cases this is likely only to involve two data points (e.g. sample days 1 and 2 of depuration) and then k2 can be estimated using Equation A5.22 in Appendix 5.
Korekcijski koeficient -0,980
This k2 estimate can be used to estimate an assimilation efficiency according to equation A7.1, substituting the C0,d value in the equation with the measured time zero concentration (C0,m) in cases where C0,d is clearly estimated to be much higher than could have been achievable in the test.
Regresija števila celic na mg C/1.
If C0,m was not measureable, then the limit of detection in fish tissue should be used.
os y: št. celic/1 koncentrirane hrane iz alg
If, in some cases, this gives a value of α > 1, then the assimilation efficiency is assumed to 1 as a “worst case”.
Korekcijski koeficient -0,926
The maximum BMFK can then be estimated using Equation A7.4, and should be quoted as a “much less than” (<<) value.
Regresija absorbance na mg C/1 (1 cm dolžine poti).
For example, for a study carried out with a feeding rate of 3 % and a depuration half-life less than 3 days, and a “worst case” α of 1, the BMFK is likely to be below about 0,13.
os y: absorbanca pri 440 nm pri 1/10 razredčitvi koncentrirane hrane iz alg
Given the purpose of this estimation and the fact that values will be conservative in nature, it is not necessary to correct them for growth dilution or fish and food lipid content.
Korekcijski koeficient -0,998
In some regions it may only be possible to obtain fish food with a lipid concentration that falls far short of this upper limit.
PRIMER PODATKOVNEGA LISTA ZA BELEŽENJE OBNAVLJANJA MEDIJEV, FIZIKALNIH/KEMIJSKIH PODATKOV O SPREMLJANJU, HRANJENJA, RAZMNOŽEVANJA VODNIH BOLH IN SMRTNOST STARŠEV
In such cases studies should be run with the lower lipid concentration in the food as supplied, and the feeding rate adjusted appropriately to maintain fish health.
Št. preskusa
Diet lipids should not be artificially increased by the addition of excess oil.
Datum začetka:
Appendix 8
Klon:
APPROACHES TO ESTIMATE TENTATIVE BCFS FROM DATA COLLECTED IN THE DIETARY EXPOSURE STUDY
Medij:
The dietary method is included in this test method for the bioaccumulation testing of substances that cannot in practice be tested using the aqueous exposure method.
Vrsta hrane:
The aqueous exposure method gives a bioconcentration factor, whereas the dietary method leads directly to information on feeding biomagnification potential.
Preskusna kemikalija:
In many chemical safety regimes information on aquatic bioconcentration is required (for example in risk assessment and the Globally Harmonization System of Classification).
Nominalna koncentracija:
Hence there is a need to use the data generated in a dietary study to estimate a bioconcentration factor that is comparable to tests conducted according to the aqueous exposure method [1].
Dan
This section explores approaches that may be followed to do this, while recognising the shortcomings that are inherent in the estimations.
Obnavljanje medija (označi)
The dietary study measures depuration to give a depuration rate constant, k2.
nova
If an uptake rate constant can be estimated with the available data for the situation where the fish had been exposed to the test substance via the water, then a kinetic BCF could be estimated.
Zagotovljena hrana (označi)
The estimation of an uptake rate constant for water exposure of a test substance is reliant on many assumptions, all of which will contribute to the estimate's uncertainty.
Št. živih potomcev [2]
Furthermore, this approach to estimating a BCF assumes that the overall rate of depuration (including contributory factors like distribution in the body and individual depuration processes) is independent of the exposure technique used to produce a test substance body burden.
Skupaj
The main assumptions inherent in the estimation approach can be summarised as follows.
Posoda 1
Depuration following dietary uptake is the same as depuration following aqueous exposure for a given substance
Skupna smrtnost staršev [3]
Uptake from water would follow first order kinetics
Navedite, katera posoda je bila uporabljena za preskus.
