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Environmental fate & pathways

Biodegradation in water and sediment: simulation tests

Administrative data

Endpoint:
biodegradation in water and sediment: simulation tests
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1999
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: The study is a publication with detailed description of the method used.
Cross-referenceopen allclose all
Reason / purpose for cross-reference:
reference to same study
Reason / purpose for cross-reference:
reference to other study

Data source

Reference
Reference Type:
publication
Title:
The degradation of sodium O,O-dietyl dithiophosphate by bacteria from metalworking fluids
Author:
Sherburn, R. E & Large, P. J.
Year:
1999
Bibliographic source:
Letters in Applied Microbiology, 28, 61-65

Materials and methods

Test guideline
Qualifier:
no guideline followed
Deviations:
not applicable
Principles of method if other than guideline:
Bacteria were isolated from contaminated metalworking fluids and identified using standard biochemical tests. Bacteria were cultured with the test substance NaDDP (sodium O,O-diethyl phosphorodithioate) and analysed for the formation of degradation products.
GLP compliance:
not specified

Test material

Constituent 1
Reference substance name:
Sodium O,O-diethyl dithiophosphate
EC Number:
222-079-2
EC Name:
Sodium O,O-diethyl dithiophosphate
Cas Number:
3338-24-7
IUPAC Name:
sodium O,O-diethyl dithiophosphate
Details on test material:
- Name of test material (as cited in study report): Sodium O,O-diethyl dithiophosphate (O,O-diethyl phosphorodithioate; NaDDP)
Radiolabelling:
no

Study design

Oxygen conditions:
not specified
Inoculum or test system:
other: bacterial growth medium
Duration of test (contact time):
120 min
Initial test substance concentration
Initial conc.:
50 mmol/L
Based on:
test mat.
Parameter followed for biodegradation estimation:
other: Production of degradation products
Details on study design:
TEST CONDITIONS
- Composition of medium:
per 1 L of solution: 0.4 g MgSO4*7H2O, 7 g (NH4)SO4, 25 mg FeSO4*7H2O, 4.1 mg MnSO4*4H2O, 4.4 mg ZnSO4*7H2O, 0.79 mg CuSO4*5H2O, 73.4 mg CaCl2*2H2O, 80 mmol/L potassium sodium phosphate buffer (pH 7) and 50 mmol/L glycerol

TEST SYSTEM
ethanol was measured colorimemetrically with alcohol oxidase;
aldehydes were measured by the MBTH method;
phosphate was measured by the method of Lowry and Lopez;
hydrogen sulphide was measured by the method of Trüper and Schlegel;
acid phosphorodiesterase activity was measured by incubating extract in 2.2 mmol/L sodium citrate buffer (pH 6) with 0.1 mmol/L 2'-deoxythymidine-3'-(4-nitro-phenyl)phosphate for 5 min and stopping the reaction by adding 2.9 mL of 0.1 mol/L NaOH, absorbance was then measured at 405 nm;
alkaline phosphodiesterase activity was measured by incubating extract in 0.2 mol/L Tris-HCl (pH 8.9) containing 3.3 mg bis-4-nitrophenyl phosphate/mL, absorbance was determined at 405 nm;
protein concentrations were measured by the Bradford method with a bovine gamma-globulin standard.

SAMPLING
- Sampling frequency: every 5 minutes
Reference substance
Reference substance:
not specified

Results and discussion

Test performance:
Approximately 30 organisms were isolated from contaminated metalworking fluids. Most were gram-negative rod-shaped bacteria. Four organisms were selected for the study: AV1, CL1, FM2 and SP1.
Transformation products:
yes
Identity of transformation productsopen allclose all
Reference
Reference substance name:
Unnamed
IUPAC name:
alcohol
Identifier:
common name
Identity:
alcohol
Reference
Reference substance name:
Unnamed
IUPAC name:
aldehyde
Identifier:
common name
Identity:
aldehyde
Reference
Reference substance name:
Unnamed
IUPAC name:
phosphate
Inventory number:
InventoryMultipleMappingImpl [inventoryEntryValue=EC 604-302-9]
Identifier:
common name
Identity:
phosphate
Details on results:
Bacteria isolated from contaminated metalworking fluids:
AV1 (Flavobacterium) reduced nitrate, had urease activity, assimilated glucose, arabinose, mannose, N-acetyl-glucosamine, maltose and malate.
CL1 (Bacillus) reduced nitrate, had beta-glucosidase, beta-galactosidase activities and assimilated glucose, arabinose, mannose, mannitol, maltose, gluconate, malate and citrate.
FM2 (Aeromonas) produced indole and acid, had beta-glucosidase activity and assimilated N-acetylglucosamine, maltose and citrate.
SP1 (Pseudomonas) assimilated glucose, arabinose, mannose, N-acetylglucosamine, maltose and malate.

Formation of products from sodium diethyl dithiophosphate (NaDDP):
Extracts of all the organisms studied produced alcohol, aldehyde and phosphate in excess. No products were found in control experiments where boiled extracts were used or where the extract was omitted. In all cases, ethanol was present in lower detectable quantities than aldehyde or phosphate. Of the four organisms studied, Flavobacterium (AV1) appeared to catabolize the test material most rapidly. However, only 10% of the total phosphate of the NaDDP molecle was realized during the 2 hour study period. No hydrogen sulphide production by any of the four organisms was detected under the assay conditions used. Neither was alkaline phosphodiesterase activity detected.
Results with reference substance:
Not applicable

Any other information on results incl. tables

No other information.

Applicant's summary and conclusion

Validity criteria
Validity criteria fulfilled:
not applicable
Conclusions:
The breakdown of sodium O,O-diethyl dithiophosphate by four bacterial strains (Aeromonas, Pseudomonas, Flavobacterium and Bacillus) isolated from contaminated metalworking fluids was shown to involve the successive formation of ethanol, aldehyde and orthophosphate.
Executive summary:

Four bacterial strains were isolated from contaminated metalworking fluids and subsequently identified as Aeromonas, Pseudomonas, Flavobacterium and Bacillus.

These bacterial strains were cultured in the presence of the test substance sodium O,O-diethyl dithiophosphate and samples were taken every 5 minutes over a 2 hour period and examined for degradation products of the test substance.

Ethanol, aldehyde and orthophosphate were identified as breakdown products of the test substance.