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Bioaccumulation: aquatic/sediment

BCFBAF model (v3.01) of Estimation Programs Interface (EPI Suite, 2017) was used to predict the bioconcentration factor (BCF) of test chemical 6-Methoxy-2-naphthaldehyde (CAS No. 3453 -33 -6). The bioconcentration factor (BCF) of 6-Methoxy-2-naphthaldehyde was estimated to be 42.14 L/kg whole body w.w (at 25 deg C) which does not exceed the bioconcentration threshold of 2000, indicating that the chemical 6-Methoxy-2-naphthaldehyde is not expected to bioaccumulate in the food chain.

Additional information

Bioaccumulation: aquatic/sediment

Various predicted data for the target compound 6-Methoxy-2-naphthaldehyde(CAS No. 3453-33-6) and supporting weight of evidence study for its read across substance were reviewed for the bioaccumulation end point which are summarized as below:

 

In aprediction done using theBCFBAF Program(v3.01) of Estimation Programs Interface (EPI Suite, 2017) was used to predict the bioconcentration factor (BCF) of test chemical 6-Methoxy-2-naphthaldehyde (CAS No. 3453 -33 -6). The bioconcentration factor (BCF) of 6-Methoxy-2-naphthaldehyde was estimated to be 42.14 L/kg whole body w.w (at 25 deg C).

 

In an another prediction done by using Bio-concentration Factor (v12.1.0.50374) moduleACD (Advanced Chemistry Development)/I-Lab predictive module, 2017), theBCF over the entire pH scale (pH 1 -14) of the test substance 6-Methoxy-2-naphthaldehyde (CAS no. 3453 -33 -6) was estimated to be 77.2.

 

Bioconcentration Factor (BCF) of test chemical 6-Methoxy-2-naphthaldehyde (CAS no. 3453 -33 -6) was estimated using Chemspider database(ChemSpider, 2017). The bioconcentration factor of test substance 6-Methoxy-2-naphthaldehyde was estimated to be 93.69 at both pH 5.5 and 7.4, respectively.

 

Another predicted data was estimated usingSciFinder database (American Chemical Society (ACS), 2017) was used for predicting the bioconcentration factor (BCF) of test chemical 6-Methoxy-2-naphthaldehyde (CAS No. 3453 -33 -6). The bioconcentration factor (BCF) of 6-Methoxy-2-naphthaldehyde was estimated to be 58.7 (at 25 deg C).

 

From CompTox Chemistry Dashboard using OPERA (OPEn (quantitative) structure-activity Relationship Application) V1.02 model in which calculation based on PaDEL descriptors (calculate molecular descriptors and fingerprints of chemical), the bioaccumulation i.e BCF for test substance 6-Methoxy-2-naphthaldehyde was estimated to be 19.9 dimensionless. The predicted BCF result based on the 5 OECD principles. Thus based on the result it is concluded that the test substance 6-Methoxy-2-naphthaldehyde is non-bioaccumulative in nature.

 

In a supporting weight of evidence study from authoritative database (HSDB, 2017) for the read across chemical 1-butoxypropan-2-ol (CAS no. 121-33-5), bioaccumulation experiment in fish was conducted for estimating the BCF (bioaccumulation factor) value of read across chemical 1-butoxypropan-2-ol. The bioaccumulation factor (BCF) value was calculated using a log Kow of 1.37 and a regression equation. The estimated BCF (bioaccumulation factor) value of 1-butoxypropan-2-ol in fish was determined to be 3 dimensionless.

 

For theread across substance1-methoxynaphthalene (CAS no. 2216-09-5) from authoritative database (J-CHECK, 2017), bioaccumulation experiment was conducted on test organism Cyprinus carpio for 8 weeks for evaluating the bioconcentration factor (BCF value) of substance 1-methoxynaphthalene. The study was performed according to other guideline "Bioaccumulation test of a chemical substance in fish or shellfish" provided in "the Notice on the Test Method Concerning New Chemical Substances", respectively. Cyprinus carpio was used as a test organism for the study. Details on analytical methods involve the recovery ratio: Test water: 1st concentration area : 88.9%, 2nd concentration area : 92.1%, Fish : 81.6%, - Limit of detection: Fish: 0.003 ppm. Tween 80 was used as a vehicle. Test chemical nominal conc. used for the study were 0.02 mg/l and 0.002 mg/l, respectively. Range finding study involve the TLm(48 hr) 9.5 mg/l (w/v) on Rice fish (Oryzias latipes). Lipid content of the test organism was determined to be 5.4%.The bioconcentration factor (BCF value) of substance 1-methoxynaphthalene on Cyprinus carpio was determined to be 130 and 259 L/Kg at a conc. of 0.02 mg/l and 106 and 221 L/Kg at a conc. of 0.002 mg/l, respectively.

 

On the basis of above results for target chemical6-Methoxy-2-naphthaldehyde(from EPI suite, ACD labs,ChemSpider, SciFinder database and CompTox Chemistry Dashboard,  2017) and for its read across substance (from authoritative database J-CHECK and HSDB, 2017), it can be concluded that the BCF value of test substance6-Methoxy-2-naphthaldehyderanges from 19.9 – 93.69 which does not exceed the bioconcentration threshold of 2000, indicating that the chemical6-Methoxy-2-naphthaldehydeis not expected to bioaccumulate in the food chain.