Depending on the method used to estimate uptake:
Zabeležite nedozorele zarode kot „AB“ v ustreznem okencu.
uptake can be correlated with fish weight alone
Zabeležite smrtnost katerega koli starša kot „M“ v ustreznem okencu.
uptake can be correlated with the substance's octanol-water partition coefficient alone
PRIMER PODATKOVNEGA LISTA ZA BELEŽENJE REZULTATOV KEMIJSKE ANALIZE
uptake can be correlated with a combination of fish weight and the substance's octanol-water partition coefficient
Izmerjene koncentracije
factors that can affect uptake in an aqueous exposure study in practice such as substance bioavailability, adsorption to apparatus, molecular size etc. have little effect
Nominalna koncentracija
and, crucially:
Vzorec v prvem tednu
The database (“training set”) used to develop the uptake estimation method is representative of the substance under consideration
Vzorec v drugem tednu
Several publications in the open literature have derived equations relating uptake from water in fish via the gills to a substance's octanol-water partition coefficient, fish weight (1) (2) (3) (4), volume and/or lipid content, membrane permeation/diffusion (5) (6), fish ventilation volume (7) and by a fugacity/mass balance approach (8) (9) (10).
Vzorec v tretjem tednu
A detailed appraisal of such methods in this context is given in Crookes & Brooke (11).
Svež
A publication by Barber (12) focussed on modelling bioaccumulation through dietary uptake is also useful in this context as it includes contributions from gill uptake rate models.
Star
A section of the background document to the 2004 dietary protocol (13) was also devoted to this aspect.
Izmerjene koncentracije kot odstotek nominalne vrednosti
Most of these models seem to have been derived using limited databases.
Tehtano povprečje v določenem časovnem intervalu Ker lahko koncentracija preskusne kemikalije v obdobju med obnavljanjem medija upade, je treba obravnavati, kakšno koncentracijo je treba izbrati kot reprezentativno za območje koncentracij, ki so jim izpostavljeni starši vrste Daphnia.
For models where details of the database used to build the model are available, it appears that the types of substances used are often of a similar structure or class (in terms of functionality, e.g. organochlorines).
Izbira mora temeljiti na bioloških in statističnih vidikih.
This adds to the uncertainty in using a model to predict an uptake rate constant for a different type of substance, in addition to test-specific considerations like species, temperature, etc.
Če naj bi na razmnoževanje na primer najbolj vplivala najvišja koncentracija, ki so ji živali izpostavljene, je treba uporabiti najvišjo koncentracijo.
A review of available techniques (11) highlighted that no one method is “more correct” than the others.
Če pa naj bi bil pomembnejši akumulirani ali dolgotrajni učinek toksične kemikalije, je ustrezneje izbrati povprečno koncentracijo.
Therefore, a clear justification should be given for the model used.
V tem primeru je ustrezno uporabiti tehtano povprečje v določenem časovnem intervalu za koncentracijo, saj ta upošteva spreminjanje trenutne koncentracije v odvisnosti od časa.
Where several methods are available for which the use can be justified, it may be prudent to present several estimates of k1 (and so BCF) or a range of k1 values (and BCF) according to several uptake estimation methods.
Primer tehtanega povprečja v določenem časovnem intervalu
However, given the differences in model types and datasets used to develop them, taking a mean value from estimates derived in different ways would not be appropriate.
Dnevi
Some researchers have postulated that BCF estimates of this sort require a bioavailability correction to account for a substance's adsorption to dissolved organic carbon (DOC) under aqueous exposure conditions, to bring the estimate in line with results from aqueous exposure studies (e.g. (13) (14)).
Slika 1 prikazuje primer (poenostavljenega) preskusa, ki je trajal sedem dni, medij pa se je obnavljal na dneve 0, 2 in 4.
Howeverl this correction may not be appropriate given the low levels of DOC required in an aqueous exposure study for a ‘worst case’ estimate (i.e. ratio of bioavailable substance to substance as measured in solution).
Tanka cikcakasta črta predstavlja koncentracijo v odvisnosti od časa.
For highly hydrophobic substances uptake at the gill may become limited by the rate of passive diffusion near the gill surface; in this case it is possible that the correction may be accounting for this effect rather than what it was designed for.
Predvideva se, da naj bi padec koncentracije sledil eksponentnemu procesu upadanja.
It is advised to focus on methods that require inputs for which data will be readily available for substances tested according to the dietary study described here (i.e. log KOW, fish weight).
Šest grafično prikazanih točk predstavlja opažene koncentracije, izmerjene na začetku in koncu vsakega obdobja obnavljanja.
Other methods that require more complex inputs may be applied, but may need additional measurements in the test or detailed knowledge on the test substance or fish species that may not be widely available.
Ravna debela črta prikazuje položaj tehtanega povprečja v določenem časovnem intervalu.
In addition, choice of model may be influenced by the level of validation and applicability domain (see (11) for a review and comparison of different methods).
Tehtano povprečje v določenem časovnem intervalu se izračuna tako, da je površina pod tehtanim povprečjem enaka površini pod krivuljo koncentracije.
It should be borne in mind that the resulting k1 estimate, and estimated BCF, are uncertain and may need to be treated in a weight-of-evidence approach along with the derived BMF and substance parameters (e.g. molecular size) for an overall picture of a substance's bioaccumulation potential.
Izračun za navedeni primer je prikazan v preglednici 1.
Interpretation and use of these parameters may depend on the regulatory framework.
Izračun tehtanega povprečja v določenem časovnem intervalu
Sijm D.T.H.M., Verberne M.E., de Jonge W.J., Pärt P. and Opperhuizen A. (1995), Allometry in the uptake of hydrophobic chemicals determined in vivo and in isolated perfused gills.
Obnavljanje št.
In the wild the route leading to greatest exposure in aqueous environments is likely to be through ingestion for very hydrophobic substances and so an estimated BCF is not strictly representative of such a substance's bioaccumulation potential.
Koncentracija 0
In Part C, Chapter C.20 is replaced by the following:
Koncentracija 1
Daphnia magna Reproduction Test
Ln (koncentracija 0)
This test method is equivalent to OECD test guideline (TG) 211 (2012).
Ln(koncentracija 1)
OECD test guidelines are periodically reviewed in the light of scientific progress.
Površina
The reproduction test guideline 211 originates from test guideline 202, Part II, Daphnia sp. reproduction test (1984).
Skupno dni:
It had generally been acknowledged that data from tests performed according to that TG 202 could be variable.
Skupna površina:
This led to considerable effort being devoted to the identification of the reasons for this variability with the aim of producing a better test method.
Tehtano povprečje:
Test guideline 211 is based on the outcome of these research activities, ring-tests and validation studies performed in 1992 (1), 1994 (2) and 2008 (3).
Dnevi je število dni v obdobju obnavljanja.
The main differences between the initial version (TG 202, 1984), and second version (TG 211, 1998) of the reproduction test guideline are:
Koncentracija 0 je koncentracija, izmerjena na začetku vsakega obdobja obnavljanja.
the recommended species to be used is Daphnia magna;
Koncentracija 1 je koncentracija, izmerjena na koncu vsakega obdobja obnavljanja.
the test duration is 21 days;
Ln(koncentracija 0) je naravni logaritem koncentracije 0.
for semi-static tests, the number of animals to be used at each test concentration has been reduced from at least 40, preferably divided into four groups of 10 animals, to at least 10 animals held individually (although different designs can be used for flow-through tests);
Ln(koncentracija 1) je naravni logaritem koncentracije 1.
more specific recommendations have been made with regard to test medium and feeding conditions.
Površina je površina pod eksponentno krivuljo za vsako obdobje obnavljanja.
the main differences between the second version of the reproduction test guideline (TG 211, 1998) and this version are:
Izračuna se z enačbo:
appendix 7 has been added to describe procedures for the identification of neonate sex if required.
Tehtano povprečje v določenem časovnem intervalu (tehtano povprečje) je skupna površina deljeno s skupno dni.
In line with previous versions of this test method sex ratio is an optional endpoint;
Seveda je treba za preskus razmnoževanja vrste Daphnia preglednico razširiti na 21 dni.
the response variable number of living offspring produced per surviving parental animal has been supplemented with an additional response variable for Daphnia reproduction, i.e. the total number of living offspring produced at the end of the test per parent daphnia at the start of the test excluding from the analysis parental accidental and/or inadvertent mortality.
Če se opazovanja opravijo samo na začetku in na koncu vsakega obdobja obnavljanje, seveda ni mogoče potrditi, ali je proces upadanja dejansko eksponenten.
The purpose of the added response variable is to align this response variable with other reproduction test methods on invertebrates.
Drugačna krivulja bi pomenila drugačen izračun za površino.
Furthermore, in relation to this response variable, it is possible, in this test method, to remove a source of error, namely the effect of inadvertent and/or accidental parental mortality, should that occur during the exposure period.
Vendar eksponentni proces upadanja ni nemogoč in je verjetno najboljša krivulja, ki se lahko uporabi, če ni na voljo drugih informacij.
additional statistical guidance for test design and for treatment of results has been included both for ECx (e.g. EC10 or EC50) and for NOEC/LOEC approach.
Previdno pa je treba obravnavati rezultate, če se s kemijsko analizo na koncu obdobja obnavljanja ne najde nobene kemikalije.
a limit test is introduced.
Če ni mogoče oceniti, kako hitro je kemikalija izginila iz raztopine, je nemogoče dobiti realistično površino pod krivuljo, zato je tudi nemogoče dobiti ustrezno tehtano povprečje v določenem časovnem intervalu.
Definitions used are given in Appendix 1.
SMERNICE ZA OPREDELJEVANJE SPOLA NOVOROJENIH ŽIVALI
The primary objective of the test is to assess the effect of chemicals on the reproductive output of Daphnia magna.
Do ustvarjanja novorojenih samcev lahko pride v spremenljivih okoljskih pogojih, kot so skrajšano obdobje osvetljenosti, temperatura, upadanje koncentracije v hrani in vedno večja gostota populacije (Hobaek in Larson, 1990; Kleiven idr., 1992).
To this end, young female Daphnia (the parent animals), aged less than 24 hours at the start of the test, are exposed to the test chemical added to water at a range of concentrations.
Ustvarjanje samcev je tudi znan odziv na določene regulatorje rasti žuželk (Oda idr., 2005).
The test duration is 21 days.
V pogojih, ko kemijski obremenilni dejavniki povzročajo upadanje števila za razmnoževanje sposobnih potomcev partenogenetskih samic, je mogoče pričakovati večje število samcev (OECD, 2008).
At the end of the test, the total number of living offspring produced is assessed.
Na podlagi razpoložljivih informacij ni mogoče predvideti, ali bo občutljivejše razmerje med spoloma ali končna točka razmnoževanja, obstajajo pa pokazatelji (glej „validacijsko poročilo“, del 1), da je to povečanje števila samcev morda manj občutljivo kot pa upadanje števila potomcev.
Reproductive output of the parent animals can be expressed in other ways (e.g. number of living offspring produced per animal per day from the first day offspring were observed) but these should be reported in addition to the total number of living offspring produced at the end of the test.
Ker je glavni namen te preskusne metode oceniti število ustvarjenih potomcev, je pojavljanje samcev neobvezno opažanje.
Because of the particular design of the semi-static test compared to other invertebrate reproduction test methods, it is also possible to count the number of living offspring produced by each individual parent animal.
Če se ta neobvezna končna točka oceni v študiji, je treba uporabiti dodatno merilo za veljavnost preskusa z ne več kot 5 % samci v kontrolah.
This enables that, contrary to other invertebrate reproduction test methods, if the parent animal dies accidentally and/or inadvertently during the test period, its offspring production can be excluded from data assessment.
Spol vrste Daphnia se najbolj praktično in preprosto ugotovi tako, da se uporabi njihove fenotipske značilnosti, saj so samci in samice genetsko identični, na določitev spola pa vpliva okolje.
Hence, if parental mortality occurs in exposed replicates, it should be considered whether or not the mortality follows a concentration-response pattern, e.g. if there is a significant regression of the response versus concentration of the test chemical with a positive slope (a statistical test like the Cochran-Armitage trend test may be used for this).
Samci in samice so si različni po dolžini in morfologiji sprednjih tipalk, ki so pri samcih daljše kot pri samicah (slika 1).
If the mortality does not follow a concentration-response pattern, then those replicates with parental mortality should be excluded from the analysis of the test result.
Razliko je mogoče prepoznati takoj po rojstvu, med odraščanjem pa se razvijejo tudi druge sekundarne spolne značilnosti (npr. glej sliko 2 v Olmstead in LeBlanc, 2000).
If the mortality follows a concentration-response pattern, the parental mortality should be assigned as an effect of the test chemical and the replicates should not be excluded from the analysis.
Za ugotavljanje morfološkega spola je treba novorojene živali, ustvarjene na vsako poskusno žival, prenesi s pipeto in jih vstaviti v petrijevko s preskusnim medijem.
If the parent animal dies during the test i.e. accidentally from mishandling or accident, or inadvertently due to unexplained incident not related to the effect of the test chemical or turns out to be male, then the replicate is excluded from the analysis (see more in paragraph 51).
Prostornina medija je čim manjša, da se omeji gibanje živali.